# This file contains tests that specifically exercise the internal representation
# of a list.
#
# Copyright © 2022 Ashok P. Nadkarni
#
# See the file "license.terms" for information on usage and redistribution
# of this file, and for a DISCLAIMER OF ALL WARRANTIES.

# Unlike the other files related to list commands which for the most part do
# black box testing focusing on functionality, this file does more of white box
# testing to exercise code paths that implement different list representations
# (with spans, leading free space etc., shared/unshared etc.) In addition to
# functional correctness, the tests also check for the expected internal
# representation as that pertains to performance heuristics. Generally speaking,
# combinations of the following need to be tested,
# - free space in front, back, neither, both of list representation
# - shared Tcl_Objs
# - shared internal reps (independent of shared Tcl_Objs)
# - byte-compiled vs non-compiled
#
# Being white box tests, they are sensitive to changes to further optimizations
# and changes in heuristics. That cannot be helped.

if {"::tcltest" ni [namespace children]} {
    package require tcltest 2.5
    namespace import -force ::tcltest::*
}

::tcltest::loadTestedCommands
catch [list package require -exact tcl::test [info patchlevel]]

testConstraint testlistrep [llength [info commands testlistrep]]

proc describe {l args} {dict get [testlistrep describe $l] {*}$args}

proc irange {first last} {
    set l {}
    while {$first <= $last} {
	lappend l $first
	incr first
    }
    return $l
}
proc leadSpace {l} {
    # Returns the leading space in a list store
    return [dict get [describe $l] store firstUsed]
}
proc tailSpace {l} {
    # Returns the trailing space in a list store
    array set rep [describe $l]
    dict with rep(store) {
	return [expr {$numAllocated - ($firstUsed + $numUsed)}]
    }
}
proc allocated {l} {
    # Returns the allocated space in a list store
    return [dict get [describe $l] store numAllocated]
}
proc repStoreRefCount {l} {
    # Returns the ref count for the list store
    return [dict get [describe $l] store refCount]
}
proc validate {l} {
    # Panics if internal listrep structures are not valid
    testlistrep validate $l
}
proc leadSpaceMore {l} {
    set leadSpace [leadSpace $l]
    expr {$leadSpace > 0 && $leadSpace >= 2*[tailSpace $l]}
}
proc tailSpaceMore {l} {
    set tailSpace [tailSpace $l]
    expr {$tailSpace > 0 && $tailSpace >= 2*[leadSpace $l]}
}
proc spaceEqual {l} {
    # 1 if lead and tail space shared (diff of 1 at most) and more than 0
    set leadSpace [leadSpace $l]
    set tailSpace [tailSpace $l]
    if {$leadSpace == 0 && $tailSpace == 0} {
	# At least one must be positive
	return 0
    }
    set diff [expr {$leadSpace - $tailSpace}]
    return [expr {$diff >= -1 && $diff <= 1}]
}
proc storeAddress {l} {
    return [describe $l store memoryAddress]
}
proc sameStore {l1 l2} {
    expr {[storeAddress $l1] == [storeAddress $l2]}
}
proc hasSpan {l args} {
    # Returns 1 if list has a span. If args are specified, they are checked with
    # span values (start and length)
    array set rep [describe $l]
    if {![info exists rep(span)]} {
	return 0
    }
    if {[llength $args] == 0} {
	return 1; # No need to check values
    }
    lassign $args start len
    if {[dict get $rep(span) spanStart] == $start &&
	[dict get $rep(span) spanLength] == $len} {
	return 1
    }
    return 0
}
proc checkListrep {l listLen numAllocated leadSpace tailSpace {refCount 0}} {
    # Checks if the internal representation of $l match
    # passed arguments. Return "" if yes, else error messages.
    array set rep [testlistrep describe $l]

    set rep(leadSpace) [dict get $rep(store) firstUsed]
    set rep(numAllocated) [dict get $rep(store) numAllocated]
    set rep(tailSpace) [expr {
			      $rep(numAllocated) - ($rep(leadSpace) + [dict get $rep(store) numUsed])
			  }]
    set rep(refCount) [dict get $rep(store) refCount]

    if {[info exists rep(span)]} {
	set rep(listLen) [dict get $rep(span) spanLength]
    } else {
	set rep(listLen) [dict get $rep(store) numUsed]
    }

    set errors [list]
    foreach arg {listLen numAllocated leadSpace tailSpace} {
	if {$rep($arg) != [set $arg]} {
	    lappend errors "$arg in list representation ($rep($arg)) is not expected value ([set $arg])."
	}
    }
    # Check refCount only if caller has specified it as non-0
    if {$refCount && $refCount != $rep(refCount)} {
	lappend errors "refCount in list representation ($rep(refCount)) is not expected value ($refCount)."
    }
    return $errors
}

proc assertListrep {l listLen numAllocated leadSpace tailSpace {refCount 0}} {
    # Like check_listrep but raises error
    set errors [checkListrep $l $listLen $numAllocated $leadSpace $tailSpace $refCount]
    if {[llength $errors]} {
	error [join $errors \n]
    }
    return
}

# The default length should be large enough that doubling the allocation will
# clearly distinguish free space allocation difference between front and back.
# (difference in the two should at least be 2 else we cannot tell if front
# or back was favored appropriately)
proc freeSpaceNone {{len 8}} {return [testlistrep new $len 0 0]}
proc freeSpaceLead {{len 8} {lead 3}} {return [testlistrep new $len $lead 0]}
proc freeSpaceTail {{len 8} {tail 3}} {return [testlistrep new $len 0 $tail]}
proc freeSpaceBoth {{len 8} {lead 3} {tail 3}} {
    return [testlistrep new $len $lead $tail]
}
proc zombieSample {{len 1000} {leadzombies 100} {tailzombies 100}} {
    # returns an unshared listrep with zombies in front and back

    # don't combine freespacenone and lrange else zombies are freed
    set l [freeSpaceNone [expr {$len+$leadzombies+$tailzombies}]]
    return [lrange $l $leadzombies [expr {$leadzombies+$len-1}]]
}

# Just ensure above stubs return what's expected
if {[testConstraint testlistrep]} {
    assertListrep [freeSpaceNone] 8 8 0 0 1
    assertListrep [freeSpaceLead] 8 11 3 0 1
    assertListrep [freeSpaceTail] 8 11 0 3 1
    assertListrep [freeSpaceBoth] 8 14 3 3 1
    assertListrep [zombieSample] 1000 1200 0 0 1
    if {![hasSpan [zombieSample]] || [dict get [testlistrep describe [zombieSample]] span spanStart] == 0} {
	error "zombieSample span missing or span start is at 0."
    }
}

# Define some variables for some indices because the Tcl compiler will do some
# operations completely in byte code if indices are literals
set zero 0
set one 1
set two 2
set four 4
set end end

#
# Test sets:
# 1.* - unshared internal rep, no spans, with no free space
# 2.* - shared internal rep, no spans, with no free space
# 3.* - unshared internal rep, spanned
# 4.* - shared internal rep, spanned
# 5.* - shared Tcl_Obj
# 6.* - lists with zombie Tcl_Obj's

#
# listrep-1.* tests all operate on unshared listreps with no free space

test listrep-1.1 {
    Inserts in front of unshared list with no free space should reallocate with
    equal free space at front and back -- linsert version
} -constraints testlistrep -body {
    set l [linsert [freeSpaceNone] $zero 99]
    validate $l
    list $l [spaceEqual $l]
} -result [list {99 0 1 2 3 4 5 6 7} 1]

test listrep-1.1.1 {
    Inserts in front of unshared list with no free space should reallocate with
    equal free space at front and back -- lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone] $zero -1 99]
    validate $l
    list $l [spaceEqual $l]
} -result [list {99 0 1 2 3 4 5 6 7} 1]

test listrep-1.2 {
    Inserts at back of unshared list with no free space should allocate all
    space at back -- linsert version
} -constraints testlistrep -body {
    set l [linsert [freeSpaceNone] $end 99]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 2 3 4 5 6 7 99} 0 4]

test listrep-1.2.1 {
    Inserts at back of unshared list with no free space should allocate all
    space at back -- lset version
} -constraints testlistrep -body {
    set l [freeSpaceNone]
    lset l $end+1 99
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 2 3 4 5 6 7 99} 0 4]

test listrep-1.2.2 {
    Inserts at back of unshared list with no free space should allocate all
    space at back -- lappend version
} -constraints testlistrep -body {
    set l [freeSpaceNone]
    lappend l 99
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 2 3 4 5 6 7 99} 0 4]

test listrep-1.3 {
    Inserts in middle of unshared list with no free space should reallocate with
    equal free space at front and back - linsert version
} -constraints testlistrep -body {
    set l [linsert [freeSpaceNone] $four 99]
    validate $l
    list $l [spaceEqual $l]
} -result [list {0 1 2 3 99 4 5 6 7} 1]

test listrep-1.3.1 {
    Inserts in middle of unshared list with no free space should reallocate with
    equal free space at front and back - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone] $four $four-1 99]
    validate $l
    list $l [spaceEqual $l]
} -result [list {0 1 2 3 99 4 5 6 7} 1]

test listrep-1.4 {
    Deletes from front of small unshared list with no free space should
    just shift up leaving room at back - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone] $zero $zero]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {1 2 3 4 5 6 7} 0 1]

test listrep-1.4.1 {
    Deletes from front of small unshared list with no free space should
    just shift up leaving room at back - lassign version
} -constraints testlistrep -body {
    set l [lassign [freeSpaceNone] e]
    validate $l
    list $e $l [leadSpace $l] [tailSpace $l]
} -result [list 0 {1 2 3 4 5 6 7} 0 1]

test listrep-1.4.2 {
    Deletes from front of small unshared list with no free space should
    just shift up leaving room at back - lpop version
} -constraints testlistrep -body {
    set l [freeSpaceNone]
    set e [lpop l $zero]
    validate $l
    list $e $l [leadSpace $l] [tailSpace $l]
} -result [list 0 {1 2 3 4 5 6 7} 0 1]

test listrep-1.4.3 {
    Deletes from front of small unshared list with no free space should
    just shift up leaving room at back - lrange version
} -constraints testlistrep -body {
    set l [lrange [freeSpaceNone] $one $end]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {1 2 3 4 5 6 7} 0 1]

test listrep-1.4.4 {
    Deletes from front of small unshared list with no free space should
    just shift up leaving room at back - lremove version
} -constraints testlistrep -body {
    set l [lremove [freeSpaceNone] $zero]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {1 2 3 4 5 6 7} 0 1]

test listrep-1.5 {
    Deletes from front of large unshared list with no free space should
    create a span - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone 1000] $zero $one]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 2 998]
} -result [list [irange 2 999] 2 0 1]

test listrep-1.5.1 {
    Deletes from front of large unshared list with no free space should
    create a span - lassign version
} -constraints testlistrep -body {
    set l [lassign [freeSpaceNone 1000] e]
    validate $l
    list $e $l [leadSpace $l] [tailSpace $l] [hasSpan $l 1 999]
} -result [list 0 [irange 1 999] 1 0 1]

test listrep-1.5.2 {
    Deletes from front of large unshared list with no free space should
    create a span - lrange version
} -constraints testlistrep -body {
    set l [lrange [freeSpaceNone 1000] $two end]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 2 998]
} -result [list [irange 2 999] 2 0 1]

test listrep-1.5.3 {
    Deletes from front of large unshared list with no free space should
    create a span - lremove version
} -constraints testlistrep -body {
    set l [lremove [freeSpaceNone 1000] $zero]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 1 999]
} -result [list [irange 1 999] 1 0 1]

test listrep-1.5.4 {
    Deletes from front of large unshared list with no free space should
    create a span - lpop version
} -constraints testlistrep -body {
    set l [freeSpaceNone 1000]
    set e [lpop l 0]
    validate $l
    list $e $l [leadSpace $l] [tailSpace $l] [hasSpan $l 1 999]
} -result [list 0 [irange 1 999] 1 0 1]

test listrep-1.6 {
    Deletes closer to front of large list should move (smaller) front segment
    -- lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone 1000] $four $four]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 1 999]
} -result [list [concat [irange 0 3] [irange 5 999]] 1 0 1]

test listrep-1.6.1 {
    Deletes closer to front of large list should move (smaller) front segment
    -- lpop version
} -constraints testlistrep -body {
    set l [freeSpaceNone 1000]
    set e [lpop l $four]
    validate $l
    list $e $l [leadSpace $l] [tailSpace $l] [hasSpan $l 1 999]
} -result [list 4 [concat [irange 0 3] [irange 5 999]] 1 0 1]

test listrep-1.7 {
    Deletes closer to back of large list should move (smaller) back segment
    and will not need a span - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone 1000] end-$four end-$four]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list [concat [irange 0 994] [irange 996 999]] 0 1 0]

test listrep-1.7.1 {
    Deletes closer to back of large list should move (smaller) back segment
    and will not need a span - lpop version
} -constraints testlistrep -body {
    set l [freeSpaceNone 1000]
    set e [lpop l $end-4]
    validate $l
    list $e $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list 995 [concat [irange 0 994] [irange 996 999]] 0 1 0]

test listrep-1.8 {
    Deletes at back of small unshared list should not need a span - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone] end-$one end]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list {0 1 2 3 4 5} 0 2 0]

test listrep-1.8.1 {
    Deletes at back of small unshared list should not need a span - lrange version
} -constraints testlistrep -body {
    set l [lrange [freeSpaceNone] $zero end-$two]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list {0 1 2 3 4 5} 0 2 0]

test listrep-1.8.2 {
    Deletes at back of small unshared list should not need a span - lremove version
} -constraints testlistrep -body {
    set l [lremove [freeSpaceNone] $end-1 $end]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list {0 1 2 3 4 5} 0 2 0]

test listrep-1.8.3 {
    Deletes at back of small unshared list should not need a span - lpop version
} -constraints testlistrep -body {
    set l [freeSpaceNone]
    set e [lpop l $end]
    validate $l
    list $e $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list 7 {0 1 2 3 4 5 6} 0 1 0]

test listrep-1.9 {
    Deletes at back of large unshared list should not need a span - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone 1000] end-$four end]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list [irange 0 994] 0 5 0]

test listrep-1.9.1 {
    Deletes at back of large unshared list should not need a span - lrange version
} -constraints testlistrep -body {
    set l [lrange [freeSpaceNone 1000] 0 $end-5]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list [irange 0 994] 0 5 0]

test listrep-1.9.2 {
    Deletes at back of large unshared list should not need a span - lremove version
} -constraints testlistrep -body {
    set l [lremove [freeSpaceNone 1000] end-$four $end-3 end-$two $end-1 $end]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list [irange 0 994] 0 5 0]

test listrep-1.9.3 {
    Deletes at back of large unshared list should not need a span - lpop version
} -constraints testlistrep -body {
    set l [freeSpaceNone 1000]
    set e [lpop l $end]
    validate $l
    list $e $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list 999 [irange 0 998] 0 1 0]

test listrep-1.10 {
    no-op on unshared list should force a canonical list string - lreplace version
} -body {
    lreplace {    1 2   3 4   } $zero -1
} -result {1 2 3 4}

test listrep-1.10.1 {
    no-op on unshared list should force a canonical list string - lrange version
} -body {
    lrange {    1 2   3 4   } $zero $end
} -result {1 2 3 4}

test listrep-1.11 {
    Append elements to large unshared list is optimized as lappend
    so no free space in front - lreplace version
} -constraints testlistrep -body {
    # Note $end, not end else byte code compiler short-cuts
    set l [lreplace [freeSpaceNone 1000] $end+1 $end+1 1000]
    validate $l
    list $l [leadSpace $l] [expr {[tailSpace $l] > 0}] [hasSpan $l]
} -result [list [irange 0 1000] 0 1 0]

test listrep-1.11.1 {
    Append elements to large unshared list is optimized as lappend
    so no free space in front - linsert version
} -constraints testlistrep -body {
    # Note $end, not end else byte code compiler short-cuts
    set l [linsert [freeSpaceNone 1000] $end+1 1000]
    validate $l
    list $l [leadSpace $l] [expr {[tailSpace $l] > 0}] [hasSpan $l]
} -result [list [irange 0 1000] 0 1 0]

test listrep-1.11.2 {
    Append elements to large unshared list leaves no free space in front
    - lappend version
} -constraints testlistrep -body {
    # Note $end, not end else byte code compiler short-cuts
    set l [freeSpaceNone 1000]
    lappend l 1000 1001
    validate $l
    list $l [leadSpace $l] [expr {[tailSpace $l] > 0}] [hasSpan $l]
} -result [list [irange 0 1001] 0 1 0]


test listrep-1.12 {
    Replacement of elements at front with same number elements in unshared list
    is in-place - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone] $zero $one 10 11]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {10 11 2 3 4 5 6 7} 0 0]

test listrep-1.12.1 {
    Replacement of elements at front with same number elements in unshared list
    is in-place - lset version
} -constraints testlistrep -body {
    set l [freeSpaceNone]
    lset l 0 -1
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {-1 1 2 3 4 5 6 7} 0 0]

test listrep-1.13 {
    Replacement of elements at front with fewer elements in unshared list
    results in a spanned list with space only in front
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone] $zero $four 10]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {10 5 6 7} 4 0]

test listrep-1.14 {
    Replacement of elements at front with more elements in unshared list
    results in a reallocated spanned list with space at front and back
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone] $zero $one 10 11 12]
    validate $l
    list $l [spaceEqual $l]
} -result [list {10 11 12 2 3 4 5 6 7} 1]

test listrep-1.15 {
    Replacement of elements in middle with same number elements in unshared list
    is in-place - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone] $one $two 10 11]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 10 11 3 4 5 6 7} 0 0]

test listrep-1.15.1 {
    Replacement of elements in middle with same number elements in unshared list
    is in-place - lset version
} -constraints testlistrep -body {
    set l [freeSpaceNone]
    lset l $two -1
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 -1 3 4 5 6 7} 0 0]

test listrep-1.16 {
    Replacement of elements in front half with fewer elements in unshared list
    results in a spanned list with space only in front since smaller segment moved
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone] $one $four 10]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 10 5 6 7} 3 0]

test listrep-1.17 {
    Replacement of elements in back half with fewer elements in unshared list
    results in a spanned list with space only at back
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone] end-$four end-$one 10]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 2 10 7} 0 3]

test listrep-1.18 {
    Replacement of elements in middle more elements in unshared list
    results in a reallocated spanned list with space at front and back
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone] $one $two 10 11 12]
    validate $l
    list $l [spaceEqual $l]
} -result [list {0 10 11 12 3 4 5 6 7} 1]

test listrep-1.19 {
    Replacement of elements at back with same number elements in unshared list
    is in-place - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone] $end-1 $end 10 11]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 2 3 4 5 10 11} 0 0]

test listrep-1.19.1 {
    Replacement of elements at back with same number elements in unshared list
    is in-place - lset version
} -constraints testlistrep -body {
    set l [freeSpaceNone]
    lset l $end 10
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 2 3 4 5 6 10} 0 0]

test listrep-1.20 {
    Replacement of elements at back with fewer elements in unshared list
    is in-place with space only at the back
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone] $end-2 $end 10]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 2 3 4 10} 0 2]

test listrep-1.21 {
    Replacement of elements at back with more elements in unshared list
    allocates new representation with equal space at front and back
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceNone] $end-1 $end 10 11 12]
    validate $l
    list $l [spaceEqual $l]
} -result [list {0 1 2 3 4 5 10 11 12} 1]

#
# listrep-2.* tests all operate on shared list reps with no free space. Note the
# *list internal rep* must be shared, not only the Tcl_Obj so just assigning to
# another variable does not suffice. The lrange construct on an variable's value
# will do the needful.

test listrep-2.1 {
    Inserts in front of shared list with no free space should reallocate with
    more leading space in front - linsert version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [linsert $b $zero 99]
    validate $l
    list [repStoreRefCount $b] $l [leadSpaceMore $l] [repStoreRefCount $l]
} -result [list 2 {99 0 1 2 3 4 5 6 7} 1 1]

test listrep-2.1.1 {
    Inserts in front of shared list with no free space should reallocate with
    more leading space in front - lreplace version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lreplace $b $zero -1 99]
    validate $l
    list [repStoreRefCount $b] $l [leadSpaceMore $l] [repStoreRefCount $l]
} -result [list 2 {99 0 1 2 3 4 5 6 7} 1 1]

test listrep-2.2 {
    Inserts at back of shared list with no free space should reallocate with
    more leading space in back - linsert version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [linsert $b $end 99]
    validate $l
    list [repStoreRefCount $b] $l [tailSpaceMore $l] [repStoreRefCount $l]
} -result [list 2 {0 1 2 3 4 5 6 7 99} 1 1]

test listrep-2.2.1 {
    Inserts at back of shared list with no free space should reallocate with
    more leading space in back - lreplace version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lreplace $b $end+1 end+$one 99]
    validate $l
    list [repStoreRefCount $b] $l [tailSpaceMore $l] [repStoreRefCount $l]
} -result [list 2 {0 1 2 3 4 5 6 7 99} 1 1]

test listrep-2.2.2 {
    Inserts at back of shared list with no free space should reallocate with
    more leading space in back - lappend version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lappend b 99]
    validate $l
    list [repStoreRefCount $b] $l [tailSpaceMore $l] [repStoreRefCount $l]
} -result [list 1 {0 1 2 3 4 5 6 7 99} 1 1]

test listrep-2.2.3 {
    Inserts at back of shared list with no free space should reallocate with
    more leading space in back - lset version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lset b $end+1 99]
    validate $l
    list [repStoreRefCount $b] $l [tailSpaceMore $l] [repStoreRefCount $l]
} -result [list 1 {0 1 2 3 4 5 6 7 99} 1 1]

test listrep-2.3 {
    Inserts in middle of shared list with no free space should reallocate with
    equal spacing - linsert version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [linsert $b $four 99]
    validate $l
    list [repStoreRefCount $b] $l [spaceEqual $l] [repStoreRefCount $l]
} -result [list 2 {0 1 2 3 99 4 5 6 7} 1 1]

test listrep-2.3.1 {
    Inserts in middle of shared list with no free space should reallocate with
    equal spacing - lreplace version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lreplace $b $four $four-1 99]
    validate $l
    list [repStoreRefCount $b] $l [spaceEqual $l] [repStoreRefCount $l]
} -result [list 2 {0 1 2 3 99 4 5 6 7} 1 1]

test listrep-2.4 {
    Deletes from front of small shared list with no free space should
    allocate new list of exact size - lreplace version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lreplace $b $zero $zero]
    validate $l
    list [repStoreRefCount $b] $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 2 {1 2 3 4 5 6 7} 0 0 1]

test listrep-2.4.1 {
    Deletes from front of small shared list with no free space should
    allocate new list of exact size - lremove version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lremove $b $zero $one]
    validate $l
    list [repStoreRefCount $b] $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 2 {2 3 4 5 6 7} 0 0 1]

test listrep-2.4.2 {
    Deletes from front of small shared list with no free space should
    allocate new list of exact size - lrange version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lrange $b $one $end]
    validate $l
    list [repStoreRefCount $b] $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 2 {1 2 3 4 5 6 7} 0 0 1]

test listrep-2.4.3 {
    Deletes from front of small shared list with no free space should
    allocate new list of exact size - lassign version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lassign $b e]
    validate $l
    list $e [repStoreRefCount $b] $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 0 2 {1 2 3 4 5 6 7} 0 0 1]

test listrep-2.4.4 {
    Deletes from front of small shared list with no free space should
    allocate new list of exact size - lpop version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set l [lrange $a $zero end]; # Ensure shared listrep
    set e [lpop l $zero]
    validate $l
    list $e $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 0 {1 2 3 4 5 6 7} 0 0 1]

test listrep-2.5 {
    Deletes from front of large shared list with no free space should
    create span - lreplace version
} -constraints testlistrep -body {
    set a [freeSpaceNone 1000]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lreplace $b $zero $zero]
    validate $l
    # The listrep store should be shared among a, b, l (3 refs)
    list [sameStore $b $l] [repStoreRefCount $b] $l [hasSpan $l] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 1 3 [irange 1 999] 1 0 0 3]

test listrep-2.5.1 {
    Deletes from front of large shared list with no free space should
    create span - lremove version
} -constraints testlistrep -body {
    set a [freeSpaceNone 1000]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lremove $b $zero $one]
    validate $l
    # The listrep store should be shared among a, b, l (3 refs)
    list [sameStore $b $l] [repStoreRefCount $b] $l [hasSpan $l] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 1 3 [irange 2 999] 1 0 0 3]

test listrep-2.5.2 {
    Deletes from front of large shared list with no free space should
    create span - lrange version
} -constraints testlistrep -body {
    set a [freeSpaceNone 1000]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lrange $b $two $end]
    validate $l
    # The listrep store should be shared among a, b, l (3 refs)
    list [sameStore $b $l] [repStoreRefCount $b] $l [hasSpan $l] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 1 3 [irange 2 999] 1 0 0 3]

test listrep-2.5.3 {
    Deletes from front of large shared list with no free space should
    create span - lassign version
} -constraints testlistrep -body {
    set a [freeSpaceNone 1000]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lassign $b e]
    validate $l
    # The listrep store should be shared among a, b, l (3 refs)
    list $e [sameStore $b $l] [repStoreRefCount $b] $l [hasSpan $l] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 0 1 3 [irange 1 999] 1 0 0 3]

test listrep-2.5.4 {
    Deletes from front of large shared list with no free space should
    create span - lpop version
} -constraints testlistrep -body {
    set a [freeSpaceNone 1000]
    set l [lrange $a $zero end]; # Ensure shared listrep
    set e [lpop l $zero]
    validate $l
    # The listrep store should be shared among a, b, l (3 refs)
    list $e $l [hasSpan $l] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 0 [irange 1 999] 1 0 0 2]

test listrep-2.6 {
    Deletes from back of small shared list with no free space should
    allocate new list of exact size - lreplace version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lreplace $b $end $end]
    validate $l
    list [repStoreRefCount $b] $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 2 {0 1 2 3 4 5 6} 0 0 1]

test listrep-2.6.1 {
    Deletes from back of small shared list with no free space should
    allocate new list of exact size - lremove version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lremove $b $end $end-1]
    validate $l
    list [repStoreRefCount $b] $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 2 {0 1 2 3 4 5} 0 0 1]

test listrep-2.6.2 {
    Deletes from back of small shared list with no free space should
    allocate new list of exact size - lrange version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lrange $b $zero $end-1]
    validate $l
    list [repStoreRefCount $b] $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 2 {0 1 2 3 4 5 6} 0 0 1]

test listrep-2.6.3 {
    Deletes from back of small shared list with no free space should
    allocate new list of exact size - lpop version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set l [lrange $a $zero end]; # Ensure shared listrep
    set e [lpop l]
    validate $l
    list $e $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 7 {0 1 2 3 4 5 6} 0 0 1]

test listrep-2.7 {
    Deletes from back of large shared list with no free space should
    use a span - lreplace version
} -constraints testlistrep -body {
    set a [freeSpaceNone 1000]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lreplace $b $end $end]
    validate $l
    # Note lead and tail space is 0 because original list store in a,b is used
    list [repStoreRefCount $b] $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 3 [irange 0 998] 0 0 3]

test listrep-2.7.1 {
    Deletes from back of large shared list with no free space should
    use a span - lremove version
} -constraints testlistrep -body {
    set a [freeSpaceNone 1000]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lremove $b $end-1 $end]
    validate $l
    # Note lead and tail space is 0 because original list store in a,b is used
    list [repStoreRefCount $b] $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 3 [irange 0 997] 0 0 3]

test listrep-2.7.2 {
    Deletes from back of large shared list with no free space should
    use a span - lrange version
} -constraints testlistrep -body {
    set a [freeSpaceNone 1000]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lrange $b $zero $end-1]
    validate $l
    # Note lead and tail space is 0 because original list store in a,b is used
    list [repStoreRefCount $b] $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 3 [irange 0 998] 0 0 3]

test listrep-2.7.3 {
    Deletes from back of large shared list with no free space should
    use a span - lpop version
} -constraints testlistrep -body {
    set a [freeSpaceNone 1000]
    set l [lrange $a $zero end]; # Ensure shared listrep
    set e [lpop l]
    validate $l
    # Note lead and tail space is 0 because original list store in a,b is used
    list $e $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 999 [irange 0 998] 0 0 2]

test listrep-2.8 {
    no-op on shared list should force a canonical list representation
    with original unchanged - lreplace version
} -body {
    set l {     1 2   3 4   }
    list [lreplace $l $zero -1] $l
} -result [list {1 2 3 4} {     1 2   3 4   }]

test listrep-2.8.1 {
    no-op on shared list should force a canonical list representation
    with original unchanged - lrange version
} -body {
    set l {     1 2   3 4   }
    list [lrange $l $zero end] $l
} -result [list {1 2 3 4} {     1 2   3 4   }]

test listrep-2.9 {
    Appends to back of large shared list with no free space allocates new
    list with space only at the back - lreplace version
} -constraints testlistrep -body {
    set a [freeSpaceNone 1000]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lreplace $b $end+1 $end+1 1000]
    validate $l
    list [repStoreRefCount $b] $l [leadSpace $l] [expr {[tailSpace $l]>0}] [repStoreRefCount $l]
} -result [list 2 [irange 0 1000] 0 1 1]

test listrep-2.9.1 {
    Appends to back of large shared list with no free space allocates new
    list with space only at the back - linsert version
} -constraints testlistrep -body {
    set a [freeSpaceNone 1000]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [linsert $b $end+1 1000 1001]
    validate $l
    list [repStoreRefCount $b] $l [leadSpace $l] [expr {[tailSpace $l]>0}] [repStoreRefCount $l]
} -result [list 2 [irange 0 1001] 0 1 1]

test listrep-2.9.2 {
    Appends to back of large shared list with no free space allocates new
    list with space only at the back - lappend version
} -constraints testlistrep -body {
    set a [freeSpaceNone 1000]
    set l [lrange $a $zero end]; # Ensure shared listrep
    lappend l 1000
    validate $l
    list $l [leadSpace $l] [expr {[tailSpace $l]>0}] [repStoreRefCount $l]
} -result [list [irange 0 1000] 0 1 1]

test listrep-2.9.3 {
    Appends to back of large shared list with no free space allocates new
    list with space only at the back - lset version
} -constraints testlistrep -body {
    set a [freeSpaceNone 1000]
    set l [lrange $a $zero end]; # Ensure shared listrep
    lset l $end+1 1000
    validate $l
    list $l [leadSpace $l] [expr {[tailSpace $l]>0}] [repStoreRefCount $l]
} -result [list [irange 0 1000] 0 1 1]

test listrep-2.10 {
    Replacement of elements at front with same number in shared list results
    in a new list store with more space in front than back - lreplace version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lreplace $b $zero $one 10 11]
    validate $l
    list [repStoreRefCount $b] $l [leadSpaceMore $l] [repStoreRefCount $l]
} -result [list 2 {10 11 2 3 4 5 6 7} 1 1]

test listrep-2.10.1 {
    Replacement of elements at front with same number in shared list results
    in a new list store with no extra space - lset version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set l [lrange $a $zero end]; # Ensure shared listrep
    lset l $zero 10
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {10 1 2 3 4 5 6 7} 0 0 1]

test listrep-2.11 {
    Replacement of elements at front with fewer elements in shared list
    results in a new list store with more space in front than back
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lreplace $b $zero $four 10]
    validate $l
    list [repStoreRefCount $b] $l [leadSpaceMore $l] [repStoreRefCount $l]
} -result [list 2 {10 5 6 7} 1 1]

test listrep-2.12 {
    Replacement of elements at front with more elements in shared list
    results in a new spanned list with more space in front
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lreplace $b $zero $one 10 11 12]
    validate $l
    list [repStoreRefCount $b] $l [leadSpaceMore $l] [repStoreRefCount $l]
} -result [list 2 {10 11 12 2 3 4 5 6 7} 1 1]

test listrep-2.13 {
    Replacement of elements in middle with same number in shared list results
    in a new list store with equal space in front and back - lreplace version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lreplace $b $one $two 10 11]
    validate $l
    list [repStoreRefCount $b] $l [spaceEqual $l] [repStoreRefCount $l]
} -result [list 2 {0 10 11 3 4 5 6 7} 1 1]

test listrep-2.13.1 {
    Replacement of elements in middle with same number in shared list results
    in a new list store with exact allocation - lset version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set l [lrange $a $zero end]; # Ensure shared listrep
    lset l $one 10
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {0 10 2 3 4 5 6 7} 0 0 1]

test listrep-2.14 {
    Replacement of elements in middle with fewer elements in shared list
    results in a new list store with equal space
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lreplace $b $one 5 10]
    validate $l
    list [repStoreRefCount $b] $l [spaceEqual $l] [repStoreRefCount $l]
} -result [list 2 {0 10 6 7} 1 1]

test listrep-2.15 {
    Replacement of elements in middle with more elements in shared list
    results in a new spanned list with space in front and back
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lreplace $b $one $two 10 11 12]
    validate $l
    list [repStoreRefCount $b] $l [spaceEqual $l] [repStoreRefCount $l]
} -result [list 2 {0 10 11 12 3 4 5 6 7} 1 1]

test listrep-2.16 {
    Replacement of elements at back with same number in shared list results
    in a new list store with more space in back than front - lreplace version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lreplace $b end-$one $end 10 11]
    validate $l
    list [repStoreRefCount $b] $l [tailSpaceMore $l] [repStoreRefCount $l]
} -result [list 2 {0 1 2 3 4 5 10 11} 1 1]

test listrep-2.16.1 {
    Replacement of elements at back with same number in shared list results
    in a new list store with no extra - lreplace version
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set l [lrange $a $zero end]; # Ensure shared listrep
    lset l $end 10
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {0 1 2 3 4 5 6 10} 0 0 1]

test listrep-2.17 {
    Replacement of elements at back with fewer elements in shared list
    results in a new list store with more space in back than front
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lreplace $b end-$four $end 10]
    validate $l
    list [repStoreRefCount $b] $l [tailSpaceMore $l] [repStoreRefCount $l]
} -result [list 2 {0 1 2 10} 1 1]

test listrep-2.18 {
    Replacement of elements at back with more elements in shared list
    results in a new list store with more space in back than front
} -constraints testlistrep -body {
    set a [freeSpaceNone]
    set b [lrange $a $zero end]; # Ensure shared listrep
    set l [lreplace $b end-$four $end 10]
    validate $l
    list [repStoreRefCount $b] $l [tailSpaceMore $l] [repStoreRefCount $l]
} -result [list 2 {0 1 2 10} 1 1]

#
# listrep-3.* - tests on unshared spanned listreps

test listrep-3.1 {
    Inserts in front of unshared spanned list with room in front should just
    shrink the lead space - linsert version
} -constraints testlistrep -body {
    set l [linsert [freeSpaceBoth] $zero -2 -1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange -2 7] 1 3 1]

test listrep-3.1.1 {
    Inserts in front of unshared spanned list with room in front should just
    shrink the lead space - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $zero -1 -2 -1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange -2 7] 1 3 1]

test listrep-3.2 {
    Inserts in front of unshared spanned list with insufficient room in front
    but enough total freespace should redistribute free space - linsert version
} -constraints testlistrep -body {
    set l [linsert [freeSpaceBoth 8 1 10] $zero -2 -1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange -2 7] 5 4 1]

test listrep-3.2.1 {
    Inserts in front of unshared spanned list with insufficient room in front
    but enough total freespace should redistribute free space - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 8 1 10] $zero -1 -2 -1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange -2 7] 5 4 1]

test listrep-3.3 {
    Inserts in front of unshared spanned list with insufficient total freespace
    should reallocate with equal free space - linsert version
} -constraints testlistrep -body {
    set l [linsert [freeSpaceBoth 8 1 1] $zero -3 -2 -1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange -3 7] 3 2 1]

test listrep-3.3.1 {
    Inserts in front of unshared spanned list with insufficient total freespace
    should reallocate with equal free space - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 8 1 1] $zero -1 -3 -2 -1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange -3 7] 3 2 1]

test listrep-3.4 {
    Inserts at back of unshared spanned list with room at back should not
    reallocate - linsert version
} -constraints testlistrep -body {
    set l [linsert [freeSpaceBoth] $end 8]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 0 8] 3 2 1]

test listrep-3.4.1 {
    Inserts at back of unshared spanned list with room at back should not
    reallocate - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $end+1 $end+1 8 9]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 0 9] 3 1 1]

test listrep-3.4.2 {
    Inserts at back of unshared spanned list with room at back should not
    reallocate - lappend version
} -constraints testlistrep -body {
    set l [freeSpaceBoth]
    lappend l 8 9 10
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 0 10] 3 0 1]

test listrep-3.4.3 {
    Inserts at back of unshared spanned list with room at back should not
    reallocate - lset version
} -constraints testlistrep -body {
    set l [freeSpaceBoth]
    lset l $end+1 8
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 0 8] 3 2 1]

test listrep-3.5 {
    Inserts at back of unshared spanned list with insufficient room in back
    but enough total freespace should redistribute free space - linsert version
} -constraints testlistrep -body {
    set l [linsert [freeSpaceBoth 8 10 1] $end 8 9]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 0 9] 5 4 1]

test listrep-3.5.1 {
    Inserts at back of unshared spanned list with insufficient room in back
    but enough total freespace should redistribute free space - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 8 10 1] $end+1 $end+1 8 9]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 0 9] 5 4 1]

test listrep-3.5.2 {
    Inserts at back of unshared spanned list with insufficient room in back
    but enough total freespace should redistribute free space - lappend version
} -constraints testlistrep -body {
    set l [freeSpaceBoth 8 10 1]
    lappend l 8 9
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 0 9] 5 4 1]

test listrep-3.5.3 {
    Inserts at back of unshared spanned list with insufficient room in back
    but enough total freespace should redistribute free space - lset version
} -constraints testlistrep -body {
    set l [freeSpaceBoth 8 10 0]
    lset l $end+1 8
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 0 8] 5 4 1]

test listrep-3.6 {
    Inserts in back of unshared spanned list with insufficient total freespace
    should reallocate with all *additional* space at back. Note this differs
    from the insert in front case because here we realloc(). - linsert version
} -constraints testlistrep -body {
    set l [linsert [freeSpaceBoth 8 1 1] $end 8 9 10]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 0 10] 1 4 1]

test listrep-3.6.1 {
    Inserts in back of unshared spanned list with insufficient total freespace
    should reallocate with all *additional* space at back. Note this differs
    from the insert in front case because here we realloc() - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 8 1 1] $end+1 $end+1 8 9 10]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 0 10] 1 4 1]

test listrep-3.6.2 {
    Inserts in back of unshared spanned list with insufficient total freespace
    should reallocate with all *additional* space at back. Note this differs
    from the insert in front case because here we realloc() - lappend version
} -constraints testlistrep -body {
    set l [freeSpaceBoth 8 1 1]
    lappend l 8 9 10
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 0 10] 1 4 1]

test listrep-3.6.3 {
    Inserts in back of unshared spanned list with insufficient total freespace
    should reallocate with all *additional* space at back. Note this differs
    from the insert in front case because here we realloc() - lset version
} -constraints testlistrep -body {
    set l [freeSpaceNone]
    lset l $end+1 8
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 0 8] 0 4 1]

test listrep-3.7 {
    Inserts in front half of unshared spanned list with room in front should not
    reallocate and should move front segment
} -constraints testlistrep -body {
    set l [linsert [freeSpaceBoth] $one -2 -1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {0 -2 -1 1 2 3 4 5 6 7} 1 3 1]

test listrep-3.8 {
    Inserts in front half of unshared spanned list with insufficient leading
    space but with enough tail space - linsert version
} -constraints testlistrep -body {
    set l [linsert [freeSpaceBoth 8 1 5] $one -2 -1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {0 -2 -1 1 2 3 4 5 6 7} 1 3 1]

test listrep-3.8.1 {
    Inserts in front half of unshared spanned list with insufficient leading
    space but with enough tail space - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 8 1 5] $one -1 -2 -1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {0 -2 -1 1 2 3 4 5 6 7} 1 3 1]

test listrep-3.9 {
    Inserts in front half of unshared spanned list with sufficient total
    free space - linsert version
} -constraints testlistrep -body {
    set l [linsert [freeSpaceBoth 8 2 2] $one -3 -2 -1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {0 -3 -2 -1 1 2 3 4 5 6 7} 0 1 1]

test listrep-3.9.1 {
    Inserts in front half of unshared spanned list with sufficient total
    free space - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 8 2 2] $one -1 -3 -2 -1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {0 -3 -2 -1 1 2 3 4 5 6 7} 0 1 1]

test listrep-3.10 {
    Inserts in front half of unshared spanned list with insufficient total space.
    Note use of realloc() means new space will be at the back - linsert version
} -constraints testlistrep -body {
    set l [linsert [freeSpaceBoth 8 1 1] $one -3 -2 -1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {0 -3 -2 -1 1 2 3 4 5 6 7} 1 4 1]

test listrep-3.10.1 {
    Inserts in front half of unshared spanned list with insufficient total space.
    Note use of realloc() means new space will be at the back - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 8 1 1] $one -1 -3 -2 -1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {0 -3 -2 -1 1 2 3 4 5 6 7} 1 4 1]

test listrep-3.11 {
    Inserts in back half of unshared spanned list with room in back should not
    reallocate and should move back segment - linsert version
} -constraints testlistrep -body {
    set l [linsert [freeSpaceBoth] $end-$one 8 9]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {0 1 2 3 4 5 6 8 9 7} 3 1 1]

test listrep-3.11.1 {
    Inserts in back half of unshared spanned list with room in back should not
    reallocate and should move back segment - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $end -1 8 9]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {0 1 2 3 4 5 6 8 9 7} 3 1 1]

test listrep-3.12 {
    Inserts in back half of unshared spanned list with insufficient tail
    space but with enough leading space - linsert version
} -constraints testlistrep -body {
    set l [linsert [freeSpaceBoth 8 5 1] $end-$one 8 9]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {0 1 2 3 4 5 6 8 9 7} 3 1 1]

test listrep-3.12.1 {
    Inserts in back half of unshared spanned list with insufficient tail
    space but with enough leading space - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 8 5 1] $end -1 8 9]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {0 1 2 3 4 5 6 8 9 7} 3 1 1]

test listrep-3.13 {
    Inserts in back half of unshared spanned list with sufficient total
    free space - linsert version
} -constraints testlistrep -body {
    set l [linsert [freeSpaceBoth 8 2 2] $end-$one 8 9 10]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {0 1 2 3 4 5 6 8 9 10 7} 0 1 1]

test listrep-3.13.1 {
    Inserts in back half of unshared spanned list with sufficient total
    free space - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 8 2 2] $end -1 8 9 10]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {0 1 2 3 4 5 6 8 9 10 7} 0 1 1]

test listrep-3.14 {
    Inserts in back half of unshared spanned list with insufficient
    total space. Note use of realloc() means new space will be at the
    back - linsert version
} -constraints testlistrep -body {
    set l [linsert [freeSpaceBoth 8 1 1] $end-$one 8 9 10]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {0 1 2 3 4 5 6 8 9 10 7} 1 4 1]

test listrep-3.14.1 {
    Inserts in back half of unshared spanned list with insufficient
    total space. Note use of realloc() means new space will be at the
    back - lrepalce version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 8 1 1] $end -1 8 9 10]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {0 1 2 3 4 5 6 8 9 10 7} 1 4 1]

test listrep-3.15 {
    Deletes from front of small unshared span list results in elements
    moved up front and span removal - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $zero $zero]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list {1 2 3 4 5 6 7} 0 7 0]

test listrep-3.15.1 {
    Deletes from front of small unshared span list results in elements
    moved up front and span removal - lremove version
} -constraints testlistrep -body {
    set l [lremove [freeSpaceBoth] $zero $one]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list {2 3 4 5 6 7} 0 8 0]

test listrep-3.15.2 {
    Deletes from front of small unshared span list results in elements
    moved up front and span removal - lrange version
} -constraints testlistrep -body {
    set l [lrange [freeSpaceBoth] $one $end]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list {1 2 3 4 5 6 7} 0 7 0]

test listrep-3.15.3 {
    Deletes from front of small unshared span list results in elements
    moved up front and span removal - lassign version
} -constraints testlistrep -body {
    set l [lassign [freeSpaceBoth] e]
    validate $l
    list $e $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list 0 {1 2 3 4 5 6 7} 0 7 0]

test listrep-3.15.4 {
    Deletes from front of small unshared span list results in elements
    moved up front and span removal - lpop version
} -constraints testlistrep -body {
    set l [freeSpaceBoth]
    set e [lpop l $zero]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list {1 2 3 4 5 6 7} 0 7 0]

test listrep-3.16 {
    Deletes from front of large unshared span list results in another
    span - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 1000 10 10] $zero $one]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 12 998]
} -result [list [irange 2 999] 12 10 1]

test listrep-3.16.1 {
    Deletes from front of large unshared span list results in another
    span - lremove version
} -constraints testlistrep -body {
    set l [lremove [freeSpaceBoth 1000 10 10] $zero $one]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 12 998]
} -result [list [irange 2 999] 12 10 1]

test listrep-3.16.2 {
    Deletes from front of large unshared span list results in another
    span - lrange version
} -constraints testlistrep -body {
    set l [lrange [freeSpaceBoth 1000 10 10] $two $end]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 12 998]
} -result [list [irange 2 999] 12 10 1]

test listrep-3.16.3 {
    Deletes from front of large unshared span list results in another
    span - lassign version
} -constraints testlistrep -body {
    set l [lassign [freeSpaceBoth 1000 10 10] e]
    validate $l
    list $e $l [leadSpace $l] [tailSpace $l] [hasSpan $l 11 999]
} -result [list 0 [irange 1 999] 11 10 1]

test listrep-3.16.4 {
    Deletes from front of large unshared span list results in another
    span - lpop version
} -constraints testlistrep -body {
    set l [freeSpaceBoth 1000 10 10]
    set e [lpop l $zero]
    validate $l
    list $e $l [leadSpace $l] [tailSpace $l] [hasSpan $l 11 999]
} -result [list 0 [irange 1 999] 11 10 1]

test listrep-3.17 {
    Deletes from back of small unshared span list results in new store
    without span - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $end $end]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list {0 1 2 3 4 5 6} 0 7 0]

test listrep-3.17.1 {
    Deletes from back of small unshared span list results in new store
    without span - lremove version
} -constraints testlistrep -body {
    set l [lremove [freeSpaceBoth] $end]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list {0 1 2 3 4 5 6} 0 7 0]

test listrep-3.17.2 {
    Deletes from back of small unshared span list results in new store
    without span - lrange version
} -constraints testlistrep -body {
    set l [lrange [freeSpaceBoth] $zero $end-1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list {0 1 2 3 4 5 6} 0 7 0]

test listrep-3.17.3 {
    Deletes from back of small unshared span list results in new store
    without span - lpop version
} -constraints testlistrep -body {
    set l [freeSpaceBoth]
    set e [lpop l]
    validate $l
    list $e $l [leadSpace $l] [tailSpace $l] [hasSpan $l]
} -result [list 7 {0 1 2 3 4 5 6} 0 7 0]

test listrep-3.18 {
    Deletes from back of large unshared span list results in another
    span - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 1000 10 10] $end-1 $end]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 10 998]
} -result [list [irange 0 997] 10 12 1]

test listrep-3.18.1 {
    Deletes from back of large unshared span list results in another
    span - lremove version
} -constraints testlistrep -body {
    set l [lremove [freeSpaceBoth 1000 10 10] $end-1 $end]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 10 998]
} -result [list [irange 0 997] 10 12 1]

test listrep-3.18.2 {
    Deletes from back of large unshared span list results in another
    span - lrange version
} -constraints testlistrep -body {
    set l [lrange [freeSpaceBoth 1000 10 10] $zero $end-2]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 10 998]
} -result [list [irange 0 997] 10 12 1]

test listrep-3.18.3 {
    Deletes from back of large unshared span list results in another
    span - lpop version
} -constraints testlistrep -body {
    set l [freeSpaceBoth 1000 10 10]
    set e [lpop l]
    validate $l
    list $e $l [leadSpace $l] [tailSpace $l] [hasSpan $l 10 999]
} -result [list 999 [irange 0 998] 10 11 1]

test listrep-3.19 {
    Deletes from front half of small unshared span list results in
    movement of smaller front segment - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $one $two]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 5 6]
} -result [list {0 3 4 5 6 7} 5 3 1]

test listrep-3.19.1 {
    Deletes from front half of small unshared span list results in
    movement of smaller front segment - lremove version
} -constraints testlistrep -body {
    set l [lremove [freeSpaceBoth] $one $two]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 5 6]
} -result [list {0 3 4 5 6 7} 5 3 1]

test listrep-3.20 {
    Deletes from front half of large unshared span list results in
    movement of smaller front segment - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 1000 10 10] $one $two]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 12 998]
} -result [list [list 0 {*}[irange 3 999]] 12 10 1]

test listrep-3.20.1 {
    Deletes from front half of large unshared span list results in
    movement of smaller front segment - lremove version
} -constraints testlistrep -body {
    set l [lremove [freeSpaceBoth 1000 10 10] $one $two]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 12 998]
} -result [list [list 0 {*}[irange 3 999]] 12 10 1]

test listrep-3.21 {
    Deletes from back half of small unshared span list results in
    movement of smaller back segment - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $end-2 $end-1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 3 6]
} -result [list {0 1 2 3 4 7} 3 5 1]

test listrep-3.21.1 {
    Deletes from back half of small unshared span list results in
    movement of smaller back segment - lremove version
} -constraints testlistrep -body {
    set l [lremove [freeSpaceBoth] $end-2 $end-1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 3 6]
} -result [list {0 1 2 3 4 7} 3 5 1]

test listrep-3.22 {
    Deletes from back half of large unshared span list results in
    movement of smaller back segment - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 1000 10 10] $end-2 $end-1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 10 998]
} -result [list [list {*}[irange 0 996] 999] 10 12 1]

test listrep-3.22.1 {
    Deletes from back half of large unshared span list results in
    movement of smaller back segment - lremove version
} -constraints testlistrep -body {
    set l [lremove [freeSpaceBoth 1000 10 10] $end-2 $end-1]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [hasSpan $l 10 998]
} -result [list [list {*}[irange 0 996] 999] 10 12 1]

test listrep-3.23 {
    Replacement of elements at front with same number elements in unshared
    spanned list is in-place - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $zero $one 10 11]
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {10 11 2 3 4 5 6 7} 3 3]

test listrep-3.23.1 {
    Replacement of elements at front with same number elements in unshared
    spanned list is in-place - lset version
} -constraints testlistrep -body {
    set l [freeSpaceBoth]
    lset l $zero 10
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {10 1 2 3 4 5 6 7} 3 3]

test listrep-3.24 {
    Replacement of elements at front with fewer elements in unshared
    spanned list expands leading space - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $zero $four 10]
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {10 5 6 7} 7 3]

test listrep-3.25 {
    Replacement of elements at front with more elements in unshared
    spanned list with sufficient leading space shrinks leading space
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $zero $one 10 11 12]
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {10 11 12 2 3 4 5 6 7} 2 3]

test listrep-3.26 {
    Replacement of elements at front with more elements in unshared
    spanned list with insufficient leading space but sufficient total
    free space
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 8 1 10] $zero $one 10 11 12 13]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {10 11 12 13 2 3 4 5 6 7} 5 4 1]

test listrep-3.27 {
    Replacement of elements at front in unshared spanned list with insufficient
    total freespace should reallocate with equal free space
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 8 1 1] $zero $one 10 11 12 13 14]
    validate $l
    list $l [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list {10 11 12 13 14 2 3 4 5 6 7} 3 2 1]

test listrep-3.28 {
    Replacement of elements at back with same number of elements in unshared
    spanned list is in-place - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $end-1 $end 10 11]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 2 3 4 5 10 11} 3 3]

test listrep-3.28.1 {
    Replacement of elements at back with same number of elements in unshared
    spanned list is in-place - lset version
} -constraints testlistrep -body {
    set l [freeSpaceBoth]
    lset l $end 10
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 2 3 4 5 6 10} 3 3]

test listrep-3.29 {
    Replacement of elements at back with fewer elements in unshared
    spanned list expands tail space
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $end-2 $end 10]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 2 3 4 10} 3 5]

test listrep-3.30 {
    Replacement of elements at back with more elements in unshared
    spanned list with sufficient tail space shrinks tailspace
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $end-1 $end 10 11 12]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 2 3 4 5 10 11 12} 3 2]

test listrep-3.31 {
    Replacement of elements at back with more elements in unshared spanned list
    with insufficient tail space but enough total free space moves up the span
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 8 2 2] $end-1 $end 10 11 12 13 14]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 2 3 4 5 10 11 12 13 14} 0 1]

test listrep-3.32 {
    Replacement of elements at back with more elements in unshared spanned list
    with insufficient total space reallocates with more room in the tail because
    of realloc()
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 8 1 1] $end-1 $end 10 11 12 13 14]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 2 3 4 5 10 11 12 13 14} 1 4]

test listrep-3.33 {
    Replacement of elements in the middle in an unshared spanned list with
    the same number of elements - lreplace version
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $two $four 10 11 12]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 10 11 12 5 6 7} 3 3]

test listrep-3.33.1 {
    Replacement of elements in the middle in an unshared spanned list with
    the same number of elements - lset version
} -constraints testlistrep -body {
    set l [freeSpaceBoth]
    lset l $two 10
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 10 3 4 5 6 7} 3 3]

test listrep-3.34 {
    Replacement of elements in an unshared spanned list with fewer elements
    in the front half moves the front (smaller) segment
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $two $four 10 11]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 10 11 5 6 7} 4 3]

test listrep-3.35 {
    Replacement of elements in an unshared spanned list with fewer elements
    in the back half moves the tail (smaller) segment
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $end-2 $end-1 10]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 2 3 4 10 7} 3 4]

test listrep-3.36 {
    Replacement of elements in an unshared spanned list with more elements
    when both front and back have room should move the smaller segment
    (front case)
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $one $two 8 9 10]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 8 9 10 3 4 5 6 7} 2 3]

test listrep-3.37 {
    Replacement of elements in an unshared spanned list with more elements
    when both front and back have room should move the smaller segment
    (back case)
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $end-2 $end-1 8 9 10]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 2 3 4 8 9 10 7} 3 2]

test listrep-3.38 {
    Replacement of elements in an unshared spanned list with more elements
    when only front has room
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 8 3 1] $end-1 $end-1 8 9 10]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 1 2 3 4 5 8 9 10 7} 1 1]

test listrep-3.39 {
    Replacement of elements in an unshared spanned list with more elements
    when only back has room
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 8 1 3] $one $one 8 9 10]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 8 9 10 2 3 4 5 6 7} 1 1]

test listrep-3.40 {
    Replacement of elements in an unshared spanned list with more elements
    when neither send has enough room by itself
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth] $one $one 8 9 10 11 12]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 8 9 10 11 12 2 3 4 5 6 7} 1 1]

test listrep-3.41 {
    Replacement of elements in an unshared spanned list with more elements
    when there is not enough free space results in new allocation. The back
    end has more space because of realloc()
} -constraints testlistrep -body {
    set l [lreplace [freeSpaceBoth 8 1 1] $one $one 8 9 10 11 12]
    validate $l
    list $l [leadSpace $l] [tailSpace $l]
} -result [list {0 8 9 10 11 12 2 3 4 5 6 7} 1 5]

#
# 4.* - tests on shared spanned lists

test listrep-4.1 {
    Inserts in front of shared spanned list with used elements in lead space
    creates new list rep with more lead than tail space - linsert version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [linsert $spanl $zero -1]
    validate $l
    list $master $spanl $l [leadSpaceMore $l] [hasSpan $l] [repStoreRefCount $master] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 0 999] [irange 2 997] [list -1 {*}[irange 2 997]] 1 1 2 2 1]

test listrep-4.1.1 {
    Inserts in front of shared spanned list with used elements in lead space
    creates new list rep with more lead than tail space - lreplace version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [lreplace $spanl $zero -1 -2]
    validate $l
    list $master $spanl $l [leadSpaceMore $l] [hasSpan $l] [repStoreRefCount $master] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 0 999] [irange 2 997] [list -2 {*}[irange 2 997]] 1 1 2 2 1]

test listrep-4.2 {
    Inserts in front of shared spanned list with orphaned leading elements
    allocate a new list rep with more lead than tail space - linsert version
    TODO - ideally this should garbage collect the orphans and reuse the lead space
    but that needs a "lprepend" command else the listrep operand is shared and hence
    orphans cannot be freed
} -constraints testlistrep -body {
    set master [freeSpaceLead 1000 100]
    set spanl [lrange $master $two $end-2]
    unset master; # So elements at 0, 1 are not used
    set l [linsert $spanl $zero -1]
    validate $l
    list $spanl $l [sameStore $spanl $l] [leadSpaceMore $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [list -1 {*}[irange 2 997]] 0 1 1 1 1]

test listrep-4.2.1 {
    Inserts in front of shared spanned list with orphaned leading elements
    allocate a new list rep with more lead than tail space - lreplace version
    TODO - ideally this should garbage collect the orphans and reuse the lead space
    but that needs a "lprepend" command else the listrep operand is shared and hence
    orphans cannot be freed
} -constraints testlistrep -body {
    set master [freeSpaceLead 1000 100]
    set spanl [lrange $master $two $end-2]
    unset master; # So elements at 0, 1 are not used
    set l [lreplace $spanl $zero -1 -2]
    validate $l
    list $spanl $l [sameStore $spanl $l] [leadSpaceMore $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [list -2 {*}[irange 2 997]] 0 1 1 1 1]

test listrep-4.3 {
    Inserts in front of shared spanned list where span is at front of used
    space reuses the same list store - linsert version
} -constraints testlistrep -body {
    set master [freeSpaceLead 1000 100]
    set spanl [lrange $master $zero $end-2]
    set l [linsert $spanl $zero -1]
    validate $l
    list $spanl $l [sameStore $spanl $l] [leadSpace $l] [tailSpace $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 0 997] [irange -1 997] 1 99 0 1 3 3]

test listrep-4.3.1 {
    Inserts in front of shared spanned list where span is at front of used
    space reuses the same list store - lreplace version
} -constraints testlistrep -body {
    set master [freeSpaceLead 1000 100]
    set spanl [lrange $master $zero $end-2]
    set l [lreplace $spanl $zero -1 -1]
    validate $l
    list $spanl $l [sameStore $spanl $l] [leadSpace $l] [tailSpace $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 0 997] [irange -1 997] 1 99 0 1 3 3]

test listrep-4.4 {
    Inserts in front of shared spanned list where span is at front of used
    space allocates new listrep if lead space insufficient even if total free space
    is sufficient. New listrep should have more lead space than tail space.
    - linsert version
} -constraints testlistrep -body {
    set master [freeSpaceBoth 1000 2]
    set spanl [lrange $master $zero $end-2]
    set l [linsert $spanl $zero -3 -2 -1]
    validate $l
    list $spanl $l [sameStore $spanl $l] [leadSpaceMore $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 0 997] [irange -3 997] 0 1 1 2 1]

test listrep-4.4.1 {
    Inserts in front of shared spanned list where span is at front of used
    space allocates new listrep if lead space insufficient even if total free space
    is sufficient. New listrep should have more lead space than tail space.
    - lreplace version
} -constraints testlistrep -body {
    set master [freeSpaceBoth 1000 2]
    set spanl [lrange $master $zero $end-2]
    set l [lreplace $spanl $zero -1 -3 -2 -1]
    validate $l
    list $spanl $l [sameStore $spanl $l] [leadSpaceMore $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 0 997] [irange -3 997] 0 1 1 2 1]

test listrep-4.5 {
    Inserts in back of shared spanned list where span is at end of used space
    still allocates a new listrep and trailing space is more than leading space
    - linsert version
} -constraints testlistrep -body {
    set master [freeSpaceBoth 1000 2]
    set spanl [lrange $master $two $end]
    set l [linsert $spanl $end 1000]
    validate $l
    list $spanl $l [sameStore $spanl $l] [tailSpaceMore $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 999] [irange 2 1000] 0 1 1 2 1]

test listrep-4.5.1 {
    Inserts in back of shared spanned list where span is at end of used space
    still allocates a new listrep and trailing space is more than leading space
    - lreplace version
} -constraints testlistrep -body {
    set master [freeSpaceBoth 1000 2]
    set spanl [lrange $master $two $end]
    set l [lreplace $spanl $end+1 $end+1 1000]
    validate $l
    list $spanl $l [sameStore $spanl $l] [tailSpaceMore $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 999] [irange 2 1000] 0 1 1 2 1]

test listrep-4.5.2 {
    Inserts in back of shared spanned list where span is at end of used space
    still allocates a new listrep and trailing space is more than leading space
    - lappend version
} -constraints testlistrep -body {
    set master [freeSpaceBoth 1000 2]
    set l [lrange $master $two $end]
    lappend l 1000
    validate $l
    list $l [sameStore $master $l] [tailSpaceMore $l] [hasSpan $l] [repStoreRefCount $l]
} -result [list  [irange 2 1000] 0 1 1 1]

test listrep-4.5.3 {
    Inserts in back of shared spanned list where span is at end of used space
    still allocates a new listrep and trailing space is more than leading space
    - lset version
} -constraints testlistrep -body {
    set master [freeSpaceBoth 1000 2]
    set l [lrange $master $two $end]
    lset l $end+1 1000
    validate $l
    list $l [sameStore $master $l] [tailSpaceMore $l] [hasSpan $l] [repStoreRefCount $l]
} -result [list  [irange 2 1000] 0 1 1 1]


test listrep-4.6 {
    Inserts in middle of shared spanned list allocates a new listrep with equal
    lead and tail space - linsert version
} -constraints testlistrep -body {
    set master [freeSpaceBoth 1000 2]
    set spanl [lrange $master $two $end-2]
    set i 200
    set l [linsert $spanl $i 1000]
    validate $l
    list $spanl $l [sameStore $spanl $l] [spaceEqual $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [concat [irange 2 201] 1000 [irange 202 997]] 0 1 1 2 1]

test listrep-4.6.1 {
    Inserts in middle of shared spanned list allocates a new listrep with equal
    lead and tail space - lreplace version
} -constraints testlistrep -body {
    set master [freeSpaceBoth 1000 2]
    set spanl [lrange $master $two $end-2]
    set i 200
    set l [lreplace $spanl $i -1 1000]
    validate $l
    list $spanl $l [sameStore $spanl $l] [spaceEqual $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [concat [irange 2 201] 1000 [irange 202 997]] 0 1 1 2 1]

test listrep-4.7 {
    Deletes from front of shared spanned list do not create a new allocation
    - lreplace version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [lreplace $spanl $zero $one]
    validate $l
    list $spanl $l [sameStore $spanl $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [irange 4 997] 1 1 3 3]

test listrep-4.7.1 {
    Deletes from front of shared spanned list do not create a new allocation
    - lremove version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [lremove $spanl $zero $one]
    validate $l
    list $spanl $l [sameStore $spanl $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [irange 4 997] 1 1 3 3]

test listrep-4.7.2 {
    Deletes from front of shared spanned list do not create a new allocation
    - lrange version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [lrange $spanl $two $end]
    validate $l
    list $spanl $l [sameStore $spanl $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [irange 4 997] 1 1 3 3]

test listrep-4.7.3 {
    Deletes from front of shared spanned list do not create a new allocation
    - lassign version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [lassign $spanl e]
    validate $l
    list $e $spanl $l [sameStore $spanl $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list 2 [irange 2 997] [irange 3 997] 1 1 3 3]

test listrep-4.7.4 {
    Deletes from front of shared spanned list do not create a new allocation
    - lpop version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set l [lrange $master $two $end-2]
    set e [lpop l $zero]
    validate $l
    list $e $l [sameStore $master $l] [hasSpan $l] [repStoreRefCount $l]
} -result [list 2 [irange 3 997] 1 1 2]

test listrep-4.8 {
    Deletes from end of shared spanned list do not create a new allocation
    - lreplace version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [lreplace $spanl $end-1 $end]
    validate $l
    list $spanl $l [sameStore $spanl $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [irange 2 995] 1 1 3 3]

test listrep-4.8.1 {
    Deletes from end of shared spanned list do not create a new allocation
    - lremove version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [lremove $spanl $end-1 $end]
    validate $l
    list $spanl $l [sameStore $spanl $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [irange 2 995] 1 1 3 3]

test listrep-4.8.2 {
    Deletes from end of shared spanned list do not create a new allocation
    - lrange version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [lrange $spanl 0 $end-2]
    validate $l
    list $spanl $l [sameStore $spanl $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [irange 2 995] 1 1 3 3]

test listrep-4.8.3 {
    Deletes from end of shared spanned list do not create a new allocation
    - lpop version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set l [lrange $master $two $end-2]
    set e [lpop l]
    validate $l
    list $e $l [sameStore $master $l] [hasSpan $l] [repStoreRefCount $l]
} -result [list 997 [irange 2 996] 1 1 2]

test listrep-4.9 {
    Deletes from middle of shared spanned list creates a new allocation with
    equal free space at front and back - lreplace version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set i 500
    set l [lreplace $spanl $i $i]
    validate $l
    list $spanl $l [sameStore $spanl $l] [hasSpan $l] [spaceEqual $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [concat [irange 2 501] [irange 503 997]] 0 1 1 2 1]

test listrep-4.9.1 {
    Deletes from middle of shared spanned list creates a new allocation with
    equal free space at front and back - lremove version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set i 500
    set l [lremove $spanl $i $i]
    validate $l
    list $spanl $l [sameStore $spanl $l] [hasSpan $l] [spaceEqual $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [concat [irange 2 501] [irange 503 997]] 0 1 1 2 1]

test listrep-4.9.2 {
    Deletes from middle of shared spanned list creates a new allocation with
    equal free space at front and back - lpop version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set l [lrange $master $two $end-2]
    set i 500
    set e [lpop l $i]
    validate $l
    list $e $l [sameStore $master $l] [hasSpan $l] [spaceEqual $l] [repStoreRefCount $l]
} -result [list 502 [concat [irange 2 501] [irange 503 997]] 0 1 1 1]

test listrep-4.10 {
    Replacements with same number of elements at front of shared spanned list
    create a new allocation with more space in front - lreplace version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [lreplace $spanl $zero $one -2 -1]
    validate $l
    list $spanl $l [sameStore $spanl $l] [leadSpaceMore $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [concat {-2 -1} [irange 4 997]] 0 1 1 2 1]

test listrep-4.10.1 {
    Replacements with same number of elements at front of shared spanned list
    create a new allocation with exact size
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set l [lrange $master $two $end-2]
    lset l $zero -1
    validate $l
    list $l [sameStore $master $l] [hasSpan $l] [repStoreRefCount $l]
} -result [list [concat {-1} [irange 3 997]] 0 0 1]

test listrep-4.11 {
    Replacements with fewer elements at front of shared spanned list
    create a new allocation with more space in front
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [lreplace $spanl $zero $one -1]
    validate $l
    list $spanl $l [sameStore $spanl $l] [leadSpaceMore $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [concat {-1} [irange 4 997]] 0 1 1 2 1]

test listrep-4.12 {
    Replacements with more elements at front of shared spanned list
    create a new allocation with more space in front
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [lreplace $spanl $zero $one -3 -2 -1]
    validate $l
    list $spanl $l [sameStore $spanl $l] [leadSpaceMore $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [concat {-3 -2 -1} [irange 4 997]] 0 1 1 2 1]

test listrep-4.13 {
    Replacements with same number of elements at back of shared spanned list
    create a new allocation with more space in back - lreplace version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [lreplace $spanl $end-1 $end 1000 1001]
    validate $l
    list $spanl $l [sameStore $spanl $l] [tailSpaceMore $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [concat [irange 2 995] {1000 1001}] 0 1 1 2 1]

test listrep-4.13.1 {
    Replacements with same number of elements at back of shared spanned list
    create a new exact allocation with no span - lset version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set l [lrange $master $two $end-2]
    lset l $end 1000
    validate $l
    list $l [sameStore $master $l] [tailSpace $l] [hasSpan $l] [repStoreRefCount $l]
} -result [list [concat [irange 2 996] {1000}] 0 0 0 1]

test listrep-4.14 {
    Replacements with fewer elements at back of shared spanned list
    create a new allocation with more space in back
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [lreplace $spanl $end-1 $end 1000]
    validate $l
    list $spanl $l [sameStore $spanl $l] [tailSpaceMore $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [concat [irange 2 995] {1000}] 0 1 1 2 1]

test listrep-4.15 {
    Replacements with more elements at back of shared spanned list
    create a new allocation with more space in back
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [lreplace $spanl $end-1 $end 1000 1001 1002]
    validate $l
    list $spanl $l [sameStore $spanl $l] [tailSpaceMore $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [concat [irange 2 995] {1000 1001 1002}] 0 1 1 2 1]

test listrep-4.16 {
    Replacements with same number of elements in middle of shared spanned list
    create a new allocation with equal lead and tail sapce
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [lreplace $spanl $one $two -2 -1]
    validate $l
    list $spanl $l [sameStore $spanl $l] [spaceEqual $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [concat {2 -2 -1} [irange 5 997]] 0 1 1 2 1]

test listrep-4.16.1 {
    Replacements with same number of elements in middle of shared spanned list
    create a new exact allocation - lset version
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set l [lrange $master $two $end-2]
    lset l $one -2
    validate $l
    list $l [sameStore $master $l] [hasSpan $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [concat {2 -2} [irange 4 997]] 0 0 0 1]

test listrep-4.17 {
    Replacements with fewer elements in middle of shared spanned list
    create a new allocation with equal lead and tail sapce
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [lreplace $spanl $end-2 $end-1 1000]
    validate $l
    list $spanl $l [sameStore $spanl $l] [spaceEqual $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [concat [irange 2 994] {1000 997}] 0 1 1 2 1]

test listrep-4.18 {
    Replacements with more elements in middle of shared spanned list
    create a new allocation with equal lead and tail sapce
} -constraints testlistrep -body {
    set master [freeSpaceNone 1000]
    set spanl [lrange $master $two $end-2]
    set l [lreplace $spanl $end-2 $end-1 1000 1001 1002]
    validate $l
    list $spanl $l [sameStore $spanl $l] [spaceEqual $l] [hasSpan $l] [repStoreRefCount $spanl] [repStoreRefCount $l]
} -result [list [irange 2 997] [concat [irange 2 994] {1000 1001 1002 997}] 0 1 1 2 1]

# 5.* - tests on shared Tcl_Obj
# Tests when Tcl_Obj is shared but listrep is not. This is to ensure that
# checks for shared values check the Tcl_Obj reference counts in addition to
# the list internal representation reference counts. Probably some or all
# cases are already covered elsewhere but easier to just test than look.
test listrep-5.1 {
    Verify that operation on a shared Tcl_Obj with a single-ref, spanless
    list representation only modifies the target object - lappend version
} -constraints testlistrep -body {
    set l [freeSpaceNone]
    set l2 $l
    set same [sameStore $l $l2]
    lappend l 8
    list $same $l $l2 [sameStore $l $l2]
} -result [list 1 [irange 0 8] [irange 0 7] 0]

test listrep-5.1.1 {
    Verify that operation on a shared Tcl_Obj with a single-ref, spanless
    list representation only modifies the target object - lset version
} -constraints testlistrep -body {
    set l [freeSpaceNone]
    set l2 $l
    set same [sameStore $l $l2]
    lset l $end+1 8
    list $same $l $l2 [sameStore $l $l2]
} -result [list 1 [irange 0 8] [irange 0 7] 0]

test listrep-5.1.2 {
    Verify that operation on a shared Tcl_Obj with a single-ref, spanless
    list representation only modifies the target object - lpop version
} -constraints testlistrep -body {
    set l [freeSpaceNone]
    set l2 $l
    set same [sameStore $l $l2]
    lpop l
    list $same $l $l2 [sameStore $l $l2] [hasSpan $l]
} -result [list 1 [irange 0 6] [irange 0 7] 0 0]

test listrep-5.2 {
    Verify that operation on a shared Tcl_Obj with a single-ref, spanned
    list representation only modifies the target object - lappend version
} -constraints testlistrep -body {
    set l [freeSpaceBoth 1000 10 10]
    set l2 $l
    set same [sameStore $l $l2]
    lappend l 1000
    list $same $l $l2 [sameStore $l $l2] [hasSpan $l] [hasSpan $l2]
} -result [list 1 [irange 0 1000] [irange 0 999] 0 1 1]

test listrep-5.2.1 {
    Verify that operation on a shared Tcl_Obj with a single-ref, spanned
    list representation only modifies the target object - lset version
} -constraints testlistrep -body {
    set l [freeSpaceBoth 1000 10 10]
    set l2 $l
    set same [sameStore $l $l2]
    lset l $end+1 1000
    list $same $l $l2 [sameStore $l $l2] [hasSpan $l] [hasSpan $l2]
} -result [list 1 [irange 0 1000] [irange 0 999] 0 1 1]

test listrep-5.2.2 {
    Verify that operation on a shared Tcl_Obj with a single-ref, spanned
    list representation only modifies the target object - lpop version
} -constraints testlistrep -body {
    set l [freeSpaceNone 1000]
    set l2 $l
    set same [sameStore $l $l2]
    lpop l
    list $same $l $l2 [sameStore $l $l2] [hasSpan $l] [hasSpan $l2]
} -result [list 1 [irange 0 998] [irange 0 999] 1 1 0]

#
# 6.* - tests when lists contain zombies.
# The list implementation does lazy freeing in some cases so the list store
# contain Tcl_Obj's that are not actually referenced by any list (zombies).
# These are to be freed next time the list store is modified by a list
# operation as long as it is no longer shared.
test listrep-6.1 {
    Verify that zombies are freed up - linsert at front
} -constraints testlistrep -body {
    set l [zombieSample 200 10 10]
    set addr [storeAddress $l]
    # set l {} is for reference counts to drop to 1
    set l [linsert $l[set l {}] $zero -1]
    list $l [expr {$addr == [storeAddress $l]}] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [list -1 {*}[irange 10 209]] 1 9 10 1]

test listrep-6.1.1 {
    Verify that zombies are freed up - linsert in middle
} -constraints testlistrep -body {
    set l [zombieSample 200 10 10]
    set addr [storeAddress $l]
    # set l {} is for reference counts to drop to 1
    set l [linsert $l[set l {}] $one -1]
    list $l [expr {$addr == [storeAddress $l]}] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [list 10 -1 {*}[irange 11 209]] 1 9 10 1]

test listrep-6.1.2 {
    Verify that zombies are freed up - linsert at end
} -constraints testlistrep -body {
    set l [zombieSample 200 10 10]
    set addr [storeAddress $l]
    # set l {} is for reference counts to drop to 1
    set l [linsert $l[set l {}] $end 210]
    list $l [expr {$addr == [storeAddress $l]}] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 10 210] 1 10 9 1]

test listrep-6.2 {
    Verify that zombies are freed up - lrange version (whole)
} -constraints testlistrep -body {
    set l [zombieSample 200 10 10]
    set addr [storeAddress $l]
    # set l {} is for reference counts to drop to 1
    set l [lrange $l[set l {}] $zero $end]
    list $l [expr {$addr == [storeAddress $l]}] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 10 209] 1 10 10 1]

test listrep-6.2.1 {
    Verify that zombies are freed up - lrange version (subrange)
} -constraints testlistrep -body {
    set l [zombieSample 200 10 10]
    set addr [storeAddress $l]
    # set l {} is for reference counts to drop to 1
    set l [lrange $l[set l {}] $one $end-1]
    list $l [expr {$addr == [storeAddress $l]}] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 11 208] 1 11 11 1]

test listrep-6.3 {
    Verify that zombies are freed up - lassign version
} -constraints testlistrep -body {
    set l [zombieSample 200 10 10]
    set addr [storeAddress $l]
    # set l {} is for reference counts to drop to 1
    set l [lassign $l[set l {}] e]
    list $e $l [expr {$addr == [storeAddress $l]}] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 10 [irange 11 209] 1 11 10 1]

test listrep-6.4 {
    Verify that zombies are freed up - lremove version (front)
} -constraints testlistrep -body {
    set l [zombieSample 200 10 10]
    set addr [storeAddress $l]
    # set l {} is for reference counts to drop to 1
    set l [lremove $l[set l {}] $zero]
    list $l [expr {$addr == [storeAddress $l]}] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 11 209] 1 11 10 1]

test listrep-6.4.1 {
    Verify that zombies are freed up - lremove version (back)
} -constraints testlistrep -body {
    set l [zombieSample 200 10 10]
    set addr [storeAddress $l]
    # set l {} is for reference counts to drop to 1
    set l [lremove $l[set l {}] $end]
    list $l [expr {$addr == [storeAddress $l]}] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 10 208] 1 10 11 1]

test listrep-6.5 {
    Verify that zombies are freed up - lreplace at front
} -constraints testlistrep -body {
    set l [zombieSample 200 10 10]
    set addr [storeAddress $l]
    # set l {} is for reference counts to drop to 1
    set l [lreplace $l[set l {}] $zero $one -3 -2 -1]
    list $l [expr {$addr == [storeAddress $l]}] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [list -3 -2 -1 {*}[irange 12 209]] 1 9 10 1]

test listrep-6.5.1 {
    Verify that zombies are freed up - lreplace at back
} -constraints testlistrep -body {
    set l [zombieSample 200 10 10]
    set addr [storeAddress $l]
    # set l {} is for reference counts to drop to 1
    set l [lreplace $l[set l {}] $end-1 $end -1 -2 -3]
    list $l [expr {$addr == [storeAddress $l]}] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [list {*}[irange 10 207] -1 -2 -3] 1 10 9 1]

test listrep-6.6 {
    Verify that zombies are freed up - lappend
} -constraints testlistrep -body {
    set l [zombieSample 200 10 10]
    set addr [storeAddress $l]
    lappend l 210
    list $l [expr {$addr == [storeAddress $l]}] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 10 210] 1 10 9 1]

test listrep-6.7 {
    Verify that zombies are freed up - lpop version (front)
} -constraints testlistrep -body {
    set l [zombieSample 200 10 10]
    set addr [storeAddress $l]
    set e [lpop l $zero]
    list $e $l [expr {$addr == [storeAddress $l]}] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 10 [irange 11 209] 1 11 10 1]

test listrep-6.7.1 {
    Verify that zombies are freed up - lpop version (back)
} -constraints testlistrep -body {
    set l [zombieSample 200 10 10]
    set addr [storeAddress $l]
    set e [lpop l]
    list $e $l [expr {$addr == [storeAddress $l]}] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list 209 [irange 10 208] 1 10 11 1]

test listrep-6.8 {
    Verify that zombies are freed up - lset version
} -constraints testlistrep -body {
    set l [zombieSample 200 10 10]
    set addr [storeAddress $l]
    lset l $zero -1
    list $l [expr {$addr == [storeAddress $l]}] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [list -1 {*}[irange 11 209]] 1 10 10 1]

test listrep-6.8.1 {
    Verify that zombies are freed up - lset version (back)
} -constraints testlistrep -body {
    set l [zombieSample 200 10 10]
    set addr [storeAddress $l]
    lset l $end+1 210
    list $l [expr {$addr == [storeAddress $l]}] [leadSpace $l] [tailSpace $l] [repStoreRefCount $l]
} -result [list [irange 10 210] 1 10 9 1]


# All done
::tcltest::cleanupTests

return