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require 'minitest/autorun'
require 'kpeg'
require 'stringio'
class TestKPeg < Minitest::Test
def assert_match(m, str)
assert_kind_of KPeg::MatchString, m
assert_equal str, m.string
end
def test_dot
gram = KPeg.grammar do |g|
g.root = g.dot
end
assert_match KPeg.match("q", gram), "q"
end
def test_str
gram = KPeg.grammar do |g|
g.root = g.str("hello")
end
assert_match KPeg.match("hello", gram), "hello"
assert_nil KPeg.match("vador", gram)
end
def test_reg
gram = KPeg.grammar do |g|
g.root = g.reg(/[0-9]/)
end
assert_match KPeg.match("3", gram), "3"
end
def test_char_range
gram = KPeg.grammar do |g|
g.root = g.range('0', '9')
end
assert_match KPeg.match("3", gram), "3"
end
def test_any
gram = KPeg.grammar do |g|
g.root = g.any g.str("hello"), g.str("chicken")
end
assert_match KPeg.match("hello", gram), "hello"
assert_match KPeg.match("chicken", gram), "chicken"
assert_nil KPeg.match("vador", gram)
end
def test_maybe
gram = KPeg.grammar do |g|
g.root = g.maybe g.str("hello")
end
m = KPeg.match "hello", gram
assert_kind_of KPeg::Match, m
assert_equal 1, m.matches.size
assert_match m.matches[0], "hello"
m = KPeg.match "surprise", gram
assert_kind_of KPeg::Match, m
assert_equal 0, m.matches.size
end
def test_many
gram = KPeg.grammar do |g|
g.root = g.many g.str("run")
end
m = KPeg.match "runrunrun", gram
assert_kind_of KPeg::Match, m
assert_equal 3, m.matches.size
m.matches.each do |sm|
assert_match sm, "run"
end
assert_nil KPeg.match("vador", gram)
end
def test_kleene
gram = KPeg.grammar do |g|
g.root = g.kleene g.str("run")
end
m = KPeg.match "runrunrun", gram
assert_kind_of KPeg::Match, m
assert_equal 3, m.matches.size
m.matches.each do |sm|
assert_match sm, "run"
end
m = KPeg.match "chicken", gram
assert_kind_of KPeg::Match, m
assert_equal 0, m.matches.size
end
def test_multiple
gram = KPeg.grammar do |g|
g.root = g.multiple g.str("run"), 2, 4
end
m = KPeg.match "runrun", gram
assert_kind_of KPeg::Match, m
assert_equal 2, m.matches.size
m.matches.each do |sm|
assert_match sm, "run"
end
m = KPeg.match "runrunrun", gram
assert_kind_of KPeg::Match, m
assert_equal 3, m.matches.size
m.matches.each do |sm|
assert_match sm, "run"
end
m = KPeg.match "runrunrunrun", gram
assert_kind_of KPeg::Match, m
assert_equal 4, m.matches.size
m.matches.each do |sm|
assert_match sm, "run"
end
assert_nil KPeg.match("run", gram)
assert_nil KPeg.match("runrunrunrunrun", gram)
assert_nil KPeg.match("vador", gram)
end
def test_seq
gram = KPeg.grammar do |g|
g.root = g.seq g.str("hello"), g.str(", world")
end
m = KPeg.match "hello, world", gram
assert_kind_of KPeg::Match, m
assert_match m.matches[0], "hello"
assert_match m.matches[1], ", world"
assert_equal m.value, ["hello", ", world"]
assert_nil KPeg.match("vador", gram)
assert_nil KPeg.match("hello, vador", gram)
end
def test_andp
gram = KPeg.grammar do |g|
g.root = g.seq g.andp(g.str("h")), g.str("hello")
end
m = KPeg.match "hello", gram
assert_equal m.matches.size, 2
assert_match m.matches[0], ""
assert_match m.matches[1], "hello"
end
def test_notp
gram = KPeg.grammar do |g|
g.root = g.seq g.notp(g.str("g")), g.str("hello")
end
m = KPeg.match "hello", gram
assert_equal m.matches.size, 2
assert_match m.matches[0], ""
assert_match m.matches[1], "hello"
end
def test_ref
gram = KPeg.grammar do |g|
g.greeting = g.str("hello")
g.root = g.ref "greeting"
end
m = KPeg.match "hello", gram
assert_match m, "hello"
end
def test_invoke
gram = KPeg.grammar do |g|
g.greeting = g.str("hello")
g.root = g.invoke "greeting"
end
m = KPeg.match "hello", gram
assert_match m, "hello"
end
def test_foreign_ref
g1 = KPeg.grammar do |g|
g.greeting = "hello"
end
g2 = KPeg.grammar do |g|
g.root = g.ref("greeting", g1)
end
m = KPeg.match "hello", g2
assert_match m, "hello"
end
def test_foreign_ref_with_ref
g1 = KPeg.grammar do |g|
g.name = ", evan"
g.greeting = g.seq("hello", :name)
end
g2 = KPeg.grammar do |g|
g.root = g.ref("greeting", g1)
end
m = KPeg.match "hello, evan", g2
assert_match m.matches[0], "hello"
assert_match m.matches[1], ", evan"
end
def test_tag_with_name
gram = KPeg.grammar do |g|
g.root = g.seq(" ", g.t("hello", "greeting"))
end
m = KPeg.match " hello", gram
assert_equal 2, m.matches.size
tag = m.matches[1]
assert_kind_of KPeg::Tag, tag.op
assert_equal 1, tag.matches.size
assert_match tag.matches[0], "hello"
# show that tag influences the value of the sequence
assert_equal m.value, "hello"
end
def test_tag_without_name
gram = KPeg.grammar do |g|
g.root = g.seq(" ", g.t("hello"))
end
m = KPeg.match " hello", gram
assert_equal m.value, "hello"
end
def test_action
gram = KPeg.grammar do |g|
g.root = g.seq("hello", g.action("b + c"))
end
m = KPeg.match "hello", gram
assert_equal 2, m.matches.size
assert_match m.matches[0], "hello"
action = m.matches[1]
assert_equal action.op.action, "b + c"
end
def test_naming
gram = KPeg.grammar do |g|
g.greeting = g.str("hello")
g.root = g.greeting
end
m = KPeg.match "hello", gram
assert_match m, "hello"
end
def test_matching_curly
gram = KPeg.grammar do |g|
g.curly = g.seq("{", g.kleene(g.any(/[^{}]+/, :curly)), "}")
g.root = :curly
end
m = KPeg.match "{ hello }", gram
assert_match m.matches[0], "{"
assert_match m.matches[1].matches[0], " hello "
assert_match m.matches[2], "}"
parc = KPeg::Parser.new "{ foo { bar } }", gram
m = parc.parse
assert_equal "{ foo { bar } }", m.total_string
parc = KPeg::Parser.new "{ foo {\nbar }\n }", gram
m = parc.parse
assert_equal "{ foo {\nbar }\n }", m.total_string
end
def test_collect
gram = KPeg.grammar do |g|
g.root = g.collect(g.many(/[a-z]/))
end
m = KPeg.match "hellomatch", gram
assert_equal "hellomatch", m.value
end
def test_memoization
gram = KPeg.grammar do |g|
g.one = g.str("1")
g.two = g.str("2")
g.root = g.any(
[:one, "-", :two],
[:one, "+", :two]
)
end
parser = KPeg::Parser.new "1+2", gram
m = parser.parse
assert_equal 3, m.matches.size
assert_match m.matches[0], "1"
assert_match m.matches[1], "+"
assert_match m.matches[2], "2"
one = gram.find("one")
two = gram.find("two")
# We try 1 twice
assert_equal 2, parser.memoizations[one][0].uses
# but we only get as far as 2 once
assert_equal 1, parser.memoizations[two][2].uses
end
def test_left_recursion
gram = KPeg.grammar do |g|
g.num = g.reg(/[0-9]/)
g.expr = g.any [:expr, "-", :num], :num
g.root = g.expr
end
parser = KPeg::Parser.new "1-2-3", gram
m = parser.parse
assert_equal 3, m.matches.size
left = m.matches[0]
assert_equal 3, left.matches.size
assert_match left.matches[0], "1"
assert_match left.matches[1], "-"
assert_match left.matches[2], "2"
assert_match m.matches[1], "-"
assert_match m.matches[2], "3"
parser = KPeg::Parser.new "hello", gram
m = parser.parse
assert_nil m
end
def test_math_grammar
gram = KPeg.grammar do |g|
g.num = '0'..'9'
g.term = g.seq(:term, "+", :term) \
| g.seq(:term, "-", :term) \
| :fact
g.fact = g.seq(:fact, "*", :fact) \
| g.seq(:fact, "/", :fact) \
| :num
g.root = g.term
end
sub = KPeg.match "4*3-8/9", gram
mul = sub.matches[0]
div = sub.matches[2]
assert_match mul.matches[0], "4"
assert_match mul.matches[1], "*"
assert_match mul.matches[2], "3"
assert_match sub.matches[1], "-"
assert_match div.matches[0], "8"
assert_match div.matches[1], "/"
assert_match div.matches[2], "9"
end
def test_calc
vars = {}
gram = KPeg.grammar do |g|
g.spaces = /\s*/
g.var = 'a'..'z'
g.num = g.lit(/[0-9]+/) { |i| i.to_i }
g.pri = g.seq(:spaces, :var) { |s,v| vars[v] } \
| g.seq(:spaces, :num) { |s,n| n } \
| g.seq('(', :expr, ')') { |_,e,_| e }
g.mul = g.seq(:mul, "*", :pri) { |x,_,y| x * y } \
| g.seq(:mul, "/", :pri) { |x,_,y| x / y } \
| :pri
g.add = g.seq(:add, "+", :mul) { |x,_,y| x + y } \
| g.seq(:add, "-", :mul) { |x,_,y| x - y } \
| :mul
g.expr = g.seq(:var, "=", :expr) { |v,_,e| vars[v] = e } \
| :add
g.root = g.seq(g.kleene(:expr), :spaces) { |e,_| e }
end
m = KPeg.match "3+4*5", gram
assert_equal 23, m.value
m = KPeg.match "x=2", gram
assert_equal 2, m.value
m = KPeg.match "x=x*7", gram
assert_equal 14, m.value
end
end
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