1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
|
# frozen_string_literal: false
require 'test/unit'
require 'objspace'
class TestStringMemory < Test::Unit::TestCase
def capture_allocations(klass)
allocations = []
EnvUtil.without_gc do
GC.start
generation = GC.count
ObjectSpace.trace_object_allocations do
yield
ObjectSpace.each_object(klass) do |instance|
allocations << instance if ObjectSpace.allocation_generation(instance) == generation
end
end
return allocations.map do |instance|
[
ObjectSpace.allocation_sourcefile(instance),
ObjectSpace.allocation_sourceline(instance),
instance.class,
instance,
]
end.select do |path,|
# drop strings not created in this file
# (the parallel testing framework may create strings in a separate thread)
path == __FILE__
end
end
end
def test_byteslice_prefix
string = ("a" * 100_000).freeze
allocations = capture_allocations(String) do
string.byteslice(0, 50_000)
end
assert_equal 1, allocations.size, "One object allocation is expected, but allocated: #{ allocations.inspect }"
end
def test_byteslice_postfix
string = ("a" * 100_000).freeze
allocations = capture_allocations(String) do
string.byteslice(50_000, 100_000)
end
assert_equal 1, allocations.size, "One object allocation is expected, but allocated: #{ allocations.inspect }"
end
def test_byteslice_postfix_twice
string = ("a" * 100_000).freeze
allocations = capture_allocations(String) do
string.byteslice(50_000, 100_000).byteslice(25_000, 50_000)
end
assert_equal 2, allocations.size, "Two object allocations are expected, but allocated: #{ allocations.inspect }"
end
end
|
