1 // Copyright 2020 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #ifndef V8_INTL_SUPPORT
6 #error Internationalization is expected to be enabled.
7 #endif // V8_INTL_SUPPORT
8
9 #include "src/objects/js-segments.h"
10
11 #include <map>
12 #include <memory>
13 #include <string>
14
15 #include "src/execution/isolate.h"
16 #include "src/heap/factory.h"
17 #include "src/objects/intl-objects.h"
18 #include "src/objects/js-segment-iterator.h"
19 #include "src/objects/js-segmenter-inl.h"
20 #include "src/objects/js-segments-inl.h"
21 #include "src/objects/managed.h"
22 #include "src/objects/objects-inl.h"
23 #include "unicode/brkiter.h"
24
25 namespace v8 {
26 namespace internal {
27
28 // ecma402 #sec-createsegmentsobject
Create(Isolate * isolate,Handle<JSSegmenter> segmenter,Handle<String> string)29 MaybeHandle<JSSegments> JSSegments::Create(Isolate* isolate,
30 Handle<JSSegmenter> segmenter,
31 Handle<String> string) {
32 icu::BreakIterator* break_iterator =
33 segmenter->icu_break_iterator().raw()->clone();
34 DCHECK_NOT_NULL(break_iterator);
35
36 Handle<Managed<icu::UnicodeString>> unicode_string =
37 Intl::SetTextToBreakIterator(isolate, string, break_iterator);
38 Handle<Managed<icu::BreakIterator>> managed_break_iterator =
39 Managed<icu::BreakIterator>::FromRawPtr(isolate, 0, break_iterator);
40
41 // 1. Let internalSlotsList be « [[SegmentsSegmenter]], [[SegmentsString]] ».
42 // 2. Let segments be ! ObjectCreate(%Segments.prototype%, internalSlotsList).
43 Handle<Map> map(isolate->native_context()->intl_segments_map(), isolate);
44 Handle<JSObject> result = isolate->factory()->NewJSObjectFromMap(map);
45
46 Handle<JSSegments> segments = Handle<JSSegments>::cast(result);
47 segments->set_flags(0);
48
49 // 3. Set segments.[[SegmentsSegmenter]] to segmenter.
50 segments->set_icu_break_iterator(*managed_break_iterator);
51 segments->set_granularity(segmenter->granularity());
52
53 // 4. Set segments.[[SegmentsString]] to string.
54 segments->set_unicode_string(*unicode_string);
55
56 // 5. Return segments.
57 return segments;
58 }
59
60 // ecma402 #sec-%segmentsprototype%.containing
Containing(Isolate * isolate,Handle<JSSegments> segments,double n_double)61 MaybeHandle<Object> JSSegments::Containing(Isolate* isolate,
62 Handle<JSSegments> segments,
63 double n_double) {
64 // 5. Let len be the length of string.
65 int32_t len = segments->unicode_string().raw()->length();
66
67 // 7. If n < 0 or n ≥ len, return undefined.
68 if (n_double < 0 || n_double >= len) {
69 return isolate->factory()->undefined_value();
70 }
71
72 int32_t n = static_cast<int32_t>(n_double);
73 // n may point to the surrogate tail- adjust it back to the lead.
74 n = segments->unicode_string().raw()->getChar32Start(n);
75
76 icu::BreakIterator* break_iterator = segments->icu_break_iterator().raw();
77 // 8. Let startIndex be ! FindBoundary(segmenter, string, n, before).
78 int32_t start_index =
79 break_iterator->isBoundary(n) ? n : break_iterator->preceding(n);
80
81 // 9. Let endIndex be ! FindBoundary(segmenter, string, n, after).
82 int32_t end_index = break_iterator->following(n);
83
84 // 10. Return ! CreateSegmentDataObject(segmenter, string, startIndex,
85 // endIndex).
86 return CreateSegmentDataObject(
87 isolate, segments->granularity(), break_iterator,
88 *(segments->unicode_string().raw()), start_index, end_index);
89 }
90
91 namespace {
92
CurrentSegmentIsWordLike(icu::BreakIterator * break_iterator)93 bool CurrentSegmentIsWordLike(icu::BreakIterator* break_iterator) {
94 int32_t rule_status = break_iterator->getRuleStatus();
95 return (rule_status >= UBRK_WORD_NUMBER &&
96 rule_status < UBRK_WORD_NUMBER_LIMIT) ||
97 (rule_status >= UBRK_WORD_LETTER &&
98 rule_status < UBRK_WORD_LETTER_LIMIT) ||
99 (rule_status >= UBRK_WORD_KANA &&
100 rule_status < UBRK_WORD_KANA_LIMIT) ||
101 (rule_status >= UBRK_WORD_IDEO && rule_status < UBRK_WORD_IDEO_LIMIT);
102 }
103
104 } // namespace
105
106 // ecma402 #sec-createsegmentdataobject
CreateSegmentDataObject(Isolate * isolate,JSSegmenter::Granularity granularity,icu::BreakIterator * break_iterator,const icu::UnicodeString & string,int32_t start_index,int32_t end_index)107 MaybeHandle<Object> JSSegments::CreateSegmentDataObject(
108 Isolate* isolate, JSSegmenter::Granularity granularity,
109 icu::BreakIterator* break_iterator, const icu::UnicodeString& string,
110 int32_t start_index, int32_t end_index) {
111 Factory* factory = isolate->factory();
112
113 // 1. Let len be the length of string.
114 // 2. Assert: startIndex ≥ 0.
115 DCHECK_GE(start_index, 0);
116 // 3. Assert: endIndex ≤ len.
117 DCHECK_LE(end_index, string.length());
118 // 4. Assert: startIndex < endIndex.
119 DCHECK_LT(start_index, end_index);
120
121 // 5. Let result be ! ObjectCreate(%ObjectPrototype%).
122 Handle<JSObject> result = factory->NewJSObject(isolate->object_function());
123
124 // 6. Let segment be the String value equal to the substring of string
125 // consisting of the code units at indices startIndex (inclusive) through
126 // endIndex (exclusive).
127 Handle<String> segment;
128 ASSIGN_RETURN_ON_EXCEPTION(
129 isolate, segment, Intl::ToString(isolate, string, start_index, end_index),
130 JSObject);
131
132 // 7. Perform ! CreateDataPropertyOrThrow(result, "segment", segment).
133 Maybe<bool> maybe_create_segment = JSReceiver::CreateDataProperty(
134 isolate, result, factory->segment_string(), segment, Just(kDontThrow));
135 DCHECK(maybe_create_segment.FromJust());
136 USE(maybe_create_segment);
137
138 // 8. Perform ! CreateDataPropertyOrThrow(result, "index", startIndex).
139 Maybe<bool> maybe_create_index = JSReceiver::CreateDataProperty(
140 isolate, result, factory->index_string(),
141 factory->NewNumberFromInt(start_index), Just(kDontThrow));
142 DCHECK(maybe_create_index.FromJust());
143 USE(maybe_create_index);
144
145 // 9. Perform ! CreateDataPropertyOrThrow(result, "input", string).
146 Handle<String> input_string;
147 ASSIGN_RETURN_ON_EXCEPTION(isolate, input_string,
148 Intl::ToString(isolate, string), JSObject);
149 Maybe<bool> maybe_create_input = JSReceiver::CreateDataProperty(
150 isolate, result, factory->input_string(), input_string, Just(kDontThrow));
151 DCHECK(maybe_create_input.FromJust());
152 USE(maybe_create_input);
153
154 Handle<Object> is_word_like;
155 // 10. Let granularity be segmenter.[[SegmenterGranularity]].
156 // 11. If granularity is "word", then
157 if (granularity == JSSegmenter::Granularity::WORD) {
158 // a. Let isWordLike be a Boolean value indicating whether the word segment
159 // segment in string is "word-like" according to locale
160 // segmenter.[[Locale]].
161 is_word_like = CurrentSegmentIsWordLike(break_iterator)
162 ? factory->true_value()
163 : factory->false_value();
164 // b. Perform ! CreateDataPropertyOrThrow(result, "isWordLike", isWordLike).
165 Maybe<bool> maybe_create_is_word_like = JSReceiver::CreateDataProperty(
166 isolate, result, factory->isWordLike_string(), is_word_like,
167 Just(kDontThrow));
168 DCHECK(maybe_create_is_word_like.FromJust());
169 USE(maybe_create_is_word_like);
170 }
171 return result;
172 }
173
GranularityAsString(Isolate * isolate) const174 Handle<String> JSSegments::GranularityAsString(Isolate* isolate) const {
175 return JSSegmenter::GetGranularityString(isolate, granularity());
176 }
177
178 } // namespace internal
179 } // namespace v8
180