Index: third_party/WebKit/Source/core/layout/ng/inline/ng_offset_mapping_builder.h |
diff --git a/third_party/WebKit/Source/core/layout/ng/inline/ng_offset_mapping_builder.h b/third_party/WebKit/Source/core/layout/ng/inline/ng_offset_mapping_builder.h |
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index 0000000000000000000000000000000000000000..03158f97d66e9974a1440e688896e35f0303c29b |
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+++ b/third_party/WebKit/Source/core/layout/ng/inline/ng_offset_mapping_builder.h |
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+// Copyright 2017 The Chromium Authors. All rights reserved. |
+// Use of this source code is governed by a BSD-style license that can be |
+// found in the LICENSE file. |
+ |
+#ifndef NGOffsetMappingBuilder_h |
+#define NGOffsetMappingBuilder_h |
+ |
+#include "core/CoreExport.h" |
+#include "platform/wtf/Allocator.h" |
+#include "platform/wtf/Vector.h" |
+#include "platform/wtf/text/WTFString.h" |
+ |
+namespace blink { |
+ |
+// This is the helper class for constructing the DOM-to-TextContent offset |
+// mapping. It holds an offset mapping, and provides APIs to modify the mapping |
+// step by step until the construction is finished. |
+// Design doc: https://goo.gl/CJbxky |
+// TODO(xiaochengh): Change the mock implemetation to a real one. |
+class CORE_EXPORT NGOffsetMappingBuilder { |
+ STACK_ALLOCATED(); |
+ |
+ public: |
+ NGOffsetMappingBuilder(); |
+ |
+ // TODO(xiaochengh): Add the following API when we implement the construction |
+ // of the concatenated offset mapping. |
+ // Associate the offset mapping with a simple annotation with the given node |
+ // as its value. |
+ // void Annotate(const Node&); |
+ |
+ // Append an identity offset mapping of the specified length with null |
+ // annotation to the builder. |
+ void AppendIdentityMapping(unsigned length); |
+ |
+ // Append a collapsed offset mapping from the specified length with null |
+ // annotation to the builder. |
+ void AppendCollapsedMapping(unsigned length); |
+ |
+ // TODO(xiaochengh): Add the following API when we start to fix offset mapping |
+ // for text-transform. |
+ // Append an expanded offset mapping to the specified length with null |
+ // annotation to the builder. |
+ // void AppendExpandedMapping(unsigned length); |
+ |
+ // This function should only be called by NGInlineItemsBuilder during |
+ // whitespace collapsing, and in the case that the target string of the |
+ // currently held mapping: |
+ // (i) has at least |skip_length + 1| characters, |
+ // (ii) has the last |skip_length| characters being non-text extra |
+ // characters, and |
+ // (iii) has the |skip_length + 1|-st last character being a space. |
+ // This function changes the space into collapsed. |
+ void CollapseTrailingSpace(unsigned index); |
+ |
+ // TODO(xiaochengh): Add the following API when we implement the construction |
+ // of the concatenated offset mapping. |
+ // Concatenate the offset mapping held by another builder to this builder. |
+ // void Concatenate(const OffsetMappingBuilder&); |
+ |
+ // TODO(xiaochengh): Add the following APIs when we implement the construction |
+ // of the DOM-to-TextContent offset mapping. |
+ |
+ // Composite the offset mapping held by another builder to this builder. |
+ // void Composite(const OffsetMappingBuilder&); |
+ |
+ // Finalize and return the offset mapping. |
+ // OffsetMappingResult Build(); |
+ |
+ // Exposed for testing only. |
+ Vector<unsigned> DumpOffsetMappingForTesting() const; |
+ |
+ private: |
+ // A mock implementation of the offset mapping builder that stores the mapping |
+ // value of every offset in the plain way. This is simple but inefficient, and |
+ // will be replaced by a real efficient implementation. |
+ Vector<unsigned> mapping_; |
+ |
+ DISALLOW_COPY_AND_ASSIGN(NGOffsetMappingBuilder); |
+}; |
+ |
+} // namespace blink |
+ |
+#endif // OffsetMappingBuilder_h |