Introduce NGPhysicalTextFragment::IsGeneratedText()

This patch introduces |NGPhysicalTextFragment::IsGeneratedText()| with
|NGTextType::kGeneratedText| to distinguish between normal text and generated
text, e.g. hyphen and ellipsis, for sorting fragments with |StartOffset()|.

This patch is a preparation of the patch[1].

[1] http://crrev.com/c/1114673 Make Element#innerText specification compliant

Bug: 859410
Cq-Include-Trybots: luci.chromium.try:linux_layout_tests_layout_ng
Change-Id: Ic9879985d1b5dd4cab921ce042ebc393043e3166
Reviewed-on: https://chromium-review.googlesource.com/1122061
Commit-Queue: Yoshifumi Inoue <yosin@chromium.org>
Reviewed-by: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#572478}

third_party/blink/renderer/core/layout/ng/inline/ng_physical_text_fragment.h

@@ -41,12 +41,18 @@ enum class NGLineOrientation {
 class CORE_EXPORT NGPhysicalTextFragment final : public NGPhysicalFragment {
  public:
   enum NGTextType {
+    // |text_| holds |NGNodeInlineData::text_content_|.
     kNormalText,
     kForcedLineBreak,
     // Flow controls are not to be painted. In particular, a tabulation
     // character and a soft-wrap opportunity.
     kFlowControl,
-    kSymbolMarker
+    kSymbolMarker,
+    // |text_| holds generated contents instead of |text_content_| in
+    // |NGNodeInlineData|, e.g. hyphen, and ellipsis.
+    // Note: Contents generated by CSS pseudo element, e.g. ::before, ::after,
+    // are not classified to this. See IsAnonymousText() for them.
+    kGeneratedText,
     // When adding new values, make sure the bit size of |sub_type_| is large
     // enough to store.
   };
@@ -78,6 +84,8 @@ class CORE_EXPORT NGPhysicalTextFragment final : public NGPhysicalFragment {
   }
 
   NGTextType TextType() const { return static_cast<NGTextType>(sub_type_); }
+  // True if this is a generated text.
+  bool IsGeneratedText() const { return TextType() == kGeneratedText; }
   // True if this is a forced line break.
   bool IsLineBreak() const { return TextType() == kForcedLineBreak; }
   // True if this is not for painting; i.e., a forced line break, a tabulation,

third_party/blink/renderer/core/layout/ng/inline/ng_physical_text_fragment_test.cc

@@ -35,6 +35,10 @@ class NGPhysicalTextFragmentTest : public NGLayoutTest {
     }
     return result;
   }
+
+  static std::string GetText(const NGPhysicalTextFragment& fragment) {
+    return fragment.Text().ToString().Utf8().data();
+  }
 };
 
 TEST_F(NGPhysicalTextFragmentTest, LocalRect) {
@@ -155,6 +159,32 @@ TEST_F(NGPhysicalTextFragmentTest, BeforeAndAfterAreAnonymousText) {
   EXPECT_TRUE(after.IsAnonymousText());
 }
 
+TEST_F(NGPhysicalTextFragmentTest, Ellipsis) {
+  LoadAhem();
+  SetBodyInnerHTML(R"HTML(
+      <style>
+      #sample {
+        font: 10px/1 Ahem;
+        overflow: hidden;
+        text-overflow: ellipsis;
+        width: 4ch;
+      }
+      </style>
+      <p id="sample">abcdef</p>
+  )HTML");
+  auto text_fragments = CollectTextFragmentsInContainer("sample");
+  ASSERT_EQ(2u, text_fragments.size());
+
+  const NGPhysicalTextFragment& abcdef = *text_fragments[0];
+  const NGPhysicalTextFragment& ellipsis = *text_fragments[1];
+  EXPECT_EQ(NGPhysicalTextFragment::kNormalText, abcdef.TextType());
+  EXPECT_FALSE(abcdef.IsGeneratedText());
+  EXPECT_EQ(u8"abc", GetText(abcdef));
+  EXPECT_EQ(NGPhysicalTextFragment::kGeneratedText, ellipsis.TextType());
+  EXPECT_TRUE(ellipsis.IsGeneratedText());
+  EXPECT_EQ(u8"\u2026", GetText(ellipsis));
+}
+
 TEST_F(NGPhysicalTextFragmentTest, ListMarkerIsAnonymousText) {
   SetBodyInnerHTML(
       "<ol style='list-style-position:inside'>"
@@ -170,6 +200,37 @@ TEST_F(NGPhysicalTextFragmentTest, ListMarkerIsAnonymousText) {
   EXPECT_FALSE(text.IsAnonymousText());
 }
 
+TEST_F(NGPhysicalTextFragmentTest, SoftHyphen) {
+  LoadAhem();
+  SetBodyInnerHTML(R"HTML(
+    <style>
+    #sample {
+      font: 10px/1 Ahem;
+      width: 3ch;
+    }
+    </style>
+    <p id="sample">abc&shy;def</p>
+  )HTML");
+  auto text_fragments = CollectTextFragmentsInContainer("sample");
+  ASSERT_EQ(3u, text_fragments.size());
+
+  const NGPhysicalTextFragment& abc = *text_fragments[0];
+  const NGPhysicalTextFragment& shy = *text_fragments[1];
+  const NGPhysicalTextFragment& def = *text_fragments[2];
+  EXPECT_EQ(NGPhysicalTextFragment::kNormalText, abc.TextType());
+  EXPECT_FALSE(abc.IsGeneratedText());
+  // Note: ShapeResult::RunInfo.width_ == 0 for U+00AD
+  EXPECT_EQ(u8"abc\u00AD", GetText(abc));
+  EXPECT_EQ(NGPhysicalTextFragment::kGeneratedText, shy.TextType());
+  EXPECT_TRUE(shy.IsGeneratedText());
+  // Note: |ComputedStyle::HypenString()| returns "-" or U+2010 based on
+  // glyph availability.
+  if (GetText(shy) != "-")
+    EXPECT_EQ(u8"\u2010", GetText(shy));
+  EXPECT_EQ(NGPhysicalTextFragment::kNormalText, def.TextType());
+  EXPECT_FALSE(def.IsGeneratedText());
+}
+
 TEST_F(NGPhysicalTextFragmentTest, QuotationMarksAreAnonymousText) {
   SetBodyInnerHTML("<div id=div><q>text</q></div>");
 

third_party/blink/renderer/core/layout/ng/inline/ng_text_fragment_builder.cc

@@ -40,6 +40,8 @@ void NGTextFragmentBuilder::SetItem(
     const NGInlineItemsData& items_data,
     NGInlineItemResult* item_result,
     LayoutUnit line_height) {
+  DCHECK_NE(text_type, NGPhysicalTextFragment::kGeneratedText)
+      << "Please use SetText() instead.";
   DCHECK(item_result);
   DCHECK(item_result->item->Style());
 
@@ -65,7 +67,7 @@ void NGTextFragmentBuilder::SetText(
   DCHECK(style);
   DCHECK(shape_result);
 
-  text_type_ = NGPhysicalTextFragment::kNormalText;
+  text_type_ = NGPhysicalTextFragment::kGeneratedText;
   text_ = text;
   item_index_ = std::numeric_limits<unsigned>::max();
   start_offset_ = shape_result->StartIndexForResult();

third_party/blink/renderer/core/layout/ng/inline/ng_text_fragment_builder.h

@@ -29,6 +29,8 @@ class CORE_EXPORT NGTextFragmentBuilder final : public NGBaseFragmentBuilder {
                const NGInlineItemsData&,
                NGInlineItemResult*,
                LayoutUnit line_height);
+
+  // Set text for generated text, e.g. hyphen and ellipsis.
   void SetText(LayoutObject*,
                const String& text,
                scoped_refptr<const ComputedStyle>,