Newline character support and truncated line sizing improvement.

CHANGELOG.md

@@ -1,5 +1,6 @@
 ## master
 * Add your own contributions to the next release on the line below this with your name.
+- [ASTextNode2] Newline character support and truncated line sizing improvement.  [Kevin Smith](https://github.com/wiseoldduck). [#1193](https://github.com/TextureGroup/Texture/pull/1193)
 - [ASScrollNode] A11y support for ASScrollNode. [Max Wang](https://github.com/wsdwsd0829). [#1188](https://github.com/TextureGroup/Texture/pull/1188)
 - [ASDisplayNode.m] Make sure node is loaded before enter visible. [Max Wang](https://github.com/wsdwsd0829). [#886](https://github.com/TextureGroup/Texture/pull/886)
 - [ASTextNode2] Add improved support for all line-break modes in experimental text node. [Kevin Smith](https://github.com/wiseoldduck). [#1150](https://github.com/TextureGroup/Texture/pull/1150)

Source/ASTextNode2.mm

@@ -350,7 +350,10 @@ - (CGSize)calculateSizeThatFits:(CGSize)constrainedSize
   NSMutableAttributedString *mutableText = [_attributedText mutableCopy];
   [self prepareAttributedString:mutableText isForIntrinsicSize:isCalculatingIntrinsicSize];
   ASTextLayout *layout = ASTextNodeCompatibleLayoutWithContainerAndText(_textContainer, mutableText);
-
+  if (layout.truncatedLine != nil && layout.truncatedLine.size.width > layout.textBoundingSize.width) {
+    return (CGSize) {MIN(constrainedSize.width, layout.truncatedLine.size.width), layout.textBoundingSize.height};
+  }
+
   return layout.textBoundingSize;
 }
 

Source/Private/TextExperiment/Component/ASTextLayout.m

@@ -441,7 +441,7 @@ + (ASTextLayout *)layoutWithContainer:(ASTextContainer *)container text:(NSAttri
   // It may use larger constraint size when create CTFrame with
   // CTFramesetterCreateFrame in iOS 10.
   BOOL needFixLayoutSizeBug = AS_AT_LEAST_IOS10;
-  
+
   layout = [[ASTextLayout alloc] _init];
   layout.text = text;
   layout.container = container;
@@ -834,23 +834,33 @@ + (ASTextLayout *)layoutWithContainer:(ASTextContainer *)container text:(NSAttri
             }
           }
           int i = 0;
-          if (type != kCTLineTruncationStart) { // Middle or End/Tail wants text preceding truncated content
+          if (type != kCTLineTruncationStart) { // Middle or End/Tail wants text preceding truncated content.
             i = removedLines.count - 1;
             while (atLeastOneLine < truncatedWidth && i >= 0) {
+              if (lastLineText.length > 0 && [lastLineText.string characterAtIndex:lastLineText.string.length - 1] == '\n') { // Explicit newlines are always "long enough".
+                [lastLineText deleteCharactersInRange:NSMakeRange(lastLineText.string.length - 1, 1)];
+                break;
+              }
               [lastLineText appendAttributedString:[text attributedSubstringFromRange:removedLines[i].range]];
               atLeastOneLine += removedLines[i--].width;
             }
             [lastLineText appendAttributedString:truncationToken];
           }
-          if (type != kCTLineTruncationEnd && removedLines.count > 0) { // Middle or Start/Head wants text following truncated content
+          if (type != kCTLineTruncationEnd && removedLines.count > 0) { // Middle or Start/Head wants text following truncated content.
             i = 0;
             atLeastOneLine = removedLines[i].width;
             while (atLeastOneLine < truncatedWidth && i < removedLines.count) {
               atLeastOneLine += removedLines[i++].width;
             }
             for (i--; i >= 0; i--) {
-              [lastLineText appendAttributedString:[text attributedSubstringFromRange:removedLines[i].range]];
+              NSAttributedString *nextLine = [text attributedSubstringFromRange:removedLines[i].range];
+              if ([nextLine.string characterAtIndex:nextLine.string.length - 1] == '\n') { // Explicit newlines are always "long enough".
+                lastLineText = [NSMutableAttributedString new];
+              } else {
+                [lastLineText appendAttributedString:nextLine];
+              }
             }
+            [lastLineText insertAttributedString:truncationToken atIndex:0];
           }
 
           CTLineRef ctLastLineExtend = CTLineCreateWithAttributedString((CFAttributedStringRef) lastLineText);