Fix adjustsFontSizeToFit for strings with a single character

facebook · Oct 17, 2024 · 3234b8e · 3234b8e
1 parent f673759
commit 3234b8e
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Showing 3 changed files with 20 additions and 5 deletions.
diff --git a/packages/react-native/Libraries/Text/Text/NSTextStorage+FontScaling.m b/packages/react-native/Libraries/Text/Text/NSTextStorage+FontScaling.m
@@ -66,6 +66,15 @@ - (RCTTextSizeComparisonOptions)compareToSize:(CGSize)size thresholdRatio:(CGFlo
   NSLayoutManager *layoutManager = self.layoutManagers.firstObject;
   NSTextContainer *textContainer = layoutManager.textContainers.firstObject;
 
+  // A workaround for truncatedGlyphRangeInLineFragmentForGlyphAtIndex returning NSNotFound when text has only
+  // one character and it gets truncated
+  if ([self length] == 1) {
+    CGSize characterSize = [[self string] sizeWithAttributes:[self attributesAtIndex:0 effectiveRange:nil]];
+    if (characterSize.width > size.width) {
+      return RCTTextSizeComparisonLarger;
+    }
+  }
+
   [layoutManager ensureLayoutForTextContainer:textContainer];
 
   // Does it fit the text container?

diff --git a/...-native/ReactAndroid/src/main/java/com/facebook/react/views/text/ReactTextShadowNode.java b/...-native/ReactAndroid/src/main/java/com/facebook/react/views/text/ReactTextShadowNode.java
@@ -75,6 +75,7 @@ public long measure(
                   "Spannable element has not been prepared in onBeforeLayout");
 
           Layout layout = measureSpannedText(text, width, widthMode);
+          TextPaint paint = new TextPaint(sTextPaintInstance);
 
           if (mAdjustsFontSizeToFit) {
             int initialFontSize = mTextAttributes.getEffectiveFontSize();
@@ -83,8 +84,9 @@ public long measure(
             int minimumFontSize =
                 (int) Math.max(mMinimumFontScale * initialFontSize, PixelUtil.toPixelFromDIP(4));
             while (currentFontSize > minimumFontSize
-                && (mNumberOfLines != ReactConstants.UNSET && layout.getLineCount() > mNumberOfLines
-                    || heightMode != YogaMeasureMode.UNDEFINED && layout.getHeight() > height)) {
+                && ((mNumberOfLines != ReactConstants.UNSET && layout.getLineCount() > mNumberOfLines
+                    || heightMode != YogaMeasureMode.UNDEFINED && layout.getHeight() > height)
+                  || (text.length() == 1 && paint.measureText(text.toString()) > width))) {
               // TODO: We could probably use a smarter algorithm here. This will require 0(n)
               // measurements
               // based on the number of points the font size needs to be reduced by.
@@ -94,13 +96,15 @@ public long measure(
               ReactAbsoluteSizeSpan[] sizeSpans =
                   text.getSpans(0, text.length(), ReactAbsoluteSizeSpan.class);
               for (ReactAbsoluteSizeSpan span : sizeSpans) {
+                int newSize = (int) Math.max((span.getSize() * ratio), minimumFontSize);
                 text.setSpan(
-                    new ReactAbsoluteSizeSpan(
-                        (int) Math.max((span.getSize() * ratio), minimumFontSize)),
+                    new ReactAbsoluteSizeSpan(newSize),
                     text.getSpanStart(span),
                     text.getSpanEnd(span),
                     text.getSpanFlags(span));
                 text.removeSpan(span);
+
+                paint.setTextSize(newSize);
               }
               layout = measureSpannedText(text, width, widthMode);
             }

diff --git a/...ct-native/ReactAndroid/src/main/java/com/facebook/react/views/text/TextLayoutManager.java b/...ct-native/ReactAndroid/src/main/java/com/facebook/react/views/text/TextLayoutManager.java
@@ -582,7 +582,8 @@ private static Layout createLayout(
                 && maximumNumberOfLines != 0
                 && layout.getLineCount() > maximumNumberOfLines)
             || (heightYogaMeasureMode != YogaMeasureMode.UNDEFINED
-                && layout.getHeight() > height))) {
+                && layout.getHeight() > height)
+            || (text.length() == 1 && layout.getPaint().measureText(text.toString()) > width))) {
       // TODO: We could probably use a smarter algorithm here. This will require 0(n)
       // measurements based on the number of points the font size needs to be reduced by.
       currentFontSize -= Math.max(1, (int) PixelUtil.toPixelFromDIP(1));
@@ -600,6 +601,7 @@ private static Layout createLayout(
             text.getSpanFlags(span));
         text.removeSpan(span);
       }
+      boring = BoringLayout.isBoring(text, paint);
       layout =
           createLayout(
               text,