From 025be8148a9abc533a8ae108e49cfd3f4512c581 Mon Sep 17 00:00:00 2001
From: Tim Yung <yungsters@fb.com>
Date: Thu, 23 Apr 2020 19:09:12 -0700
Subject: [PATCH] RN: Fix Text Layout Ignoring Parent Bounds

Summary:
Fixes text layout so that the parent bounds are correctly respected. This fixes two bugs:

- **Parent width is not respected.** This was caused by the recent change to shrink-wrap text layout.
- **Parent height is not respected.** This has always been a bug.

After this change, Android will behave like iOS.

Changelog:
[Android] [Fixed] - Text layout no longer ignores parent bounds

Reviewed By: mdvacca

Differential Revision: D21199030

fbshipit-source-id: cc072bdcff64167db1f79b7bf965e57a7396cdf4
---
 .../react/views/text/ReactTextShadowNode.java | 25 ++++++++++++---
 .../react/views/text/TextLayoutManager.java   | 31 ++++++++++++++-----
 2 files changed, 43 insertions(+), 13 deletions(-)

diff --git a/ReactAndroid/src/main/java/com/facebook/react/views/text/ReactTextShadowNode.java b/ReactAndroid/src/main/java/com/facebook/react/views/text/ReactTextShadowNode.java
index b9fc8e75a255c4..ac84caae1e07d9 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/views/text/ReactTextShadowNode.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/views/text/ReactTextShadowNode.java
@@ -130,14 +130,29 @@ public long measure(
           // Instead of using `layout.getWidth()` (which may yield a significantly larger width for
           // text that is wrapping), compute width using the longest line.
           float layoutWidth = 0;
-          for (int lineIndex = 0; lineIndex < lineCount; lineIndex++) {
-            float lineWidth = layout.getLineWidth(lineIndex);
-            if (lineWidth > layoutWidth) {
-              layoutWidth = lineWidth;
+          if (widthMode == YogaMeasureMode.EXACTLY) {
+            layoutWidth = width;
+          } else {
+            for (int lineIndex = 0; lineIndex < lineCount; lineIndex++) {
+              float lineWidth = layout.getLineWidth(lineIndex);
+              if (lineWidth > layoutWidth) {
+                layoutWidth = lineWidth;
+              }
+            }
+            if (widthMode == YogaMeasureMode.AT_MOST && layoutWidth > width) {
+              layoutWidth = width;
+            }
+          }
+
+          float layoutHeight = height;
+          if (heightMode != YogaMeasureMode.EXACTLY) {
+            layoutHeight = layout.getLineBottom(lineCount - 1);
+            if (heightMode == YogaMeasureMode.AT_MOST && layoutHeight > height) {
+              layoutHeight = height;
             }
           }
 
-          return YogaMeasureOutput.make(layoutWidth, layout.getLineBottom(lineCount - 1));
+          return YogaMeasureOutput.make(layoutWidth, layoutHeight);
         }
       };
 
diff --git a/ReactAndroid/src/main/java/com/facebook/react/views/text/TextLayoutManager.java b/ReactAndroid/src/main/java/com/facebook/react/views/text/TextLayoutManager.java
index 2213ec612823e0..bf5849bbe4a94f 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/views/text/TextLayoutManager.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/views/text/TextLayoutManager.java
@@ -311,14 +311,28 @@ public static long measureText(
             ? layout.getLineCount()
             : Math.min(maximumNumberOfLines, layout.getLineCount());
 
-    int calculatedHeight = layout.getLineBottom(calculatedLineCount - 1);
     // Instead of using `layout.getWidth()` (which may yield a significantly larger width for
     // text that is wrapping), compute width using the longest line.
-    int calculatedWidth = 0;
-    for (int lineIndex = 0; lineIndex < calculatedLineCount; lineIndex++) {
-      float lineWidth = layout.getLineWidth(lineIndex);
-      if (lineWidth > calculatedWidth) {
-        calculatedWidth = (int) Math.ceil(lineWidth);
+    float calculatedWidth = 0;
+    if (widthYogaMeasureMode == YogaMeasureMode.EXACTLY) {
+      calculatedWidth = width;
+    } else {
+      for (int lineIndex = 0; lineIndex < calculatedLineCount; lineIndex++) {
+        float lineWidth = layout.getLineWidth(lineIndex);
+        if (lineWidth > calculatedWidth) {
+          calculatedWidth = lineWidth;
+        }
+      }
+      if (widthYogaMeasureMode == YogaMeasureMode.AT_MOST && calculatedWidth > width) {
+        calculatedWidth = width;
+      }
+    }
+
+    float calculatedHeight = height;
+    if (heightYogaMeasureMode != YogaMeasureMode.EXACTLY) {
+      calculatedHeight = layout.getLineBottom(calculatedLineCount - 1);
+      if (heightYogaMeasureMode == YogaMeasureMode.AT_MOST && calculatedHeight > height) {
+        calculatedHeight = height;
       }
     }
 
@@ -356,7 +370,7 @@ public static long measureText(
                 isRtlParagraph
                     // Equivalent to `layout.getLineLeft(line)` but `getLineLeft` returns incorrect
                     // values when the paragraph is RTL and `setSingleLine(true)`.
-                    ? calculatedWidth - (int) layout.getLineWidth(line)
+                    ? (int) calculatedWidth - (int) layout.getLineWidth(line)
                     : (int) layout.getLineRight(line) - placeholderWidth;
           } else {
             // The direction of the paragraph may not be exactly the direction the string is heading
@@ -379,7 +393,8 @@ public static long measureText(
               // The result is equivalent to bugless versions of
               // `getPrimaryHorizontal`/`getSecondaryHorizontal`.
               placeholderLeftPosition =
-                  calculatedWidth - ((int) layout.getLineRight(line) - placeholderLeftPosition);
+                  (int) calculatedWidth
+                      - ((int) layout.getLineRight(line) - placeholderLeftPosition);
             }
             if (isRtlChar) {
               placeholderLeftPosition -= placeholderWidth;