fix wrap intrinsic height calculation (flutter#63420)

smadey · Aug 12, 2020 · 72619b8 · 72619b8
1 parent 41d41b3
commit 72619b8
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Showing 2 changed files with 52 additions and 2 deletions.
diff --git a/packages/flutter/lib/src/rendering/wrap.dart b/packages/flutter/lib/src/rendering/wrap.dart
@@ -409,7 +409,8 @@ class RenderWrap extends RenderBox
     int childCount = 0;
     RenderBox child = firstChild;
     while (child != null) {
-      final double childWidth = child.getMaxIntrinsicWidth(double.infinity);
+      // We want to make sure its width can only grow as big as the input width.
+      final double childWidth = math.min(child.getMaxIntrinsicWidth(double.infinity), width);
       final double childHeight = child.getMaxIntrinsicHeight(childWidth);
       // There must be at least one child before we move on to the next run.
       if (childCount > 0 && runWidth + childWidth + spacing > width) {
@@ -437,7 +438,8 @@ class RenderWrap extends RenderBox
     int childCount = 0;
     RenderBox child = firstChild;
     while (child != null) {
-      final double childHeight = child.getMaxIntrinsicHeight(double.infinity);
+      // We want to make sure its height can only grow as big as the input height.
+      final double childHeight = math.min(child.getMaxIntrinsicHeight(double.infinity), height);
       final double childWidth = child.getMaxIntrinsicWidth(childHeight);
       // There must be at least one child before we move on to the next run.
       if (childCount > 0 && runHeight + childHeight + spacing > height) {

diff --git a/packages/flutter/test/rendering/wrap_test.dart b/packages/flutter/test/rendering/wrap_test.dart
@@ -70,6 +70,54 @@ void main() {
     expect(renderWrap.computeMinIntrinsicHeight(79), 250);
   });
 
+  test('Compute intrinsic height test for width-in-height-out children', () {
+    const double lineHeight = 15.0;
+    final RenderWrap renderWrap = RenderWrap();
+    renderWrap.add(
+      RenderParagraph(
+        const TextSpan(
+          text: 'A very very very very very very very very long text',
+          style: TextStyle(fontSize: lineHeight),
+        ),
+        textDirection: TextDirection.ltr,
+      ),
+    );
+
+    renderWrap.spacing = 0;
+    renderWrap.runSpacing = 0;
+    renderWrap.direction = Axis.horizontal;
+
+    expect(renderWrap.computeMaxIntrinsicHeight(double.infinity), lineHeight);
+    expect(renderWrap.computeMaxIntrinsicHeight(600), 2 * lineHeight);
+    expect(renderWrap.computeMaxIntrinsicHeight(300), 3 * lineHeight);
+  });
+
+  test('Compute intrinsic width test for height-in-width-out children', () {
+    const double lineHeight = 15.0;
+    final RenderWrap renderWrap = RenderWrap();
+    renderWrap.add(
+      // Rotates a width-in-height-out render object to make it height-in-width-out.
+      RenderRotatedBox(
+        quarterTurns: 1,
+        child: RenderParagraph(
+          const TextSpan(
+            text: 'A very very very very very very very very long text',
+            style: TextStyle(fontSize: lineHeight),
+          ),
+          textDirection: TextDirection.ltr,
+        )
+      ),
+    );
+
+    renderWrap.spacing = 0;
+    renderWrap.runSpacing = 0;
+    renderWrap.direction = Axis.vertical;
+
+    expect(renderWrap.computeMaxIntrinsicWidth(double.infinity), lineHeight);
+    expect(renderWrap.computeMaxIntrinsicWidth(600), 2 * lineHeight);
+    expect(renderWrap.computeMaxIntrinsicWidth(300), 3 * lineHeight);
+  });
+
   test('Compute intrinsic width test', () {
     final List<RenderBox> children = <RenderBox>[
       RenderConstrainedBox(