Add fixYogaFlexBasisFitContentInMainAxis flag to avoid unnecessary re-measurement

enums.py

@@ -76,6 +76,9 @@
         # Absolute nodes will resolve percentages against the inner size of
         # their containing node, not the padding box
         ("AbsolutePercentAgainstInnerSize", 1 << 2),
+        # Applies a FitContent constraint in the main axis during flex basis
+        # computation for non-measure container nodes
+        ("FlexBasisFitContentInMainAxis", 1 << 3),
         # Enable all incorrect behavior (preserve compatibility)
         ("All", 0x7FFFFFFF),
         # Enable all errata except for "StretchFlexBasis" (Defaults behavior

gentest/fixtures/YGFlexBasisFitContentInMainAxisTest.html

@@ -0,0 +1,68 @@
+<!-- Container child with content overflowing definite column parent.
+     Without FlexBasisFitContentInMainAxis errata (corrected behavior),
+     flex basis uses MaxContent: child height = content height (500),
+     not capped by parent's available height. -->
+<div id="container_child_overflows_definite_parent_column"
+     style="width: 200px; height: 300px;">
+  <div>
+    <div style="height: 500px; width: 50px;"></div>
+  </div>
+</div>
+
+<!-- Row variant: container child overflows definite row parent. -->
+<div id="container_child_overflows_definite_parent_row"
+     style="width: 300px; height: 200px; flex-direction: row;">
+  <div>
+    <div style="width: 500px; height: 50px;"></div>
+  </div>
+</div>
+
+<!-- Container child content fits within parent bounds.
+     Same behavior with and without errata (no capping needed). -->
+<div id="container_child_within_bounds_column"
+     style="width: 200px; height: 300px;">
+  <div>
+    <div style="height: 100px; width: 50px;"></div>
+  </div>
+</div>
+
+<!-- Multiple container children, both overflowing definite column parent. -->
+<div id="multiple_container_children_overflow_column"
+     style="width: 200px; height: 300px;">
+  <div>
+    <div style="height: 400px;"></div>
+  </div>
+  <div>
+    <div style="height: 500px;"></div>
+  </div>
+</div>
+
+<!-- Scroll container: children always use MaxContent in main axis.
+     Same behavior with and without errata. -->
+<div id="scroll_container_column"
+     style="width: 200px; height: 300px; overflow: scroll;">
+  <div>
+    <div style="height: 500px;"></div>
+  </div>
+</div>
+
+<!-- Mix of explicit-height child and overflowing container child. -->
+<div id="explicit_and_container_children_column"
+     style="width: 200px; height: 300px;">
+  <div style="height: 100px;"></div>
+  <div>
+    <div style="height: 500px;"></div>
+  </div>
+</div>
+
+<!-- Items with flex-basis inside a scroll container's auto-height
+     content container. Without errata, flex-basis is respected even
+     when the content container's main axis size is indefinite (NaN).
+     With errata, flex-basis would be ignored. -->
+<div id="flex_basis_in_scroll_content_container"
+     style="width: 200px; height: 300px; overflow: scroll;">
+  <div>
+    <div style="flex-basis: 200px;"></div>
+    <div style="flex-basis: 300px;"></div>
+  </div>
+</div>

java/com/facebook/yoga/YogaErrata.java

@@ -14,6 +14,7 @@ public enum YogaErrata {
   STRETCH_FLEX_BASIS(1),
   ABSOLUTE_POSITION_WITHOUT_INSETS_EXCLUDES_PADDING(2),
   ABSOLUTE_PERCENT_AGAINST_INNER_SIZE(4),
+  FLEX_BASIS_FIT_CONTENT_IN_MAIN_AXIS(8),
   ALL(2147483647),
   CLASSIC(2147483646);
 
@@ -33,6 +34,7 @@ public static YogaErrata fromInt(int value) {
       case 1: return STRETCH_FLEX_BASIS;
       case 2: return ABSOLUTE_POSITION_WITHOUT_INSETS_EXCLUDES_PADDING;
       case 4: return ABSOLUTE_PERCENT_AGAINST_INNER_SIZE;
+      case 8: return FLEX_BASIS_FIT_CONTENT_IN_MAIN_AXIS;
       case 2147483647: return ALL;
       case 2147483646: return CLASSIC;
       default: throw new IllegalArgumentException("Unknown enum value: " + value);