tor-browser

commit 54d25f5169e652ac6fa46fe988b5749a1c60d8f0
parent 9cc829db5defd8fae72591734116023bbd6021de
Author: Jonathan Watt <jwatt@jwatt.org>
Date:   Tue,  9 Dec 2025 20:34:24 +0000

Bug 1991929 p2. Move MapCSSAlignment() to CSSAlignUtils. r=emilio,layout-reviewers,layout-anchor-positioning-reviewers

Differential Revision: https://phabricator.services.mozilla.com/D275082

Diffstat:
M
layout/generic/CSSAlignUtils.cpp
 | 
41
+++++++++++++++++++++++++++++++++++++++++
M
layout/generic/CSSAlignUtils.h
 | 
8
++++++++
M
layout/generic/nsContainerFrame.cpp
 | 
46
+++++-----------------------------------------

3 files changed, 54 insertions(+), 41 deletions(-)
diff --git a/layout/generic/CSSAlignUtils.cpp b/layout/generic/CSSAlignUtils.cpp
@@ -9,9 +9,50 @@
 #include "CSSAlignUtils.h"
 
 #include "ReflowInput.h"
+#include "nsIFrame.h"
 
 namespace mozilla {
 
+StyleAlignFlags CSSAlignUtils::UsedAlignmentForAbsPos(nsIFrame* aFrame,
+                                                      StyleAlignFlags aFlags,
+                                                      LogicalAxis aLogicalAxis,
+                                                      WritingMode aCBWM) {
+  MOZ_ASSERT(aFrame->IsAbsolutelyPositioned());
+
+  // Extract and strip the flag bits
+  StyleAlignFlags alignmentFlags = aFlags & StyleAlignFlags::FLAG_BITS;
+  aFlags &= ~StyleAlignFlags::FLAG_BITS;
+
+  if (aFlags == StyleAlignFlags::NORMAL) {
+    // "the 'normal' keyword behaves as 'start' on replaced
+    // absolutely-positioned boxes, and behaves as 'stretch' on all other
+    // absolutely-positioned boxes."
+    // https://drafts.csswg.org/css-align/#align-abspos
+    // https://drafts.csswg.org/css-align/#justify-abspos
+    aFlags = aFrame->IsReplaced() ? StyleAlignFlags::START
+                                  : StyleAlignFlags::STRETCH;
+  } else if (aFlags == StyleAlignFlags::FLEX_START) {
+    aFlags = StyleAlignFlags::START;
+  } else if (aFlags == StyleAlignFlags::FLEX_END) {
+    aFlags = StyleAlignFlags::END;
+  } else if (aFlags == StyleAlignFlags::LEFT ||
+             aFlags == StyleAlignFlags::RIGHT) {
+    if (aLogicalAxis == LogicalAxis::Inline) {
+      const bool isLeft = (aFlags == StyleAlignFlags::LEFT);
+      aFlags = (isLeft == aCBWM.IsBidiLTR()) ? StyleAlignFlags::START
+                                             : StyleAlignFlags::END;
+    } else {
+      aFlags = StyleAlignFlags::START;
+    }
+  } else if (aFlags == StyleAlignFlags::BASELINE) {
+    aFlags = StyleAlignFlags::START;
+  } else if (aFlags == StyleAlignFlags::LAST_BASELINE) {
+    aFlags = StyleAlignFlags::END;
+  }
+
+  return (aFlags | alignmentFlags);
+}
+
 static nscoord SpaceToFill(WritingMode aWM, const LogicalSize& aSize,
                            nscoord aMargin, LogicalAxis aAxis,
                            nscoord aCBSize) {
diff --git a/layout/generic/CSSAlignUtils.h b/layout/generic/CSSAlignUtils.h
@@ -20,6 +20,14 @@ struct StyleAlignFlags;
 class CSSAlignUtils {
  public:
   /**
+   * Map a raw StyleAlignFlags value to the used one.
+   */
+  static StyleAlignFlags UsedAlignmentForAbsPos(nsIFrame* aFrame,
+                                                StyleAlignFlags aFlags,
+                                                LogicalAxis aLogicalAxis,
+                                                WritingMode aCBWM);
+
+  /**
    * Flags to customize the behavior of AlignJustifySelf:
    */
   enum class AlignJustifyFlag {
diff --git a/layout/generic/nsContainerFrame.cpp b/layout/generic/nsContainerFrame.cpp
@@ -11,6 +11,7 @@
 #include <algorithm>
 
 #include "AnchorPositioningUtils.h"
+#include "CSSAlignUtils.h"
 #include "mozilla/AbsoluteContainingBlock.h"
 #include "mozilla/AutoRestore.h"
 #include "mozilla/ComputedStyle.h"
@@ -2457,45 +2458,6 @@ void nsContainerFrame::ConsiderChildOverflow(OverflowAreas& aOverflowAreas,
   }
 }
 
-// Map a raw StyleAlignFlags value to the used one.
-static StyleAlignFlags MapCSSAlignment(StyleAlignFlags aFlags,
-                                       const ReflowInput& aChildRI,
-                                       LogicalAxis aLogicalAxis,
-                                       WritingMode aWM) {
-  // Extract and strip the flag bits
-  StyleAlignFlags alignmentFlags = aFlags & StyleAlignFlags::FLAG_BITS;
-  aFlags &= ~StyleAlignFlags::FLAG_BITS;
-
-  if (aFlags == StyleAlignFlags::NORMAL) {
-    // "the 'normal' keyword behaves as 'start' on replaced
-    // absolutely-positioned boxes, and behaves as 'stretch' on all other
-    // absolutely-positioned boxes."
-    // https://drafts.csswg.org/css-align/#align-abspos
-    // https://drafts.csswg.org/css-align/#justify-abspos
-    aFlags = aChildRI.mFrame->IsReplaced() ? StyleAlignFlags::START
-                                           : StyleAlignFlags::STRETCH;
-  } else if (aFlags == StyleAlignFlags::FLEX_START) {
-    aFlags = StyleAlignFlags::START;
-  } else if (aFlags == StyleAlignFlags::FLEX_END) {
-    aFlags = StyleAlignFlags::END;
-  } else if (aFlags == StyleAlignFlags::LEFT ||
-             aFlags == StyleAlignFlags::RIGHT) {
-    if (aLogicalAxis == LogicalAxis::Inline) {
-      const bool isLeft = (aFlags == StyleAlignFlags::LEFT);
-      aFlags = (isLeft == aWM.IsBidiLTR()) ? StyleAlignFlags::START
-                                           : StyleAlignFlags::END;
-    } else {
-      aFlags = StyleAlignFlags::START;
-    }
-  } else if (aFlags == StyleAlignFlags::BASELINE) {
-    aFlags = StyleAlignFlags::START;
-  } else if (aFlags == StyleAlignFlags::LAST_BASELINE) {
-    aFlags = StyleAlignFlags::END;
-  }
-
-  return (aFlags | alignmentFlags);
-}
-
 StyleAlignFlags nsContainerFrame::CSSAlignmentForAbsPosChild(
     const ReflowInput& aChildRI, LogicalAxis aLogicalAxis) const {
   MOZ_ASSERT(aChildRI.mFrame->IsAbsolutelyPositioned(),
@@ -2504,7 +2466,8 @@ StyleAlignFlags nsContainerFrame::CSSAlignmentForAbsPosChild(
   // `auto` takes from parent's `align-items`.
   StyleAlignFlags alignment =
       aChildRI.mStylePosition->UsedSelfAlignment(aLogicalAxis, Style());
-  return MapCSSAlignment(alignment, aChildRI, aLogicalAxis, GetWritingMode());
+  return CSSAlignUtils::UsedAlignmentForAbsPos(aChildRI.mFrame, alignment,
+                                               aLogicalAxis, GetWritingMode());
 }
 
 StyleAlignFlags
@@ -2561,7 +2524,8 @@ nsContainerFrame::CSSAlignmentForAbsPosChildWithinContainingBlock(
     }
   }
 
-  return MapCSSAlignment(alignment, aChildRI, aLogicalAxis, GetWritingMode());
+  return CSSAlignUtils::UsedAlignmentForAbsPos(aChildRI.mFrame, alignment,
+                                               aLogicalAxis, GetWritingMode());
 }
 
 nsOverflowContinuationTracker::nsOverflowContinuationTracker(