From efab9b17ef04545e09dae3abdecea79f5dfd7cd5 Mon Sep 17 00:00:00 2001
From: Daniel Holbert <dholbert@cs.stanford.edu>
Date: Sat, 10 Mar 2012 14:49:10 -0800
Subject: [PATCH] Bug 640443: Allow positioned display:-moz-box elements to be
 containers for absolutely-positioned content. r=bz

---
 layout/base/nsCSSFrameConstructor.cpp         | 14 ++++++--
 .../box/flexbox-abspos-container-1-ref.html   | 27 +++++++++++++++
 .../box/flexbox-abspos-container-1a.html      | 30 +++++++++++++++++
 .../box/flexbox-abspos-container-1b.html      | 29 ++++++++++++++++
 .../box/flexbox-abspos-container-1c.html      | 33 +++++++++++++++++++
 .../box/flexbox-abspos-container-1d.html      | 31 +++++++++++++++++
 .../box/flexbox-abspos-container-2-ref.html   | 27 +++++++++++++++
 .../box/flexbox-abspos-container-2.html       | 31 +++++++++++++++++
 layout/reftests/box/reftest.list              |  5 +++
 layout/xul/base/src/nsBoxFrame.cpp            | 33 +++++++++++++++++++
 10 files changed, 258 insertions(+), 2 deletions(-)
 create mode 100644 layout/reftests/box/flexbox-abspos-container-1-ref.html
 create mode 100644 layout/reftests/box/flexbox-abspos-container-1a.html
 create mode 100644 layout/reftests/box/flexbox-abspos-container-1b.html
 create mode 100644 layout/reftests/box/flexbox-abspos-container-1c.html
 create mode 100644 layout/reftests/box/flexbox-abspos-container-1d.html
 create mode 100644 layout/reftests/box/flexbox-abspos-container-2-ref.html
 create mode 100644 layout/reftests/box/flexbox-abspos-container-2.html

diff --git a/layout/base/nsCSSFrameConstructor.cpp b/layout/base/nsCSSFrameConstructor.cpp
index e089329e1b40..6eedc39707e8 100644
--- a/layout/base/nsCSSFrameConstructor.cpp
+++ b/layout/base/nsCSSFrameConstructor.cpp
@@ -3914,6 +3914,12 @@ bool IsXULDisplayType(const nsStyleDisplay* aDisplay)
 #define SCROLLABLE_XUL_FCDATA(_func)                                    \
   FCDATA_DECL(FCDATA_DISALLOW_OUT_OF_FLOW | FCDATA_SKIP_ABSPOS_PUSH |   \
               FCDATA_MAY_NEED_SCROLLFRAME, _func)
+// .. but we allow some XUL frames to be _containers_ for out-of-flow content
+// (This is the same as SCROLLABLE_XUL_FCDATA, but w/o FCDATA_SKIP_ABSPOS_PUSH)
+#define SCROLLABLE_ABSPOS_CONTAINER_XUL_FCDATA(_func)                   \
+  FCDATA_DECL(FCDATA_DISALLOW_OUT_OF_FLOW |                             \
+              FCDATA_MAY_NEED_SCROLLFRAME, _func)
+
 #define SIMPLE_XUL_CREATE(_tag, _func)            \
   { &nsGkAtoms::_tag, SIMPLE_XUL_FCDATA(_func) }
 #define SCROLLABLE_XUL_CREATE(_tag, _func)            \
@@ -3922,6 +3928,8 @@ bool IsXULDisplayType(const nsStyleDisplay* aDisplay)
   { _int, SIMPLE_XUL_FCDATA(_func) }
 #define SCROLLABLE_XUL_INT_CREATE(_int, _func)                          \
   { _int, SCROLLABLE_XUL_FCDATA(_func) }
+#define SCROLLABLE_ABSPOS_CONTAINER_XUL_INT_CREATE(_int, _func)         \
+  { _int, SCROLLABLE_ABSPOS_CONTAINER_XUL_FCDATA(_func) }
 
 static
 nsIFrame* NS_NewGridBoxFrame(nsIPresShell* aPresShell,
@@ -4117,8 +4125,10 @@ nsCSSFrameConstructor::FindXULDisplayData(const nsStyleDisplay* aDisplay,
                                           nsStyleContext* aStyleContext)
 {
   static const FrameConstructionDataByInt sXULDisplayData[] = {
-    SCROLLABLE_XUL_INT_CREATE(NS_STYLE_DISPLAY_INLINE_BOX, NS_NewBoxFrame),
-    SCROLLABLE_XUL_INT_CREATE(NS_STYLE_DISPLAY_BOX, NS_NewBoxFrame),
+    SCROLLABLE_ABSPOS_CONTAINER_XUL_INT_CREATE(NS_STYLE_DISPLAY_INLINE_BOX,
+                                               NS_NewBoxFrame),
+    SCROLLABLE_ABSPOS_CONTAINER_XUL_INT_CREATE(NS_STYLE_DISPLAY_BOX,
+                                               NS_NewBoxFrame),
 #ifdef MOZ_XUL
     SCROLLABLE_XUL_INT_CREATE(NS_STYLE_DISPLAY_INLINE_GRID, NS_NewGridBoxFrame),
     SCROLLABLE_XUL_INT_CREATE(NS_STYLE_DISPLAY_GRID, NS_NewGridBoxFrame),
diff --git a/layout/reftests/box/flexbox-abspos-container-1-ref.html b/layout/reftests/box/flexbox-abspos-container-1-ref.html
new file mode 100644
index 000000000000..fbeaabf32aa5
--- /dev/null
+++ b/layout/reftests/box/flexbox-abspos-container-1-ref.html
@@ -0,0 +1,27 @@
+<!-- Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/ -->
+<html>
+  <head>
+    <style>
+      .relpos_parent {
+        position: relative;
+        width: 100px;
+        height: 100px;
+        background: lightblue;
+      }
+      .abspos_child {
+        position: absolute;
+        left: 30px;
+        bottom: 10px;
+        width: 20px;
+        height: 20px;
+        background: purple;
+      }
+    </style>
+  </head>
+  <body>
+    <div class="relpos_parent">
+      <div class="abspos_child"></div>
+    </div>
+  </body>
+</html>
diff --git a/layout/reftests/box/flexbox-abspos-container-1a.html b/layout/reftests/box/flexbox-abspos-container-1a.html
new file mode 100644
index 000000000000..1f6ee21a70d9
--- /dev/null
+++ b/layout/reftests/box/flexbox-abspos-container-1a.html
@@ -0,0 +1,30 @@
+<!-- Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/ -->
+<!-- This testcase has a relatively-positioned -moz-box element, which should
+     form a containing block for its absolutely positioned child. -->
+<html>
+  <head>
+    <style>
+      .box { display: -moz-box }
+      .relpos_parent {
+        position: relative;
+        width: 100px;
+        height: 100px;
+        background: lightblue;
+      }
+      .abspos_child {
+        position: absolute;
+        left: 30px;
+        bottom: 10px;
+        width: 20px;
+        height: 20px;
+        background: purple;
+      }
+    </style>
+  </head>
+  <body>
+    <div class="box relpos_parent">
+      <div class="abspos_child"></div>
+    </div>
+  </body>
+</html>
diff --git a/layout/reftests/box/flexbox-abspos-container-1b.html b/layout/reftests/box/flexbox-abspos-container-1b.html
new file mode 100644
index 000000000000..b19072382add
--- /dev/null
+++ b/layout/reftests/box/flexbox-abspos-container-1b.html
@@ -0,0 +1,29 @@
+<!-- Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/ -->
+<!-- This testcase is the same as the -1a version, but with -moz-inline-box. -->
+<html>
+  <head>
+    <style>
+      .box { display: -moz-inline-box }
+      .relpos_parent {
+        position: relative;
+        width: 100px;
+        height: 100px;
+        background: lightblue;
+      }
+      .abspos_child {
+        position: absolute;
+        left: 30px;
+        bottom: 10px;
+        width: 20px;
+        height: 20px;
+        background: purple;
+      }
+    </style>
+  </head>
+  <body>
+    <div class="box relpos_parent">
+      <div class="abspos_child"></div>
+    </div>
+  </body>
+</html>
diff --git a/layout/reftests/box/flexbox-abspos-container-1c.html b/layout/reftests/box/flexbox-abspos-container-1c.html
new file mode 100644
index 000000000000..553c9fc1b78c
--- /dev/null
+++ b/layout/reftests/box/flexbox-abspos-container-1c.html
@@ -0,0 +1,33 @@
+<!-- Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/ -->
+<!-- This testcase is the same as the -1a version, but with an additional
+     -moz-box wrapper, so that our relatively positioned box will never get a
+     call to Reflow. -->
+<html>
+  <head>
+    <style>
+      .box { display: -moz-box }
+      .relpos_parent {
+        position: relative;
+        width: 100px;
+        height: 100px;
+        background: lightblue;
+      }
+      .abspos_child {
+        position: absolute;
+        left: 30px;
+        bottom: 10px;
+        width: 20px;
+        height: 20px;
+        background: purple;
+      }
+    </style>
+  </head>
+  <body>
+    <div class="box">
+      <div class="box relpos_parent">
+        <div class="abspos_child"></div>
+      </div>
+    </div>
+  </body>
+</html>
diff --git a/layout/reftests/box/flexbox-abspos-container-1d.html b/layout/reftests/box/flexbox-abspos-container-1d.html
new file mode 100644
index 000000000000..78bb84fa75d7
--- /dev/null
+++ b/layout/reftests/box/flexbox-abspos-container-1d.html
@@ -0,0 +1,31 @@
+<!-- Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/ -->
+<!-- This testcase is the same as the -1c version, but with -moz-inline-box. -->
+<html>
+  <head>
+    <style>
+      .box { display: -moz-inline-box }
+      .relpos_parent {
+        position: relative;
+        width: 100px;
+        height: 100px;
+        background: lightblue;
+      }
+      .abspos_child {
+        position: absolute;
+        left: 30px;
+        bottom: 10px;
+        width: 20px;
+        height: 20px;
+        background: purple;
+      }
+    </style>
+  </head>
+  <body>
+    <div class="box">
+      <div class="box relpos_parent">
+        <div class="abspos_child"></div>
+      </div>
+    </div>
+  </body>
+</html>
diff --git a/layout/reftests/box/flexbox-abspos-container-2-ref.html b/layout/reftests/box/flexbox-abspos-container-2-ref.html
new file mode 100644
index 000000000000..d3ef61188765
--- /dev/null
+++ b/layout/reftests/box/flexbox-abspos-container-2-ref.html
@@ -0,0 +1,27 @@
+<!-- Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/ -->
+<html>
+  <head>
+    <style>
+      .relpos_parent {
+        position: relative;
+        width: 100px;
+        height: 100px;
+        background: lightblue;
+      }
+      .abspos_child {
+        position: absolute;
+        left: 30px;
+        top: 10px;
+        width: 20px;
+        height: 150px;
+        background: purple;
+      }
+    </style>
+  </head>
+  <body>
+    <div class="relpos_parent">
+      <div class="abspos_child"></div>
+    </div>
+  </body>
+</html>
diff --git a/layout/reftests/box/flexbox-abspos-container-2.html b/layout/reftests/box/flexbox-abspos-container-2.html
new file mode 100644
index 000000000000..aa3013f534e0
--- /dev/null
+++ b/layout/reftests/box/flexbox-abspos-container-2.html
@@ -0,0 +1,31 @@
+<!-- Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/ -->
+<!-- This testcase has a relatively-positioned -moz-box element, which should
+     form a containing block for its absolutely positioned child. Also: in
+     this case, the child is taller than its container. -->
+<html>
+  <head>
+    <style>
+      .box { display: -moz-box }
+      .relpos_parent {
+        position: relative;
+        width: 100px;
+        height: 100px;
+        background: lightblue;
+      }
+      .abspos_child {
+        position: absolute;
+        left: 30px;
+        top: 10px;
+        width: 20px;
+        height: 150px;
+        background: purple;
+      }
+    </style>
+  </head>
+  <body>
+    <div class="box relpos_parent">
+      <div class="abspos_child"></div>
+    </div>
+  </body>
+</html>
diff --git a/layout/reftests/box/reftest.list b/layout/reftests/box/reftest.list
index 7acadb49d0ea..e32a3e84d789 100644
--- a/layout/reftests/box/reftest.list
+++ b/layout/reftests/box/reftest.list
@@ -1,3 +1,8 @@
+== flexbox-abspos-container-1a.html flexbox-abspos-container-1-ref.html
+== flexbox-abspos-container-1b.html flexbox-abspos-container-1-ref.html
+== flexbox-abspos-container-1c.html flexbox-abspos-container-1-ref.html
+== flexbox-abspos-container-1d.html flexbox-abspos-container-1-ref.html
+== flexbox-abspos-container-2.html  flexbox-abspos-container-2-ref.html
 == flexbox-attributes-no-box-horizontal.xhtml flexbox-attributes-no-box-horizontal-ref.xhtml
 == flexbox-attributes-no-box-vertical.xhtml flexbox-attributes-no-box-vertical-ref.xhtml
 == flexbox-attributes-no-input-horizontal.xhtml flexbox-attributes-no-input-horizontal-ref.xhtml
diff --git a/layout/xul/base/src/nsBoxFrame.cpp b/layout/xul/base/src/nsBoxFrame.cpp
index 476a9cd08775..38db8793c26e 100644
--- a/layout/xul/base/src/nsBoxFrame.cpp
+++ b/layout/xul/base/src/nsBoxFrame.cpp
@@ -758,6 +758,8 @@ nsBoxFrame::Reflow(nsPresContext*          aPresContext,
   }
 #endif
 
+  ReflowAbsoluteFrames(aPresContext, aDesiredSize, aReflowState, aStatus);
+
   NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize);
   return NS_OK;
 }
@@ -934,6 +936,35 @@ nsBoxFrame::DoLayout(nsBoxLayoutState& aState)
 
   aState.SetLayoutFlags(oldFlags);
 
+  if (HasAbsolutelyPositionedChildren()) {
+    // Set up a |reflowState| to pass into ReflowAbsoluteFrames
+    nsHTMLReflowState reflowState(aState.PresContext(), this,
+                                  aState.GetRenderingContext(),
+                                  nsSize(mRect.width, NS_UNCONSTRAINEDSIZE));
+
+    // Set up a |desiredSize| to pass into ReflowAbsoluteFrames
+    nsHTMLReflowMetrics desiredSize;
+    desiredSize.width  = mRect.width;
+    desiredSize.height = mRect.height;
+
+    // get the ascent (cribbed from ::Reflow)
+    nscoord ascent = mRect.height;
+
+    // getting the ascent could be a lot of work. Don't get it if
+    // we are the root. The viewport doesn't care about it.
+    if (!(mState & NS_STATE_IS_ROOT)) {
+      ascent = GetBoxAscent(aState);
+    }
+    desiredSize.ascent = ascent;
+    desiredSize.mOverflowAreas = GetOverflowAreas();
+
+    // Set up a |reflowStatus| to pass into ReflowAbsoluteFrames
+    // (just a dummy value; hopefully that's OK)
+    nsReflowStatus reflowStatus = NS_FRAME_COMPLETE;
+    ReflowAbsoluteFrames(aState.PresContext(), desiredSize,
+                         reflowState, reflowStatus);
+  }
+
   return rv;
 }
 
@@ -946,6 +977,8 @@ nsBoxFrame::DestroyFrom(nsIFrame* aDestructRoot)
   // clean up the container box's layout manager and child boxes
   SetLayoutManager(nsnull);
 
+  DestroyAbsoluteFrames(aDestructRoot);
+
   nsContainerFrame::DestroyFrom(aDestructRoot);
 }