Bug 1552098 - Add "Matched CSS Rules" command to the layout debugger. r=emilio

Differential Revision: https://phabricator.services.mozilla.com/D31397

--HG--
extra : moz-landing-system : lando

layout/generic/nsContainerFrame.cpp

@@ -2006,4 +2006,27 @@ void nsContainerFrame::List(FILE* out, const char* aPrefix,
     fprintf_stderr(out, "%s<>\n", str.get());
   }
 }
+
+void nsContainerFrame::ListWithMatchedRules(FILE* out,
+                                            const char* aPrefix) const {
+  fprintf_stderr(out, "%s%s\n", aPrefix, ListTag().get());
+
+  nsCString rulePrefix;
+  rulePrefix += aPrefix;
+  rulePrefix += "    ";
+  ListMatchedRules(out, rulePrefix.get());
+
+  nsCString childPrefix;
+  childPrefix += aPrefix;
+  childPrefix += "  ";
+
+  ChildListIterator lists(this);
+  for (; !lists.IsDone(); lists.Next()) {
+    nsFrameList::Enumerator childFrames(lists.CurrentList());
+    for (; !childFrames.AtEnd(); childFrames.Next()) {
+      nsIFrame* kid = childFrames.get();
+      kid->ListWithMatchedRules(out, childPrefix.get());
+    }
+  }
+}
 #endif

layout/generic/nsContainerFrame.h

@@ -73,6 +73,8 @@ class nsContainerFrame : public nsSplittableFrame {
 #ifdef DEBUG_FRAME_DUMP
   void List(FILE* out = stderr, const char* aPrefix = "",
             uint32_t aFlags = 0) const override;
+  void ListWithMatchedRules(FILE* out = stderr,
+                            const char* aPrefix = "") const override;
 #endif
 
   // nsContainerFrame methods

layout/generic/nsFrame.cpp

@@ -7605,6 +7605,26 @@ void nsIFrame::List(FILE* out, const char* aPrefix, uint32_t aFlags) const {
   fprintf_stderr(out, "%s\n", str.get());
 }
 
+void nsIFrame::ListMatchedRules(FILE* out, const char* aPrefix) const {
+  nsTArray<const RawServoStyleRule*> rawRuleList;
+  Servo_ComputedValues_GetStyleRuleList(mComputedStyle, &rawRuleList);
+  for (const RawServoStyleRule* rawRule : rawRuleList) {
+    nsString ruleText;
+    Servo_StyleRule_GetCssText(rawRule, &ruleText);
+    fprintf_stderr(out, "%s%s\n", aPrefix,
+                   NS_ConvertUTF16toUTF8(ruleText).get());
+  }
+}
+
+void nsIFrame::ListWithMatchedRules(FILE* out, const char* aPrefix) const {
+  fprintf_stderr(out, "%s%s\n", aPrefix, ListTag().get());
+
+  nsCString rulePrefix;
+  rulePrefix += aPrefix;
+  rulePrefix += "    ";
+  ListMatchedRules(out, rulePrefix.get());
+}
+
 nsresult nsFrame::GetFrameName(nsAString& aResult) const {
   return MakeFrameName(NS_LITERAL_STRING("Frame"), aResult);
 }

layout/generic/nsIFrame.h

@@ -4582,6 +4582,9 @@ class nsIFrame : public nsQueryFrame {
   enum {TRAVERSE_SUBDOCUMENT_FRAMES = 0x01};
   virtual void List(FILE* out = stderr, const char* aPrefix = "",
                     uint32_t aFlags = 0) const;
+  virtual void ListWithMatchedRules(FILE* out = stderr,
+                                    const char* aPrefix = "") const;
+  void ListMatchedRules(FILE* out, const char* aPrefix) const;
   /**
    * lists the frames beginning from the root frame
    * - calls root frame's List(...)

layout/tools/layout-debug/src/nsILayoutDebuggingTools.idl

@@ -46,6 +46,7 @@ interface nsILayoutDebuggingTools : nsISupports
     void dumpViews();
 
     void dumpStyleSheets();
+    void dumpMatchedRules();
     void dumpComputedStyles();
 
     void dumpReflowStats();

layout/tools/layout-debug/src/nsLayoutDebuggingTools.cpp

@@ -413,6 +413,22 @@ nsLayoutDebuggingTools::DumpStyleSheets() {
   return NS_OK;
 }
 
+NS_IMETHODIMP nsLayoutDebuggingTools::DumpMatchedRules() {
+  NS_ENSURE_TRUE(mDocShell, NS_ERROR_NOT_INITIALIZED);
+#ifdef DEBUG_FRAME_DUMP
+  FILE* out = stdout;
+  if (PresShell* presShell = GetPresShell(mDocShell)) {
+    nsIFrame* root = presShell->GetRootFrame();
+    if (root) {
+      root->ListWithMatchedRules(out);
+    }
+  } else {
+    fputs("null pres shell\n", out);
+  }
+#endif
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 nsLayoutDebuggingTools::DumpComputedStyles() {
   NS_ENSURE_TRUE(mDocShell, NS_ERROR_NOT_INITIALIZED);

layout/tools/layout-debug/ui/content/layoutdebug.xul

@@ -83,6 +83,7 @@
             <menuitem id="menu_dumpViews" label="&ldb.dumpViews.label;" accesskey="&ldb.dumpViews.accesskey;" oncommand="gDebugger.dumpViews();" />
             <menuseparator />
             <menuitem id="menu_dumpStyleSheets" label="&ldb.dumpStyleSheets.label;" accesskey="&ldb.dumpStyleSheets.accesskey;" oncommand="gDebugger.dumpStyleSheets();" />
+            <menuitem id="menu_dumpMatchedRules" label="&ldb.dumpMatchedRules.label;" accesskey="&ldb.dumpMatchedRules.accesskey;" oncommand="gDebugger.dumpMatchedRules();" />
             <menuitem id="menu_dumpComputedStyles" label="&ldb.dumpComputedStyles.label;" accesskey="&ldb.dumpComputedStyles.accesskey;" oncommand="gDebugger.dumpComputedStyles();" />
             <menuseparator />
             <menuitem id="menu_dumpReflowStats" label="&ldb.dumpReflowStats.label;" accesskey="&ldb.dumpReflowStats.accesskey;" oncommand="gDebugger.dumpReflowStats();" />

layout/tools/layout-debug/ui/locale/en-US/layoutdebug.dtd

@@ -70,6 +70,8 @@
 <!ENTITY ldb.dumpViews.accesskey "V">
 <!ENTITY ldb.dumpStyleSheets.label "Style Sheets">
 <!ENTITY ldb.dumpStyleSheets.accesskey "S">
+<!ENTITY ldb.dumpMatchedRules.label "Matched CSS Rules">
+<!ENTITY ldb.dumpMatchedRules.accesskey "M">
 <!ENTITY ldb.dumpComputedStyles.label "Style Contexts">
 <!ENTITY ldb.dumpComputedStyles.accesskey "x">
 <!ENTITY ldb.dumpReflowStats.label "Reflow Statistics">