From 131556a889dba259618f631e56cc9aec737abbdf Mon Sep 17 00:00:00 2001
From: Tom Tromey <tromey@mozilla.com>
Date: Mon, 17 Aug 2015 15:19:21 -0700
Subject: [PATCH] Bug 1013814 - add inIDOMUtils.getRelativeRuleLine;
 r=heycam,pbrosset

---
 dom/base/nsIStyleSheetLinkingElement.h        | 12 +++-
 dom/base/nsStyleLinkElement.cpp               |  6 ++
 dom/base/nsStyleLinkElement.h                 |  1 +
 layout/inspector/inDOMUtils.cpp               | 28 ++++++++
 layout/inspector/inIDOMUtils.idl              | 12 +++-
 layout/inspector/tests/mochitest.ini          |  1 +
 .../tests/test_getRelativeRuleLine.html       | 67 +++++++++++++++++++
 toolkit/devtools/server/actors/csscoverage.js |  5 +-
 toolkit/devtools/server/actors/stylesheets.js | 47 -------------
 9 files changed, 127 insertions(+), 52 deletions(-)
 create mode 100644 layout/inspector/tests/test_getRelativeRuleLine.html

diff --git a/dom/base/nsIStyleSheetLinkingElement.h b/dom/base/nsIStyleSheetLinkingElement.h
index 948cdf9c4524..77eaebf6096f 100644
--- a/dom/base/nsIStyleSheetLinkingElement.h
+++ b/dom/base/nsIStyleSheetLinkingElement.h
@@ -13,8 +13,8 @@ class nsICSSLoaderObserver;
 class nsIURI;
 
 #define NS_ISTYLESHEETLINKINGELEMENT_IID          \
-{ 0xe5855604, 0x8a9a, 0x4181, \
- { 0xbe, 0x41, 0xdd, 0xf7, 0x08, 0x70, 0x3f, 0xbe } }
+{ 0xa8b79f3b, 0x9d18, 0x4f9c, \
+  { 0xb1, 0xaa, 0x8c, 0x9b, 0x1b, 0xaa, 0xac, 0xad } }
 
 namespace mozilla {
 class CSSStyleSheet;
@@ -97,6 +97,14 @@ public:
   // some types of linking elements, but it's a better place than
   // anywhere else.
   virtual void SetLineNumber(uint32_t aLineNumber) = 0;
+
+  /**
+   * Get the line number, as previously set by SetLineNumber.
+   *
+   * @return the line number of this element; or 1 if no line number
+   *         was set
+   */
+  virtual uint32_t GetLineNumber() = 0;
 };
 
 NS_DEFINE_STATIC_IID_ACCESSOR(nsIStyleSheetLinkingElement,
diff --git a/dom/base/nsStyleLinkElement.cpp b/dom/base/nsStyleLinkElement.cpp
index 11164c5d86f7..c7a175c021d2 100644
--- a/dom/base/nsStyleLinkElement.cpp
+++ b/dom/base/nsStyleLinkElement.cpp
@@ -119,6 +119,12 @@ nsStyleLinkElement::SetLineNumber(uint32_t aLineNumber)
   mLineNumber = aLineNumber;
 }
 
+/* virtual */ uint32_t
+nsStyleLinkElement::GetLineNumber()
+{
+  return mLineNumber;
+}
+
 /* static */ bool
 nsStyleLinkElement::IsImportEnabled()
 {
diff --git a/dom/base/nsStyleLinkElement.h b/dom/base/nsStyleLinkElement.h
index 9cd5f71d9022..1d7dd5d3744b 100644
--- a/dom/base/nsStyleLinkElement.h
+++ b/dom/base/nsStyleLinkElement.h
@@ -52,6 +52,7 @@ public:
 
   virtual void OverrideBaseURI(nsIURI* aNewBaseURI) override;
   virtual void SetLineNumber(uint32_t aLineNumber) override;
+  virtual uint32_t GetLineNumber() override;
 
   enum RelValue {
     ePREFETCH =     0x00000001,
diff --git a/layout/inspector/inDOMUtils.cpp b/layout/inspector/inDOMUtils.cpp
index 9989be817f3d..f2ff3247f74c 100644
--- a/layout/inspector/inDOMUtils.cpp
+++ b/layout/inspector/inDOMUtils.cpp
@@ -12,6 +12,7 @@
 #include "nsIServiceManager.h"
 #include "nsISupportsArray.h"
 #include "nsString.h"
+#include "nsIStyleSheetLinkingElement.h"
 #include "nsIDOMElement.h"
 #include "nsIDocument.h"
 #include "nsIPresShell.h"
@@ -290,6 +291,33 @@ inDOMUtils::GetRuleColumn(nsIDOMCSSRule* aRule, uint32_t* _retval)
   return NS_OK;
 }
 
+NS_IMETHODIMP
+inDOMUtils::GetRelativeRuleLine(nsIDOMCSSRule* aRule, uint32_t* _retval)
+{
+  NS_ENSURE_ARG_POINTER(aRule);
+
+  Rule* rule = aRule->GetCSSRule();
+  if (!rule) {
+    return NS_ERROR_FAILURE;
+  }
+
+  uint32_t lineNumber = rule->GetLineNumber();
+  CSSStyleSheet* sheet = rule->GetStyleSheet();
+  if (sheet) {
+    nsINode* owningNode = sheet->GetOwnerNode();
+    if (owningNode) {
+      nsCOMPtr<nsIStyleSheetLinkingElement> link =
+        do_QueryInterface(owningNode);
+      if (link) {
+        lineNumber -= link->GetLineNumber() - 1;
+      }
+    }
+  }
+
+  *_retval = lineNumber;
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 inDOMUtils::GetCSSLexer(const nsAString& aText, JSContext* aCx,
                         JS::MutableHandleValue aResult)
diff --git a/layout/inspector/inIDOMUtils.idl b/layout/inspector/inIDOMUtils.idl
index f9ea98c5100a..1488f219b716 100644
--- a/layout/inspector/inIDOMUtils.idl
+++ b/layout/inspector/inIDOMUtils.idl
@@ -17,7 +17,7 @@ interface nsIDOMFontFaceList;
 interface nsIDOMRange;
 interface nsIDOMCSSStyleSheet;
 
-[scriptable, uuid(60b4cbf7-2a08-4419-8937-6ef495417824)]
+[scriptable, uuid(d67c0463-592e-4d7c-b67e-923ee3f6c643)]
 interface inIDOMUtils : nsISupports
 {
   // CSS utilities
@@ -28,6 +28,16 @@ interface inIDOMUtils : nsISupports
   unsigned long getRuleLine(in nsIDOMCSSRule aRule);
   unsigned long getRuleColumn(in nsIDOMCSSRule aRule);
 
+  /**
+   * Like getRuleLine, but if the rule is in a <style> element,
+   * returns a line number relative to the start of the element.
+   *
+   * @param nsIDOMCSSRule aRule the rule to examine
+   * @return the line number of the rule, possibly relative to the
+   *         <style> element
+   */
+  unsigned long getRelativeRuleLine(in nsIDOMCSSRule aRule);
+
   [implicit_jscontext]
   jsval getCSSLexer(in DOMString aText);
 
diff --git a/layout/inspector/tests/mochitest.ini b/layout/inspector/tests/mochitest.ini
index 2649e707ebb8..3ed632c0b570 100644
--- a/layout/inspector/tests/mochitest.ini
+++ b/layout/inspector/tests/mochitest.ini
@@ -16,6 +16,7 @@ support-files =
 [test_bug1006595.html]
 [test_color_to_rgba.html]
 [test_css_property_is_valid.html]
+[test_getRelativeRuleLine.html]
 [test_get_all_style_sheets.html]
 [test_is_valid_css_color.html]
 [test_isinheritableproperty.html]
diff --git a/layout/inspector/tests/test_getRelativeRuleLine.html b/layout/inspector/tests/test_getRelativeRuleLine.html
new file mode 100644
index 000000000000..ba44f3a7fe63
--- /dev/null
+++ b/layout/inspector/tests/test_getRelativeRuleLine.html
@@ -0,0 +1,67 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test inDOMUtils::getRelativeRuleLine</title>
+  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+  <style>
+    @supports (not (whatever: 72 zq)) {
+      #test {
+	background-color: #f0c;
+      }
+    }
+
+    #test {
+      color: #f0c;
+    }
+  </style>
+  <style>#test { color: red; }</style>
+  <style>
+     @invalidatkeyword {
+     }
+
+     #test {
+       color: blue;
+     }
+  </style>
+  <script type="application/javascript;version=1.8">
+  let utils = SpecialPowers.Cc["@mozilla.org/inspector/dom-utils;1"]
+                           .getService(SpecialPowers.Ci.inIDOMUtils);
+
+  let tests = [
+    { sheetNo: 0, ruleNo: 0, lineNo: 1, columnNo: 1 },
+    { sheetNo: 1, ruleNo: 0, lineNo: 2, columnNo: 15 },
+    { sheetNo: 1, ruleNo: 1, lineNo: 8, columnNo: 5 },
+    { sheetNo: 2, ruleNo: 0, lineNo: 1, columnNo: 1 },
+    { sheetNo: 3, ruleNo: 0, lineNo: 5, columnNo: 6 },
+  ];
+
+  function doTest() {
+    for (let test of tests) {
+      let sheet = document.styleSheets[test.sheetNo];
+      let rule = sheet.cssRules[test.ruleNo];
+      let line = utils.getRelativeRuleLine(rule);
+      let column = utils.getRuleColumn(rule);
+      info("testing sheet " + test.sheetNo + ", rule " + test.ruleNo);
+      is(line, test.lineNo, "line number is correct");
+      is(column, test.columnNo, "column number is correct");
+    }
+
+    SimpleTest.finish();
+  }
+
+  SimpleTest.waitForExplicitFinish();
+  addLoadEvent(doTest);
+  </script>
+</head>
+<body>
+<h1>Test inDOMUtils::getRelativeRuleLine</h1>
+<p id="display"></p>
+<div id="content" style="display: none">
+
+</div>
+<pre id="test">
+</pre>
+</body>
+</html>
diff --git a/toolkit/devtools/server/actors/csscoverage.js b/toolkit/devtools/server/actors/csscoverage.js
index 18b04568708e..3107d06c008d 100644
--- a/toolkit/devtools/server/actors/csscoverage.js
+++ b/toolkit/devtools/server/actors/csscoverage.js
@@ -564,8 +564,9 @@ function getImportedSheets(stylesheet) {
  * @see deconstructRuleId(ruleId)
  */
 function ruleToId(rule) {
-  let loc = stylesheets.getRuleLocation(rule);
-  return sheetToUrl(rule.parentStyleSheet) + "|" + loc.line + "|" + loc.column;
+  let line = DOMUtils.getRelativeRuleLine(rule);
+  let column = DOMUtils.getRuleColumn(rule);
+  return sheetToUrl(rule.parentStyleSheet) + "|" + line + "|" + column;
 }
 
 /**
diff --git a/toolkit/devtools/server/actors/stylesheets.js b/toolkit/devtools/server/actors/stylesheets.js
index 6a277fadf35e..b2e453952263 100644
--- a/toolkit/devtools/server/actors/stylesheets.js
+++ b/toolkit/devtools/server/actors/stylesheets.js
@@ -932,53 +932,6 @@ let StyleSheetActor = protocol.ActorClass({
   }
 })
 
-/**
- * Find the line/column for a rule.
- * This is like DOMUtils.getRule[Line|Column] except for inline <style> sheets,
- * the line number returned here is relative to the <style> tag rather than the
- * containing HTML document (which is what DOMUtils does).
- * This is hacky, but we don't know of a better implementation right now.
- */
-const getRuleLocation = exports.getRuleLocation = function(rule) {
-  let reply = {
-    line: DOMUtils.getRuleLine(rule),
-    column: DOMUtils.getRuleColumn(rule)
-  };
-
-  let sheet = rule.parentStyleSheet;
-  if (sheet.ownerNode && sheet.ownerNode.localName === "style") {
-     // For inline sheets, the line is relative to HTML not the stylesheet, so
-     // Get the location of the first { to know the line num of the first rule,
-     // relative to this sheet, to get the offset
-     let text = sheet.ownerNode.textContent;
-     // Hacky for now, because this will fail if { appears in a comment before
-     // but better than nothing, and faster than parsing the whole text
-     let start = text.substring(0, text.indexOf("{"));
-     let relativeStartLine = start.split("\n").length;
-
-     let absoluteStartLine;
-     let i = 0;
-     while (absoluteStartLine == null) {
-       let irule = sheet.cssRules[i];
-       if (irule instanceof Ci.nsIDOMCSSStyleRule) {
-         absoluteStartLine = DOMUtils.getRuleLine(irule);
-       }
-       else if (irule == null) {
-         break;
-       }
-
-       i++;
-     }
-
-     if (absoluteStartLine != null) {
-       let offset = absoluteStartLine - relativeStartLine;
-       reply.line -= offset;
-     }
-  }
-
-  return reply;
-};
-
 /**
  * StyleSheetFront is the client-side counterpart to a StyleSheetActor.
  */