Auto merge of #16752 - jdm:css-parse-error, r=SimonSapin

Report more informative CSS errors

This requires https://github.com/servo/rust-cssparser/pull/143 for the final commit. There's no better way to split that work up, unfortunately, and it's extremely easy to bitrot. I would appreciate if we could expedite reviewing this work.

This is the work necessary to enable https://bugzilla.mozilla.org/show_bug.cgi?id=1352669. It makes sense to merge it separately because it's so much effort to keep it up to date with the ongoing Stylo work.

---
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [x] There are tests for these changes

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---
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12 files changed, 40 insertions, 27 deletions

diff --git a/components/script/dom/canvasgradient.rs b/components/script/dom/canvasgradient.rs
index 994582f509b..64df591f760 100644
--- a/components/script/dom/canvasgradient.rs
+++ b/components/script/dom/canvasgradient.rs
@@ -3,7 +3,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use canvas_traits::{CanvasGradientStop, FillOrStrokeStyle, LinearGradientStyle, RadialGradientStyle};
-use cssparser::{Parser, RGBA};
+use cssparser::{Parser, ParserInput, RGBA};
 use cssparser::Color as CSSColor;
 use dom::bindings::cell::DOMRefCell;
 use dom::bindings::codegen::Bindings::CanvasGradientBinding;
@@ -53,7 +53,8 @@ impl CanvasGradientMethods for CanvasGradient {
             return Err(Error::IndexSize);
         }
 
-        let mut parser = Parser::new(&color);
+        let mut input = ParserInput::new(&color);
+        let mut parser = Parser::new(&mut input);
         let color = CSSColor::parse(&mut parser);
         let color = if parser.is_exhausted() {
             match color {
diff --git a/components/script/dom/canvasrenderingcontext2d.rs b/components/script/dom/canvasrenderingcontext2d.rs
index 348ec08aced..8fb17c90fea 100644
--- a/components/script/dom/canvasrenderingcontext2d.rs
+++ b/components/script/dom/canvasrenderingcontext2d.rs
@@ -6,7 +6,7 @@ use canvas_traits::{Canvas2dMsg, CanvasCommonMsg, CanvasMsg};
 use canvas_traits::{CompositionOrBlending, FillOrStrokeStyle, FillRule};
 use canvas_traits::{LineCapStyle, LineJoinStyle, LinearGradientStyle};
 use canvas_traits::{RadialGradientStyle, RepetitionStyle, byte_swap_and_premultiply};
-use cssparser::{Parser, RGBA};
+use cssparser::{Parser, ParserInput, RGBA};
 use cssparser::Color as CSSColor;
 use dom::bindings::cell::DOMRefCell;
 use dom::bindings::codegen::Bindings::CSSStyleDeclarationBinding::CSSStyleDeclarationMethods;
@@ -463,7 +463,8 @@ impl CanvasRenderingContext2D {
     }
 
     fn parse_color(&self, string: &str) -> Result<RGBA, ()> {
-        let mut parser = Parser::new(&string);
+        let mut input = ParserInput::new(string);
+        let mut parser = Parser::new(&mut input);
         let color = CSSColor::parse(&mut parser);
         if parser.is_exhausted() {
             match color {
@@ -1314,7 +1315,8 @@ impl Drop for CanvasRenderingContext2D {
 }
 
 pub fn parse_color(string: &str) -> Result<RGBA, ()> {
-    let mut parser = Parser::new(&string);
+    let mut input = ParserInput::new(string);
+    let mut parser = Parser::new(&mut input);
     match CSSColor::parse(&mut parser) {
         Ok(CSSColor::RGBA(rgba)) => {
             if parser.is_exhausted() {
diff --git a/components/script/dom/css.rs b/components/script/dom/css.rs
index 521c09ed4c2..66f522b2371 100644
--- a/components/script/dom/css.rs
+++ b/components/script/dom/css.rs
@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use cssparser::{Parser, serialize_identifier};
+use cssparser::{Parser, ParserInput, serialize_identifier};
 use dom::bindings::codegen::Bindings::WindowBinding::WindowBinding::WindowMethods;
 use dom::bindings::error::Fallible;
 use dom::bindings::reflector::Reflector;
@@ -39,7 +39,8 @@ impl CSS {
 
     /// https://drafts.csswg.org/css-conditional/#dom-css-supports
     pub fn Supports_(win: &Window, condition: DOMString) -> bool {
-        let mut input = Parser::new(&condition);
+        let mut input = ParserInput::new(&condition);
+        let mut input = Parser::new(&mut input);
         let cond = parse_condition_or_declaration(&mut input);
         if let Ok(cond) = cond {
             let url = win.Document().url();
diff --git a/components/script/dom/csskeyframesrule.rs b/components/script/dom/csskeyframesrule.rs
index 42cb4b374fa..469f9b7d026 100644
--- a/components/script/dom/csskeyframesrule.rs
+++ b/components/script/dom/csskeyframesrule.rs
@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use cssparser::Parser;
+use cssparser::{Parser, ParserInput};
 use dom::bindings::codegen::Bindings::CSSKeyframesRuleBinding;
 use dom::bindings::codegen::Bindings::CSSKeyframesRuleBinding::CSSKeyframesRuleMethods;
 use dom::bindings::error::ErrorResult;
@@ -58,7 +58,8 @@ impl CSSKeyframesRule {
 
     /// Given a keyframe selector, finds the index of the first corresponding rule if any
     fn find_rule(&self, selector: &str) -> Option<usize> {
-        let mut input = Parser::new(selector);
+        let mut input = ParserInput::new(selector);
+        let mut input = Parser::new(&mut input);
         if let Ok(sel) = KeyframeSelector::parse(&mut input) {
             let guard = self.cssrule.shared_lock().read();
             // This finds the *last* element matching a selector
diff --git a/components/script/dom/cssmediarule.rs b/components/script/dom/cssmediarule.rs
index 6986b0fe03d..1f5535f1b3e 100644
--- a/components/script/dom/cssmediarule.rs
+++ b/components/script/dom/cssmediarule.rs
@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use cssparser::Parser;
+use cssparser::{Parser, ParserInput};
 use dom::bindings::codegen::Bindings::CSSMediaRuleBinding;
 use dom::bindings::codegen::Bindings::CSSMediaRuleBinding::CSSMediaRuleMethods;
 use dom::bindings::codegen::Bindings::WindowBinding::WindowBinding::WindowMethods;
@@ -69,7 +69,8 @@ impl CSSMediaRule {
 
     /// https://drafts.csswg.org/css-conditional-3/#the-cssmediarule-interface
     pub fn set_condition_text(&self, text: DOMString) {
-        let mut input = Parser::new(&text);
+        let mut input = ParserInput::new(&text);
+        let mut input = Parser::new(&mut input);
         let global = self.global();
         let win = global.as_window();
         let url = win.get_url();
diff --git a/components/script/dom/csssupportsrule.rs b/components/script/dom/csssupportsrule.rs
index 5d01c2cfdd3..2897b47b35f 100644
--- a/components/script/dom/csssupportsrule.rs
+++ b/components/script/dom/csssupportsrule.rs
@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use cssparser::Parser;
+use cssparser::{Parser, ParserInput};
 use dom::bindings::codegen::Bindings::CSSSupportsRuleBinding;
 use dom::bindings::codegen::Bindings::WindowBinding::WindowBinding::WindowMethods;
 use dom::bindings::js::Root;
@@ -55,7 +55,8 @@ impl CSSSupportsRule {
 
     /// https://drafts.csswg.org/css-conditional-3/#the-csssupportsrule-interface
     pub fn set_condition_text(&self, text: DOMString) {
-        let mut input = Parser::new(&text);
+        let mut input = ParserInput::new(&text);
+        let mut input = Parser::new(&mut input);
         let cond = SupportsCondition::parse(&mut input);
         if let Ok(cond) = cond {
             let global = self.global();
diff --git a/components/script/dom/element.rs b/components/script/dom/element.rs
index 189410ce77a..b4e7be3203a 100644
--- a/components/script/dom/element.rs
+++ b/components/script/dom/element.rs
@@ -2061,7 +2061,7 @@ impl ElementMethods for Element {
     // https://dom.spec.whatwg.org/#dom-element-matches
     fn Matches(&self, selectors: DOMString) -> Fallible<bool> {
         match SelectorParser::parse_author_origin_no_namespace(&selectors) {
-            Err(()) => Err(Error::Syntax),
+            Err(_) => Err(Error::Syntax),
             Ok(selectors) => {
                 let mut ctx = MatchingContext::new(MatchingMode::Normal, None);
                 Ok(matches_selector_list(&selectors, &Root::from_ref(self), &mut ctx))
@@ -2077,7 +2077,7 @@ impl ElementMethods for Element {
     // https://dom.spec.whatwg.org/#dom-element-closest
     fn Closest(&self, selectors: DOMString) -> Fallible<Option<Root<Element>>> {
         match SelectorParser::parse_author_origin_no_namespace(&selectors) {
-            Err(()) => Err(Error::Syntax),
+            Err(_) => Err(Error::Syntax),
             Ok(selectors) => {
                 let root = self.upcast::<Node>();
                 for element in root.inclusive_ancestors() {
diff --git a/components/script/dom/htmllinkelement.rs b/components/script/dom/htmllinkelement.rs
index fc1783985f8..da004317179 100644
--- a/components/script/dom/htmllinkelement.rs
+++ b/components/script/dom/htmllinkelement.rs
@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use cssparser::Parser as CssParser;
+use cssparser::{Parser as CssParser, ParserInput};
 use dom::attr::Attr;
 use dom::bindings::cell::DOMRefCell;
 use dom::bindings::codegen::Bindings::DOMTokenListBinding::DOMTokenListBinding::DOMTokenListMethods;
@@ -278,7 +278,8 @@ impl HTMLLinkElement {
             None => "",
         };
 
-        let mut css_parser = CssParser::new(&mq_str);
+        let mut input = ParserInput::new(&mq_str);
+        let mut css_parser = CssParser::new(&mut input);
         let win = document.window();
         let doc_url = document.url();
         let context = CssParserContext::new_for_cssom(&doc_url, win.css_error_reporter(), Some(CssRuleType::Media),
diff --git a/components/script/dom/htmlstyleelement.rs b/components/script/dom/htmlstyleelement.rs
index 9f7a36c040c..4067cb7439d 100644
--- a/components/script/dom/htmlstyleelement.rs
+++ b/components/script/dom/htmlstyleelement.rs
@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use cssparser::Parser as CssParser;
+use cssparser::{Parser as CssParser, ParserInput};
 use dom::bindings::cell::DOMRefCell;
 use dom::bindings::codegen::Bindings::HTMLStyleElementBinding;
 use dom::bindings::codegen::Bindings::HTMLStyleElementBinding::HTMLStyleElementMethods;
@@ -91,8 +91,9 @@ impl HTMLStyleElement {
                                                       PARSING_MODE_DEFAULT,
                                                       doc.quirks_mode());
         let shared_lock = node.owner_doc().style_shared_lock().clone();
+        let mut input = ParserInput::new(&mq_str);
         let mq = Arc::new(shared_lock.wrap(
-                    parse_media_query_list(&context, &mut CssParser::new(&mq_str))));
+                    parse_media_query_list(&context, &mut CssParser::new(&mut input))));
         let loader = StylesheetLoader::for_element(self.upcast());
         let sheet = Stylesheet::from_str(&data, win.get_url(), Origin::Author, mq,
                                          shared_lock, Some(&loader),
diff --git a/components/script/dom/medialist.rs b/components/script/dom/medialist.rs
index 8915615ca37..d77af9dc1b9 100644
--- a/components/script/dom/medialist.rs
+++ b/components/script/dom/medialist.rs
@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use cssparser::Parser;
+use cssparser::{Parser, ParserInput};
 use dom::bindings::codegen::Bindings::MediaListBinding;
 use dom::bindings::codegen::Bindings::MediaListBinding::MediaListMethods;
 use dom::bindings::codegen::Bindings::WindowBinding::WindowBinding::WindowMethods;
@@ -71,7 +71,8 @@ impl MediaListMethods for MediaList {
             return;
         }
         // Step 3
-        let mut parser = Parser::new(&value);
+        let mut input = ParserInput::new(&value);
+        let mut parser = Parser::new(&mut input);
         let global = self.global();
         let win = global.as_window();
         let url = win.get_url();
@@ -107,7 +108,8 @@ impl MediaListMethods for MediaList {
     // https://drafts.csswg.org/cssom/#dom-medialist-appendmedium
     fn AppendMedium(&self, medium: DOMString) {
         // Step 1
-        let mut parser = Parser::new(&medium);
+        let mut input = ParserInput::new(&medium);
+        let mut parser = Parser::new(&mut input);
         let global = self.global();
         let win = global.as_window();
         let url = win.get_url();
@@ -135,7 +137,8 @@ impl MediaListMethods for MediaList {
     // https://drafts.csswg.org/cssom/#dom-medialist-deletemedium
     fn DeleteMedium(&self, medium: DOMString) {
         // Step 1
-        let mut parser = Parser::new(&medium);
+        let mut input = ParserInput::new(&medium);
+        let mut parser = Parser::new(&mut input);
         let global = self.global();
         let win = global.as_window();
         let url = win.get_url();
diff --git a/components/script/dom/node.rs b/components/script/dom/node.rs
index 8dde9cc7b01..ec0a1117669 100644
--- a/components/script/dom/node.rs
+++ b/components/script/dom/node.rs
@@ -717,7 +717,7 @@ impl Node {
         // Step 1.
         match SelectorParser::parse_author_origin_no_namespace(&selectors) {
             // Step 2.
-            Err(()) => Err(Error::Syntax),
+            Err(_) => Err(Error::Syntax),
             // Step 3.
             Ok(selectors) => {
                 let mut ctx = MatchingContext::new(MatchingMode::Normal, None);
@@ -737,7 +737,7 @@ impl Node {
         // Step 1.
         match SelectorParser::parse_author_origin_no_namespace(&selectors) {
             // Step 2.
-            Err(()) => Err(Error::Syntax),
+            Err(_) => Err(Error::Syntax),
             // Step 3.
             Ok(selectors) => {
                 let mut descendants = self.traverse_preorder();
diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index e627721bd05..bcc5a749d33 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -5,7 +5,7 @@
 use app_units::Au;
 use base64;
 use bluetooth_traits::BluetoothRequest;
-use cssparser::Parser;
+use cssparser::{Parser, ParserInput};
 use devtools_traits::{ScriptToDevtoolsControlMsg, TimelineMarker, TimelineMarkerType};
 use dom::bindings::cell::DOMRefCell;
 use dom::bindings::codegen::Bindings::DocumentBinding::{DocumentMethods, DocumentReadyState};
@@ -1003,7 +1003,8 @@ impl WindowMethods for Window {
 
     // https://drafts.csswg.org/cssom-view/#dom-window-matchmedia
     fn MatchMedia(&self, query: DOMString) -> Root<MediaQueryList> {
-        let mut parser = Parser::new(&query);
+        let mut input = ParserInput::new(&query);
+        let mut parser = Parser::new(&mut input);
         let url = self.get_url();
         let quirks_mode = self.Document().quirks_mode();
         let context = CssParserContext::new_for_cssom(&url, self.css_error_reporter(), Some(CssRuleType::Media),