Auto merge of #15751 - avinash-vijayaraghavan:testing-csserror, r=cbrewster

first stab. added ServoUrl as a parameter to report_error(...) of Par…

@jdm @SimonSapin
<!-- Please describe your changes on the following line: -->

1. Added ServoUrl as a parameter to report_error(...) of ParseErrorReporter trait.
2. I am not sure how to handle the case of impl ParseErrorReporter for CSSErrorReporter and MemoryHoleReporter, so have not made any changes  (other than adding ServoUrl arg) to report_error implementations for these.
3. In StdoutErrorReporter i have added the ServoUrl arg to the info! function,
4. I would like to know if i am on the correct path and clarify what else needs to be done.

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [ X] `./mach build -d` does not report any errors
- [ ] `./mach test-tidy` does not report any errors
- [ ] These changes fix #15708 (github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because wanted to clarify before writing tests

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7 files changed, 36 insertions, 19 deletions

diff --git a/components/script_layout_interface/reporter.rs b/components/script_layout_interface/reporter.rs
index 4561f2d63ca..171f96d9d06 100644
--- a/components/script_layout_interface/reporter.rs
+++ b/components/script_layout_interface/reporter.rs
@@ -7,6 +7,7 @@ use ipc_channel::ipc::IpcSender;
 use log;
 use msg::constellation_msg::PipelineId;
 use script_traits::ConstellationControlMsg;
+use servo_url::ServoUrl;
 use std::sync::{Mutex, Arc};
 use style::error_reporting::ParseErrorReporter;
 
@@ -21,11 +22,13 @@ pub struct CSSErrorReporter {
 }
 
 impl ParseErrorReporter for CSSErrorReporter {
-     fn report_error(&self, input: &mut Parser, position: SourcePosition, message: &str) {
-         let location = input.source_location(position);
-         if log_enabled!(log::LogLevel::Info) {
-             info!("{}:{} {}", location.line, location.column, message)
-         }
+     fn report_error(&self, input: &mut Parser, position: SourcePosition, message: &str,
+        url: &ServoUrl) {
+        let location = input.source_location(position);
+        if log_enabled!(log::LogLevel::Info) {
+             info!("Url:\t{}\n{}:{} {}", url.as_str(), location.line, location.column, message)
+        }
+
          //TODO: report a real filename
          let _ = self.script_chan.lock().unwrap().send(
              ConstellationControlMsg::ReportCSSError(self.pipelineid,
diff --git a/components/style/error_reporting.rs b/components/style/error_reporting.rs
index 3a802bdd6c6..e815d0bf29e 100644
--- a/components/style/error_reporting.rs
+++ b/components/style/error_reporting.rs
@@ -8,6 +8,7 @@
 
 use cssparser::{Parser, SourcePosition};
 use log;
+use servo_url::ServoUrl;
 
 /// A generic trait for an error reporter.
 pub trait ParseErrorReporter {
@@ -15,7 +16,7 @@ pub trait ParseErrorReporter {
     ///
     /// Returns the current input being parsed, the source position it was
     /// reported from, and a message.
-    fn report_error(&self, input: &mut Parser, position: SourcePosition, message: &str);
+    fn report_error(&self, input: &mut Parser, position: SourcePosition, message: &str, url: &ServoUrl);
     /// Clone this error reporter.
     ///
     /// TODO(emilio): I'm pretty sure all the box shenanigans can go away.
@@ -27,11 +28,12 @@ pub trait ParseErrorReporter {
 /// TODO(emilio): The name of this reporter is a lie, and should be renamed!
 pub struct StdoutErrorReporter;
 impl ParseErrorReporter for StdoutErrorReporter {
-    fn report_error(&self, input: &mut Parser, position: SourcePosition, message: &str) {
-         if log_enabled!(log::LogLevel::Info) {
-             let location = input.source_location(position);
-             info!("{}:{} {}", location.line, location.column, message)
-         }
+    fn report_error(&self, input: &mut Parser, position: SourcePosition, message: &str,
+        url: &ServoUrl) {
+        if log_enabled!(log::LogLevel::Info) {
+            let location = input.source_location(position);
+            info!("Url:\t{}\n{}:{} {}", url.as_str(), location.line, location.column, message)
+        }
     }
 
     fn clone(&self) -> Box<ParseErrorReporter + Send + Sync> {
diff --git a/components/style/parser.rs b/components/style/parser.rs
index 4145650b2c8..b561fd6efea 100644
--- a/components/style/parser.rs
+++ b/components/style/parser.rs
@@ -90,7 +90,8 @@ impl<'a> ParserContext<'a> {
 /// Set a `RUST_LOG=style::errors` environment variable
 /// to log CSS parse errors to stderr.
 pub fn log_css_error(input: &mut Parser, position: SourcePosition, message: &str, parsercontext: &ParserContext) {
-    parsercontext.error_reporter.report_error(input, position, message);
+    let servo_url = parsercontext.base_url;
+    parsercontext.error_reporter.report_error(input, position, message, servo_url);
 }
 
 // XXXManishearth Replace all specified value parse impls with impls of this
diff --git a/components/style/stylesheets.rs b/components/style/stylesheets.rs
index be88e22ea7e..6ee7b6843a0 100644
--- a/components/style/stylesheets.rs
+++ b/components/style/stylesheets.rs
@@ -252,7 +252,8 @@ impl ParseErrorReporter for MemoryHoleReporter {
     fn report_error(&self,
             _: &mut Parser,
             _: SourcePosition,
-            _: &str) {
+            _: &str,
+            _: &ServoUrl) {
         // do nothing
     }
     fn clone(&self) -> Box<ParseErrorReporter + Send + Sync> {
diff --git a/tests/unit/style/media_queries.rs b/tests/unit/style/media_queries.rs
index 11e1987928a..b2fe60ea91e 100644
--- a/tests/unit/style/media_queries.rs
+++ b/tests/unit/style/media_queries.rs
@@ -18,8 +18,10 @@ use style_traits::ToCss;
 pub struct CSSErrorReporterTest;
 
 impl ParseErrorReporter for CSSErrorReporterTest {
-     fn report_error(&self, _input: &mut Parser, _position: SourcePosition, _message: &str) {
-     }
+    fn report_error(&self, _input: &mut Parser, _position: SourcePosition, _message: &str,
+        _url: &ServoUrl) {
+    }
+
      fn clone(&self) -> Box<ParseErrorReporter + Send + Sync> {
         Box::new(CSSErrorReporterTest)
      }
diff --git a/tests/unit/style/rule_tree/bench.rs b/tests/unit/style/rule_tree/bench.rs
index de68d99b71d..fccab1252f9 100644
--- a/tests/unit/style/rule_tree/bench.rs
+++ b/tests/unit/style/rule_tree/bench.rs
@@ -17,8 +17,9 @@ use test::{self, Bencher};
 
 struct ErrorringErrorReporter;
 impl ParseErrorReporter for ErrorringErrorReporter {
-    fn report_error(&self, _: &mut Parser, position: SourcePosition, message: &str) {
-        panic!("CSS error: {:?} {}", position, message);
+    fn report_error(&self, input: &mut Parser, position: SourcePosition, message: &str,
+        url: &ServoUrl) {
+        panic!("CSS error: {}\t\n{:?} {}", url.as_str(), position, message);
     }
 
     fn clone(&self) -> Box<ParseErrorReporter + Send + Sync> {
diff --git a/tests/unit/style/stylesheets.rs b/tests/unit/style/stylesheets.rs
index 83166e019e5..586f2616ecf 100644
--- a/tests/unit/style/stylesheets.rs
+++ b/tests/unit/style/stylesheets.rs
@@ -276,6 +276,7 @@ fn test_parse_stylesheet() {
 }
 
 struct CSSError {
+    pub url : ServoUrl,
     pub line: usize,
     pub column: usize,
     pub message: String
@@ -294,7 +295,9 @@ impl CSSInvalidErrorReporterTest {
 }
 
 impl ParseErrorReporter for CSSInvalidErrorReporterTest {
-    fn report_error(&self, input: &mut CssParser, position: SourcePosition, message: &str) {
+    fn report_error(&self, input: &mut CssParser, position: SourcePosition, message: &str,
+        url: &ServoUrl) {
+
         let location = input.source_location(position);
 
         let errors = self.errors.clone();
@@ -302,6 +305,7 @@ impl ParseErrorReporter for CSSInvalidErrorReporterTest {
 
         errors.push(
             CSSError{
+                url: url.clone(),
                 line: location.line,
                 column: location.column,
                 message: message.to_owned()
@@ -333,7 +337,7 @@ fn test_report_error_stylesheet() {
 
     let errors = error_reporter.errors.clone();
 
-    Stylesheet::from_str(css, url, Origin::UserAgent, Default::default(),
+    Stylesheet::from_str(css, url.clone(), Origin::UserAgent, Default::default(),
                          None,
                          error_reporter,
                          ParserContextExtraData::default());
@@ -349,4 +353,7 @@ fn test_report_error_stylesheet() {
     assert_eq!("Unsupported property declaration: 'display: invalid;'", error.message);
     assert_eq!(4, error.line);
     assert_eq!(9, error.column);
+
+    // testing for the url
+    assert_eq!(url, error.url);
 }