Auto merge of #15598 - abhiQmar:master, r=canaltinova

text-overflow accepts only valid values for the second part of value

… value #15491

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #15491.

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- [X] There are tests for these changes

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components/style/properties/longhand/text.mako.rs

@@ -51,7 +51,7 @@
     }
     pub fn parse(context: &ParserContext, input: &mut Parser) -> Result<SpecifiedValue, ()> {
         let first = try!(Side::parse(context, input));
-        let second = Side::parse(context, input).ok();
+        let second = input.try(|input| Side::parse(context, input)).ok();
         Ok(SpecifiedValue {
             first: first,
             second: second,

tests/unit/style/parsing/text_overflow.rs

@@ -22,3 +22,13 @@ fn test_text_overflow() {
     assert_roundtrip_with_context!(text_overflow::parse, r#""x" "y""#);
 
 }
+
+#[test]
+fn test_text_overflow_parser_exhaustion() {
+    use style::properties::longhands::text_overflow;
+
+    assert_parser_exhausted!(text_overflow, r#"clip rubbish"#, false);
+    assert_parser_exhausted!(text_overflow, r#"clip"#, true);
+    assert_parser_exhausted!(text_overflow, r#"ellipsis"#, true);
+    assert_parser_exhausted!(text_overflow, r#"clip ellipsis"#, true);
+}