Auto merge of #15613 - Varentsov:master, r=upsuper

fix {transform,perspective}-origin accepts (and ignores) anything for…

… their second part of value

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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 #15487.

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- [X] There are tests for these changes OR

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

@@ -487,7 +487,7 @@ pub fn parse_origin(context: &ParserContext, input: &mut Parser) -> Result<Origi
             }
             Ok(())
         }) {
-            match LengthOrPercentage::parse(context, input) {
+            match input.try(|input| LengthOrPercentage::parse(context, input)) {
                 Ok(value) => {
                     if horizontal.is_none() {
                         horizontal = Some(value);

tests/unit/style/parsing/effects.rs

@@ -6,6 +6,7 @@ use cssparser::Parser;
 use media_queries::CSSErrorReporterTest;
 use servo_url::ServoUrl;
 use style::parser::ParserContext;
+use style::properties::longhands::{self, perspective_origin, transform_origin};
 use style::stylesheets::Origin;
 use style_traits::ToCss;
 
@@ -33,3 +34,32 @@ fn test_clip() {
                                    "rect(auto, auto, auto, auto)");
 }
 
+#[test]
+fn test_longhands_parse_origin() {
+    let url = ServoUrl::parse("http://localhost").unwrap();
+    let context = ParserContext::new(Origin::Author, &url, Box::new(CSSErrorReporterTest));
+
+    let mut parser = Parser::new("1px some-rubbish");
+    let parsed = longhands::parse_origin(&context, &mut parser);
+    assert!(parsed.is_ok());
+    assert_eq!(parser.is_exhausted(), false);
+
+    let mut parser = Parser::new("1px 2px");
+    let parsed = longhands::parse_origin(&context, &mut parser);
+    assert!(parsed.is_ok());
+    assert_eq!(parser.is_exhausted(), true);
+
+    let mut parser = Parser::new("1px");
+    let parsed = longhands::parse_origin(&context, &mut parser);
+    assert!(parsed.is_ok());
+    assert_eq!(parser.is_exhausted(), true);
+}
+
+#[test]
+fn test_effects_parser_exhaustion() {
+    assert_parser_exhausted!(perspective_origin, "1px 1px", true);
+    assert_parser_exhausted!(transform_origin, "1px 1px", true);
+
+    assert_parser_exhausted!(perspective_origin, "1px some-rubbish", false);
+    assert_parser_exhausted!(transform_origin, "1px some-rubbish", false);
+}