Auto merge of #15357 - dashed:gh-15207, r=Wafflespeanut,emilio

Refactor outline-style to accept "auto" value in addition to border-style values.

Fixes https://github.com/servo/servo/issues/15207

Refactored as per https://github.com/servo/servo/issues/15207#issuecomment-275171590 .

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

- [x] Correct refactor? I'd appreciate any feedback on this.
- [x] ~~~proper borderstyle value for `outline-style: auto;`?~~~ ~~~(EDIT: deferred to a `FIXME`)~~~ (EDIT2: it is now solid for behaviour parity with firefox)
- [x] squash pending PR review
- [x] mako code review

---
<!-- 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
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #15207 (github issue number if applicable).

<!-- Either: -->
- [x] There are tests for these changes

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tests/unit/style/parsing/border.rs

@@ -5,11 +5,12 @@
 use cssparser::Parser;
 use media_queries::CSSErrorReporterTest;
 use servo_url::ServoUrl;
-use style::parser::ParserContext;
+use style::parser::{ParserContext, Parse};
 use style::properties::longhands::{border_image_outset, border_image_repeat, border_image_slice};
 use style::properties::longhands::{border_image_source, border_image_width};
 use style::properties::shorthands::border_image;
 use style::stylesheets::Origin;
+use style_traits::ToCss;
 
 #[test]
 fn border_image_shorthand_should_parse_when_all_properties_specified() {
@@ -122,3 +123,19 @@ fn border_image_outset_should_return_length_on_length_zero() {
     let result = border_image_outset::parse(&context, &mut parser);
     assert_eq!(result.unwrap(), parse_longhand!(border_image_outset, "0em"));
 }
+
+#[test]
+fn test_border_style() {
+    use style::values::specified::BorderStyle;
+
+    assert_roundtrip_with_context!(BorderStyle::parse, r#"none"#);
+    assert_roundtrip_with_context!(BorderStyle::parse, r#"hidden"#);
+    assert_roundtrip_with_context!(BorderStyle::parse, r#"solid"#);
+    assert_roundtrip_with_context!(BorderStyle::parse, r#"double"#);
+    assert_roundtrip_with_context!(BorderStyle::parse, r#"dotted"#);
+    assert_roundtrip_with_context!(BorderStyle::parse, r#"dashed"#);
+    assert_roundtrip_with_context!(BorderStyle::parse, r#"groove"#);
+    assert_roundtrip_with_context!(BorderStyle::parse, r#"ridge"#);
+    assert_roundtrip_with_context!(BorderStyle::parse, r#"inset"#);
+    assert_roundtrip_with_context!(BorderStyle::parse, r#"outset"#);
+}

tests/unit/style/parsing/mod.rs

@@ -75,6 +75,7 @@ mod image;
 mod inherited_box;
 mod inherited_text;
 mod mask;
+mod outline;
 mod position;
 mod selectors;
 mod supports;

tests/unit/style/parsing/outline.rs

@@ -0,0 +1,37 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * 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 media_queries::CSSErrorReporterTest;
+use style::parser::ParserContext;
+use style::stylesheets::Origin;
+use style_traits::ToCss;
+
+#[test]
+fn test_outline_style() {
+    use style::properties::longhands::outline_style;
+
+    assert_roundtrip_with_context!(outline_style::parse, r#"auto"#);
+    assert_roundtrip_with_context!(outline_style::parse, r#"none"#);
+    assert_roundtrip_with_context!(outline_style::parse, r#"solid"#);
+    assert_roundtrip_with_context!(outline_style::parse, r#"double"#);
+    assert_roundtrip_with_context!(outline_style::parse, r#"dotted"#);
+    assert_roundtrip_with_context!(outline_style::parse, r#"dashed"#);
+    assert_roundtrip_with_context!(outline_style::parse, r#"groove"#);
+    assert_roundtrip_with_context!(outline_style::parse, r#"ridge"#);
+    assert_roundtrip_with_context!(outline_style::parse, r#"inset"#);
+    assert_roundtrip_with_context!(outline_style::parse, r#"outset"#);
+
+    {
+        // The outline-style property accepts the same values as border-style,
+        // except that 'hidden' is not a legal outline style.
+
+        let url = ::servo_url::ServoUrl::parse("http://localhost").unwrap();
+        let context = ParserContext::new(Origin::Author, &url, Box::new(CSSErrorReporterTest));
+        let mut parser = Parser::new(r#"hidden"#);
+        let parsed = outline_style::parse(&context, &mut parser);
+        assert!(parsed.is_err());
+    };
+
+}

tests/unit/style/properties/serialization.rs

@@ -8,7 +8,8 @@ pub use style::properties::{DeclaredValue, PropertyDeclaration, PropertyDeclarat
 pub use style::values::specified::{BorderStyle, BorderWidth, CSSColor, Length, NoCalcLength};
 pub use style::values::specified::{LengthOrPercentage, LengthOrPercentageOrAuto, LengthOrPercentageOrAutoOrContent};
 pub use style::properties::longhands::outline_color::computed_value::T as ComputedColor;
-pub use style::values::RGBA;
+pub use style::properties::longhands::outline_style::SpecifiedValue as OutlineStyle;
+pub use style::values::{RGBA, Auto};
 pub use style::values::specified::url::{UrlExtraData, SpecifiedUrl};
 pub use style_traits::ToCss;
 
@@ -459,6 +460,7 @@ mod shorthand_serialization {
 
     mod outline {
         use style::properties::longhands::outline_width::SpecifiedValue as WidthContainer;
+        use style::values::Either;
         use super::*;
 
         #[test]
@@ -466,7 +468,7 @@ mod shorthand_serialization {
             let mut properties = Vec::new();
 
             let width = DeclaredValue::Value(WidthContainer(Length::from_px(4f32)));
-            let style = DeclaredValue::Value(BorderStyle::solid);
+            let style = DeclaredValue::Value(Either::Second(BorderStyle::solid));
             let color = DeclaredValue::Value(CSSColor {
                 parsed: ComputedColor::RGBA(RGBA { red: 1f32, green: 0f32, blue: 0f32, alpha: 1f32 }),
                 authored: None
@@ -485,7 +487,7 @@ mod shorthand_serialization {
             let mut properties = Vec::new();
 
             let width = DeclaredValue::Value(WidthContainer(Length::from_px(4f32)));
-            let style = DeclaredValue::Value(BorderStyle::solid);
+            let style = DeclaredValue::Value(Either::Second(BorderStyle::solid));
             let color = DeclaredValue::Initial;
 
             properties.push(PropertyDeclaration::OutlineWidth(width));
@@ -513,6 +515,24 @@ mod shorthand_serialization {
             let serialization = shorthand_properties_to_string(properties);
             assert_eq!(serialization, "outline: 4px none rgb(255, 0, 0);");
         }
+
+        #[test]
+        fn outline_should_serialize_correctly_when_style_is_auto() {
+            let mut properties = Vec::new();
+
+            let width = DeclaredValue::Value(WidthContainer(Length::from_px(4f32)));
+            let style = DeclaredValue::Value(Either::First(Auto));
+            let color = DeclaredValue::Value(CSSColor {
+                parsed: ComputedColor::RGBA(RGBA { red: 1f32, green: 0f32, blue: 0f32, alpha: 1f32 }),
+                authored: None
+            });
+            properties.push(PropertyDeclaration::OutlineWidth(width));
+            properties.push(PropertyDeclaration::OutlineStyle(style));
+            properties.push(PropertyDeclaration::OutlineColor(color));
+
+            let serialization = shorthand_properties_to_string(properties);
+            assert_eq!(serialization, "outline: 4px auto rgb(255, 0, 0);");
+        }
     }
 
     #[test]