Auto merge of #16067 - Wafflespeanut:grid, r=nox,Wafflespeanut

Stylo: Add support for grid-template-{rows,columns}

This has the implementation of grid's `<track-list>` nightmare.

---
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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 #15311

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- [x] There are tests for these changes

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tests/unit/style/parsing/mod.rs

@@ -5,10 +5,16 @@
 //! Tests for parsing and serialization of values/properties
 
 use cssparser::Parser;
+use euclid::size::TypedSize2D;
 use media_queries::CSSErrorReporterTest;
 use style::context::QuirksMode;
+use style::font_metrics::ServoMetricsProvider;
+use style::media_queries::{Device, MediaType};
 use style::parser::{PARSING_MODE_DEFAULT, ParserContext};
+use style::properties::{ComputedValues, StyleBuilder};
 use style::stylesheets::{CssRuleType, Origin};
+use style::values::computed::{Context, ToComputedValue};
+use style_traits::ToCss;
 
 fn parse<T, F: Fn(&ParserContext, &mut Parser) -> Result<T, ()>>(f: F, s: &str) -> Result<T, ()> {
     let url = ::servo_url::ServoUrl::parse("http://localhost").unwrap();
@@ -24,6 +30,32 @@ fn parse_entirely<T, F: Fn(&ParserContext, &mut Parser) -> Result<T, ()>>(f: F,
     parse(|context, parser| parser.parse_entirely(|p| f(context, p)), s)
 }
 
+fn assert_computed_serialization<C, F, T>(f: F, input: &str, output: &str)
+    where F: Fn(&ParserContext, &mut Parser) -> Result<T, ()>,
+          T: ToComputedValue<ComputedValue=C>, C: ToCss
+{
+    let viewport_size = TypedSize2D::new(0., 0.);
+    let initial_style = ComputedValues::initial_values();
+    let device = Device::new(MediaType::Screen, viewport_size);
+
+    let context = Context {
+        is_root_element: true,
+        device: &device,
+        inherited_style: initial_style,
+        layout_parent_style: initial_style,
+        style: StyleBuilder::for_derived_style(&initial_style),
+        cached_system_font: None,
+        font_metrics_provider: &ServoMetricsProvider,
+        in_media_query: false,
+        quirks_mode: QuirksMode::NoQuirks,
+    };
+
+    let parsed = parse(f, input).unwrap();
+    let computed = parsed.to_computed_value(&context);
+    let serialized = ToCss::to_css_string(&computed);
+    assert_eq!(serialized, output);
+}
+
 // This is a macro so that the file/line information
 // is preserved in the panic
 macro_rules! assert_roundtrip_with_context {

tests/unit/style/parsing/position.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 parsing::{parse, parse_entirely};
+use parsing::{assert_computed_serialization, parse, parse_entirely};
 use style::parser::Parse;
 use style::values::specified::position::*;
 use style_traits::ToCss;
@@ -168,3 +168,68 @@ fn test_grid_auto_flow() {
     assert!(parse(grid_auto_flow::parse, "column 'dense'").is_err());
     assert!(parse(grid_auto_flow::parse, "column 2px dense").is_err());
 }
+
+#[test]
+fn test_grid_auto_rows_columns() {
+    use style::properties::longhands::grid_auto_rows;
+
+    // the grammar is <track-size>+ but gecko supports only a single value, so we've clamped ourselves
+    assert_roundtrip_with_context!(grid_auto_rows::parse, "55%");
+    assert_roundtrip_with_context!(grid_auto_rows::parse, "0.5fr");
+    assert_roundtrip_with_context!(grid_auto_rows::parse, "fit-content(11%)");
+    // only <inflexible-breadth> is allowed in first arg of minmax
+    assert!(parse(grid_auto_rows::parse, "minmax(1fr, max-content)").is_err());
+}
+
+#[test]
+fn test_grid_template_rows_columns() {
+    use style::properties::longhands::grid_template_rows;
+
+    assert_roundtrip_with_context!(grid_template_rows::parse, "none");      // none keyword
+    // <track-size>{2} with `<track-breadth> minmax(<inflexible-breadth>, <track-breadth>)`
+    assert_roundtrip_with_context!(grid_template_rows::parse, "1fr minmax(min-content, 1fr)");
+    // <track-size> with <track-breadth> as <length-percentage>
+    assert_roundtrip_with_context!(grid_template_rows::parse, "calc(4em + 5px)");
+    // <track-size> with <length> followed by <track-repeat> with `<track-size>{3}` (<flex>, auto, minmax)
+    assert_roundtrip_with_context!(grid_template_rows::parse, "10px repeat(2, 1fr auto minmax(200px, 1fr))");
+    // <track-repeat> with `<track-size> <line-names>` followed by <track-size>
+    assert_roundtrip_with_context!(grid_template_rows::parse, "repeat(4, 10px [col-start] 250px [col-end]) 10px");
+    // mixture of <track-size>, <track-repeat> and <line-names>
+    assert_roundtrip_with_context!(grid_template_rows::parse,
+        "[a] auto [b] minmax(min-content, 1fr) [b c d] repeat(2, [e] 40px) repeat(5, [f g] auto [h]) [i]");
+
+    // no span allowed in <line-names>
+    assert!(parse(grid_template_rows::parse, "[a span] 10px").is_err());
+    // <track-list> needs at least one <track-size> | <track-repeat>
+    assert!(parse(grid_template_rows::parse, "[a b c]").is_err());
+    // at least one argument of <fixed-size> should be a <fixed-breadth> (i.e., <length-percentage>)
+    assert!(parse(grid_template_rows::parse, "[a b] repeat(auto-fill, 50px) minmax(auto, 1fr)").is_err());
+    // fit-content is not a <fixed-size>
+    assert!(parse(grid_template_rows::parse, "[a b] repeat(auto-fill, fit-content(20%))").is_err());
+    // <auto-track-list> only allows <fixed-size> | <fixed-repeat>
+    assert!(parse(grid_template_rows::parse, "[a] repeat(2, auto) repeat(auto-fill, 10px)").is_err());
+    // only <inflexible-breadth> allowed in <auto-track-repeat>
+    assert!(parse(grid_template_rows::parse, "[a] repeat(auto-fill, 1fr)").is_err());
+    // <auto-track-repeat> is allowed only once
+    assert!(parse(grid_template_rows::parse, "[a] repeat(auto-fit, [b] 8px) [c] repeat(auto-fill, [c] 8px)").is_err());
+}
+
+#[test]
+fn test_computed_grid_template_rows_colums() {
+    use style::properties::longhands::grid_template_rows;
+
+    assert_computed_serialization(grid_template_rows::parse,
+        "[a] repeat(calc(1 + 1), [b] auto)", "[a b] auto [b] auto");
+
+    assert_computed_serialization(grid_template_rows::parse,
+        "[a] repeat(2, [b c] auto [e] auto [d])",
+        "[a b c] auto [e] auto [d b c] auto [e] auto [d]");
+
+    assert_computed_serialization(grid_template_rows::parse,
+        "[a] 50px [b] 10% [b c d] repeat(2, [e] 40px [f]) [g] repeat(auto-fill, [h i] 20px [j]) [k] 10px [l]",
+        "[a] 50px [b] 10% [b c d e] 40px [f e] 40px [f g] repeat(auto-fill, [h i] 20px [j]) [k] 10px [l]");
+
+    assert_computed_serialization(grid_template_rows::parse,
+        "10px repeat(2, 1fr auto minmax(200px, 1fr))",
+        "10px minmax(auto, 1fr) auto minmax(200px, 1fr) minmax(auto, 1fr) auto minmax(200px, 1fr)");
+}