Auto merge of #19378 - CYBAI:grid-auto-flow-out-of-mako, r=emilio

style: Move grid-auto-flow outside of mako

This is a sub-PR of #19015
r? emilio

---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #19375
- [x] These changes do not require tests

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

@@ -293,128 +293,13 @@ ${helpers.predefined_type("object-position",
 
 % endfor
 
-<%helpers:longhand name="grid-auto-flow"
-        spec="https://drafts.csswg.org/css-grid/#propdef-grid-auto-flow"
-        products="gecko"
-        gecko_pref="layout.css.grid.enabled"
-        animation_value_type="discrete">
-    use std::fmt;
-    use style_traits::ToCss;
-
-    pub type SpecifiedValue = computed_value::T;
-
-    pub mod computed_value {
-        #[derive(Clone, Copy, Debug, Eq, MallocSizeOf, PartialEq, ToComputedValue)]
-        pub enum AutoFlow {
-            Row,
-            Column,
-        }
-
-        #[derive(Clone, Copy, Debug, Eq, MallocSizeOf, PartialEq, ToComputedValue)]
-        pub struct T {
-            pub autoflow: AutoFlow,
-            pub dense: bool,
-        }
-    }
-
-    impl ToCss for computed_value::T {
-        fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
-            dest.write_str(match self.autoflow {
-                computed_value::AutoFlow::Column => "column",
-                computed_value::AutoFlow::Row => "row"
-            })?;
-
-            if self.dense { dest.write_str(" dense")?; }
-            Ok(())
-        }
-    }
-
-    #[inline]
-    pub fn get_initial_value() -> computed_value::T {
-        computed_value::T {
-            autoflow: computed_value::AutoFlow::Row,
-            dense: false,
-        }
-    }
-
-    /// [ row | column ] || dense
-    pub fn parse<'i, 't>(_context: &ParserContext, input: &mut Parser<'i, 't>)
-                         -> Result<SpecifiedValue, ParseError<'i>> {
-        use self::computed_value::AutoFlow;
-
-        let mut value = None;
-        let mut dense = false;
-
-        while !input.is_exhausted() {
-            let location = input.current_source_location();
-            let ident = input.expect_ident()?;
-            let success = match_ignore_ascii_case! { &ident,
-                "row" if value.is_none() => {
-                    value = Some(AutoFlow::Row);
-                    true
-                },
-                "column" if value.is_none() => {
-                    value = Some(AutoFlow::Column);
-                    true
-                },
-                "dense" if !dense => {
-                    dense = true;
-                    true
-                },
-                _ => false
-            };
-            if !success {
-                return Err(location.new_custom_error(SelectorParseErrorKind::UnexpectedIdent(ident.clone())));
-            }
-        }
-
-        if value.is_some() || dense {
-            Ok(computed_value::T {
-                autoflow: value.unwrap_or(AutoFlow::Row),
-                dense: dense,
-            })
-        } else {
-            Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError))
-        }
-    }
-
-    #[cfg(feature = "gecko")]
-    impl From<u8> for SpecifiedValue {
-        fn from(bits: u8) -> SpecifiedValue {
-            use gecko_bindings::structs;
-            use self::computed_value::AutoFlow;
-
-            SpecifiedValue {
-                autoflow:
-                    if bits & structs::NS_STYLE_GRID_AUTO_FLOW_ROW as u8 != 0 {
-                        AutoFlow::Row
-                    } else {
-                        AutoFlow::Column
-                    },
-                dense:
-                    bits & structs::NS_STYLE_GRID_AUTO_FLOW_DENSE as u8 != 0,
-            }
-        }
-    }
-
-    #[cfg(feature = "gecko")]
-    impl From<SpecifiedValue> for u8 {
-        fn from(v: SpecifiedValue) -> u8 {
-            use gecko_bindings::structs;
-            use self::computed_value::AutoFlow;
-
-            let mut result: u8 = match v.autoflow {
-                AutoFlow::Row => structs::NS_STYLE_GRID_AUTO_FLOW_ROW as u8,
-                AutoFlow::Column => structs::NS_STYLE_GRID_AUTO_FLOW_COLUMN as u8,
-            };
-
-            if v.dense {
-                result |= structs::NS_STYLE_GRID_AUTO_FLOW_DENSE as u8;
-            }
-            result
-        }
-    }
-</%helpers:longhand>
+${helpers.predefined_type("grid-auto-flow",
+                          "GridAutoFlow",
+                          initial_value="computed::GridAutoFlow::row()",
+                          products="gecko",
+                          animation_value_type="discrete",
+                          gecko_pref="layout.css.grid.enabled",
+                          spec="https://drafts.csswg.org/css-grid/#propdef-grid-auto-flow")}
 
 <%helpers:longhand name="grid-template-areas"
         spec="https://drafts.csswg.org/css-grid/#propdef-grid-template-areas"

components/style/properties/shorthand/position.mako.rs

@@ -470,10 +470,10 @@
                     products="gecko">
     use parser::Parse;
     use properties::longhands::{grid_auto_columns, grid_auto_rows, grid_auto_flow};
-    use properties::longhands::grid_auto_flow::computed_value::{AutoFlow, T as SpecifiedAutoFlow};
     use values::{Either, None_};
     use values::generics::grid::{GridTemplateComponent, TrackListType};
     use values::specified::{GenericGridTemplateComponent, TrackSize};
+    use values::specified::position::{AutoFlow, GridAutoFlow};
 
     pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
                                -> Result<Longhands, ParseError<'i>> {
@@ -485,7 +485,7 @@
         let mut flow = grid_auto_flow::get_initial_value();
 
         fn parse_auto_flow<'i, 't>(input: &mut Parser<'i, 't>, is_row: bool)
-                                   -> Result<SpecifiedAutoFlow, ParseError<'i>> {
+                                   -> Result<GridAutoFlow, ParseError<'i>> {
             let mut auto_flow = None;
             let mut dense = false;
             for _ in 0..2 {
@@ -503,7 +503,7 @@
             }
 
             auto_flow.map(|flow| {
-                SpecifiedAutoFlow {
+                GridAutoFlow {
                     autoflow: flow,
                     dense: dense,
                 }

components/style/values/computed/mod.rs

@@ -54,7 +54,7 @@ pub use self::length::{CalcLengthOrPercentage, Length, LengthOrNone, LengthOrNum
 pub use self::length::{LengthOrPercentageOrAuto, LengthOrPercentageOrNone, MaxLength, MozLength};
 pub use self::length::{CSSPixelLength, NonNegativeLength, NonNegativeLengthOrPercentage};
 pub use self::percentage::Percentage;
-pub use self::position::Position;
+pub use self::position::{Position, GridAutoFlow};
 pub use self::svg::{SVGLength, SVGOpacity, SVGPaint, SVGPaintKind, SVGStrokeDashArray, SVGWidth};
 pub use self::table::XSpan;
 pub use self::text::{InitialLetter, LetterSpacing, LineHeight, TextOverflow, WordSpacing};

components/style/values/computed/position.rs

@@ -11,6 +11,7 @@ use std::fmt;
 use style_traits::ToCss;
 use values::computed::{LengthOrPercentage, Percentage};
 use values::generics::position::Position as GenericPosition;
+pub use values::specified::position::GridAutoFlow;
 
 /// The computed value of a CSS `<position>`
 pub type Position = GenericPosition<HorizontalPosition, VerticalPosition>;

components/style/values/specified/mod.rs

@@ -50,7 +50,7 @@ pub use self::length::{NoCalcLength, ViewportPercentageLength};
 pub use self::length::NonNegativeLengthOrPercentage;
 pub use self::rect::LengthOrNumberRect;
 pub use self::percentage::Percentage;
-pub use self::position::{Position, PositionComponent};
+pub use self::position::{Position, PositionComponent, GridAutoFlow};
 pub use self::svg::{SVGLength, SVGOpacity, SVGPaint, SVGPaintKind, SVGStrokeDashArray, SVGWidth};
 pub use self::table::XSpan;
 pub use self::text::{InitialLetter, LetterSpacing, LineHeight, TextDecorationLine, TextOverflow, WordSpacing};

components/style/values/specified/position.rs

@@ -9,8 +9,9 @@
 
 use cssparser::Parser;
 use parser::{Parse, ParserContext};
+use selectors::parser::SelectorParseErrorKind;
 use std::fmt;
-use style_traits::{ToCss, ParseError};
+use style_traits::{ToCss, StyleParseErrorKind, ParseError};
 use values::computed::{CalcLengthOrPercentage, LengthOrPercentage as ComputedLengthOrPercentage};
 use values::computed::{Context, Percentage, ToComputedValue};
 use values::generics::position::Position as GenericPosition;
@@ -366,3 +367,122 @@ impl ToCss for LegacyPosition {
         self.vertical.to_css(dest)
     }
 }
+
+#[derive(Clone, Copy, Debug, Eq, MallocSizeOf, PartialEq, ToComputedValue, ToCss)]
+/// Auto-placement algorithm Option
+pub enum AutoFlow {
+    /// The auto-placement algorithm places items by filling each row in turn,
+    /// adding new rows as necessary.
+    Row,
+    /// The auto-placement algorithm places items by filling each column in turn,
+    /// adding new columns as necessary.
+    Column,
+}
+
+#[derive(Clone, Copy, Debug, Eq, MallocSizeOf, PartialEq, ToComputedValue)]
+/// Controls how the auto-placement algorithm works
+/// specifying exactly how auto-placed items get flowed into the grid
+pub struct GridAutoFlow {
+    /// Specifiy how auto-placement algorithm fills each `row` or `column` in turn
+    pub autoflow: AutoFlow,
+    /// Specify use `dense` packing algorithm or not
+    pub dense: bool,
+}
+
+impl GridAutoFlow {
+    #[inline]
+    /// Get default `grid-auto-flow` as `row`
+    pub fn row() -> GridAutoFlow {
+        GridAutoFlow {
+            autoflow: AutoFlow::Row,
+            dense: false,
+        }
+    }
+}
+
+impl ToCss for GridAutoFlow {
+    fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
+        self.autoflow.to_css(dest)?;
+
+        if self.dense { dest.write_str(" dense")?; }
+        Ok(())
+    }
+}
+
+impl Parse for GridAutoFlow {
+    /// [ row | column ] || dense
+    fn parse<'i, 't>(
+        _context: &ParserContext,
+        input: &mut Parser<'i, 't>
+    ) -> Result<GridAutoFlow, ParseError<'i>> {
+        let mut value = None;
+        let mut dense = false;
+
+        while !input.is_exhausted() {
+            let location = input.current_source_location();
+            let ident = input.expect_ident()?;
+            let success = match_ignore_ascii_case! { &ident,
+                "row" if value.is_none() => {
+                    value = Some(AutoFlow::Row);
+                    true
+                },
+                "column" if value.is_none() => {
+                    value = Some(AutoFlow::Column);
+                    true
+                },
+                "dense" if !dense => {
+                    dense = true;
+                    true
+                },
+                _ => false
+            };
+            if !success {
+                return Err(location.new_custom_error(SelectorParseErrorKind::UnexpectedIdent(ident.clone())));
+            }
+        }
+
+        if value.is_some() || dense {
+            Ok(GridAutoFlow {
+                autoflow: value.unwrap_or(AutoFlow::Row),
+                dense: dense,
+            })
+        } else {
+            Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError))
+        }
+    }
+}
+
+#[cfg(feature = "gecko")]
+impl From<u8> for GridAutoFlow {
+    fn from(bits: u8) -> GridAutoFlow {
+        use gecko_bindings::structs;
+
+        GridAutoFlow {
+            autoflow:
+                if bits & structs::NS_STYLE_GRID_AUTO_FLOW_ROW as u8 != 0 {
+                    AutoFlow::Row
+                } else {
+                    AutoFlow::Column
+                },
+            dense:
+                bits & structs::NS_STYLE_GRID_AUTO_FLOW_DENSE as u8 != 0,
+        }
+    }
+}
+
+#[cfg(feature = "gecko")]
+impl From<GridAutoFlow> for u8 {
+    fn from(v: GridAutoFlow) -> u8 {
+        use gecko_bindings::structs;
+
+        let mut result: u8 = match v.autoflow {
+            AutoFlow::Row => structs::NS_STYLE_GRID_AUTO_FLOW_ROW as u8,
+            AutoFlow::Column => structs::NS_STYLE_GRID_AUTO_FLOW_COLUMN as u8,
+        };
+
+        if v.dense {
+            result |= structs::NS_STYLE_GRID_AUTO_FLOW_DENSE as u8;
+        }
+        result
+    }
+}