Implement Calc for LengthOrPercentage

components/layout/block.rs

@@ -329,9 +329,8 @@ impl CandidateBSizeIterator {
             (LengthOrPercentageOrAuto::Length(length), _) => MaybeAuto::Specified(length),
         };
         let max_block_size = match (fragment.style.max_block_size(), block_container_block_size) {
-            (LengthOrPercentageOrNone::Percentage(percent), Some(block_container_block_size)) => {
-                Some(block_container_block_size.scale_by(percent))
-            }
+            (LengthOrPercentageOrNone::Percentage(percent), Some(block_container_block_size)) =>
+                Some(block_container_block_size.scale_by(percent)),
             (LengthOrPercentageOrNone::Percentage(_), None) |
             (LengthOrPercentageOrNone::None, _) => None,
             (LengthOrPercentageOrNone::Length(length), _) => Some(length),
@@ -340,6 +339,10 @@ impl CandidateBSizeIterator {
             (LengthOrPercentage::Percentage(percent), Some(block_container_block_size)) => {
                 block_container_block_size.scale_by(percent)
             }
+            (LengthOrPercentage::Calc(calc), Some(block_container_block_size)) => {
+                calc.length() + block_container_block_size.scale_by(calc.percentage())
+            }
+            (LengthOrPercentage::Calc(calc), None) => calc.length(),
             (LengthOrPercentage::Percentage(_), None) => Au(0),
             (LengthOrPercentage::Length(length), _) => length,
         };

components/layout/display_list_builder.rs

@@ -1945,6 +1945,8 @@ fn position_to_offset(position: LengthOrPercentage, Au(total_length): Au) -> f32
             fmin(1.0, (length as f32) / (total_length as f32))
         }
         LengthOrPercentage::Percentage(percentage) => percentage as f32,
+        LengthOrPercentage::Calc(calc) =>
+            fmin(1.0, calc.percentage() + (calc.length().0 as f32) / (total_length as f32)),
     }
 }
 

components/layout/inline.rs

@@ -987,7 +987,12 @@ impl InlineFlow {
                     let percent_offset = line_height.scale_by(p);
                     offset_from_baseline = offset_from_baseline - percent_offset
                 }
-            }
+                vertical_align::T::Calc(calc) => {
+                    let line_height = fragment.calculate_line_height(layout_context);
+                    let percent_offset = line_height.scale_by(calc.percentage());
+                    offset_from_baseline = offset_from_baseline - percent_offset - calc.length()
+                }
+             }
         }
         (offset_from_baseline - ascent, largest_size_updated)
     }

components/layout/model.rs

@@ -416,7 +416,9 @@ pub fn specified_or_none(length: LengthOrPercentageOrNone, containing_length: Au
 pub fn specified(length: LengthOrPercentage, containing_length: Au) -> Au {
     match length {
         LengthOrPercentage::Length(length) => length,
-        LengthOrPercentage::Percentage(p) => containing_length.scale_by(p)
+        LengthOrPercentage::Percentage(p) => containing_length.scale_by(p),
+        LengthOrPercentage::Calc(calc) =>
+            containing_length.scale_by(calc.percentage()) + calc.length(),
     }
 }
 

components/style/properties.mako.rs

@@ -705,7 +705,7 @@ pub mod longhands {
         pub mod computed_value {
             use std::fmt;
             use util::geometry::Au;
-            use values::CSSFloat;
+            use values::{CSSFloat, computed};
             #[allow(non_camel_case_types)]
             #[derive(PartialEq, Copy, Clone, HeapSizeOf)]
             pub enum T {
@@ -714,6 +714,7 @@ pub mod longhands {
                 % endfor
                 Length(Au),
                 Percentage(CSSFloat),
+                Calc(computed::Calc),
             }
             impl fmt::Debug for T {
                 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
@@ -723,6 +724,8 @@ pub mod longhands {
                         % endfor
                         &T::Length(length) => write!(f, "{:?}", length),
                         &T::Percentage(number) => write!(f, "{}%", number),
+                        // XXX HACK WRONG
+                        &T::Calc(calc) => write!(f, "{}%", 10.),
                     }
                 }
             }
@@ -734,6 +737,7 @@ pub mod longhands {
                         % endfor
                         T::Length(value) => value.to_css(dest),
                         T::Percentage(percentage) => write!(dest, "{}%", percentage * 100.),
+                        T::Calc(calc) => calc.to_css(dest),
                     }
                 }
             }
@@ -754,12 +758,12 @@ pub mod longhands {
                     % endfor
                     SpecifiedValue::LengthOrPercentage(value) => {
                         match value.to_computed_value(context) {
-                            computed::LengthOrPercentage::Length(value) => {
-                                computed_value::T::Length(value)
-                            }
-                            computed::LengthOrPercentage::Percentage(value) => {
-                                computed_value::T::Percentage(value)
-                            }
+                            computed::LengthOrPercentage::Length(value) =>
+                                computed_value::T::Length(value),
+                            computed::LengthOrPercentage::Percentage(value) =>
+                                computed_value::T::Percentage(value),
+                            computed::LengthOrPercentage::Calc(value) =>
+                                computed_value::T::Calc(value),
                         }
                     }
                 }
@@ -1858,7 +1862,10 @@ pub mod longhands {
             .map(|value| match value {
                 specified::LengthOrPercentage::Length(value) => value,
                 specified::LengthOrPercentage::Percentage(value) =>
-                    specified::Length::FontRelative(specified::FontRelativeLength::Em(value))
+                    specified::Length::FontRelative(specified::FontRelativeLength::Em(value)),
+                // XXX WRONG HACK
+                specified::LengthOrPercentage::Calc(calc) =>
+                    specified::Length::FontRelative(specified::FontRelativeLength::Em(20.)),
             })
             .or_else(|()| {
                 match_ignore_ascii_case! { try!(input.expect_ident()),

components/style/values.rs

@@ -353,11 +353,93 @@ pub mod specified {
         }
     }
 
+    #[derive(Clone, PartialEq, Copy, Debug, HeapSizeOf)]
+    pub struct Calc {
+        pub absolute: Option<Au>,
+        pub font_relative: Option<FontRelativeLength>,
+        pub viewport_percentage: Option<ViewportPercentageLength>,
+        pub percentage: Option<CSSFloat>,
+    }
+    impl Calc {
+        pub fn parse_component(&mut self, input: &mut Parser) -> Result<(), ()> {
+             match try!(input.next()) {
+                Token::Dimension(ref value, ref unit) => {
+                    let value = value.value;
+                    match_ignore_ascii_case! { unit,
+                        "px" => self.absolute =
+                            Some(self.absolute.unwrap_or(Au(0)) + Au((value * AU_PER_PX) as i32)),
+                        "in" => self.absolute =
+                            Some(self.absolute.unwrap_or(Au(0)) + Au((value * AU_PER_IN) as i32)),
+                        "cm" => self.absolute =
+                            Some(self.absolute.unwrap_or(Au(0)) + Au((value * AU_PER_CM) as i32)),
+                        "mm" => self.absolute =
+                            Some(self.absolute.unwrap_or(Au(0)) + Au((value * AU_PER_MM) as i32)),
+                        "pt" => self.absolute =
+                            Some(self.absolute.unwrap_or(Au(0)) + Au((value * AU_PER_PT) as i32)),
+                        "pc" => self.absolute =
+                            Some(self.absolute.unwrap_or(Au(0)) + Au((value * AU_PER_PC) as i32))
+                        // font-relative
+                        /*"em" => Ok(Length::FontRelative(FontRelativeLength::Em(value))),
+                        "ex" => Ok(Length::FontRelative(FontRelativeLength::Ex(value))),
+                        "rem" => Ok(Length::FontRelative(FontRelativeLength::Rem(value))),
+                        // viewport percentages
+                        "vw" => Ok(Length::ViewportPercentage(ViewportPercentageLength::Vw(value))),
+                        "vh" => Ok(Length::ViewportPercentage(ViewportPercentageLength::Vh(value))),
+                        "vmin" => Ok(Length::ViewportPercentage(ViewportPercentageLength::Vmin(value))),
+                        "vmax" => Ok(Length::ViewportPercentage(ViewportPercentageLength::Vmax(value)))*/
+                        // Handle em, ex, rem, vw, vh, vmin, vmax
+                        _ => return Err(())
+                    }
+                },
+                Token::Percentage(ref value) =>
+                    self.percentage = Some(self.percentage.unwrap_or(0.) + value.unit_value),
+                Token::Number(ref value) if value.value == 0. =>
+                    self.absolute = self.absolute.or(Some(Au(0))),
+                _ => return Err(())
+            };
+            Ok(())
+        }
+
+        pub fn parse(input: &mut Parser) -> Result<Calc, ()> {
+            let mut calc = Calc {
+                absolute: None,
+                font_relative: None,
+                viewport_percentage: None,
+                percentage: None,
+            };
+
+            try!(calc.parse_component(input));
+            let operator = try!(input.next());
+            match operator {
+                Token::Delim('+') => (),
+                _ => return Err(())
+            };
+
+            try!(calc.parse_component(input));
+            Ok(calc)
+        }
+    }
+
+    impl ToCss for Calc {
+        fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
+            // XXX WRONG HACK
+            try!(write!(dest, "calc("));
+            if let Some(absolute) = self.absolute {
+                try!(write!(dest, "{}px", Au::to_px(absolute)));
+            }
+            if let Some(FontRelativeLength::Em(font_relative)) = self.font_relative {
+                try!(write!(dest, "{}em", font_relative));
+            }
+
+            write!(dest, ")")
+         }
+    }
 
     #[derive(Clone, PartialEq, Copy, Debug, HeapSizeOf)]
     pub enum LengthOrPercentage {
         Length(Length),
         Percentage(CSSFloat),  // [0 .. 100%] maps to [0.0 .. 1.0]
+        Calc(Calc),
     }
 
     impl ToCss for LengthOrPercentage {
@@ -366,6 +448,7 @@ pub mod specified {
                 &LengthOrPercentage::Length(length) => length.to_css(dest),
                 &LengthOrPercentage::Percentage(percentage)
                 => write!(dest, "{}%", percentage * 100.),
+                &LengthOrPercentage::Calc(calc) => calc.to_css(dest),
             }
         }
     }
@@ -384,6 +467,10 @@ pub mod specified {
                     Ok(LengthOrPercentage::Percentage(value.unit_value)),
                 Token::Number(ref value) if value.value == 0. =>
                     Ok(LengthOrPercentage::Length(Length::Absolute(Au(0)))),
+                Token::Function(ref name) if name.eq_ignore_ascii_case("calc") => {
+                    let calc = try!(input.parse_nested_block(Calc::parse));
+                    Ok(LengthOrPercentage::Calc(calc))
+                },
                 _ => Err(())
             }
         }
@@ -938,10 +1025,50 @@ pub mod computed {
         }
     }
 
+    #[derive(Clone, PartialEq, Copy, Debug, HeapSizeOf)]
+    pub struct Calc {
+        length: Option<Au>,
+        percentage: Option<CSSFloat>,
+    }
+
+    impl Calc {
+        pub fn length(&self) -> Au {
+            self.length.unwrap_or(Au(0))
+        }
+
+        pub fn percentage(&self) -> CSSFloat {
+            self.percentage.unwrap_or(0.)
+        }
+    }
+
+    impl ::cssparser::ToCss for Calc {
+        fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
+            match (self.length, self.percentage) {
+                (None, Some(p)) => write!(dest, "{}%", p),
+                (Some(l), None) => write!(dest, "{}px", Au::to_px(l)),
+                (Some(l), Some(p)) => write!(dest, "calc({}px + {}%)", Au::to_px(l), p * 100.),
+                _ => unreachable!()
+            }
+        }
+    }
+
+    impl ToComputedValue for specified::Calc {
+        type ComputedValue = Calc;
+
+        fn to_computed_value(&self, context: &Context) -> Calc {
+            let length = self.absolute;
+            let percentage = self.percentage;
+
+            Calc { length: length, percentage: percentage }
+        }
+    }
+
+
     #[derive(PartialEq, Clone, Copy, HeapSizeOf)]
     pub enum LengthOrPercentage {
         Length(Au),
         Percentage(CSSFloat),
+        Calc(Calc),
     }
 
     impl LengthOrPercentage {
@@ -955,6 +1082,8 @@ pub mod computed {
             match self {
                 &LengthOrPercentage::Length(length) => write!(f, "{:?}", length),
                 &LengthOrPercentage::Percentage(percentage) => write!(f, "{}%", percentage * 100.),
+                // XXX HACK WRONG
+                &LengthOrPercentage::Calc(calc) => write!(f, "{}%", 100.),
             }
         }
     }
@@ -970,6 +1099,9 @@ pub mod computed {
                 specified::LengthOrPercentage::Percentage(value) => {
                     LengthOrPercentage::Percentage(value)
                 }
+                specified::LengthOrPercentage::Calc(calc) => {
+                    LengthOrPercentage::Calc(calc.to_computed_value(context))
+                }
             }
         }
     }
@@ -980,6 +1112,7 @@ pub mod computed {
                 &LengthOrPercentage::Length(length) => length.to_css(dest),
                 &LengthOrPercentage::Percentage(percentage)
                 => write!(dest, "{}%", percentage * 100.),
+                &LengthOrPercentage::Calc(calc) => calc.to_css(dest),
             }
         }
     }