Auto merge of #16829 - hiikezoe:disallow-negative-duration, r=emilio

Disallow negative duration for animation and transition

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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 #15343

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- [X] There are tests for these changes written by @simon-whitehead . Thank you!

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

@@ -444,7 +444,7 @@ ${helpers.single_keyword("overflow-x", "visible hidden scroll auto",
     }
 
     pub fn parse(context: &ParserContext, input: &mut Parser) -> Result<SpecifiedValue,()> {
-        Time::parse(context, input)
+        Time::parse_non_negative(context, input)
     }
 </%helpers:vector_longhand>
 
@@ -824,7 +824,11 @@ ${helpers.single_keyword("overflow-x", "visible hidden scroll auto",
     pub use properties::longhands::transition_duration::single_value::SpecifiedValue;
     pub use properties::longhands::transition_duration::single_value::computed_value;
     pub use properties::longhands::transition_duration::single_value::{get_initial_value, get_initial_specified_value};
-    pub use properties::longhands::transition_duration::single_value::parse;
+
+    pub fn parse(context: &ParserContext, input: &mut Parser) -> Result<SpecifiedValue, ()> {
+        use values::specified::Time;
+        Time::parse(context, input)
+    }
 </%helpers:vector_longhand>
 
 <%helpers:vector_longhand name="animation-name"
@@ -1031,10 +1035,10 @@ ${helpers.single_keyword("animation-fill-mode",
                           extra_prefixes="moz webkit",
                           spec="https://drafts.csswg.org/css-animations/#propdef-animation-delay",
                           allowed_in_keyframe_block="False">
-    pub use properties::longhands::transition_duration::single_value::computed_value;
-    pub use properties::longhands::transition_duration::single_value::get_initial_specified_value;
-    pub use properties::longhands::transition_duration::single_value::{get_initial_value, parse};
-    pub use properties::longhands::transition_duration::single_value::SpecifiedValue;
+    pub use properties::longhands::transition_delay::single_value::computed_value;
+    pub use properties::longhands::transition_delay::single_value::get_initial_specified_value;
+    pub use properties::longhands::transition_delay::single_value::{get_initial_value, parse};
+    pub use properties::longhands::transition_delay::single_value::SpecifiedValue;
 </%helpers:vector_longhand>
 
 <%helpers:longhand products="gecko" name="scroll-snap-points-y" animation_value_type="none"

components/style/values/specified/mod.rs

@@ -539,6 +539,28 @@ impl Time {
             was_calc: true,
         }
     }
+
+    fn parse_with_clamping_mode(context: &ParserContext,
+                                input: &mut Parser,
+                                clamping_mode: AllowedNumericType) -> Result<Self, ()> {
+        match input.next() {
+            Ok(Token::Dimension(ref value, ref unit)) if clamping_mode.is_ok(value.value) => {
+                Time::parse_dimension(value.value, &unit, /* from_calc = */ false)
+            }
+            Ok(Token::Function(ref name)) if name.eq_ignore_ascii_case("calc") => {
+                match input.parse_nested_block(|i| CalcNode::parse_time(context, i)) {
+                    Ok(time) if clamping_mode.is_ok(time.seconds) => Ok(time),
+                    _ => Err(()),
+                }
+            }
+            _ => Err(())
+        }
+    }
+
+    /// Parse <time> that values are non-negative.
+    pub fn parse_non_negative(context: &ParserContext, input: &mut Parser) -> Result<Self, ()> {
+        Self::parse_with_clamping_mode(context, input, AllowedNumericType::NonNegative)
+    }
 }
 
 impl ToComputedValue for Time {
@@ -558,15 +580,7 @@ impl ToComputedValue for Time {
 
 impl Parse for Time {
     fn parse(context: &ParserContext, input: &mut Parser) -> Result<Self, ()> {
-        match input.next() {
-            Ok(Token::Dimension(ref value, ref unit)) => {
-                Time::parse_dimension(value.value, &unit, /* from_calc = */ false)
-            }
-            Ok(Token::Function(ref name)) if name.eq_ignore_ascii_case("calc") => {
-                input.parse_nested_block(|i| CalcNode::parse_time(context, i))
-            }
-            _ => Err(())
-        }
+        Self::parse_with_clamping_mode(context, input, AllowedNumericType::All)
     }
 }
 

tests/unit/style/parsing/mod.rs

@@ -105,6 +105,7 @@ mod selectors;
 mod supports;
 mod text;
 mod text_overflow;
+mod transition_duration;
 mod transition_property;
 mod transition_timing_function;
 mod ui;

tests/unit/style/parsing/transition_duration.rs

@@ -0,0 +1,17 @@
+/* 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 parsing::parse;
+use style::properties::longhands::transition_duration;
+
+#[test]
+fn test_positive_transition_duration() {
+    assert!(parse(transition_duration::parse, "5s").is_ok());
+    assert!(parse(transition_duration::parse, "0s").is_ok());
+}
+
+#[test]
+fn test_negative_transition_duration() {
+    assert!(parse(transition_duration::parse, "-5s").is_err());
+}

tests/wpt/metadata-css/css-transitions-1_dev/html/transition-duration-001.htm.ini

@@ -1,8 +0,0 @@
-[transition-duration-001.htm]
-  type: testharness
-  [parse '-5s']
-    expected: FAIL
-
-  [parse '-500ms']
-    expected: FAIL
-

tests/wpt/metadata-css/css-values-3_dev/html/transition-duration-001.htm.ini

@@ -1,8 +0,0 @@
-[transition-duration-001.htm]
-  type: testharness
-  [parse '-5s']
-    expected: FAIL
-
-  [parse '-500ms']
-    expected: FAIL
-