Fix InsertRule to use the right CssRuleTypes (#32125)

`CSSRule::Type()` returns an u16 for CSSOM. `InsertRule()` was
incorrectly using this to create a `CssRuleTypes`.

Instead of `CssRuleTypes::from_bits(rule_type)`, it should be something
like `CssRuleTypes::from_bits(1 << rule_type)`.

However, that would only work when `Type()` provides an actual value,
which per https://drafts.csswg.org/cssom/#dom-cssrule-type only happens
for old rule types. New rule types just return 0.

Therefore, this patch changes the signature of `SpecificCSSRule::ty()`
to return the actual `CssRuleType`, and then `CSSRule::Type()` can zero
it out when necessary.

The fix is only relevant for CSS Nesting, which is currently disabled on
Servo, so no test is necessary.

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


---
<!-- 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 do not require tests because the fix is only
relevant for CSS Nesting, which is currently disabled

<!-- Also, please make sure that "Allow edits from maintainers" checkbox
is checked, so that we can help you if you get stuck somewhere along the
way.-->

<!-- Pull requests that do not address these steps are welcome, but they
will require additional verification as part of the review process. -->

12 files changed, 42 insertions, 41 deletions

diff --git a/components/script/dom/cssfontfacerule.rs b/components/script/dom/cssfontfacerule.rs
index 125d7a82fbb..67027da294a 100644
--- a/components/script/dom/cssfontfacerule.rs
+++ b/components/script/dom/cssfontfacerule.rs
@@ -5,7 +5,7 @@
 use dom_struct::dom_struct;
 use servo_arc::Arc;
 use style::shared_lock::{Locked, ToCssWithGuard};
-use style::stylesheets::FontFaceRule;
+use style::stylesheets::{CssRuleType, FontFaceRule};
 
 use crate::dom::bindings::reflector::reflect_dom_object;
 use crate::dom::bindings::root::DomRoot;
@@ -50,9 +50,8 @@ impl CSSFontFaceRule {
 }
 
 impl SpecificCSSRule for CSSFontFaceRule {
-    fn ty(&self) -> u16 {
-        use crate::dom::bindings::codegen::Bindings::CSSRuleBinding::CSSRuleConstants;
-        CSSRuleConstants::FONT_FACE_RULE
+    fn ty(&self) -> CssRuleType {
+        CssRuleType::FontFace
     }
 
     fn get_css(&self) -> DOMString {
diff --git a/components/script/dom/cssgroupingrule.rs b/components/script/dom/cssgroupingrule.rs
index a84208f7c45..eb542c6205c 100644
--- a/components/script/dom/cssgroupingrule.rs
+++ b/components/script/dom/cssgroupingrule.rs
@@ -8,7 +8,6 @@ use style::shared_lock::{Locked, SharedRwLock};
 use style::stylesheets::{CssRuleTypes, CssRules as StyleCssRules};
 
 use crate::dom::bindings::codegen::Bindings::CSSGroupingRuleBinding::CSSGroupingRuleMethods;
-use crate::dom::bindings::codegen::Bindings::CSSRuleBinding::CSSRule_Binding::CSSRuleMethods;
 use crate::dom::bindings::error::{ErrorResult, Fallible};
 use crate::dom::bindings::inheritance::Castable;
 use crate::dom::bindings::reflector::DomObject;
@@ -69,7 +68,8 @@ impl CSSGroupingRuleMethods for CSSGroupingRule {
     // https://drafts.csswg.org/cssom/#dom-cssgroupingrule-insertrule
     fn InsertRule(&self, rule: DOMString, index: u32) -> Fallible<u32> {
         // TODO: this should accumulate the rule types of all ancestors.
-        let containing_rule_types = CssRuleTypes::from_bits(self.cssrule.Type().into());
+        let rule_type = self.cssrule.as_specific().ty();
+        let containing_rule_types = CssRuleTypes::from(rule_type);
         self.rulelist()
             .insert_rule(&rule, index, containing_rule_types)
     }
diff --git a/components/script/dom/cssimportrule.rs b/components/script/dom/cssimportrule.rs
index 2a9bdf44b9c..d75ec291460 100644
--- a/components/script/dom/cssimportrule.rs
+++ b/components/script/dom/cssimportrule.rs
@@ -6,7 +6,7 @@ use dom_struct::dom_struct;
 use servo_arc::Arc;
 use style::shared_lock::{Locked, ToCssWithGuard};
 use style::stylesheets::import_rule::ImportLayer;
-use style::stylesheets::ImportRule;
+use style::stylesheets::{CssRuleType, ImportRule};
 use style_traits::ToCss;
 
 use crate::dom::bindings::codegen::Bindings::CSSImportRuleBinding::CSSImportRuleMethods;
@@ -50,9 +50,8 @@ impl CSSImportRule {
 }
 
 impl SpecificCSSRule for CSSImportRule {
-    fn ty(&self) -> u16 {
-        use crate::dom::bindings::codegen::Bindings::CSSRuleBinding::CSSRuleConstants;
-        CSSRuleConstants::IMPORT_RULE
+    fn ty(&self) -> CssRuleType {
+        CssRuleType::Import
     }
 
     fn get_css(&self) -> DOMString {
diff --git a/components/script/dom/csskeyframerule.rs b/components/script/dom/csskeyframerule.rs
index 4bbf7b026f0..f53f68956fb 100644
--- a/components/script/dom/csskeyframerule.rs
+++ b/components/script/dom/csskeyframerule.rs
@@ -6,6 +6,7 @@ use dom_struct::dom_struct;
 use servo_arc::Arc;
 use style::shared_lock::{Locked, ToCssWithGuard};
 use style::stylesheets::keyframes_rule::Keyframe;
+use style::stylesheets::CssRuleType;
 
 use crate::dom::bindings::codegen::Bindings::CSSKeyframeRuleBinding::CSSKeyframeRuleMethods;
 use crate::dom::bindings::inheritance::Castable;
@@ -73,9 +74,8 @@ impl CSSKeyframeRuleMethods for CSSKeyframeRule {
 }
 
 impl SpecificCSSRule for CSSKeyframeRule {
-    fn ty(&self) -> u16 {
-        use crate::dom::bindings::codegen::Bindings::CSSRuleBinding::CSSRuleConstants;
-        CSSRuleConstants::KEYFRAME_RULE
+    fn ty(&self) -> CssRuleType {
+        CssRuleType::Keyframe
     }
 
     fn get_css(&self) -> DOMString {
diff --git a/components/script/dom/csskeyframesrule.rs b/components/script/dom/csskeyframesrule.rs
index 62fb03ec925..272e7086a41 100644
--- a/components/script/dom/csskeyframesrule.rs
+++ b/components/script/dom/csskeyframesrule.rs
@@ -7,6 +7,7 @@ use dom_struct::dom_struct;
 use servo_arc::Arc;
 use style::shared_lock::{Locked, ToCssWithGuard};
 use style::stylesheets::keyframes_rule::{Keyframe, KeyframeSelector, KeyframesRule};
+use style::stylesheets::CssRuleType;
 use style::values::KeyframesName;
 
 use crate::dom::bindings::codegen::Bindings::CSSKeyframesRuleBinding::CSSKeyframesRuleMethods;
@@ -145,9 +146,8 @@ impl CSSKeyframesRuleMethods for CSSKeyframesRule {
 }
 
 impl SpecificCSSRule for CSSKeyframesRule {
-    fn ty(&self) -> u16 {
-        use crate::dom::bindings::codegen::Bindings::CSSRuleBinding::CSSRuleConstants;
-        CSSRuleConstants::KEYFRAMES_RULE
+    fn ty(&self) -> CssRuleType {
+        CssRuleType::Keyframes
     }
 
     fn get_css(&self) -> DOMString {
diff --git a/components/script/dom/csslayerblockrule.rs b/components/script/dom/csslayerblockrule.rs
index 08779e62f98..21db85c2f6d 100644
--- a/components/script/dom/csslayerblockrule.rs
+++ b/components/script/dom/csslayerblockrule.rs
@@ -5,7 +5,7 @@
 use dom_struct::dom_struct;
 use servo_arc::Arc;
 use style::shared_lock::ToCssWithGuard;
-use style::stylesheets::LayerBlockRule;
+use style::stylesheets::{CssRuleType, LayerBlockRule};
 use style_traits::ToCss;
 
 use crate::dom::bindings::codegen::Bindings::CSSLayerBlockRuleBinding::CSSLayerBlockRuleMethods;
@@ -56,8 +56,8 @@ impl CSSLayerBlockRule {
 }
 
 impl SpecificCSSRule for CSSLayerBlockRule {
-    fn ty(&self) -> u16 {
-        0
+    fn ty(&self) -> CssRuleType {
+        CssRuleType::LayerBlock
     }
 
     fn get_css(&self) -> DOMString {
diff --git a/components/script/dom/csslayerstatementrule.rs b/components/script/dom/csslayerstatementrule.rs
index f2dbfeca0fd..9a4aa5a0dc9 100644
--- a/components/script/dom/csslayerstatementrule.rs
+++ b/components/script/dom/csslayerstatementrule.rs
@@ -6,7 +6,7 @@ use dom_struct::dom_struct;
 use js::jsval::JSVal;
 use servo_arc::Arc;
 use style::shared_lock::ToCssWithGuard;
-use style::stylesheets::LayerStatementRule;
+use style::stylesheets::{CssRuleType, LayerStatementRule};
 use style_traits::ToCss;
 
 use crate::dom::bindings::codegen::Bindings::CSSLayerStatementRuleBinding::CSSLayerStatementRuleMethods;
@@ -55,8 +55,8 @@ impl CSSLayerStatementRule {
 }
 
 impl SpecificCSSRule for CSSLayerStatementRule {
-    fn ty(&self) -> u16 {
-        0
+    fn ty(&self) -> CssRuleType {
+        CssRuleType::LayerStatement
     }
 
     fn get_css(&self) -> DOMString {
diff --git a/components/script/dom/cssmediarule.rs b/components/script/dom/cssmediarule.rs
index f321cd64bf4..3ecf63b1c22 100644
--- a/components/script/dom/cssmediarule.rs
+++ b/components/script/dom/cssmediarule.rs
@@ -5,7 +5,7 @@
 use dom_struct::dom_struct;
 use servo_arc::Arc;
 use style::shared_lock::ToCssWithGuard;
-use style::stylesheets::MediaRule;
+use style::stylesheets::{CssRuleType, MediaRule};
 use style_traits::ToCss;
 
 use crate::dom::bindings::codegen::Bindings::CSSMediaRuleBinding::CSSMediaRuleMethods;
@@ -68,9 +68,8 @@ impl CSSMediaRule {
 }
 
 impl SpecificCSSRule for CSSMediaRule {
-    fn ty(&self) -> u16 {
-        use crate::dom::bindings::codegen::Bindings::CSSRuleBinding::CSSRuleConstants;
-        CSSRuleConstants::MEDIA_RULE
+    fn ty(&self) -> CssRuleType {
+        CssRuleType::Media
     }
 
     fn get_css(&self) -> DOMString {
diff --git a/components/script/dom/cssnamespacerule.rs b/components/script/dom/cssnamespacerule.rs
index 0c51b43f387..30395f0158b 100644
--- a/components/script/dom/cssnamespacerule.rs
+++ b/components/script/dom/cssnamespacerule.rs
@@ -5,7 +5,7 @@
 use dom_struct::dom_struct;
 use servo_arc::Arc;
 use style::shared_lock::ToCssWithGuard;
-use style::stylesheets::NamespaceRule;
+use style::stylesheets::{CssRuleType, NamespaceRule};
 
 use crate::dom::bindings::codegen::Bindings::CSSNamespaceRuleBinding::CSSNamespaceRuleMethods;
 use crate::dom::bindings::reflector::reflect_dom_object;
@@ -67,9 +67,8 @@ impl CSSNamespaceRuleMethods for CSSNamespaceRule {
 }
 
 impl SpecificCSSRule for CSSNamespaceRule {
-    fn ty(&self) -> u16 {
-        use crate::dom::bindings::codegen::Bindings::CSSRuleBinding::CSSRuleConstants;
-        CSSRuleConstants::NAMESPACE_RULE
+    fn ty(&self) -> CssRuleType {
+        CssRuleType::Namespace
     }
 
     fn get_css(&self) -> DOMString {
diff --git a/components/script/dom/cssrule.rs b/components/script/dom/cssrule.rs
index c56f299c16f..4c7c0b7bd0a 100644
--- a/components/script/dom/cssrule.rs
+++ b/components/script/dom/cssrule.rs
@@ -6,7 +6,7 @@ use std::cell::Cell;
 
 use dom_struct::dom_struct;
 use style::shared_lock::SharedRwLock;
-use style::stylesheets::CssRule as StyleCssRule;
+use style::stylesheets::{CssRule as StyleCssRule, CssRuleType};
 
 use crate::dom::bindings::codegen::Bindings::CSSRuleBinding::CSSRuleMethods;
 use crate::dom::bindings::inheritance::Castable;
@@ -147,7 +147,14 @@ impl CSSRule {
 impl CSSRuleMethods for CSSRule {
     // https://drafts.csswg.org/cssom/#dom-cssrule-type
     fn Type(&self) -> u16 {
-        self.as_specific().ty()
+        let rule_type = self.as_specific().ty() as u16;
+        // Per https://drafts.csswg.org/cssom/#dom-cssrule-type for constants > 15
+        // we return 0.
+        if rule_type > 15 {
+            0
+        } else {
+            rule_type
+        }
     }
 
     // https://drafts.csswg.org/cssom/#dom-cssrule-parentstylesheet
@@ -171,7 +178,7 @@ impl CSSRuleMethods for CSSRule {
 }
 
 pub trait SpecificCSSRule {
-    fn ty(&self) -> u16;
+    fn ty(&self) -> CssRuleType;
     fn get_css(&self) -> DOMString;
     /// Remove parentStylesheet from all transitive children
     fn deparent_children(&self) {
diff --git a/components/script/dom/cssstylerule.rs b/components/script/dom/cssstylerule.rs
index fe9fecfb4b1..f2e6c279d0e 100644
--- a/components/script/dom/cssstylerule.rs
+++ b/components/script/dom/cssstylerule.rs
@@ -10,7 +10,7 @@ use selectors::parser::{ParseRelative, SelectorList};
 use servo_arc::Arc;
 use style::selector_parser::SelectorParser;
 use style::shared_lock::{Locked, ToCssWithGuard};
-use style::stylesheets::{Origin, StyleRule};
+use style::stylesheets::{CssRuleType, Origin, StyleRule};
 
 use crate::dom::bindings::codegen::Bindings::CSSStyleRuleBinding::CSSStyleRuleMethods;
 use crate::dom::bindings::inheritance::Castable;
@@ -58,9 +58,8 @@ impl CSSStyleRule {
 }
 
 impl SpecificCSSRule for CSSStyleRule {
-    fn ty(&self) -> u16 {
-        use crate::dom::bindings::codegen::Bindings::CSSRuleBinding::CSSRuleConstants;
-        CSSRuleConstants::STYLE_RULE
+    fn ty(&self) -> CssRuleType {
+        CssRuleType::Style
     }
 
     fn get_css(&self) -> DOMString {
diff --git a/components/script/dom/csssupportsrule.rs b/components/script/dom/csssupportsrule.rs
index 6341bc51a44..18ec34aac0e 100644
--- a/components/script/dom/csssupportsrule.rs
+++ b/components/script/dom/csssupportsrule.rs
@@ -5,7 +5,7 @@
 use dom_struct::dom_struct;
 use servo_arc::Arc;
 use style::shared_lock::ToCssWithGuard;
-use style::stylesheets::SupportsRule;
+use style::stylesheets::{CssRuleType, SupportsRule};
 use style_traits::ToCss;
 
 use crate::dom::bindings::reflector::reflect_dom_object;
@@ -58,9 +58,8 @@ impl CSSSupportsRule {
 }
 
 impl SpecificCSSRule for CSSSupportsRule {
-    fn ty(&self) -> u16 {
-        use crate::dom::bindings::codegen::Bindings::CSSRuleBinding::CSSRuleConstants;
-        CSSRuleConstants::SUPPORTS_RULE
+    fn ty(&self) -> CssRuleType {
+        CssRuleType::Supports
     }
 
     fn get_css(&self) -> DOMString {