Auto merge of #14038 - upsuper:bug1294299, r=heycam

Add Element.style support for stylo

<!-- Please describe your changes on the following line: -->
This is the Servo side change of [bug 1294299](https://bugzilla.mozilla.org/show_bug.cgi?id=1294299) which has been reviewed by @heycam, @emilio, and @SimonSapin.

This should not be merged until the Gecko side change gets merged into mozilla-central.

r? @heycam

---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/14038)
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components/style/binding_tools/regen.py

@@ -236,10 +236,12 @@ COMPILATION_TARGETS = {
         "target_dir": "../gecko_bindings",
         "blacklist_types": [
             "nsACString_internal",
+            "nsAString_internal",
         ],
         "raw_lines": [
-            "pub use nsstring::nsACString;",
+            "pub use nsstring::{nsACString, nsAString};",
             "type nsACString_internal = nsACString;",
+            "type nsAString_internal = nsAString;"
         ],
         "flags": [
             "--ignore-methods",

components/style/binding_tools/regen_atoms.py

@@ -32,14 +32,14 @@ def msvc32_symbolify(source, ident):
 
 
 class GkAtomSource:
-    PATTERN = re.compile('^GK_ATOM\((.+),\s*"(.*)"\)')
+    PATTERN = re.compile('^GK_ATOM\((?P<ident>.+),\s*"(?P<value>.*)"\)', re.M)
     FILE = "dist/include/nsGkAtomList.h"
     CLASS = "nsGkAtoms"
     TYPE = "nsIAtom"
 
 
 class CSSPseudoElementsAtomSource:
-    PATTERN = re.compile('^CSS_PSEUDO_ELEMENT\((.+),\s*"(.*)",')
+    PATTERN = re.compile('^CSS_PSEUDO_ELEMENT\((?P<ident>.+),\s*"(?P<value>.*)",', re.M)
     FILE = "dist/include/nsCSSPseudoElementList.h"
     CLASS = "nsCSSPseudoElements"
     # NB: nsICSSPseudoElement is effectively the same as a nsIAtom, but we need
@@ -48,16 +48,24 @@ class CSSPseudoElementsAtomSource:
 
 
 class CSSAnonBoxesAtomSource:
-    PATTERN = re.compile('^CSS_ANON_BOX\((.+),\s*"(.*)"\)')
+    PATTERN = re.compile('^CSS_ANON_BOX\((?P<ident>.+),\s*"(?P<value>.*)"\)', re.M)
     FILE = "dist/include/nsCSSAnonBoxList.h"
     CLASS = "nsCSSAnonBoxes"
     TYPE = "nsICSSAnonBoxPseudo"
 
 
+class CSSPropsAtomSource:
+    PATTERN = re.compile('^CSS_PROP_[A-Z]+\(\s*(?P<value>[^,]+),\s*(?P<ident>[^,]+)', re.M)
+    FILE = "dist/include/nsCSSPropList.h"
+    CLASS = "nsCSSProps"
+    TYPE = "nsICSSProperty"
+
+
 SOURCES = [
     GkAtomSource,
     CSSPseudoElementsAtomSource,
     CSSAnonBoxesAtomSource,
+    CSSPropsAtomSource,
 ]
 
 
@@ -95,10 +103,14 @@ def collect_atoms(objdir):
     atoms = []
     for source in SOURCES:
         with open(os.path.join(objdir, source.FILE)) as f:
-            for line in f.readlines():
-                result = re.match(source.PATTERN, line)
-                if result:
-                    atoms.append(Atom(source, result.group(1), result.group(2)))
+            content = f.read()
+        found = set()
+        for match in source.PATTERN.finditer(content):
+            ident = match.group('ident')
+            if ident in found:
+                continue
+            found.add(ident)
+            atoms.append(Atom(source, ident, match.group('value')))
     return atoms
 
 

components/style/gecko_bindings/bindings.rs

@@ -1,7 +1,8 @@
 /* automatically generated by rust-bindgen */
 
-pub use nsstring::nsACString;
+pub use nsstring::{nsACString, nsAString};
 type nsACString_internal = nsACString;
+type nsAString_internal = nsAString;
 pub type ServoComputedValuesStrong = ::gecko_bindings::sugar::ownership::Strong<ServoComputedValues>;
 pub type ServoComputedValuesBorrowedOrNull<'a> = Option<&'a ServoComputedValues>;
 pub type ServoComputedValuesBorrowed<'a> = &'a ServoComputedValues;
@@ -922,16 +923,73 @@ extern "C" {
     pub fn Servo_ParseStyleAttribute(data: *const nsACString_internal)
      -> RawServoDeclarationBlockStrong;
 }
+extern "C" {
+    pub fn Servo_DeclarationBlock_CreateEmpty()
+     -> RawServoDeclarationBlockStrong;
+}
+extern "C" {
+    pub fn Servo_DeclarationBlock_Clone(declarations:
+                                            RawServoDeclarationBlockBorrowed)
+     -> RawServoDeclarationBlockStrong;
+}
 extern "C" {
     pub fn Servo_DeclarationBlock_Equals(a: RawServoDeclarationBlockBorrowed,
                                          b: RawServoDeclarationBlockBorrowed)
      -> bool;
 }
+extern "C" {
+    pub fn Servo_DeclarationBlock_GetCssText(declarations:
+                                                 RawServoDeclarationBlockBorrowed,
+                                             result: *mut nsAString_internal);
+}
 extern "C" {
     pub fn Servo_DeclarationBlock_SerializeOneValue(declarations:
                                                         RawServoDeclarationBlockBorrowed,
                                                     buffer: *mut nsString);
 }
+extern "C" {
+    pub fn Servo_DeclarationBlock_Count(declarations:
+                                            RawServoDeclarationBlockBorrowed)
+     -> u32;
+}
+extern "C" {
+    pub fn Servo_DeclarationBlock_GetNthProperty(declarations:
+                                                     RawServoDeclarationBlockBorrowed,
+                                                 index: u32,
+                                                 result:
+                                                     *mut nsAString_internal)
+     -> bool;
+}
+extern "C" {
+    pub fn Servo_DeclarationBlock_GetPropertyValue(declarations:
+                                                       RawServoDeclarationBlockBorrowed,
+                                                   property: *mut nsIAtom,
+                                                   is_custom: bool,
+                                                   value:
+                                                       *mut nsAString_internal);
+}
+extern "C" {
+    pub fn Servo_DeclarationBlock_GetPropertyIsImportant(declarations:
+                                                             RawServoDeclarationBlockBorrowed,
+                                                         property:
+                                                             *mut nsIAtom,
+                                                         is_custom: bool)
+     -> bool;
+}
+extern "C" {
+    pub fn Servo_DeclarationBlock_SetProperty(declarations:
+                                                  RawServoDeclarationBlockBorrowed,
+                                              property: *mut nsIAtom,
+                                              is_custom: bool,
+                                              value: *mut nsACString_internal,
+                                              is_important: bool) -> bool;
+}
+extern "C" {
+    pub fn Servo_DeclarationBlock_RemoveProperty(declarations:
+                                                     RawServoDeclarationBlockBorrowed,
+                                                 property: *mut nsIAtom,
+                                                 is_custom: bool);
+}
 extern "C" {
     pub fn Servo_CSSSupports(name: *const nsACString_internal,
                              value: *const nsACString_internal) -> bool;

ports/geckolib/glue.rs

@@ -7,6 +7,7 @@ use cssparser::{Parser, ToCss};
 use env_logger;
 use euclid::Size2D;
 use parking_lot::RwLock;
+use std::fmt::Write;
 use std::mem::transmute;
 use std::sync::{Arc, Mutex};
 use style::arc_ptr_eq;
@@ -25,9 +26,9 @@ use style::gecko_bindings::bindings::{RawServoStyleSetBorrowed, RawServoStyleSet
 use style::gecko_bindings::bindings::{RawServoStyleSheetBorrowed, ServoComputedValuesBorrowed};
 use style::gecko_bindings::bindings::{RawServoStyleSheetStrong, ServoComputedValuesStrong};
 use style::gecko_bindings::bindings::{ThreadSafePrincipalHolder, ThreadSafeURIHolder};
+use style::gecko_bindings::bindings::{nsACString, nsAString};
 use style::gecko_bindings::bindings::Gecko_Utf8SliceToString;
 use style::gecko_bindings::bindings::ServoComputedValuesBorrowedOrNull;
-use style::gecko_bindings::bindings::nsACString;
 use style::gecko_bindings::structs::{SheetParsingMode, nsIAtom};
 use style::gecko_bindings::structs::ServoElementSnapshot;
 use style::gecko_bindings::structs::nsRestyleHint;
@@ -420,6 +421,18 @@ pub extern "C" fn Servo_ParseStyleAttribute(data: *const nsACString) -> RawServo
     Arc::new(RwLock::new(GeckoElement::parse_style_attribute(value))).into_strong()
 }
 
+#[no_mangle]
+pub extern "C" fn Servo_DeclarationBlock_CreateEmpty() -> RawServoDeclarationBlockStrong {
+    Arc::new(RwLock::new(PropertyDeclarationBlock { declarations: vec![], important_count: 0 })).into_strong()
+}
+
+#[no_mangle]
+pub extern "C" fn Servo_DeclarationBlock_Clone(declarations: RawServoDeclarationBlockBorrowed)
+                                               -> RawServoDeclarationBlockStrong {
+    let declarations = RwLock::<PropertyDeclarationBlock>::as_arc(&declarations);
+    Arc::new(RwLock::new(declarations.read().clone())).into_strong()
+}
+
 #[no_mangle]
 pub extern "C" fn Servo_DeclarationBlock_AddRef(declarations: RawServoDeclarationBlockBorrowed) {
     unsafe { RwLock::<PropertyDeclarationBlock>::addref(declarations) };
@@ -437,6 +450,13 @@ pub extern "C" fn Servo_DeclarationBlock_Equals(a: RawServoDeclarationBlockBorro
     *RwLock::<PropertyDeclarationBlock>::as_arc(&a).read() == *RwLock::<PropertyDeclarationBlock>::as_arc(&b).read()
 }
 
+#[no_mangle]
+pub extern "C" fn Servo_DeclarationBlock_GetCssText(declarations: RawServoDeclarationBlockBorrowed,
+                                                    result: *mut nsAString) {
+    let declarations = RwLock::<PropertyDeclarationBlock>::as_arc(&declarations);
+    declarations.read().to_css(unsafe { result.as_mut().unwrap() }).unwrap();
+}
+
 #[no_mangle]
 pub extern "C" fn Servo_DeclarationBlock_SerializeOneValue(
     declarations: RawServoDeclarationBlockBorrowed,
@@ -469,6 +489,85 @@ pub extern "C" fn Servo_DeclarationBlock_SerializeOneValue(
     }
 }
 
+#[no_mangle]
+pub extern "C" fn Servo_DeclarationBlock_Count(declarations: RawServoDeclarationBlockBorrowed) -> u32 {
+     let declarations = RwLock::<PropertyDeclarationBlock>::as_arc(&declarations);
+     declarations.read().declarations.len() as u32
+}
+
+#[no_mangle]
+pub extern "C" fn Servo_DeclarationBlock_GetNthProperty(declarations: RawServoDeclarationBlockBorrowed,
+                                                        index: u32, result: *mut nsAString) -> bool {
+    let declarations = RwLock::<PropertyDeclarationBlock>::as_arc(&declarations);
+    if let Some(&(ref decl, _)) = declarations.read().declarations.get(index as usize) {
+        let result = unsafe { result.as_mut().unwrap() };
+        write!(result, "{}", decl.name()).unwrap();
+        true
+    } else {
+        false
+    }
+}
+
+// FIXME Methods of PropertyDeclarationBlock should take atoms directly.
+// This function is just a temporary workaround before that finishes.
+fn get_property_name_from_atom(atom: *mut nsIAtom, is_custom: bool) -> String {
+    let atom = Atom::from(atom);
+    if !is_custom {
+        atom.to_string()
+    } else {
+        let mut result = String::with_capacity(atom.len() as usize + 2);
+        write!(result, "--{}", atom).unwrap();
+        result
+    }
+}
+
+#[no_mangle]
+pub extern "C" fn Servo_DeclarationBlock_GetPropertyValue(declarations: RawServoDeclarationBlockBorrowed,
+                                                          property: *mut nsIAtom, is_custom: bool,
+                                                          value: *mut nsAString) {
+    let declarations = RwLock::<PropertyDeclarationBlock>::as_arc(&declarations);
+    let property = get_property_name_from_atom(property, is_custom);
+    declarations.read().property_value_to_css(&property, unsafe { value.as_mut().unwrap() }).unwrap();
+}
+
+#[no_mangle]
+pub extern "C" fn Servo_DeclarationBlock_GetPropertyIsImportant(declarations: RawServoDeclarationBlockBorrowed,
+                                                                property: *mut nsIAtom, is_custom: bool) -> bool {
+    let declarations = RwLock::<PropertyDeclarationBlock>::as_arc(&declarations);
+    let property = get_property_name_from_atom(property, is_custom);
+    declarations.read().property_priority(&property).important()
+}
+
+#[no_mangle]
+pub extern "C" fn Servo_DeclarationBlock_SetProperty(declarations: RawServoDeclarationBlockBorrowed,
+                                                     property: *mut nsIAtom, is_custom: bool,
+                                                     value: *mut nsACString, is_important: bool) -> bool {
+    let property = get_property_name_from_atom(property, is_custom);
+    let value = unsafe { value.as_ref().unwrap().as_str_unchecked() };
+    // FIXME Needs real URL and ParserContextExtraData.
+    let base_url = &*DUMMY_BASE_URL;
+    let extra_data = ParserContextExtraData::default();
+    if let Ok(decls) = parse_one_declaration(&property, value, &base_url,
+                                             Box::new(StdoutErrorReporter), extra_data) {
+        let mut declarations = RwLock::<PropertyDeclarationBlock>::as_arc(&declarations).write();
+        let importance = if is_important { Importance::Important } else { Importance::Normal };
+        for decl in decls.into_iter() {
+            declarations.set_parsed_declaration(decl, importance);
+        }
+        true
+    } else {
+        false
+    }
+}
+
+#[no_mangle]
+pub extern "C" fn Servo_DeclarationBlock_RemoveProperty(declarations: RawServoDeclarationBlockBorrowed,
+                                                        property: *mut nsIAtom, is_custom: bool) {
+    let declarations = RwLock::<PropertyDeclarationBlock>::as_arc(&declarations);
+    let property = get_property_name_from_atom(property, is_custom);
+    declarations.write().remove_property(&property);
+}
+
 #[no_mangle]
 pub extern "C" fn Servo_CSSSupports(property: *const nsACString, value: *const nsACString) -> bool {
     let property = unsafe { property.as_ref().unwrap().as_str_unchecked() };