From 46a569ef4595609ed0324df458324054a66738d6 Mon Sep 17 00:00:00 2001
From: CanadaHonk <oj@oojmed.com>
Date: Tue, 28 Mar 2023 08:01:49 +0000
Subject: [PATCH] style: Implement scripting media feature

Implemented the scripting media feature.

Not locked behind a pref as it does not do anything new or particularly
give new data which could be used for fingerprinting (see <noscript>,
etc).

Also added new WPT tests (none previously). Not supported in any other
browsers yet.

Test page: https://goose.icu/media-scripting

Differential Revision: https://phabricator.services.mozilla.com/D172995
---
 components/style/gecko/media_features.rs | 34 +++++++++++++++++++++++-
 1 file changed, 33 insertions(+), 1 deletion(-)

diff --git a/components/style/gecko/media_features.rs b/components/style/gecko/media_features.rs
index 7b014b24159..ca59d311ef9 100644
--- a/components/style/gecko/media_features.rs
+++ b/components/style/gecko/media_features.rs
@@ -563,6 +563,32 @@ fn eval_moz_platform(_: &Context, query_value: Option<Platform>) -> bool {
     unsafe { bindings::Gecko_MediaFeatures_MatchesPlatform(query_value) }
 }
 
+/// Values for the scripting media feature.
+/// https://drafts.csswg.org/mediaqueries-5/#scripting
+#[derive(Clone, Copy, Debug, FromPrimitive, Parse, PartialEq, ToCss)]
+#[repr(u8)]
+pub enum Scripting {
+    /// Scripting is not supported or not enabled
+    None,
+    /// Scripting is supported and enabled, but only for initial page load
+    /// We will never match this value as it is intended for non-browser user agents,
+    /// but it is part of the spec so we should still parse it.
+    /// See: https://github.com/w3c/csswg-drafts/issues/8621
+    InitialOnly,
+    /// Scripting is supported and enabled
+    Enabled
+}
+
+/// https://drafts.csswg.org/mediaqueries-5/#scripting
+fn eval_scripting(context: &Context, query_value: Option<Scripting>) -> bool {
+    let scripting =
+        unsafe { bindings::Gecko_MediaFeatures_Scripting(context.device().document()) };
+    match query_value {
+        Some(v) => v == scripting,
+        None => scripting != Scripting::None,
+    }
+}
+
 fn eval_moz_windows_non_native_menus(context: &Context) -> bool {
     unsafe { bindings::Gecko_MediaFeatures_WindowsNonNativeMenus(context.device().document()) }
 }
@@ -643,7 +669,7 @@ macro_rules! bool_pref_feature {
 /// to support new types in these entries and (2) ensuring that either
 /// nsPresContext::MediaFeatureValuesChanged is called when the value that
 /// would be returned by the evaluator function could change.
-pub static MEDIA_FEATURES: [QueryFeatureDescription; 65] = [
+pub static MEDIA_FEATURES: [QueryFeatureDescription; 66] = [
     feature!(
         atom!("width"),
         AllowsRanges::Yes,
@@ -826,6 +852,12 @@ pub static MEDIA_FEATURES: [QueryFeatureDescription; 65] = [
         keyword_evaluator!(eval_video_dynamic_range, DynamicRange),
         FeatureFlags::empty(),
     ),
+    feature!(
+        atom!("scripting"),
+        AllowsRanges::No,
+        keyword_evaluator!(eval_scripting, Scripting),
+        FeatureFlags::empty(),
+    ),
     // Evaluates to the preferred color scheme for content. Only useful in
     // chrome context, where the chrome color-scheme and the content
     // color-scheme might differ.