Bug 1035774 - Add media feature keys for hover and pointer. r=heycam,emilio

Summary: https://drafts.csswg.org/mediaqueries-4/#hover https://drafts.csswg.org/mediaqueries-4/#pointer In this patch series, we don't introduce any-hover and any-pointer media features yet, but functionalities for them on each platform backends will be introduced in this patch series, so eIntID_AllPointerCapabilities and relevant stuff is added in this patch for the convenience that each platform backends can be reviewed at once. Differential Revision: https://phabricator.services.mozilla.com/D3296
2018-08-14 17:13:04 +09:00 · 2018-08-14 17:13:04 +09:00 · ef03e2a299
--- a/layout/style/ServoBindings.h
+++ b/layout/style/ServoBindings.h
@ -56,6 +56,7 @@ namespace mozilla {
  class ComputedStyle;
  class StyleSheet;
  class ServoElementSnapshotTable;
+  enum class PointerCapabilities : uint8_t;
 }
 using mozilla::FontFamilyList;
 using mozilla::FontFamilyName;
@ -750,6 +751,7 @@ uint32_t Gecko_MediaFeatures_GetColorDepth(nsIDocument*);
 void Gecko_MediaFeatures_GetDeviceSize(nsIDocument*, nscoord* width, nscoord* height);
 float Gecko_MediaFeatures_GetResolution(nsIDocument*);
 bool Gecko_MediaFeatures_PrefersReducedMotion(nsIDocument*);
+mozilla::PointerCapabilities Gecko_MediaFeatures_PrimaryPointerCapabilities(nsIDocument*);
 float Gecko_MediaFeatures_GetDevicePixelRatio(nsIDocument*);
 bool Gecko_MediaFeatures_HasSystemMetric(nsIDocument*,
                                         nsAtom* metric,
--- a/layout/style/ServoBindings.toml
+++ b/layout/style/ServoBindings.toml
@ -257,6 +257,7 @@ whitelist-types = [
    "mozilla::StyleShapeRadius",
    "mozilla::StyleGrid.*",
    "mozilla::UpdateAnimationsTasks",
+    "mozilla::PointerCapabilities",
    "mozilla::LookAndFeel",
    "mozilla::gfx::Float",
    "mozilla::gfx::FontVariation",
@ -620,6 +621,7 @@ structs-types = [
    "ComputedStyleStrong",
    "EffectCompositor_CascadeLevel",
    "UpdateAnimationsTasks",
+    "PointerCapabilities",
    "ParsingMode",
    "InheritTarget",
    "DocumentMatchingFunction",
--- a/layout/style/ServoTypes.h
+++ b/layout/style/ServoTypes.h
@ -125,6 +125,17 @@ enum class InheritTarget {
  PlaceholderFrame,
 };

+// Represents values for interaction media features.
+// https://drafts.csswg.org/mediaqueries-4/#mf-interaction
+enum class PointerCapabilities : uint8_t {
+  None = 0,
+  Coarse = 1 << 0,
+  Fine = 1 << 1,
+  Hover = 1 << 2,
+};
+
+MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(PointerCapabilities)
+
 // These measurements are obtained for both the UA cache and the Stylist, but
 // not all the fields are used in both cases.
 class ServoStyleSetSizes
--- a/layout/style/nsMediaFeatures.cpp
+++ b/layout/style/nsMediaFeatures.cpp
@ -262,6 +262,28 @@ Gecko_MediaFeatures_PrefersReducedMotion(nsIDocument* aDocument)
  return LookAndFeel::GetInt(LookAndFeel::eIntID_PrefersReducedMotion, 0) == 1;
 }

+PointerCapabilities
+Gecko_MediaFeatures_PrimaryPointerCapabilities(nsIDocument* aDocument)
+{
+  // The default value is mouse-type pointer.
+  const PointerCapabilities kDefaultCapabilities =
+    PointerCapabilities::Fine | PointerCapabilities::Hover;
+
+  if (nsContentUtils::ShouldResistFingerprinting(aDocument)) {
+    return kDefaultCapabilities;
+  }
+
+  int32_t intValue;
+  nsresult rv =
+    LookAndFeel::GetInt(LookAndFeel::eIntID_PrimaryPointerCapabilities,
+                        &intValue);
+  if (NS_FAILED(rv)) {
+    return kDefaultCapabilities;
+  }
+
+  return static_cast<PointerCapabilities>(intValue);
+}
+
 /* static */ void
 nsMediaFeatures::InitSystemMetrics()
 {
--- a/layout/style/test/mochitest.ini
+++ b/layout/style/test/mochitest.ini
@ -257,6 +257,7 @@ skip-if = android_version == '18' #debug-only failure; timed out #Android 4.3 aw
 [test_media_queries_dynamic_xbl.html]
 [test_media_query_list.html]
 [test_media_query_serialization.html]
+[test_mq_hover_and_pointer.html]
 [test_moz_device_pixel_ratio.html]
 [test_namespace_rule.html]
 [test_non_content_accessible_properties.html]
--- a/layout/style/test/test_mq_hover_and_pointer.html
+++ b/layout/style/test/test_mq_hover_and_pointer.html
@ -0,0 +1,122 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1035774
+-->
+<head>
+  <meta charset="utf-8">
+  <title>Test for Bug 1035774</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/AddTask.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1035774">Mozilla Bug 1035774</a>
+<p id="display"></p>
+<div id="content" style="display: none">
+
+</div>
+<pre id="test">
+</pre>
+<script>
+
+const NO_POINTER            = 0x00;
+const COARSE_POINTER        = 0x01;
+const FINE_POINTER          = 0x02;
+const HOVER_CAPABLE_POINTER = 0x04;
+
+add_task(async () => {
+  await SpecialPowers.pushPrefEnv({
+    set: [ ['privacy.resistFingerprinting', true] ]
+  });
+
+  // When resistFingerprinting is enabled, we pretend that the system has a
+  // mouse pointer.
+  ok(!matchMedia("(pointer: none)").matches,
+                 "Doesn't match (pointer: none)");
+  ok(!matchMedia("(pointer: coarse)").matches,
+                 "Doesn't match (pointer: coarse)");
+  ok(matchMedia("(pointer: fine)").matches, "Matches (pointer: fine)");
+  ok(matchMedia("(pointer)").matches, "Matches (pointer)");
+
+  ok(!matchMedia("(hover: none)").matches, "Doesn't match (hover: none)");
+  ok(matchMedia("(hover: hover)").matches, "Matches (hover: hover)");
+  ok(matchMedia("(hover)").matches, "Matches (hover)");
+
+  await SpecialPowers.flushPrefEnv();
+});
+
+add_task(async () => {
+  // No pointer.
+  await SpecialPowers.pushPrefEnv({
+    set: [ ['ui.primaryPointerCapabilities', NO_POINTER] ]
+  });
+
+  ok(matchMedia("(pointer: none)").matches, "Matches (pointer: none)");
+  ok(!matchMedia("(pointer: coarse)").matches,
+                 "Doesn't match (pointer: coarse)");
+  ok(!matchMedia("(pointer: fine)").matches, "Doesn't match (pointer: fine)");
+  ok(!matchMedia("(pointer)").matches, "Matches (pointer)");
+
+  ok(matchMedia("(hover: none)").matches, "Matches (hover: none)");
+  ok(!matchMedia("(hover: hover)").matches, "Doesn't match (hover: hover)");
+  ok(!matchMedia("(hover)").matches, "Doesn't match (hover)");
+});
+
+add_task(async () => {
+  // Mouse type pointer.
+  await SpecialPowers.pushPrefEnv({
+    set: [ ['ui.primaryPointerCapabilities', FINE_POINTER | HOVER_CAPABLE_POINTER] ]
+  });
+
+  ok(!matchMedia("(pointer: none)").matches,
+                 "Doesn't match (pointer: none)");
+  ok(!matchMedia("(pointer: coarse)").matches,
+                 "Doesn't match (pointer: coarse)");
+  ok(matchMedia("(pointer: fine)").matches, "Matches (pointer: fine)");
+  ok(matchMedia("(pointer)").matches, "Matches (pointer)");
+
+  ok(!matchMedia("(hover: none)").matches, "Doesn't match (hover: none)");
+  ok(matchMedia("(hover: hover)").matches, "Matches (hover: hover)");
+  ok(matchMedia("(hover)").matches, "Matches (hover)");
+});
+
+add_task(async () => {
+  // Mouse type pointer.
+  await SpecialPowers.pushPrefEnv({
+    set: [ ['ui.primaryPointerCapabilities',
+            FINE_POINTER |
+            HOVER_CAPABLE_POINTER] ]
+  });
+
+  ok(!matchMedia("(pointer: none)").matches,
+                 "Doesn't match (pointer: none)");
+  ok(!matchMedia("(pointer: coarse)").matches,
+                 "Doesn't match (pointer: coarse)");
+  ok(matchMedia("(pointer: fine)").matches, "Matches (pointer: fine)");
+  ok(matchMedia("(pointer)").matches, "Matches (pointer)");
+
+  ok(!matchMedia("(hover: none)").matches, "Doesn't match (hover: none)");
+  ok(matchMedia("(hover: hover)").matches, "Matches (hover: hover)");
+  ok(matchMedia("(hover)").matches, "Matches (hover)");
+});
+
+add_task(async () => {
+  // Touch screen.
+  await SpecialPowers.pushPrefEnv({
+    set: [ ['ui.primaryPointerCapabilities', COARSE_POINTER] ]
+  });
+
+  ok(!matchMedia("(pointer: none)").matches, "Doesn't match (pointer: none)");
+  ok(matchMedia("(pointer: coarse)").matches, "Matches (pointer: coarse)");
+  ok(!matchMedia("(pointer: fine)").matches, "Doesn't match (pointer: fine)");
+  ok(matchMedia("(pointer)").matches, "Matches (pointer)");
+
+  ok(matchMedia("(hover: none)").matches, "Match (hover: none)");
+  ok(!matchMedia("(hover: hover)").matches, "Doesn't match (hover: hover)");
+  ok(!matchMedia("(hover)").matches, "Doesn't match (hover)");
+});
+
+</script>
+</body>
+</html>
--- a/servo/components/style/gecko/media_features.rs
+++ b/servo/components/style/gecko/media_features.rs
@ -8,6 +8,7 @@ use Atom;
 use app_units::Au;
 use euclid::Size2D;
 use gecko_bindings::bindings;
+use gecko_bindings::structs;
 use media_queries::Device;
 use media_queries::media_feature::{AllowsRanges, ParsingRequirements};
 use media_queries::media_feature::{MediaFeatureDescription, Evaluator};
@ -300,6 +301,66 @@ fn eval_prefers_reduced_motion(device: &Device, query_value: Option<PrefersReduc
    }
 }

+/// https://drafts.csswg.org/mediaqueries-4/#mf-interaction
+bitflags! {
+    struct PointerCapabilities: u8 {
+        const COARSE = structs::PointerCapabilities_Coarse;
+        const FINE = structs::PointerCapabilities_Fine;
+        const HOVER = structs::PointerCapabilities_Hover;
+    }
+}
+
+#[derive(Debug, Copy, Clone, FromPrimitive, ToCss, Parse)]
+#[repr(u8)]
+enum Pointer {
+    None,
+    Coarse,
+    Fine,
+}
+
+fn primary_pointer_capabilities(device: &Device) -> PointerCapabilities {
+    PointerCapabilities::from_bits_truncate(
+        unsafe { bindings::Gecko_MediaFeatures_PrimaryPointerCapabilities(device.document()) }
+    )
+}
+
+/// https://drafts.csswg.org/mediaqueries-4/#pointer
+fn eval_pointer(device: &Device, query_value: Option<Pointer>) -> bool {
+    let pointer_capabilities = primary_pointer_capabilities(device);
+    let query_value = match query_value {
+        Some(v) => v,
+        None => return !pointer_capabilities.is_empty(),
+    };
+
+    match query_value {
+        Pointer::None => pointer_capabilities.is_empty(),
+        Pointer::Coarse => pointer_capabilities.intersects(PointerCapabilities::COARSE),
+        Pointer::Fine => pointer_capabilities.intersects(PointerCapabilities::FINE),
+    }
+}
+
+#[derive(Debug, Copy, Clone, FromPrimitive, ToCss, Parse)]
+#[repr(u8)]
+enum Hover {
+    None,
+    Hover,
+}
+
+/// https://drafts.csswg.org/mediaqueries-4/#hover
+fn eval_hover(device: &Device, query_value: Option<Hover>) -> bool {
+    let pointer_capabilities = primary_pointer_capabilities(device);
+    let can_hover = pointer_capabilities.intersects(PointerCapabilities::HOVER);
+    let query_value = match query_value {
+        Some(v) => v,
+        None => return can_hover,
+    };
+
+    match query_value {
+        Hover::None => !can_hover,
+        Hover::Hover => can_hover,
+    }
+}
+
 fn eval_moz_is_glyph(
    device: &Device,
    query_value: Option<bool>,
@ -390,7 +451,7 @@ lazy_static! {
    /// 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 ref MEDIA_FEATURES: [MediaFeatureDescription; 43] = [
+    pub static ref MEDIA_FEATURES: [MediaFeatureDescription; 45] = [
        feature!(
            atom!("width"),
            AllowsRanges::Yes,
@ -509,6 +570,18 @@ lazy_static! {
            keyword_evaluator!(eval_prefers_reduced_motion, PrefersReducedMotion),
            ParsingRequirements::empty(),
        ),
+        feature!(
+            atom!("pointer"),
+            AllowsRanges::No,
+            keyword_evaluator!(eval_pointer, Pointer),
+            ParsingRequirements::empty(),
+        ),
+        feature!(
+            atom!("hover"),
+            AllowsRanges::No,
+            keyword_evaluator!(eval_hover, Hover),
+            ParsingRequirements::empty(),
+        ),

        // Internal -moz-is-glyph media feature: applies only inside SVG glyphs.
        // Internal because it is really only useful in the user agent anyway
--- a/widget/LookAndFeel.h
+++ b/widget/LookAndFeel.h
@ -447,7 +447,22 @@ public:
      * 0: no-preference
      * 1: reduce
      */
+
     eIntID_PrefersReducedMotion,
+     /**
+      * Corresponding to PointerCapabilities in ServoTypes.h
+      * 0: None
+      * 1: Coarse
+      * 2: Fine
+      * 4: Hover
+      */
+     eIntID_PrimaryPointerCapabilities,
+     /**
+      * Corresponding to union of PointerCapabilities values in ServoTypes.h
+      * E.g. if there is a mouse and a digitizer, the value will be
+      * 'Coarse | Fine | Hover'.
+      */
+     eIntID_AllPointerCapabilities,
  };

  /**
--- a/widget/nsXPLookAndFeel.cpp
+++ b/widget/nsXPLookAndFeel.cpp
@ -141,6 +141,12 @@ nsLookAndFeelIntPref nsXPLookAndFeel::sIntPrefs[] =
  { "ui.prefersReducedMotion",
    eIntID_PrefersReducedMotion,
    false, 0 },
+  { "ui.primaryPointerCapabilities",
+    eIntID_PrimaryPointerCapabilities,
+    false, 6 /* fine and hover-capable pointer, i.e. mouse-type */ },
+  { "ui.allPointerCapabilities",
+    eIntID_AllPointerCapabilities,
+    false, 6 /* fine and hover-capable pointer, i.e. mouse-type */ },
 };

 nsLookAndFeelFloatPref nsXPLookAndFeel::sFloatPrefs[] =
--- a/xpcom/ds/StaticAtoms.py
+++ b/xpcom/ds/StaticAtoms.py
@ -1383,6 +1383,7 @@ STATIC_ATOMS = [
    Atom("patternTransform", "patternTransform"),
    Atom("patternUnits", "patternUnits"),
    Atom("pc", "pc"),
+    Atom("pointer", "pointer"),
    Atom("pointer_events", "pointer-events"),
    Atom("points", "points"),
    Atom("pointsAtX", "pointsAtX"),