Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 519 insertions, 0 deletions

diff --git a/layout/style/nsTransitionManager.cpp b/layout/style/nsTransitionManager.cpp
new file mode 100644
index 0000000000..014c0375da
--- /dev/null
+++ b/layout/style/nsTransitionManager.cpp
@@ -0,0 +1,519 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+/* Code to start and animate CSS transitions. */
+
+#include "nsTransitionManager.h"
+#include "mozilla/dom/Document.h"
+#include "nsAnimationManager.h"
+
+#include "nsIContent.h"
+#include "mozilla/ComputedStyle.h"
+#include "mozilla/MemoryReporting.h"
+#include "nsCSSPropertyIDSet.h"
+#include "mozilla/EffectSet.h"
+#include "mozilla/ElementAnimationData.h"
+#include "mozilla/EventDispatcher.h"
+#include "mozilla/ServoBindings.h"
+#include "mozilla/StyleAnimationValue.h"
+#include "mozilla/dom/DocumentTimeline.h"
+#include "mozilla/dom/Element.h"
+#include "nsIFrame.h"
+#include "nsCSSProps.h"
+#include "nsCSSPseudoElements.h"
+#include "nsDisplayList.h"
+#include "nsRFPService.h"
+#include "nsStyleChangeList.h"
+#include "mozilla/RestyleManager.h"
+
+using mozilla::dom::CSSTransition;
+using mozilla::dom::DocumentTimeline;
+using mozilla::dom::KeyframeEffect;
+
+using namespace mozilla;
+using namespace mozilla::css;
+
+static inline bool ExtractNonDiscreteComputedValue(
+    nsCSSPropertyID aProperty, const ComputedStyle& aComputedStyle,
+    AnimationValue& aAnimationValue) {
+  if (Servo_Property_IsDiscreteAnimatable(aProperty) &&
+      aProperty != eCSSProperty_visibility) {
+    return false;
+  }
+
+  aAnimationValue.mServo =
+      Servo_ComputedValues_ExtractAnimationValue(&aComputedStyle, aProperty)
+          .Consume();
+  return !!aAnimationValue.mServo;
+}
+
+bool nsTransitionManager::UpdateTransitions(dom::Element* aElement,
+                                            PseudoStyleType aPseudoType,
+                                            const ComputedStyle& aOldStyle,
+                                            const ComputedStyle& aNewStyle) {
+  if (mPresContext->Medium() == nsGkAtoms::print) {
+    // For print or print preview, ignore transitions.
+    return false;
+  }
+
+  MOZ_ASSERT(mPresContext->IsDynamic());
+  if (aNewStyle.StyleDisplay()->mDisplay == StyleDisplay::None) {
+    StopAnimationsForElement(aElement, aPseudoType);
+    return false;
+  }
+
+  auto* collection = CSSTransitionCollection::Get(aElement, aPseudoType);
+  return DoUpdateTransitions(*aNewStyle.StyleUIReset(), aElement, aPseudoType,
+                             collection, aOldStyle, aNewStyle);
+}
+
+// This function expands the shorthands and "all" keyword specified in
+// transition-property, and then execute |aHandler| on the expanded longhand.
+// |aHandler| should be a lamda function which accepts nsCSSPropertyID.
+template <typename T>
+static void ExpandTransitionProperty(nsCSSPropertyID aProperty, T aHandler) {
+  if (aProperty == eCSSPropertyExtra_no_properties ||
+      aProperty == eCSSPropertyExtra_variable ||
+      aProperty == eCSSProperty_UNKNOWN) {
+    // Nothing to do.
+    return;
+  }
+
+  // FIXME(emilio): This should probably just use the "all" shorthand id, and we
+  // should probably remove eCSSPropertyExtra_all_properties.
+  if (aProperty == eCSSPropertyExtra_all_properties) {
+    for (nsCSSPropertyID p = nsCSSPropertyID(0);
+         p < eCSSProperty_COUNT_no_shorthands; p = nsCSSPropertyID(p + 1)) {
+      if (!nsCSSProps::IsEnabled(p, CSSEnabledState::ForAllContent)) {
+        continue;
+      }
+      aHandler(p);
+    }
+  } else if (nsCSSProps::IsShorthand(aProperty)) {
+    CSSPROPS_FOR_SHORTHAND_SUBPROPERTIES(subprop, aProperty,
+                                         CSSEnabledState::ForAllContent) {
+      aHandler(*subprop);
+    }
+  } else {
+    aHandler(aProperty);
+  }
+}
+
+bool nsTransitionManager::DoUpdateTransitions(
+    const nsStyleUIReset& aStyle, dom::Element* aElement,
+    PseudoStyleType aPseudoType, CSSTransitionCollection*& aElementTransitions,
+    const ComputedStyle& aOldStyle, const ComputedStyle& aNewStyle) {
+  MOZ_ASSERT(!aElementTransitions || &aElementTransitions->mElement == aElement,
+             "Element mismatch");
+
+  // Per http://lists.w3.org/Archives/Public/www-style/2009Aug/0109.html
+  // I'll consider only the transitions from the number of items in
+  // 'transition-property' on down, and later ones will override earlier
+  // ones (tracked using |propertiesChecked|).
+  bool startedAny = false;
+  nsCSSPropertyIDSet propertiesChecked;
+  for (uint32_t i = aStyle.mTransitionPropertyCount; i--;) {
+    // We're not going to look at any further transitions, so we can just avoid
+    // looking at this if we know it will not start any transitions.
+    if (i == 0 && aStyle.GetTransitionCombinedDuration(i).seconds <= 0.0f) {
+      continue;
+    }
+
+    ExpandTransitionProperty(
+        aStyle.GetTransitionProperty(i), [&](nsCSSPropertyID aProperty) {
+          // We might have something to transition.  See if any of the
+          // properties in question changed and are animatable.
+          startedAny |= ConsiderInitiatingTransition(
+              aProperty, aStyle, i, aElement, aPseudoType, aElementTransitions,
+              aOldStyle, aNewStyle, propertiesChecked);
+        });
+  }
+
+  // Stop any transitions for properties that are no longer in
+  // 'transition-property', including finished transitions.
+  // Also stop any transitions (and remove any finished transitions)
+  // for properties that just changed (and are still in the set of
+  // properties to transition), but for which we didn't just start the
+  // transition.  This can happen delay and duration are both zero, or
+  // because the new value is not interpolable.
+  if (aElementTransitions) {
+    bool checkProperties =
+        aStyle.GetTransitionProperty(0) != eCSSPropertyExtra_all_properties;
+    nsCSSPropertyIDSet allTransitionProperties;
+    if (checkProperties) {
+      for (uint32_t i = aStyle.mTransitionPropertyCount; i-- != 0;) {
+        ExpandTransitionProperty(
+            aStyle.GetTransitionProperty(i), [&](nsCSSPropertyID aProperty) {
+              allTransitionProperties.AddProperty(
+                  nsCSSProps::Physicalize(aProperty, aNewStyle));
+            });
+      }
+    }
+
+    OwningCSSTransitionPtrArray& animations = aElementTransitions->mAnimations;
+    size_t i = animations.Length();
+    MOZ_ASSERT(i != 0, "empty transitions list?");
+    AnimationValue currentValue;
+    do {
+      --i;
+      CSSTransition* anim = animations[i];
+      const nsCSSPropertyID property = anim->TransitionProperty();
+      if (
+          // Properties no longer in `transition-property`.
+          (checkProperties && !allTransitionProperties.HasProperty(property)) ||
+          // Properties whose computed values changed but for which we did not
+          // start a new transition (because delay and duration are both zero,
+          // or because the new value is not interpolable); a new transition
+          // would have anim->ToValue() matching currentValue.
+          !ExtractNonDiscreteComputedValue(property, aNewStyle, currentValue) ||
+          currentValue != anim->ToValue()) {
+        // Stop the transition.
+        DoCancelTransition(aElement, aPseudoType, aElementTransitions, i);
+      }
+    } while (i != 0);
+  }
+
+  return startedAny;
+}
+
+static Keyframe& AppendKeyframe(double aOffset, nsCSSPropertyID aProperty,
+                                AnimationValue&& aValue,
+                                nsTArray<Keyframe>& aKeyframes) {
+  Keyframe& frame = *aKeyframes.AppendElement();
+  frame.mOffset.emplace(aOffset);
+  MOZ_ASSERT(aValue.mServo);
+  RefPtr<StyleLockedDeclarationBlock> decl =
+      Servo_AnimationValue_Uncompute(aValue.mServo).Consume();
+  frame.mPropertyValues.AppendElement(
+      PropertyValuePair(aProperty, std::move(decl)));
+  return frame;
+}
+
+static nsTArray<Keyframe> GetTransitionKeyframes(nsCSSPropertyID aProperty,
+                                                 AnimationValue&& aStartValue,
+                                                 AnimationValue&& aEndValue) {
+  nsTArray<Keyframe> keyframes(2);
+
+  AppendKeyframe(0.0, aProperty, std::move(aStartValue), keyframes);
+  AppendKeyframe(1.0, aProperty, std::move(aEndValue), keyframes);
+
+  return keyframes;
+}
+
+static bool IsTransitionable(nsCSSPropertyID aProperty) {
+  return Servo_Property_IsTransitionable(aProperty);
+}
+
+static Maybe<CSSTransition::ReplacedTransitionProperties>
+GetReplacedTransitionProperties(const CSSTransition* aTransition,
+                                const DocumentTimeline* aTimelineToMatch) {
+  Maybe<CSSTransition::ReplacedTransitionProperties> result;
+
+  // Transition needs to be currently running on the compositor to be
+  // replaceable.
+  if (!aTransition || !aTransition->HasCurrentEffect() ||
+      !aTransition->IsRunningOnCompositor() ||
+      aTransition->GetStartTime().IsNull()) {
+    return result;
+  }
+
+  // Transition needs to be running on the same timeline.
+  if (aTransition->GetTimeline() != aTimelineToMatch) {
+    return result;
+  }
+
+  // The transition needs to have a keyframe effect.
+  const KeyframeEffect* keyframeEffect =
+      aTransition->GetEffect() ? aTransition->GetEffect()->AsKeyframeEffect()
+                               : nullptr;
+  if (!keyframeEffect) {
+    return result;
+  }
+
+  // The keyframe effect needs to be a simple transition of the original
+  // transition property (i.e. not replaced with something else).
+  if (keyframeEffect->Properties().Length() != 1 ||
+      keyframeEffect->Properties()[0].mSegments.Length() != 1 ||
+      keyframeEffect->Properties()[0].mProperty !=
+          aTransition->TransitionProperty()) {
+    return result;
+  }
+
+  const AnimationPropertySegment& segment =
+      keyframeEffect->Properties()[0].mSegments[0];
+
+  result.emplace(CSSTransition::ReplacedTransitionProperties(
+      {aTransition->GetStartTime().Value(), aTransition->PlaybackRate(),
+       keyframeEffect->SpecifiedTiming(), segment.mTimingFunction,
+       segment.mFromValue, segment.mToValue}));
+
+  return result;
+}
+
+bool nsTransitionManager::ConsiderInitiatingTransition(
+    nsCSSPropertyID aProperty, const nsStyleUIReset& aStyle,
+    uint32_t transitionIdx, dom::Element* aElement, PseudoStyleType aPseudoType,
+    CSSTransitionCollection*& aElementTransitions,
+    const ComputedStyle& aOldStyle, const ComputedStyle& aNewStyle,
+    nsCSSPropertyIDSet& aPropertiesChecked) {
+  // IsShorthand itself will assert if aProperty is not a property.
+  MOZ_ASSERT(!nsCSSProps::IsShorthand(aProperty), "property out of range");
+  NS_ASSERTION(
+      !aElementTransitions || &aElementTransitions->mElement == aElement,
+      "Element mismatch");
+
+  aProperty = nsCSSProps::Physicalize(aProperty, aNewStyle);
+
+  // A later item in transition-property already specified a transition for
+  // this property, so we ignore this one.
+  //
+  // See http://lists.w3.org/Archives/Public/www-style/2009Aug/0109.html .
+  if (aPropertiesChecked.HasProperty(aProperty)) {
+    return false;
+  }
+
+  aPropertiesChecked.AddProperty(aProperty);
+
+  if (!IsTransitionable(aProperty)) {
+    return false;
+  }
+
+  float delay = aStyle.GetTransitionDelay(transitionIdx).ToMilliseconds();
+
+  // The spec says a negative duration is treated as zero.
+  float duration = std::max(
+      aStyle.GetTransitionDuration(transitionIdx).ToMilliseconds(), 0.0f);
+
+  // If the combined duration of this transition is 0 or less don't start a
+  // transition.
+  if (delay + duration <= 0.0f) {
+    return false;
+  }
+
+  AnimationValue startValue, endValue;
+  bool haveValues =
+      ExtractNonDiscreteComputedValue(aProperty, aOldStyle, startValue) &&
+      ExtractNonDiscreteComputedValue(aProperty, aNewStyle, endValue);
+
+  bool haveChange = startValue != endValue;
+
+  bool shouldAnimate = haveValues && haveChange &&
+                       startValue.IsInterpolableWith(aProperty, endValue);
+
+  bool haveCurrentTransition = false;
+  size_t currentIndex = nsTArray<KeyframeEffect>::NoIndex;
+  const CSSTransition* oldTransition = nullptr;
+  if (aElementTransitions) {
+    OwningCSSTransitionPtrArray& animations = aElementTransitions->mAnimations;
+    for (size_t i = 0, i_end = animations.Length(); i < i_end; ++i) {
+      if (animations[i]->TransitionProperty() == aProperty) {
+        haveCurrentTransition = true;
+        currentIndex = i;
+        oldTransition = animations[i];
+        break;
+      }
+    }
+  }
+
+  // If we got a style change that changed the value to the endpoint
+  // of the currently running transition, we don't want to interrupt
+  // its timing function.
+  // This needs to be before the !shouldAnimate && haveCurrentTransition
+  // case below because we might be close enough to the end of the
+  // transition that the current value rounds to the final value.  In
+  // this case, we'll end up with shouldAnimate as false (because
+  // there's no value change), but we need to return early here rather
+  // than cancel the running transition because shouldAnimate is false!
+  //
+  // Likewise, if we got a style change that changed the value to the
+  // endpoint of our finished transition, we also don't want to start
+  // a new transition for the reasons described in
+  // https://lists.w3.org/Archives/Public/www-style/2015Jan/0444.html .
+  if (haveCurrentTransition && haveValues &&
+      aElementTransitions->mAnimations[currentIndex]->ToValue() == endValue) {
+    // GetAnimationRule already called RestyleForAnimation.
+    return false;
+  }
+
+  if (!shouldAnimate) {
+    if (haveCurrentTransition) {
+      // We're in the middle of a transition, and just got a non-transition
+      // style change to something that we can't animate.  This might happen
+      // because we got a non-transition style change changing to the current
+      // in-progress value (which is particularly easy to cause when we're
+      // currently in the 'transition-delay').  It also might happen because we
+      // just got a style change to a value that can't be interpolated.
+      DoCancelTransition(aElement, aPseudoType, aElementTransitions,
+                         currentIndex);
+    }
+    return false;
+  }
+
+  AnimationValue startForReversingTest = startValue;
+  double reversePortion = 1.0;
+
+  // If the new transition reverses an existing one, we'll need to
+  // handle the timing differently.
+  if (haveCurrentTransition &&
+      aElementTransitions->mAnimations[currentIndex]->HasCurrentEffect() &&
+      oldTransition && oldTransition->StartForReversingTest() == endValue) {
+    // Compute the appropriate negative transition-delay such that right
+    // now we'd end up at the current position.
+    double valuePortion =
+        oldTransition->CurrentValuePortion() * oldTransition->ReversePortion() +
+        (1.0 - oldTransition->ReversePortion());
+    // A timing function with negative y1 (or y2!) might make
+    // valuePortion negative.  In this case, we still want to apply our
+    // reversing logic based on relative distances, not make duration
+    // negative.
+    if (valuePortion < 0.0) {
+      valuePortion = -valuePortion;
+    }
+    // A timing function with y2 (or y1!) greater than one might
+    // advance past its terminal value.  It's probably a good idea to
+    // clamp valuePortion to be at most one to preserve the invariant
+    // that a transition will complete within at most its specified
+    // time.
+    if (valuePortion > 1.0) {
+      valuePortion = 1.0;
+    }
+
+    // Negative delays are essentially part of the transition
+    // function, so reduce them along with the duration, but don't
+    // reduce positive delays.
+    if (delay < 0.0f && std::isfinite(delay)) {
+      delay *= valuePortion;
+    }
+
+    if (std::isfinite(duration)) {
+      duration *= valuePortion;
+    }
+
+    startForReversingTest = oldTransition->ToValue();
+    reversePortion = valuePortion;
+  }
+
+  TimingParams timing = TimingParamsFromCSSParams(
+      duration, delay, 1.0 /* iteration count */,
+      dom::PlaybackDirection::Normal, dom::FillMode::Backwards);
+
+  const StyleComputedTimingFunction& tf =
+      aStyle.GetTransitionTimingFunction(transitionIdx);
+  if (!tf.IsLinearKeyword()) {
+    timing.SetTimingFunction(Some(tf));
+  }
+
+  RefPtr<CSSTransition> transition = DoCreateTransition(
+      aProperty, aElement, aPseudoType, aNewStyle, aElementTransitions,
+      std::move(timing), std::move(startValue), std::move(endValue),
+      std::move(startForReversingTest), reversePortion);
+  if (!transition) {
+    return false;
+  }
+
+  OwningCSSTransitionPtrArray& transitions = aElementTransitions->mAnimations;
+#ifdef DEBUG
+  for (size_t i = 0, i_end = transitions.Length(); i < i_end; ++i) {
+    MOZ_ASSERT(
+        i == currentIndex || transitions[i]->TransitionProperty() != aProperty,
+        "duplicate transitions for property");
+  }
+#endif
+  if (haveCurrentTransition) {
+    // If this new transition is replacing an existing transition that is
+    // running on the compositor, we store select parameters from the replaced
+    // transition so that later, once all scripts have run, we can update the
+    // start value of the transition using TimeStamp::Now(). This allows us to
+    // avoid a large jump when starting a new transition when the main thread
+    // lags behind the compositor.
+    const dom::DocumentTimeline* timeline = aElement->OwnerDoc()->Timeline();
+    auto replacedTransitionProperties =
+        GetReplacedTransitionProperties(oldTransition, timeline);
+    if (replacedTransitionProperties) {
+      transition->SetReplacedTransition(
+          std::move(replacedTransitionProperties.ref()));
+    }
+
+    transitions[currentIndex]->CancelFromStyle(PostRestyleMode::IfNeeded);
+    oldTransition = nullptr;  // Clear pointer so it doesn't dangle
+    transitions[currentIndex] = transition;
+  } else {
+    // XXX(Bug 1631371) Check if this should use a fallible operation as it
+    // pretended earlier.
+    transitions.AppendElement(transition);
+  }
+
+  if (auto* effectSet = EffectSet::Get(aElement, aPseudoType)) {
+    effectSet->UpdateAnimationGeneration(mPresContext);
+  }
+
+  return true;
+}
+
+already_AddRefed<CSSTransition> nsTransitionManager::DoCreateTransition(
+    nsCSSPropertyID aProperty, dom::Element* aElement,
+    PseudoStyleType aPseudoType, const mozilla::ComputedStyle& aNewStyle,
+    CSSTransitionCollection*& aElementTransitions, TimingParams&& aTiming,
+    AnimationValue&& aStartValue, AnimationValue&& aEndValue,
+    AnimationValue&& aStartForReversingTest, double aReversePortion) {
+  dom::DocumentTimeline* timeline = aElement->OwnerDoc()->Timeline();
+  KeyframeEffectParams effectOptions;
+  RefPtr<KeyframeEffect> keyframeEffect = new KeyframeEffect(
+      aElement->OwnerDoc(), OwningAnimationTarget(aElement, aPseudoType),
+      std::move(aTiming), effectOptions);
+
+  keyframeEffect->SetKeyframes(
+      GetTransitionKeyframes(aProperty, std::move(aStartValue),
+                             std::move(aEndValue)),
+      &aNewStyle, timeline);
+
+  if (NS_WARN_IF(MOZ_UNLIKELY(!keyframeEffect->IsValidTransition()))) {
+    return nullptr;
+  }
+
+  RefPtr<CSSTransition> animation =
+      new CSSTransition(mPresContext->Document()->GetScopeObject());
+  animation->SetOwningElement(OwningElementRef(*aElement, aPseudoType));
+  animation->SetTimelineNoUpdate(timeline);
+  animation->SetCreationSequence(
+      mPresContext->RestyleManager()->GetAnimationGeneration());
+  animation->SetEffectFromStyle(keyframeEffect);
+  animation->SetReverseParameters(std::move(aStartForReversingTest),
+                                  aReversePortion);
+  animation->PlayFromStyle();
+
+  if (!aElementTransitions) {
+    aElementTransitions =
+        &aElement->EnsureAnimationData().EnsureTransitionCollection(
+            *aElement, aPseudoType);
+    if (!aElementTransitions->isInList()) {
+      AddElementCollection(aElementTransitions);
+    }
+  }
+  return animation.forget();
+}
+
+void nsTransitionManager::DoCancelTransition(
+    dom::Element* aElement, PseudoStyleType aPseudoType,
+    CSSTransitionCollection*& aElementTransitions, size_t aIndex) {
+  MOZ_ASSERT(aElementTransitions);
+  OwningCSSTransitionPtrArray& transitions = aElementTransitions->mAnimations;
+  CSSTransition* transition = transitions[aIndex];
+
+  if (transition->HasCurrentEffect()) {
+    if (auto* effectSet = EffectSet::Get(aElement, aPseudoType)) {
+      effectSet->UpdateAnimationGeneration(mPresContext);
+    }
+  }
+  transition->CancelFromStyle(PostRestyleMode::IfNeeded);
+  transitions.RemoveElementAt(aIndex);
+
+  if (transitions.IsEmpty()) {
+    aElementTransitions->Destroy();
+    // |aElementTransitions| is now a dangling pointer!
+    aElementTransitions = nullptr;
+  }
+}