diff options
Diffstat (limited to 'dom/base/Element.h')
| -rw-r--r-- | dom/base/Element.h | 74 |
1 files changed, 57 insertions, 17 deletions
diff --git a/dom/base/Element.h b/dom/base/Element.h index 6b55cf8cd..6f60c9ad0 100644 --- a/dom/base/Element.h +++ b/dom/base/Element.h @@ -537,25 +537,50 @@ public: * values will not actually be compared if we aren't notifying and we don't * have mutation listeners (in which case it's cheap to just return false * and let the caller go ahead and set the value). - * @param aOldValue Set to the old value of the attribute, but only if there - * are event listeners. If set, the type of aOldValue will be either + * @param aOldValue [out] Set to the old value of the attribute, but only if + * there are event listeners. If set, the type of aOldValue will be either * nsAttrValue::eString or nsAttrValue::eAtom. - * @param aModType Set to nsIDOMMutationEvent::MODIFICATION or to + * @param aModType [out] Set to nsIDOMMutationEvent::MODIFICATION or to * nsIDOMMutationEvent::ADDITION, but only if this helper returns true - * @param aHasListeners Set to true if there are mutation event listeners - * listening for NS_EVENT_BITS_MUTATION_ATTRMODIFIED + * @param aHasListeners [out] Set to true if there are mutation event + * listeners listening for NS_EVENT_BITS_MUTATION_ATTRMODIFIED + * @param aOldValueSet [out] Indicates whether an old attribute value has been + * stored in aOldValue. The bool will be set to true if a value was stored. */ bool MaybeCheckSameAttrVal(int32_t aNamespaceID, nsIAtom* aName, nsIAtom* aPrefix, const nsAttrValueOrString& aValue, bool aNotify, nsAttrValue& aOldValue, - uint8_t* aModType, bool* aHasListeners); + uint8_t* aModType, bool* aHasListeners, + bool* aOldValueSet); + + /** + * Notifies mutation listeners if aNotify is true, there are mutation + * listeners, and the attribute value is changing. + * + * @param aNamespaceID The namespace of the attribute + * @param aName The local name of the attribute + * @param aPrefix The prefix of the attribute + * @param aValue The value that the attribute is being changed to + * @param aNotify If true, mutation listeners will be notified if they exist + * and the attribute value is changing + * @param aOldValue [out] Set to the old value of the attribute, but only if + * there are event listeners. If set, the type of aOldValue will be either + * nsAttrValue::eString or nsAttrValue::eAtom. + * @param aModType [out] Set to nsIDOMMutationEvent::MODIFICATION or to + * nsIDOMMutationEvent::ADDITION, but only if this helper returns true + * @param aHasListeners [out] Set to true if there are mutation event + * listeners listening for NS_EVENT_BITS_MUTATION_ATTRMODIFIED + * @param aOldValueSet [out] Indicates whether an old attribute value has been + * stored in aOldValue. The bool will be set to true if a value was stored. + */ bool OnlyNotifySameValueSet(int32_t aNamespaceID, nsIAtom* aName, nsIAtom* aPrefix, const nsAttrValueOrString& aValue, bool aNotify, nsAttrValue& aOldValue, - uint8_t* aModType, bool* aHasListeners); + uint8_t* aModType, bool* aHasListeners, + bool* aOldValueSet); virtual nsresult SetAttr(int32_t aNameSpaceID, nsIAtom* aName, nsIAtom* aPrefix, const nsAString& aValue, bool aNotify) override; @@ -1261,7 +1286,10 @@ protected: * its current value) is !StoresOwnData() --- in which * case the current value is probably already useless. * If the current value is StoresOwnData() (or absent), - * aOldValue will not be used. + * aOldValue will not be used. aOldValue will only be set + * in certain circumstances (there are mutation + * listeners, element is a custom element, attribute was + * not previously unset). Otherwise it will be null. * @param aParsedValue parsed new value of attribute. Replaced by the * old value of the attribute. This old value is only * useful if either it or the new value is StoresOwnData. @@ -1275,7 +1303,7 @@ protected: nsresult SetAttrAndNotify(int32_t aNamespaceID, nsIAtom* aName, nsIAtom* aPrefix, - const nsAttrValue& aOldValue, + const nsAttrValue* aOldValue, nsAttrValue& aParsedValue, uint8_t aModType, bool aFireMutation, @@ -1320,14 +1348,21 @@ protected: * * @param aDocument the current document of this node (an optimization) * @param aName the name of the attribute - * @param aValue the nsAttrValue to set + * @param aValue the nsAttrValue to set. Will be swapped with the existing + * value of the attribute if the attribute already exists. + * @param [out] aValueWasSet If the attribute was not set previously, + * aValue will be swapped with an empty attribute + * and aValueWasSet will be set to false. Otherwise, + * aValueWasSet will be set to true and aValue will + * contain the previous value set. * @param [out] aRetval the nsresult status of the operation, if any. * @return true if the setting was attempted, false otherwise. */ - virtual bool SetMappedAttribute(nsIDocument* aDocument, - nsIAtom* aName, - nsAttrValue& aValue, - nsresult* aRetval); + virtual bool SetAndSwapMappedAttribute(nsIDocument* aDocument, + nsIAtom* aName, + nsAttrValue& aValue, + bool* aValueWasSet, + nsresult* aRetval); /** * Hook that is called by Element::SetAttr to allow subclasses to @@ -1355,19 +1390,24 @@ protected: /** * Hook that is called by Element::SetAttr to allow subclasses to * deal with attribute sets. This will only be called after we have called - * SetAndTakeAttr and AttributeChanged (that is, after we have actually set - * the attr). It will always be called under a scriptblocker. + * SetAndSwapAttr (that is, after we have actually set the attr). It will + * always be called under a scriptblocker. * * @param aNamespaceID the namespace of the attr being set * @param aName the localname of the attribute being set * @param aValue the value it's being set to. If null, the attr is being * removed. + * @param aOldValue the value that the attribute had previously. If null, + * the attr was not previously set. This argument may not have the + * correct value for SVG elements, or other cases in which the + * attribute value doesn't store its own data * @param aNotify Whether we plan to notify document observers. */ // Note that this is inlined so that when subclasses call it it gets // inlined. Those calls don't go through a vtable. virtual nsresult AfterSetAttr(int32_t aNamespaceID, nsIAtom* aName, - const nsAttrValue* aValue, bool aNotify) + const nsAttrValue* aValue, + const nsAttrValue* aOldValue, bool aNotify) { return NS_OK; } |