Bug 1737919 part 4: Update cached spelling errors when a spelling error is added without the text changing. r=morgan,smaug

We already have an nsISelectionListener, but that only tells us that a change happened somewhere in the selection, not which range changed.
We don't want to push a cache update for all ranges when only one changed.
Therefore, this patch adds an accessibility notification in mozInlineSpellChecker::AddRange.
We don't need this for removed ranges because the text will change for any spelling error corrections and text updates trigger spelling error cache updates.

Differential Revision: https://phabricator.services.mozilla.com/D147244

accessible/base/SelectionManager.cpp

@@ -13,11 +13,13 @@
 #include "nsCoreUtils.h"
 #include "nsEventShell.h"
 #include "nsFrameSelection.h"
+#include "TextLeafRange.h"
 
 #include "mozilla/PresShell.h"
 #include "mozilla/dom/Document.h"
 #include "mozilla/dom/Selection.h"
 #include "mozilla/dom/Element.h"
+#include "mozilla/StaticPrefs_accessibility.h"
 
 using namespace mozilla;
 using namespace mozilla::a11y;
@@ -226,4 +228,14 @@ void SelectionManager::ProcessSelectionChanged(SelData* aSelData) {
   }
 }
 
+void SelectionManager::SpellCheckRangeAdded(const nsRange& aRange) {
+  // Events are fired in SelectionManager::NotifySelectionChanged. This is only
+  // used to push cache updates.
+  if (StaticPrefs::accessibility_cache_enabled_AtStartup()) {
+    dom::Document* doc = aRange.GetStartContainer()->OwnerDoc();
+    MOZ_ASSERT(doc);
+    TextLeafPoint::UpdateCachedSpellingError(doc, aRange);
+  }
+}
+
 SelectionManager::~SelectionManager() = default;

accessible/base/SelectionManager.h

@@ -9,6 +9,8 @@
 #include "nsISelectionListener.h"
 #include "mozilla/WeakPtr.h"
 
+class nsRange;
+
 namespace mozilla {
 
 class PresShell;
@@ -106,6 +108,18 @@ class SelectionManager : public nsISelectionListener {
     mAccWithCaret = nullptr;
   }
 
+  /**
+   * Called by mozInlineSpellChecker when a spell check range is added.
+   * nsISelectionListener isn't sufficient for spelling errors, since it only
+   * tells us that there was a change, not which range changed. We don't want
+   * to unnecessarily push a cache update for all Accessibles in the entire
+   * selection.
+   * We don't need an equivalent notification for removals because a spelling
+   * error correction is triggered by a text change and text changes trigger a
+   * cache update already.
+   */
+  void SpellCheckRangeAdded(const nsRange& aRange);
+
   ~SelectionManager();
 
  protected:

accessible/base/TextLeafRange.cpp

@@ -8,15 +8,18 @@
 
 #include "HyperTextAccessible-inl.h"
 #include "mozilla/a11y/Accessible.h"
+#include "mozilla/a11y/CacheConstants.h"
 #include "mozilla/a11y/DocAccessible.h"
 #include "mozilla/a11y/DocAccessibleParent.h"
 #include "mozilla/a11y/LocalAccessible.h"
 #include "mozilla/BinarySearch.h"
 #include "mozilla/Casting.h"
 #include "mozilla/dom/CharacterData.h"
+#include "mozilla/dom/Document.h"
 #include "mozilla/intl/Segmenter.h"
 #include "mozilla/intl/WordBreaker.h"
 #include "mozilla/StaticPrefs_layout.h"
+#include "nsAccessibilityService.h"
 #include "nsAccUtils.h"
 #include "nsBlockFrame.h"
 #include "nsContentUtils.h"
@@ -24,6 +27,7 @@
 #include "nsIAccessiblePivot.h"
 #include "nsILineIterator.h"
 #include "nsINode.h"
+#include "nsRange.h"
 #include "nsStyleStructInlines.h"
 #include "nsTArray.h"
 #include "nsTextFrame.h"
@@ -1236,6 +1240,32 @@ nsTArray<int32_t> TextLeafPoint::GetSpellingErrorOffsets(
   return offsets;
 }
 
+/* static */
+void TextLeafPoint::UpdateCachedSpellingError(dom::Document* aDocument,
+                                              const nsRange& aRange) {
+  DocAccessible* docAcc = GetExistingDocAccessible(aDocument);
+  if (!docAcc) {
+    return;
+  }
+  LocalAccessible* startAcc = docAcc->GetAccessible(aRange.GetStartContainer());
+  LocalAccessible* endAcc = docAcc->GetAccessible(aRange.GetEndContainer());
+  if (!startAcc || !endAcc) {
+    return;
+  }
+  for (Accessible* acc = startAcc; acc; acc = NextLeaf(acc)) {
+    if (acc->IsTextLeaf()) {
+      docAcc->QueueCacheUpdate(acc->AsLocal(), CacheDomain::Spelling);
+    }
+    if (acc == endAcc) {
+      // Subtle: We check this here rather than in the loop condition because
+      // we want to include endAcc but stop once we reach it. Putting it in the
+      // loop condition would mean we stop at endAcc, but we would also exclude
+      // it; i.e. we wouldn't push the cache for it.
+      break;
+    }
+  }
+}
+
 already_AddRefed<AccAttributes> TextLeafPoint::GetTextAttributesLocalAcc(
     bool aIncludeDefaults) const {
   LocalAccessible* acc = mAcc->AsLocal();

accessible/base/TextLeafRange.h

@@ -13,7 +13,14 @@
 #include "nsDirection.h"
 #include "nsIAccessibleText.h"
 
-namespace mozilla::a11y {
+class nsRange;
+
+namespace mozilla {
+namespace dom {
+class Document;
+}
+
+namespace a11y {
 class Accessible;
 class LocalAccessible;
 
@@ -136,6 +143,12 @@ class TextLeafPoint final {
    */
   static nsTArray<int32_t> GetSpellingErrorOffsets(LocalAccessible* aAcc);
 
+  /**
+   * Queue a cache update for a spelling error in a given DOM range.
+   */
+  static void UpdateCachedSpellingError(dom::Document* aDocument,
+                                        const nsRange& aRange);
+
   /**
    * Find the start of a run of text attributes in a specific direction.
    * A text attributes run is a span of text where the attributes are the same.
@@ -212,6 +225,7 @@ class TextLeafRange final {
   TextLeafPoint mEnd;
 };
 
-}  // namespace mozilla::a11y
+}  // namespace a11y
+}  // namespace mozilla
 
 #endif

extensions/spellcheck/src/mozInlineSpellChecker.cpp

@@ -53,6 +53,9 @@
 #include "mozilla/dom/MouseEvent.h"
 #include "mozilla/dom/Selection.h"
 #include "mozInlineSpellWordUtil.h"
+#ifdef ACCESSIBILITY
+#  include "nsAccessibilityService.h"
+#endif
 #include "nsCOMPtr.h"
 #include "nsCRT.h"
 #include "nsGenericHTMLElement.h"
@@ -1879,6 +1882,11 @@ nsresult mozInlineSpellChecker::AddRange(Selection* aSpellCheckSelection,
       rv = err.StealNSResult();
     } else {
       mNumWordsInSpellSelection++;
+#ifdef ACCESSIBILITY
+      if (nsAccessibilityService* accService = GetAccService()) {
+        accService->SpellCheckRangeAdded(*aRange);
+      }
+#endif
     }
   }