Provide suspendable undo manager and test

richtextfx/src/integrationTest/java/org/fxmisc/richtext/api/UndoManagerTests.java

@@ -9,10 +9,12 @@
 import org.fxmisc.richtext.RichTextFXTestBase;
 import org.fxmisc.richtext.StyledTextArea;
 import org.fxmisc.richtext.model.SimpleEditableStyledDocument;
+import org.fxmisc.richtext.model.RichTextChange;
 import org.fxmisc.richtext.model.TextChange;
 import org.fxmisc.richtext.util.UndoUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
+import org.reactfx.SuspendableYes;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
@@ -174,6 +176,20 @@ public void testForBug904() {
  interact( area::undo ); // should not throw Unexpected change received exception 
  }
 
+ @Test
+ public void suspendable_UndoManager_skips_style_check() {
+
+ SuspendableYes suspendUndo = new SuspendableYes();
+ area.setUndoManager( UndoUtils.richTextSuspendableUndoManager( area, suspendUndo ) );
+ write( "some text\n" );
+ interact( () -> suspendUndo.suspendWhile( () -> area.setStyle( 5, 9, "-fx-font-weight: bold;" ) ) );
+ write( "new line" );
+ interact( area::undo ); // should not throw Unexpected change received exception
+
+ area.setUndoManager( UndoUtils.defaultUndoManager( area ) );
+ RichTextChange.skipStyleComparison( false );
+ }
+
  }
 
  public class UsingStyledTextArea extends RichTextFXTestBase {

richtextfx/src/main/java/org/fxmisc/richtext/model/RichTextChange.java

@@ -45,4 +45,31 @@ public final PlainTextChange toPlainTextChange() {
  public final boolean isPlainTextIdentity() {
  return removed.getText().equals(inserted.getText());
  }
+
+ private static boolean skipStyleComparison = false;
+
+ public static void skipStyleComparison( boolean value )
+ {
+ skipStyleComparison = value;
+ }
+
+ /* 
+ * This gets used, by the default UndoManagers supplied by UndoUtils,
+ * to check that a submitted undo/redo matches the change reported. 
+ */
+ public boolean equals( Object other )
+ {
+ if( skipStyleComparison && other instanceof RichTextChange )
+ {
+ PlainTextChange otherChange = ((RichTextChange) other).toPlainTextChange();
+ boolean matches = toPlainTextChange().equals( otherChange );
+ if ( ! matches ) System.err.println(
+ "Plain text comparison mismatch caused by text change"
+ +" during undo manager suspension (styling ignored)."
+ );
+ return matches;
+ }
+
+ return super.equals( other );
+ }
 }

richtextfx/src/main/java/org/fxmisc/richtext/util/UndoUtils.java

@@ -7,6 +7,9 @@
 import org.fxmisc.richtext.model.TextChange;
 import org.fxmisc.undo.UndoManager;
 import org.fxmisc.undo.UndoManagerFactory;
+import org.fxmisc.undo.impl.MultiChangeUndoManagerImpl;
+import org.fxmisc.undo.impl.UnlimitedChangeQueue;
+import org.reactfx.SuspendableYes;
 import org.reactfx.value.Val;
 
 import javafx.beans.value.ObservableBooleanValue;
@@ -121,6 +124,38 @@ public static <PS, SEG, S> UndoManager<List<RichTextChange<PS, SEG, S>>> richTex
  preventMergeDelay);
  };
 
+ /**
+ * Returns an UndoManager with an unlimited history that can undo/redo {@link RichTextChange}s. New changes
+ * emitted from the stream will not be merged with the previous change after {@link #DEFAULT_PREVENT_MERGE_DELAY}
+ * <p><b>Note</b>: that <u>only styling changes</u> may occur <u>during suspension</u> of the undo manager.
+ */
+ public static <PS, SEG, S> UndoManager<List<RichTextChange<PS, SEG, S>>> richTextSuspendableUndoManager(
+ GenericStyledArea<PS, SEG, S> area, SuspendableYes suspendUndo) {
+ return richTextSuspendableUndoManager(area, DEFAULT_PREVENT_MERGE_DELAY, suspendUndo);
+ }
+
+ /**
+ * Returns an UndoManager with an unlimited history that can undo/redo {@link RichTextChange}s. New changes
+ * emitted from the stream will not be merged with the previous change after {@code preventMergeDelay}.
+ * <p><b>Note</b>: that <u>only styling changes</u> may occur <u>during suspension</u> of the undo manager.
+ */
+ public static <PS, SEG, S> UndoManager<List<RichTextChange<PS, SEG, S>>> richTextSuspendableUndoManager(
+ GenericStyledArea<PS, SEG, S> area, Duration preventMergeDelay, SuspendableYes suspendUndo) {
+
+ RichTextChange.skipStyleComparison( true );
+
+ return new MultiChangeUndoManagerImpl<>
+ (
+ new UnlimitedChangeQueue<>(),
+ TextChange::invert,
+ applyMultiRichTextChange(area),
+ TextChange::mergeWith,
+ TextChange::isIdentity,
+ area.multiRichChanges().conditionOn(suspendUndo),
+ preventMergeDelay
+ );
+ };
+
  /**
  * Returns an UndoManager with an unlimited history that can undo/redo {@link PlainTextChange}s. New changes
  * emitted from the stream will not be merged with the previous change