From 50ec050fdc7b2103dd0def47d4ba6fd8422f9122 Mon Sep 17 00:00:00 2001
From: Jurgen <jurgen@ivory.web.za>
Date: Tue, 26 Nov 2019 10:10:47 +0200
Subject: [PATCH] Added test and anchor properties fix (#877)

---
 .../richtext/api/selection/PositionTests.java | 13 +++++++++++++
 .../richtext/CaretSelectionBindImpl.java      | 19 ++++++++++++-------
 2 files changed, 25 insertions(+), 7 deletions(-)

diff --git a/richtextfx/src/integrationTest/java/org/fxmisc/richtext/api/selection/PositionTests.java b/richtextfx/src/integrationTest/java/org/fxmisc/richtext/api/selection/PositionTests.java
index d250917b2..7048af6ff 100644
--- a/richtextfx/src/integrationTest/java/org/fxmisc/richtext/api/selection/PositionTests.java
+++ b/richtextfx/src/integrationTest/java/org/fxmisc/richtext/api/selection/PositionTests.java
@@ -159,6 +159,7 @@ public void end_position_is_correct_when_change_occurs_after_position() {
         });
     }
 
+    @Test
     public void deletion_which_includes_selection_and_which_occurs_at_end_of_area_moves_selection_to_new_area_end() {
         interact(() -> {
            selection.selectRange(area.getLength(), area.getLength());
@@ -167,4 +168,16 @@ public void deletion_which_includes_selection_and_which_occurs_at_end_of_area_mo
            assertEquals(area.getLength(), selection.getEndPosition());
         });
     }
+    
+    @Test
+    public void anchor_updates_correctly_with_listener_attached() {
+        interact(() -> {
+            area.clear();
+            area.anchorProperty().addListener( (ob,ov,nv) -> nv++ );
+            area.appendText("asdf");
+            area.selectRange(1,2);
+            assertEquals("s",area.getSelectedText());
+            assertEquals(1,area.getAnchor());
+         });
+    }
 }
diff --git a/richtextfx/src/main/java/org/fxmisc/richtext/CaretSelectionBindImpl.java b/richtextfx/src/main/java/org/fxmisc/richtext/CaretSelectionBindImpl.java
index 525e5ec65..0be828b92 100644
--- a/richtextfx/src/main/java/org/fxmisc/richtext/CaretSelectionBindImpl.java
+++ b/richtextfx/src/main/java/org/fxmisc/richtext/CaretSelectionBindImpl.java
@@ -135,9 +135,15 @@ public void configureSelectionPath(SelectionPath path) {
     public final boolean isBeingUpdated() { return beingUpdated.get(); }
     public final ObservableValue<Boolean> beingUpdatedProperty() { return beingUpdated; }
 
-    private final Var<Boolean> internalStartedByAnchor = Var.newSimpleVar(true);
-    private final SuspendableVal<Boolean> startedByAnchor = internalStartedByAnchor.suspendable();
-    private boolean anchorIsStart() { return startedByAnchor.getValue(); }
+    private final Var<BooleanEvent> internalStartedByAnchor = Var.newSimpleVar( new BooleanEvent( true ) );
+    private final SuspendableVal<BooleanEvent> startedByAnchor = internalStartedByAnchor.suspendable();
+    private boolean anchorIsStart() { return startedByAnchor.getValue().get(); }
+
+    private class BooleanEvent {  // See #874
+        public BooleanEvent( boolean b ) { value = b; }
+        public boolean get() { return value; }
+        private final boolean value;
+    }
 
     private Subscription subscription = () -> {};
 
@@ -166,7 +172,7 @@ public void configureSelectionPath(SelectionPath path) {
         }
 
         Val<Tuple3<Integer, Integer, Integer>> anchorPositions = startedByAnchor.flatMap(b ->
-                b
+                b.get()
                     ? Val.constant(Tuples.t(getStartPosition(), getStartParagraphIndex(), getStartColumnPosition()))
                     : Val.constant(Tuples.t(getEndPosition(), getEndParagraphIndex(), getEndColumnPosition()))
         );
@@ -431,7 +437,7 @@ public void displaceCaret(int position) {
     public void displaceSelection(int startPosition, int endPosition) {
         doUpdate(() -> {
             delegateSelection.selectRange(startPosition, endPosition);
-            internalStartedByAnchor.setValue(startPosition < endPosition);
+            internalStartedByAnchor.setValue( new BooleanEvent( startPosition < endPosition ) );
         });
     }
 
@@ -449,8 +455,7 @@ public void dispose() {
     private void doSelect(int startPosition, int endPosition, boolean anchorIsStart) {
         doUpdate(() -> {
             delegateSelection.selectRange(startPosition, endPosition);
-            internalStartedByAnchor.setValue(anchorIsStart);
-
+            internalStartedByAnchor.setValue( new BooleanEvent( anchorIsStart ) );
             delegateCaret.moveTo(anchorIsStart ? endPosition : startPosition);
         });
     }