fixed "redrop" (redo)

some cases that were buggy in v5 still remain to be so, but what worked in v5 again works in v6 now..

HISTORY.md

@@ -12,11 +12,15 @@
     * changing the type of a custom block from reporter to command in the block editor changes the prototype instead of adding another one
     * deleting project notes in the "save" dialog now also deletes them in the saved project
     * items in list-boxes such as the project list are no longer auto-translated
+    * fixed a redo issue
 * **Translation Updates:**
     * Catalan, thanks, Joan!
     * Norwegian, thanks, Olav!
     * German
 
+### 2020-09-14
+* blocks: fixed "redrop" (redo)
+
 ### 2020-09-12
 * morphic: don't auto-translate ListMorph items
 

snap.html

@@ -8,7 +8,7 @@
         <script src="src/morphic.js?version=2020-09-12"></script>
         <script src="src/symbols.js?version=2020-07-21"></script>
         <script src="src/widgets.js?version=2020-07-27"></script>
-        <script src="src/blocks.js?version=2020-09-04"></script>
+        <script src="src/blocks.js?version=2020-09-14"></script>
         <script src="src/threads.js?version=2020-09-02"></script>
         <script src="src/objects.js?version=2020-09-04"></script>
         <script src="src/gui.js?version=2020-09-07"></script>

src/blocks.js

@@ -158,7 +158,7 @@ CustomCommandBlockMorph, SymbolMorph, ToggleButtonMorph, DialMorph*/
 
 // Global stuff ////////////////////////////////////////////////////////
 
-modules.blocks = '2020-September-04';
+modules.blocks = '2020-September-14';
 
 var SyntaxElementMorph;
 var BlockMorph;
@@ -7373,10 +7373,17 @@ ScriptsMorph.prototype.recoverLastDrop = function (forRedrop) {
         }
     } else if (dropped instanceof ReporterBlockMorph) {
         if (rec.lastDropTarget) {
-            rec.lastDropTarget.replaceInput(
-                rec.lastDroppedBlock,
-                rec.lastReplacedInput
-            );
+            if (forRedrop) {
+                rec.lastDropTarget.replaceInput(
+                    rec.lastReplacedInput,
+                    rec.lastDroppedBlock
+                );
+            } else {
+                rec.lastDropTarget.replaceInput(
+                    rec.lastDroppedBlock,
+                    rec.lastReplacedInput
+                );
+            }
             rec.lastDropTarget.fixBlockColor(null, true);
             if (rec.lastPreservedBlocks) {
                 rec.lastPreservedBlocks.forEach(morph =>