Fix duplication of variables and re-write variable ids in referencing fields.

src/engine/target.js

@@ -269,7 +269,7 @@ class Target extends EventEmitter {
 
     /**
      * Renames the variable with the given id to newName.
-     * @param {string} id Id of renamed variable.
+     * @param {string} id Id of variable to rename.
      * @param {string} newName New name for the variable.
      */
     renameVariable (id, newName) {
@@ -301,7 +301,7 @@ class Target extends EventEmitter {
 
     /**
      * Removes the variable with the given id from the dictionary of variables.
-     * @param {string} id Id of renamed variable.
+     * @param {string} id Id of variable to delete.
      */
     deleteVariable (id) {
         if (this.variables.hasOwnProperty(id)) {
@@ -313,6 +313,48 @@ class Target extends EventEmitter {
         }
     }
 
+    /**
+     * Create a clone of the variable with the given id from the dictionary of
+     * this target's variables.
+     * @param {string} id Id of variable to duplicate.
+     * @return {?Variable} The duplicated variable, or null if
+     * the original variable was not found.
+     */
+    duplicateVariable (id) {
+        if (this.variables.hasOwnProperty(id)) {
+            const originalVariable = this.variables[id];
+            const newVariable = new Variable(
+                null, // generate a new uid
+                originalVariable.name,
+                originalVariable.type,
+                originalVariable.isCloud
+            );
+            newVariable.value = originalVariable.value;
+            return newVariable;
+        }
+        return null;
+    }
+
+    /**
+     * Duplicate the dictionary of this target's variables as part of duplicating.
+     * this target or making a clone.
+     * @param {object} blocks Block container for the target being duplicated
+     * @return {object} The duplicated dictionary of variables
+     */
+    duplicateVariables (blocks) {
+        const allVarRefs = blocks.getAllVariableAndListReferences();
+        return Object.keys(this.variables).reduce((accum, varId) => {
+            const newVariable = this.duplicateVariable(varId);
+            accum[newVariable.id] = newVariable;
+            const currVarRefs = allVarRefs[varId];
+            if (currVarRefs) {
+                this.mergeVariables(varId, newVariable.id, currVarRefs);
+            }
+
+            return accum;
+        }, {});
+    }
+
     /**
      * Post/edit sprite info.
      * @param {object} data An object with sprite info data to set.

src/sprites/rendered-target.js

@@ -1003,7 +1003,7 @@ class RenderedTarget extends Target {
         newClone.currentCostume = this.currentCostume;
         newClone.rotationStyle = this.rotationStyle;
         newClone.effects = JSON.parse(JSON.stringify(this.effects));
-        newClone.variables = JSON.parse(JSON.stringify(this.variables));
+        newClone.variables = this.duplicateVariables();
         newClone.initDrawable(StageLayering.SPRITE_LAYER);
         newClone.updateAllDrawableProperties();
         // Place behind the current target.
@@ -1029,7 +1029,7 @@ class RenderedTarget extends Target {
             newTarget.currentCostume = this.currentCostume;
             newTarget.rotationStyle = this.rotationStyle;
             newTarget.effects = JSON.parse(JSON.stringify(this.effects));
-            newTarget.variables = JSON.parse(JSON.stringify(this.variables));
+            newTarget.variables = this.duplicateVariables(newTarget.blocks);
             newTarget.updateAllDrawableProperties();
             newTarget.goBehindOther(this);
             return newTarget;