Added Max Instances Property to Workspace Options (#2130)

* Added Max Instances property to Blocks

* eslint cleanup

* eslint cleanup 2

* Moved maxInstances property from block to workspace (as a map of block type to max instances). isDuplicate() changed to correctly handle siblings/branches.

* eslint cleanup

* Changed checking types to map. Added hasBlockLimits. Fixed Nits.

* Added limit_instances test block. eslint fixes.

* fixup! Added limit_instances test block. eslint fixes.

* Changed sorting objects to a private static function of the workspace. Fixed nits. Undeleted .eslintrc

* Reverted .gitignore file.

* Added getBlockTypeCounts() to utils. Added isCapacityAvailable() to workspace. Changed clipboard to save typeCountsMap rather than object.

.gitignore

@@ -11,4 +11,4 @@ npm-debug.log
 tests/compile/main_compressed.js
 tests/compile/*compiler*.jar
 local_build/*compiler*.jar
-local_build/local_blockly_compressed.js
+local_build/local_blockly_compressed.js

core/block.js

@@ -164,6 +164,7 @@ Blockly.Block = function(workspace, prototypeName, opt_id) {
   }
 
   workspace.addTopBlock(this);
+  workspace.addTypedBlock(this);
 
   // Call an initialization function, if it exists.
   if (typeof this.init == 'function') {
@@ -255,6 +256,7 @@ Blockly.Block.prototype.dispose = function(healStack) {
     // Remove this block from the workspace's list of top-most blocks.
     if (this.workspace) {
       this.workspace.removeTopBlock(this);
+      this.workspace.removeTypedBlock(this);
       // Remove from block database.
       delete this.workspace.blockDB_[this.id];
       this.workspace = null;
@@ -668,6 +670,21 @@ Blockly.Block.prototype.setMovable = function(movable) {
   this.movable_ = movable;
 };
 
+/**
+ * Get whether is block is duplicatable or not. If duplicating this block and
+ * descendants will put this block over the workspace's capacity this block is
+ * not duplicatable. If duplicating this block and descendants will put any
+ * type over their maxInstances this block is not duplicatable.
+ * @return {boolean} True if duplicatable.
+ */
+Blockly.Block.prototype.isDuplicatable = function() {
+  if (!this.workspace.hasBlockLimits()) {
+    return true;
+  }
+  return this.workspace.isCapacityAvailable(
+      Blockly.utils.getBlockTypeCounts(this, true));
+};
+
 /**
  * Get whether this block is a shadow block or not.
  * @return {boolean} True if a shadow.

core/blockly.js

@@ -98,6 +98,13 @@ Blockly.clipboardXml_ = null;
  */
 Blockly.clipboardSource_ = null;
 
+/**
+ * Map of types to type counts for the clipboard object and descendants.
+ * @type {Object}
+ * @private
+ */
+Blockly.clipboardTypeCounts_ = null;
+
 /**
  * Cached value for whether 3D is supported.
  * @type {!boolean}
@@ -227,15 +234,18 @@ Blockly.onKeyDown_ = function(e) {
     if (e.keyCode == 86) {
       // 'v' for paste.
       if (Blockly.clipboardXml_) {
-        Blockly.Events.setGroup(true);
         // Pasting always pastes to the main workspace, even if the copy
         // started in a flyout workspace.
         var workspace = Blockly.clipboardSource_;
         if (workspace.isFlyout) {
           workspace = workspace.targetWorkspace;
         }
-        workspace.paste(Blockly.clipboardXml_);
-        Blockly.Events.setGroup(false);
+        if (Blockly.clipboardTypeCounts_ &&
+            workspace.isCapacityAvailable(Blockly.clipboardTypeCounts_)) {
+          Blockly.Events.setGroup(true);
+          workspace.paste(Blockly.clipboardXml_);
+          Blockly.Events.setGroup(false);
+        }
       }
     } else if (e.keyCode == 90) {
       // 'z' for undo 'Z' is for redo.
@@ -273,6 +283,8 @@ Blockly.copy_ = function(toCopy) {
   }
   Blockly.clipboardXml_ = xml;
   Blockly.clipboardSource_ = toCopy.workspace;
+  Blockly.clipboardTypeCounts_ = toCopy.isComment ? null :
+      Blockly.utils.getBlockTypeCounts(toCopy, true);
 };
 
 /**

core/contextmenu.js

@@ -260,11 +260,7 @@ Blockly.ContextMenu.blockHelpOption = function(block) {
  * @package
  */
 Blockly.ContextMenu.blockDuplicateOption = function(block) {
-  var enabled = true;
-  if (block.getDescendants(false).length >
-      block.workspace.remainingCapacity()) {
-    enabled = false;
-  }
+  var enabled = block.isDuplicatable();
   var duplicateOption = {
     text: Blockly.Msg['DUPLICATE_BLOCK'],
     enabled: enabled,

core/flyout_base.js

@@ -228,6 +228,7 @@ Blockly.Flyout.prototype.createDom = function(tagName) {
 Blockly.Flyout.prototype.init = function(targetWorkspace) {
   this.targetWorkspace_ = targetWorkspace;
   this.workspace_.targetWorkspace = targetWorkspace;
+
   // Add scrollbar.
   this.scrollbar_ = new Blockly.Scrollbar(this.workspace_,
       this.horizontalLayout_, false, 'blocklyFlyoutScrollbar');
@@ -729,7 +730,8 @@ Blockly.Flyout.prototype.filterForCapacity_ = function() {
   for (var i = 0, block; block = blocks[i]; i++) {
     if (this.permanentlyDisabled_.indexOf(block) == -1) {
       var allBlocks = block.getDescendants(false);
-      block.setDisabled(allBlocks.length > remainingCapacity);
+      block.setDisabled(allBlocks.length > remainingCapacity ||
+          this.targetWorkspace_.remainingCapacityOfType(block.type) <= 0);
     }
   }
 };

core/options.js

@@ -119,6 +119,7 @@ Blockly.Options = function(options) {
   this.disable = hasDisable;
   this.readOnly = readOnly;
   this.maxBlocks = options['maxBlocks'] || Infinity;
+  this.maxInstances = options['maxInstances'];
   this.pathToMedia = pathToMedia;
   this.hasCategories = hasCategories;
   this.hasScrollbars = hasScrollbars;

core/utils.js

@@ -974,3 +974,32 @@ Blockly.utils.containsNode = function(parent, descendant) {
   return !!(parent.compareDocumentPosition(descendant) &
             Node.DOCUMENT_POSITION_CONTAINED_BY);
 };
+
+/**
+ * Get a map of all the block's descendants mapping their type to the number of
+ *    children with that type.
+ * @param {!Blockly.Block} block The block to map.
+ * @param {boolean=} opt_stripFollowing Optionally ignore all following
+ *    statements (blocks that are not inside a value or statement input
+ *    of the block).
+ * @returns {!Object} Map of types to type counts for descendants of the bock.
+ */
+Blockly.utils.getBlockTypeCounts = function(block, opt_stripFollowing) {
+  var typeCountsMap = Object.create(null);
+  var descendants = block.getDescendants(true);
+  if (opt_stripFollowing) {
+    var nextBlock = block.getNextBlock();
+    if (nextBlock) {
+      var index = descendants.indexOf(nextBlock);
+      descendants.splice(index, descendants.length - index);
+    }
+  }
+  for (var i = 0, checkBlock; checkBlock = descendants[i]; i++) {
+    if (typeCountsMap[checkBlock.type]) {
+      typeCountsMap[checkBlock.type]++;
+    } else {
+      typeCountsMap[checkBlock.type] = 1;
+    }
+  }
+  return typeCountsMap;
+};

core/workspace.js

@@ -85,6 +85,11 @@ Blockly.Workspace = function(opt_options) {
    * @private
    */
   this.blockDB_ = Object.create(null);
+  /**
+   * @type {!Object}
+   * @private
+   */
+  this.typedBlocksDB_ = Object.create(null);
 
   /**
    * A map from variable type to list of variable names.  The lists contain all
@@ -147,6 +152,24 @@ Blockly.Workspace.prototype.dispose = function() {
  */
 Blockly.Workspace.SCAN_ANGLE = 3;
 
+/**
+ * Compare function for sorting objects (blocks, comments, etc) by position;
+ *    top to bottom (with slight LTR or RTL bias).
+ * @param {!Blockly.Block | !Blockly.WorkspaceComment} a The first object to
+ *    compare.
+ * @param {!Blockly.Block | !Blockly.WorkspaceComment} b The second object to
+ *    compare.
+ * @returns {number} The comparison value. This tells Array.sort() how to change
+ *    object a's index.
+ * @private
+ */
+Blockly.Workspace.prototype.sortObjects_ = function(a, b) {
+  var aXY = a.getRelativeToSurfaceXY();
+  var bXY = b.getRelativeToSurfaceXY();
+  return (aXY.y + Blockly.Workspace.prototype.sortObjects_.offset * aXY.x) -
+      (bXY.y + Blockly.Workspace.prototype.sortObjects_.offset * bXY.x);
+};
+
 /**
  * Add a block to the list of top blocks.
  * @param {!Blockly.Block} block Block to add.
@@ -175,16 +198,58 @@ Blockly.Workspace.prototype.getTopBlocks = function(ordered) {
   // Copy the topBlocks_ list.
   var blocks = [].concat(this.topBlocks_);
   if (ordered && blocks.length > 1) {
-    var offset =
+    this.sortObjects_.offset =
         Math.sin(Blockly.utils.toRadians(Blockly.Workspace.SCAN_ANGLE));
     if (this.RTL) {
-      offset *= -1;
+      this.sortObjects_.offset *= -1;
     }
-    blocks.sort(function(a, b) {
-      var aXY = a.getRelativeToSurfaceXY();
-      var bXY = b.getRelativeToSurfaceXY();
-      return (aXY.y + offset * aXY.x) - (bXY.y + offset * bXY.x);
-    });
+    blocks.sort(this.sortObjects_);
+  }
+  return blocks;
+};
+
+/**
+ * Add a block to the list of blocks keyed by type.
+ * @param {!Blockly.Block} block Block to add.
+ */
+Blockly.Workspace.prototype.addTypedBlock = function(block) {
+  if (!this.typedBlocksDB_[block.type]) {
+    this.typedBlocksDB_[block.type] = [];
+  }
+  this.typedBlocksDB_[block.type].push(block);
+};
+
+/**
+ * Remove a block from the list of blocks keyed by type.
+ * @param {!Blockly.Block} block Block to remove.
+ */
+Blockly.Workspace.prototype.removeTypedBlock = function(block) {
+  this.typedBlocksDB_[block.type].splice(this.typedBlocksDB_[block.type]
+      .indexOf(block), 1);
+  if (!this.typedBlocksDB_[block.type].length) {
+    delete this.typedBlocksDB_[block.type];
+  }
+};
+
+/**
+ * Finds the blocks with the associated type and returns them. Blocks are
+ * optionally sorted by position; top to bottom (with slight LTR or RTL bias).
+ * @param {string} type The type of block to search for.
+ * @param {boolean} ordered Sort the list if true.
+ * @return {!Array.<!Blockly.Block>} The blocks of the given type.
+ */
+Blockly.Workspace.prototype.getBlocksByType = function(type, ordered) {
+  if (!this.typedBlocksDB_[type]) {
+    return [];
+  }
+  var blocks = this.typedBlocksDB_[type].slice(0);
+  if (ordered && blocks.length > 1) {
+    this.sortObjects_.offset =
+        Math.sign(Blockly.utils.toRadians(Blockly.Workspace.SCAN_ANGLE));
+    if (this.RTL) {
+      this.sortObjects_.offset *= -1;
+    }
+    blocks.sort(this.sortObjects_);
   }
   return blocks;
 };
@@ -232,16 +297,12 @@ Blockly.Workspace.prototype.getTopComments = function(ordered) {
   // Copy the topComments_ list.
   var comments = [].concat(this.topComments_);
   if (ordered && comments.length > 1) {
-    var offset =
+    this.sortObjects_.offset =
         Math.sin(Blockly.utils.toRadians(Blockly.Workspace.SCAN_ANGLE));
     if (this.RTL) {
-      offset *= -1;
+      this.sortObjects_.offset *= -1;
     }
-    comments.sort(function(a, b) {
-      var aXY = a.getRelativeToSurfaceXY();
-      var bXY = b.getRelativeToSurfaceXY();
-      return (aXY.y + offset * aXY.x) - (bXY.y + offset * bXY.x);
-    });
+    comments.sort(this.sortObjects_);
   }
   return comments;
 };
@@ -455,6 +516,56 @@ Blockly.Workspace.prototype.remainingCapacity = function() {
   return this.options.maxBlocks - this.getAllBlocks().length;
 };
 
+/**
+ * The number of blocks of the given type that may be added to the workspace
+ *    before reaching the maxInstances allowed for that type.
+ * @param {string} type Type of block to return capacity for.
+ * @return {number} Number of blocks of type left.
+ */
+Blockly.Workspace.prototype.remainingCapacityOfType = function(type) {
+  if (!this.options.maxInstances) {
+    return Infinity;
+  }
+  return (this.options.maxInstances[type] || Infinity) -
+      this.getBlocksByType(type).length;
+};
+
+/**
+ * Check if there is remaining capacity for blocks of the given counts to be
+ *    created. If the total number of blocks represented by the map is more than
+ *    the total remaining capacity, it returns false. If a type count is more
+ *    than the remaining capacity for that type, it returns false.
+ * @param {!Object} typeCountsMap A map of types to counts (usually representing
+ *    blocks to be created).
+ * @returns {boolean} True if there is capacity for the given map,
+ *    false otherwise.
+ */
+Blockly.Workspace.prototype.isCapacityAvailable = function(typeCountsMap) {
+  if (!this.hasBlockLimits()) {
+    return true;
+  }
+  var copyableBlocksCount = 0;
+  for (var type in typeCountsMap) {
+    if (typeCountsMap[type] > this.remainingCapacityOfType(type)) {
+      return false;
+    }
+    copyableBlocksCount += typeCountsMap[type];
+  }
+  if (copyableBlocksCount > this.remainingCapacity()) {
+    return false;
+  }
+  return true;
+};
+
+/**
+ * Checks if the workspace has any limits on the maximum number of blocks,
+ *    or the maximum number of blocks of specific types.
+ * @returns {boolean} True if it has block limits, false otherwise.
+ */
+Blockly.Workspace.prototype.hasBlockLimits = function() {
+  return this.options.maxBlocks != Infinity || !!this.options.maxInstances;
+};
+
 /**
  * Undo or redo the previous action.
  * @param {boolean} redo False if undo, true if redo.

tests/blocks/test_blocks.js

@@ -44,6 +44,22 @@ Blockly.defineBlocksWithJsonArray([  // BEGIN JSON EXTRACT
     "output": null,
     "colour": 230
   },
+  {
+    "type": "limit_instances",
+    "message0": "limit 3 instances %1 %2",
+    "args0": [
+      {
+        "type": "input_dummy"
+      },
+      {
+        "type": "input_statement",
+        "name": "STATEMENT"
+      }
+    ],
+    "previousStatement": null,
+    "nextStatement": null,
+    "colour": 230,
+  },
   {
     "type": "example_dropdown_long",
     "message0": "long: %1",
@@ -145,17 +161,17 @@ Blockly.defineBlocksWithJsonArray([  // BEGIN JSON EXTRACT
     "type": "example_angle",
     "message0": "angle: %1",
     "args0": [
-        {
-          "type": "field_angle",
-          "name": "FIELDNAME",
-          "angle": "90",
-          "alt":
-            {
-              "type": "field_label",
-              "text": "NO ANGLE FIELD"
-            }
-        }
-      ]
+      {
+        "type": "field_angle",
+        "name": "FIELDNAME",
+        "angle": "90",
+        "alt":
+          {
+            "type": "field_label",
+            "text": "NO ANGLE FIELD"
+          }
+      }
+    ]
   },
   {
     "type": "example_date",

tests/playground.html

@@ -103,6 +103,7 @@ function start() {
           },
         horizontalLayout: side == 'top' || side == 'bottom',
         maxBlocks: Infinity,
+        maxInstances: {'limit_instances': 3},
         media: '../media/',
         oneBasedIndex: true,
         readOnly: false,
@@ -1080,6 +1081,7 @@ h1 {
       <block type="empty_block_with_mutator"></block>
       <block type="value_to_stack"></block>
       <block type="value_to_statement"></block>
+      <block type="limit_instances"></block>
     </category>
     <category name="Drag">
       <label text="Drag each to the workspace"></label>