From f9e0552c11cecb98605557710b241606f605cb66 Mon Sep 17 00:00:00 2001
From: Tim Dawborn <tim.dawborn@gmail.com>
Date: Wed, 28 Dec 2016 12:26:53 +1100
Subject: [PATCH] Add an `allInputsConnected` method to `Block` and `Workspace`
 to test whether all trees in the block forest have their inputs filled. An
 optional argument controls whether or not shadow blocks are counted as being
 filled. Recommitting changes off `develop` instead of `master` as per
 discussion in PR #791.

---
 core/block.js     | 34 ++++++++++++++++++++++++++++++++++
 core/workspace.js | 17 +++++++++++++++++
 2 files changed, 51 insertions(+)

diff --git a/core/block.js b/core/block.js
index 4730c1cd6..25f09ee14 100644
--- a/core/block.js
+++ b/core/block.js
@@ -1335,3 +1335,37 @@ Blockly.Block.prototype.moveBy = function(dx, dy) {
 Blockly.Block.prototype.makeConnection_ = function(type) {
   return new Blockly.Connection(this, type);
 };
+
+/**
+ * Recursively checks whether all statement and value inputs are filled with
+ * blocks. Also checks all following statement blocks in this stack.
+ * @param {boolean=} opt_shadowBlocksAreFilled An optional argument controlling
+ *     whether shadow blocks are counted as filled. Defaults to true.
+ * @return {boolean} True if all inputs are filled, false otherwise.
+ */
+Blockly.Block.prototype.allInputsFilled = function(opt_shadowBlocksAreFilled) {
+  // Handle the default value for the optional argument.
+  if (opt_shadowBlocksAreFilled === undefined) {
+    opt_shadowBlocksAreFilled = true;
+  }
+
+  for (var i = 0, input; input = this.inputList[i]; i++) {
+    if (!input.connection) {
+      continue;
+    }
+    var target = input.connection.targetBlock();
+    if (!target || !target.allInputsFilled(opt_shadowBlocksAreFilled)) {
+      return false;
+    }
+    if (!opt_shadowBlocksAreFilled && target.isShadow()) {
+      return false;
+    }
+  }
+
+  var next = this.getNextBlock();
+  if (next) {
+    return next.allInputsFilled(opt_shadowBlocksAreFilled);
+  }
+
+  return true;
+};
diff --git a/core/workspace.js b/core/workspace.js
index 46661f532..95dc26c00 100644
--- a/core/workspace.js
+++ b/core/workspace.js
@@ -478,6 +478,23 @@ Blockly.Workspace.prototype.getBlockById = function(id) {
   return this.blockDB_[id] || null;
 };
 
+/**
+ * Checks whether all value and statement inputs in the workspace are filled
+ * with blocks.
+ * @param {boolean=} opt_shadowBlocksAreFilled An optional argument controlling
+ *     whether shadow blocks are counted as filled. Defaults to true.
+ * @return {boolean} True if all inputs are filled, false otherwise.
+ */
+Blockly.Workspace.prototype.allInputsFilled = function(opt_shadowBlocksAreFilled) {
+  var blocks = this.getTopBlocks(false);
+  for (var i = 0, block; block = blocks[i]; i++) {
+    if (!block.allInputsFilled(opt_shadowBlocksAreFilled)) {
+      return false;
+    }
+  }
+  return true;
+};
+
 /**
  * Database of all workspaces.
  * @private