Merge pull request #154 from canjs/debugger-key-lookup

adding `debugger` as a reserved scope key

scope-key-data.js

@@ -10,6 +10,7 @@ var CIDSet = require("can-cid/set/set");
 var makeComputeLike = require("./make-compute-like");
 var canReflectDeps = require('can-reflect-dependencies');
 var valueEventBindings = require("can-event-queue/value/value");
+var stacheHelpers = require('can-stache-helpers');
 
 var dispatchSymbol = canSymbol.for("can.dispatch");
 
@@ -64,6 +65,19 @@ var ScopeKeyData = function(scope, key, options){
 	this.read = this.read.bind(this);
 	this.dispatch = this.dispatch.bind(this);
 
+	// special case debugger helper so that it is called with helperOtions
+	// when you do {{debugger}} as it already is with {{debugger()}}
+	if (key === "debugger") {
+		// prevent "Unable to find key" warning
+		this.startingScope = { _context: stacheHelpers };
+
+		this.read = function() {
+			var helperOptions = { scope: scope };
+			var debuggerHelper = stacheHelpers["debugger"];
+			return debuggerHelper(helperOptions);
+		};
+	}
+
 	//!steal-remove-start
 	Object.defineProperty(this.read, "name", {
 		value: "{{" + this.key + "}}::ScopeKeyData.read",

test/scope-test.js

@@ -1132,3 +1132,17 @@ QUnit.test("functions have correct `thisArg` so they can be called even with `pr
 	QUnit.equal(parentFunc.value, func, "parentFunc.value === func");
 	QUnit.equal(parentFunc.thisArg, parentData, "rootFunc.thisArg === parentData");
 });
+
+QUnit.test("debugger is a reserved scope key for calling debugger helper", function() {
+	var scope = new Scope({ name: "Kevin" });
+
+	var debuggerHelper = function(options) {
+		return options.scope.read("name").value;
+	};
+	canStacheHelpers["debugger"] = debuggerHelper;
+
+	var debuggerScopeKey = scope.compute("debugger");
+	QUnit.equal(canReflect.getValue(debuggerScopeKey), "Kevin", "debugger called with correct helper options");
+
+	delete canStacheHelpers["debugger"];
+});