feat(calc): Allow to use promises via promiseCalc flag

.babelrc

@@ -11,12 +11,17 @@
 		["transform-es2015-template-literals", { "loose": true }],
 		["transform-es2015-destructuring", { "loose": true }],
 		["transform-es2015-computed-properties", { "loose": true }],
-
-		// the following plugins are used at tests
-		"transform-es2015-classes",
-		"transform-es2015-for-of",
-        ["transform-es2015-spread", {
-          "loose": true
-        }]
-	]
+	],
+	"env": {
+		"test": {
+			"plugins": [
+				"transform-es2015-classes",
+				"transform-es2015-for-of",
+				"babel-plugin-transform-async-to-generator",
+		        ["transform-es2015-spread", {
+		          "loose": true
+		        }]
+			]
+		}
+	}
 }

.eslintrc.js

@@ -6,6 +6,7 @@ module.exports = {
     rules: {
         indent: ['error', 4, { 'SwitchCase': 1 }],
         'no-var': 'error',
+        'no-console': 'error',
         'prefer-rest-params': 0, // arguments work faster
         'no-param-reassign': ["error", { "props": false }],
         'no-underscore-dangle': 0, // for some hacks and array methods underscore prefix/suffix is required

package.json

@@ -6,11 +6,11 @@
   "main": "matreshka.js",
   "scripts": {
     "test": "npm run node-cover && npm run check-coverage && npm run lint",
-    "node-test": "babel-node test/node-test/jasmine.js",
-    "node-cover": "babel-node node_modules/.bin/babel-istanbul cover test/node-test/jasmine.js && cat ./coverage/lcov.info | ./node_modules/coveralls/bin/coveralls.js",
+    "node-test": "BABEL_ENV=test babel-node test/node-test/jasmine.js",
+    "node-cover": "BABEL_ENV=test babel-node node_modules/.bin/babel-istanbul cover test/node-test/jasmine.js && cat ./coverage/lcov.info | ./node_modules/coveralls/bin/coveralls.js",
     "check-coverage": "babel-istanbul check-coverage --lines 95",
     "develop": "CHROME_BIN=chromium-browser karma start test/karma-test/karma.conf.js",
-    "karma-test": "CHROME_BIN=chromium-browser karma start test/karma-test/karma.conf.js --single-run --no-auto-watch",
+    "karma-test": "BABEL_ENV=test CHROME_BIN=chromium-browser karma start test/karma-test/karma.conf.js --single-run --no-auto-watch",
     "karma-libraries-test": "npm run karma-test && npm run karma-test -- --dom-library=jquery-1 && npm run karma-test -- --dom-library=jquery-2 && npm run karma-test -- --dom-library=jquery-3 && npm run karma-test -- --dom-library=zepto",
     "watch": "webpack --config ./webpack.config.js --watch",
     "watch-browser-test": "webpack --config test/webpack-test.config.js --watch",
@@ -25,7 +25,7 @@
     "npm-deploy": "npm run npm-compile && npm run npm-deploy-setup && npm run npm-publish",
     "bundle": "webpack --config ./webpack.config.js",
     "deploy-to-git": "shx rm -rf bundle && deploy-to-git",
-    "bundle-browser-test": "webpack --config test/webpack-test.config.js",
+    "bundle-browser-test": "BABEL_ENV=test webpack --config test/webpack-test.config.js",
     "bundle-deploy-script": "npm run bundle && npm run bundle-browser-test",
     "upgrade": "ncu -u -a && yarn install"
   },
@@ -83,6 +83,7 @@
     "babel-loader": "^6.4.1",
     "babel-plugin-check-es2015-constants": "^6.22.0",
     "babel-plugin-nofn": "0.0.3",
+    "babel-plugin-transform-async-to-generator": "^6.24.1",
     "babel-plugin-transform-es2015-arrow-functions": "^6.22.0",
     "babel-plugin-transform-es2015-block-scoping": "^6.24.1",
     "babel-plugin-transform-es2015-classes": "^6.24.1",

src/calc/_createcalchandler.js

@@ -15,6 +15,7 @@ export default function createCalcHandler({
         const values = [];
         const { protector = {} } = changeEvent;
         const protectKey = target + def.id;
+        const { promiseCalc } = eventOptions;
         const setEventOptions = {
             protector,
             ...eventOptions,
@@ -36,7 +37,20 @@ export default function createCalcHandler({
             values.push(value);
         });
 
-        const targetValue = apply(handler, object, values);
-        set(object, target, targetValue, setEventOptions);
+        let targetValue = apply(handler, object, values);
+
+        if (promiseCalc) {
+            if (!(targetValue instanceof Promise)) {
+                targetValue = Promise.resolve(targetValue);
+            }
+
+            targetValue
+                .then(promiseResult => set(object, target, promiseResult, setEventOptions))
+                .catch((e) => {
+                    throw Error(e);
+                });
+        } else {
+            set(object, target, targetValue, setEventOptions);
+        }
     };
 }

test/browser-test/SpecRunner.html

@@ -10,6 +10,7 @@
   <script src="jasmine-2.4.1/jasmine.js"></script>
   <script src="jasmine-2.4.1/jasmine-html.js"></script>
   <script src="jasmine-2.4.1/boot.js"></script>
+  <script src="es6-promise.min.js"></script>
 </head>
 
 <body>

test/spec/bindings/existence_binder_spec.js

@@ -110,7 +110,6 @@ describe('Existence binder', () => {
 
         for (const item of arr) {
             bindNode(item, 'exists', ':sandbox', existence(), noDebounceFlag);
-            console.log(select(item, ':sandbox').__matreshkaReplacedByNode);
         }
 
         expect(

test/spec/calc_spec.js

@@ -5,6 +5,7 @@ import makeObject from '../helpers/makeobject';
 import createSpy from '../helpers/createspy';
 
 const noDebounceFlag = { debounceCalc: false };
+const delay = duration => new Promise(resolve => setTimeout(resolve, duration));
 
 describe('calc', () => {
     it('adds simple dependency', () => {
@@ -254,4 +255,46 @@ describe('calc', () => {
 
         expect(handler).not.toHaveBeenCalled();
     });
+
+    it('allows to use promises via promiseCalc', async (done) => {
+        const obj = {
+            a: 1,
+            b: 2
+        };
+
+        calc(obj, 'c', ['a', 'b'], (a, b) => new Promise(resolve => setTimeout(() => resolve(a + b), 10)), {
+            promiseCalc: true
+        });
+
+        expect(obj.c).toEqual(undefined);
+        obj.a = 3;
+        await delay(50);
+        expect(obj.c).toEqual(5);
+        obj.b = 3;
+        await delay(50);
+        expect(obj.c).toEqual(6);
+
+        done();
+    });
+
+    it('allows to use non-promises when promiseCalc=true', async (done) => {
+        const obj = {
+            a: 1,
+            b: 2
+        };
+
+        calc(obj, 'c', ['a', 'b'], (a, b) => a + b, {
+            promiseCalc: true
+        });
+
+        expect(obj.c).toEqual(undefined);
+        obj.a = 3;
+        await delay(50);
+        expect(obj.c).toEqual(5);
+        obj.b = 3;
+        await delay(50);
+        expect(obj.c).toEqual(6);
+
+        done();
+    });
 });

yarn.lock

@@ -422,6 +422,16 @@ babel-helper-optimise-call-expression@^6.24.1:
     babel-runtime "^6.22.0"
     babel-types "^6.24.1"
 
+babel-helper-remap-async-to-generator@^6.24.1:
+  version "6.24.1"
+  resolved "https://registry.yarnpkg.com/babel-helper-remap-async-to-generator/-/babel-helper-remap-async-to-generator-6.24.1.tgz#5ec581827ad723fecdd381f1c928390676e4551b"
+  dependencies:
+    babel-helper-function-name "^6.24.1"
+    babel-runtime "^6.22.0"
+    babel-template "^6.24.1"
+    babel-traverse "^6.24.1"
+    babel-types "^6.24.1"
+
 babel-helper-replace-supers@^6.24.1:
   version "6.24.1"
   resolved "https://registry.yarnpkg.com/babel-helper-replace-supers/-/babel-helper-replace-supers-6.24.1.tgz#bf6dbfe43938d17369a213ca8a8bf74b6a90ab1a"
@@ -531,10 +541,22 @@ [email protected]:
     babel-template "^6.3.13"
     better-log "^1.3.1"
 
+babel-plugin-syntax-async-functions@^6.8.0:
+  version "6.13.0"
+  resolved "https://registry.yarnpkg.com/babel-plugin-syntax-async-functions/-/babel-plugin-syntax-async-functions-6.13.0.tgz#cad9cad1191b5ad634bf30ae0872391e0647be95"
+
 babel-plugin-syntax-object-rest-spread@^6.8.0:
   version "6.13.0"
   resolved "https://registry.yarnpkg.com/babel-plugin-syntax-object-rest-spread/-/babel-plugin-syntax-object-rest-spread-6.13.0.tgz#fd6536f2bce13836ffa3a5458c4903a597bb3bf5"
 
+babel-plugin-transform-async-to-generator@^6.24.1:
+  version "6.24.1"
+  resolved "https://registry.yarnpkg.com/babel-plugin-transform-async-to-generator/-/babel-plugin-transform-async-to-generator-6.24.1.tgz#6536e378aff6cb1d5517ac0e40eb3e9fc8d08761"
+  dependencies:
+    babel-helper-remap-async-to-generator "^6.24.1"
+    babel-plugin-syntax-async-functions "^6.8.0"
+    babel-runtime "^6.22.0"
+
 babel-plugin-transform-es2015-arrow-functions@^6.22.0:
   version "6.22.0"
   resolved "https://registry.yarnpkg.com/babel-plugin-transform-es2015-arrow-functions/-/babel-plugin-transform-es2015-arrow-functions-6.22.0.tgz#452692cb711d5f79dc7f85e440ce41b9f244d221"