improve set-constant, add corresponding helpers and testcases

src/helpers/noop-utils.js

@@ -4,6 +4,12 @@
  */
 export const noopFunc = () => { };
 
+/**
+ * Function return noopFunc
+ * @returns {Function}
+ */
+export const noopCallbackFunc = () => noopFunc;
+
 /**
  * Function returns null
  * @return {null} null
@@ -47,6 +53,14 @@ export const noopArray = () => [];
  */
 export const noopObject = () => ({});
 
+/**
+ * Function throws an error
+ * @throws
+ */
+export const noopThrow = () => {
+    throw new Error();
+};
+
 /**
  * Function returns Promise.reject()
  */

src/scriptlets/set-constant.js

@@ -3,9 +3,11 @@ import {
     logMessage,
     noopArray,
     noopObject,
+    noopCallbackFunc,
     noopFunc,
     trueFunc,
     falseFunc,
+    noopThrow,
     noopPromiseReject,
     noopPromiseResolve,
     getPropertyInChain,
@@ -53,8 +55,10 @@ import {
  *         - `emptyObj` - empty object
  *         - `emptyArr` - empty array
  *         - `noopFunc` - function with empty body
+ *         - `noopCallbackFunc` - function returning noopFunc
  *         - `trueFunc` - function returning true
  *         - `falseFunc` - function returning false
+ *         - `noopThrow` - function throwing an error
  *         - `noopPromiseResolve` - function returning Promise object that is resolved with an empty response
  *         - `noopPromiseReject` - function returning Promise.reject()
  *         - `''` - empty string
@@ -112,10 +116,14 @@ export function setConstant(source, property, value, stack) {
         constantValue = emptyObj;
     } else if (value === 'noopFunc') {
         constantValue = noopFunc;
+    } else if (value === 'noopCallbackFunc') {
+        constantValue = noopCallbackFunc;
     } else if (value === 'trueFunc') {
         constantValue = trueFunc;
     } else if (value === 'falseFunc') {
         constantValue = falseFunc;
+    } else if (value === 'noopThrow') {
+        constantValue = noopThrow;
     } else if (value === 'noopPromiseResolve') {
         constantValue = noopPromiseResolve;
     } else if (value === 'noopPromiseReject') {
@@ -283,8 +291,10 @@ setConstant.injections = [
     noopArray,
     noopObject,
     noopFunc,
+    noopCallbackFunc,
     trueFunc,
     falseFunc,
+    noopThrow,
     noopPromiseReject,
     noopPromiseResolve,
     getPropertyInChain,

tests/helpers/noop.test.js

@@ -1,4 +1,9 @@
-import { noopPromiseResolve } from '../../src/helpers';
+import {
+    noopPromiseResolve,
+    noopCallbackFunc,
+    noopFunc,
+    noopThrow,
+} from '../../src/helpers';
 
 const { test, module } = QUnit;
 const name = 'scriptlets-redirects helpers';
@@ -22,3 +27,14 @@ test('Test noopPromiseResolve for valid response props', async (assert) => {
     assert.ok(Array.isArray(arrBody) && !arrBody.length);
     assert.strictEqual(responseWithType.type, TEST_TYPE);
 });
+
+test('noopCallbackFunc returns noopFunc', async (assert) => {
+    const func = noopCallbackFunc();
+    assert.ok(typeof func === 'function', 'returns function');
+    assert.strictEqual(func.toString(), noopFunc.toString(), 'returns empty function');
+    assert.strictEqual(func(), undefined, 'function returns undefined');
+});
+
+test('noopThrow throws an error', async (assert) => {
+    assert.throws(() => noopThrow(), 'noopThrow throws an error');
+});

tests/scriptlets/set-constant.test.js

@@ -104,6 +104,20 @@ if (!isSupported) {
         assert.strictEqual(window[noopFuncProp](), undefined);
         clearGlobalProps(noopFuncProp);
 
+        // setting constant to noopCallbackFunc;
+        const noopCallbackFuncProp = 'noopCallbackFunc';
+        runScriptletFromTag(noopCallbackFuncProp, 'noopCallbackFunc');
+        const noopFuncCb = window[noopCallbackFuncProp]();
+        assert.ok(typeof noopFuncCb === 'function', 'returns function');
+        assert.strictEqual(noopFuncCb(), undefined, 'function returns undefined');
+        clearGlobalProps(noopCallbackFuncProp);
+
+        // setting constant to noopCallbackFunc;
+        const noopThrowProp = 'noopThrow';
+        runScriptletFromTag(noopThrowProp, 'noopThrow');
+        assert.throws(() => window[noopThrowProp]()(), 'noopThrowProp throws an error');
+        clearGlobalProps(noopThrowProp);
+
         // setting constant to trueFunc;
         const trueFuncProp = 'trueFuncProp';
         runScriptletFromTag(trueFuncProp, 'trueFunc');