[enzyme-adapter-utils] [new] add getMaskedContext

enzymejs · Jan 8, 2019 · 30749f6 · 30749f6
1 parent a325b81
commit 30749f6
Show file tree

Hide file tree

Showing 3 changed files with 42 additions and 0 deletions.
diff --git a/packages/enzyme-adapter-utils/package.json b/packages/enzyme-adapter-utils/package.json
@@ -36,6 +36,7 @@
   "dependencies": {
     "function.prototype.name": "^1.1.0",
     "object.assign": "^4.1.0",
+    "object.fromentries": "^2.0.0",
     "prop-types": "^15.6.2",
     "semver": "^5.6.0"
   },

diff --git a/packages/enzyme-adapter-utils/src/Utils.js b/packages/enzyme-adapter-utils/src/Utils.js
@@ -1,4 +1,5 @@
 import functionName from 'function.prototype.name';
+import fromEntries from 'object.fromentries';
 import createMountWrapper from './createMountWrapper';
 import createRenderWrapper from './createRenderWrapper';
 import wrap from './wrapWithSimpleWrapper';
@@ -279,3 +280,10 @@ export function simulateError(
 
   componentDidCatch.call(catchingInstance, error, { componentStack });
 }
+
+export function getMaskedContext(contextTypes, unmaskedContext) {
+  if (!contextTypes || !unmaskedContext) {
+    return {};
+  }
+  return fromEntries(Object.keys(contextTypes).map(key => [key, unmaskedContext[key]]));
+}
diff --git a/packages/enzyme-test-suite/test/adapter-utils-spec.jsx b/packages/enzyme-test-suite/test/adapter-utils-spec.jsx
@@ -3,6 +3,7 @@ import { expect } from 'chai';
 import {
   displayNameOfNode,
   ensureKeyOrUndefined,
+  getMaskedContext,
 } from 'enzyme-adapter-utils';
 
 import './_helpers/setupAdapters';
@@ -82,4 +83,36 @@ describe('enzyme-adapter-utils', () => {
       });
     });
   });
+
+  describe('getMaskedContext', () => {
+    const contextTypes = {
+      a() {},
+      c() {},
+    };
+    const unmaskedContext = {
+      a: 1,
+      b: 2,
+      c: 3,
+    };
+    const falsies = [undefined, null, false, '', NaN, 0];
+
+    it('returns an empty object with falsy `contextTypes`', () => {
+      falsies.forEach((falsy) => {
+        expect(getMaskedContext(falsy, unmaskedContext)).to.eql({});
+      });
+    });
+
+    it('returns an empty object with falsy `unmaskedContext`', () => {
+      falsies.forEach((falsy) => {
+        expect(getMaskedContext(contextTypes, falsy)).to.eql({});
+      });
+    });
+
+    it('filters `unmaskedContext` down to `contextTypes`', () => {
+      expect(getMaskedContext(contextTypes, unmaskedContext)).to.eql({
+        a: unmaskedContext.a,
+        c: unmaskedContext.c,
+      });
+    });
+  });
 });