test: add unit tests for jest-snapshot-plugin

Author: Tidyzq

package.json

@@ -55,6 +55,7 @@
     "karma-mocha": "^1.3.0",
     "karma-webpack": "^3.0.5",
     "mocha": "^5.2.0",
+    "pretty-format": "^26.0.1",
     "webpack": "^4.41.2",
     "webpack-cli": "^3.3.10"
   },

test/unit/jest-snapshot-plugin.test.js

@@ -0,0 +1,41 @@
+const prettyFormat = require('pretty-format')
+const snapshotPlugin = require('../../src/jest-snapshot-plugin')
+
+const testSymbol =
+  typeof Symbol === 'function' && Symbol.for
+      ? Symbol.for('j-component.json')
+      : 0xd846fe
+
+test('snapshot', () => {
+    const str = prettyFormat(
+        {
+            $$typeof: testSymbol,
+            tagName: 'view',
+            attrs: [{name: 'class', value: 'weui'}],
+            event: {
+                tap: {
+                    handler: 'onTap',
+                    id: 0,
+                    isCapture: true,
+                    isCatch: false,
+                    isMutated: true,
+                    name: 'tap',
+                },
+            },
+            children: [
+                'hello ',
+                {
+                    $$typeof: testSymbol,
+                    tagName: 'view',
+                    attrs: [],
+                    event: {},
+                    children: [],
+                },
+            ],
+        },
+        {plugins: [snapshotPlugin]}
+    )
+    expect(str).toEqual(
+        '<view\n  class="weui"\n  capture-mut-bind:tap="onTap"\n>\n  hello \n  <view />\n</view>'
+    )
+})