Fix false positives for arrow return in vue/valid-next-tick rule (#1686)

Author: ota-meshi

lib/rules/valid-next-tick.js

@@ -76,6 +76,13 @@ function isAwaitedPromise(callExpression) {
     // cases like `return nextTick()`
     return true
   }
+  if (
+    callExpression.parent.type === 'ArrowFunctionExpression' &&
+    callExpression.parent.body === callExpression
+  ) {
+    // cases like `() => nextTick()`
+    return true
+  }
 
   if (
     callExpression.parent.type === 'MemberExpression' &&

tests/lib/rules/valid-next-tick.js

@@ -113,6 +113,22 @@ tester.run('valid-next-tick', rule, {
           return this.$nextTick();
         }
       }</script>`
+    },
+
+    {
+      filename: 'test.vue',
+      code: `<script>;
+      export default {
+        methods: {
+          fn1 () {
+            return this.$nextTick()
+          },
+          fn2 () {
+            return this.$nextTick()
+              .then(() => this.$nextTick())
+          },
+        }
+      }</script>`
     }
   ],
   invalid: [