Avoid crash on block-arrow components with hoc wrapper (#9)

* add test to check crash on block-arrow components with hoc wrapper

* avoid crash on block-arrow components with hoc wrapper

Author: graingert

src/index.js

@@ -88,14 +88,19 @@ export default ({ types: t }: { types: BabelTypes }): Visitor => ({
         return
       }
 
-      // Ignore the `if` since I can't come up with a test case to satisfy it.
-      /* istanbul ignore if */
-      if ( !variable ) {
+      const name = (() => {
+        try {
+          return variable.get('id.name').node
+        } catch (errr) {
+          return undefined
+        }
+      })()
+
+      if ( name == null ) {
         return
       }
 
       const statement = variable.getStatementParent()
-      const { node: name } = variable.get('id.name')
 
       // check to make sure we don't set displayName when already set
       if ( isDisplayNameSet(statement, name) ) {

test/__snapshots__/index.js.snap

@@ -25,6 +25,26 @@ App.displayName = \'App\';
 exports.default = App;"
 `;
 
+exports[`does not crash on block-arrow components with hoc wrapper 1`] = `
+"\'use strict\';
+
+Object.defineProperty(exports, \"__esModule\", {
+  value: true
+});
+
+var _react = require(\'react\');
+
+var _react2 = _interopRequireDefault(_react);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+exports.default = function () {
+  return fn(function (survey) {
+    return _react2.default.createElement(\'div\', null);
+  });
+};"
+`;
+
 exports[`ignores default function block when no return statement 1`] = `
 "\'use strict\';
 

test/fixtures/export-default-hoc-block-arrow/App.js

@@ -0,0 +1,5 @@
+import React from 'react';
+
+export default () => fn(survey => {
+  return <div />;
+});

test/index.js

@@ -162,3 +162,9 @@ test(
   snapshotMacro,
   'ignore-jsx-expression-blocks',
 )
+
+test(
+  'does not crash on block-arrow components with hoc wrapper',
+  snapshotMacro,
+  'export-default-hoc-block-arrow',
+)