From e5b751723670a36a6c7903c2009460576a7af6a5 Mon Sep 17 00:00:00 2001
From: Christine Abernathy <ca.abernathy@fb.com>
Date: Wed, 22 Jun 2016 07:00:29 -0700
Subject: [PATCH] Handle optional param types when parsing jsdoc format

---
 src/utils/__tests__/parseJsDoc-test.js | 16 ++++++++++++++++
 src/utils/parseJsDoc.js                | 11 ++++++++++-
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/src/utils/__tests__/parseJsDoc-test.js b/src/utils/__tests__/parseJsDoc-test.js
index 36d02a7dbaf..44afcfc0ffe 100644
--- a/src/utils/__tests__/parseJsDoc-test.js
+++ b/src/utils/__tests__/parseJsDoc-test.js
@@ -64,6 +64,22 @@ describe('parseJsDoc', () => {
       });
     });
 
+    it('extracts jsdoc optional', () => {
+      const docblock = `
+        @param {string=} bar
+      `;
+      expect(parseJsDoc(docblock)).toEqual({
+        description: null,
+        returns: null,
+        params: [{
+          name: 'bar',
+          type: {name: 'string'},
+          description: null,
+          optional: true,
+        }],
+      });
+    });
+
     describe('returns', () => {
 
       it('returns null if return is not documented', () => {
diff --git a/src/utils/parseJsDoc.js b/src/utils/parseJsDoc.js
index 9b7ebbae731..5e825e0bccb 100644
--- a/src/utils/parseJsDoc.js
+++ b/src/utils/parseJsDoc.js
@@ -17,6 +17,7 @@ type JsDoc = {
     name: string;
     description: ?string;
     type: ?{name: string};
+    optional?: boolean;
   }];
   returns: ?{
     description: ?string;
@@ -28,7 +29,14 @@ function getType(tag) {
   if (!tag.type) {
     return null;
   }
-  return {name: tag.type.name};
+  return {name: tag.type.name ? tag.type.name : tag.type.expression.name};
+}
+
+function getOptional(tag) {
+  if (tag.type && tag.type.type && tag.type.type === 'OptionalType') {
+    return true;
+  }
+  return;
 }
 
 // Add jsdoc @return description.
@@ -57,6 +65,7 @@ function getParamsJsDoc(jsDoc) {
         name: tag.name,
         description: tag.description,
         type: getType(tag),
+        optional: getOptional(tag),
       };
     });
 }