Fix export without declaration. Fixes #393

Author: tmcw

lib/infer/kind.js

@@ -50,7 +50,10 @@ module.exports = function () {
           // This behavior is in need of fixing https://github.com/documentationjs/documentation/issues/351
           findKind(path.node.declarations[0].init);
         }
-      } else if (t.isExportNamedDeclaration(path)) {
+      } else if (t.isExportNamedDeclaration(path) && path.node.declaration) {
+        // && makes sure that
+        // export { foo } from bar;
+        // doesn't check for a non-existent declaration type
         if (path.node.declaration.kind === 'const') {
           comment.kind = 'constant';
         }

test/fixture/es6-import.output.json

@@ -50,6 +50,10 @@ This function returns the number one.
 
 Returns **[Number](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number)** numberone
 
+# execute
+
+This is re-exported
+
 # foo
 
 This is an async method

test/fixture/es6-import.output.md

@@ -865,6 +865,51 @@
         }
       ]
     },
+    {
+      "depth": 1,
+      "type": "heading",
+      "children": [
+        {
+          "type": "text",
+          "value": "execute"
+        }
+      ]
+    },
+    {
+      "type": "paragraph",
+      "children": [
+        {
+          "type": "text",
+          "value": "This is re-exported",
+          "position": {
+            "start": {
+              "line": 1,
+              "column": 1,
+              "offset": 0
+            },
+            "end": {
+              "line": 1,
+              "column": 20,
+              "offset": 19
+            },
+            "indent": []
+          }
+        }
+      ],
+      "position": {
+        "start": {
+          "line": 1,
+          "column": 1,
+          "offset": 0
+        },
+        "end": {
+          "line": 1,
+          "column": 20,
+          "offset": 19
+        },
+        "indent": []
+      }
+    },
     {
       "depth": 1,
       "type": "heading",

test/fixture/es6-import.output.md.json

@@ -117,3 +117,8 @@ function iAmPublic() { }
  * @access private
  */
 function iAmAccessPrivate() { }
+
+/**
+ * This is re-exported
+ */
+export { execute } from 'external-module';

test/fixture/es6.input.js

@@ -50,6 +50,10 @@ This function returns the number one.
 
 Returns **[Number](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number)** numberone
 
+# execute
+
+This is re-exported
+
 # foo
 
 This is an async method

test/fixture/es6.output.json

@@ -865,6 +865,51 @@
         }
       ]
     },
+    {
+      "depth": 1,
+      "type": "heading",
+      "children": [
+        {
+          "type": "text",
+          "value": "execute"
+        }
+      ]
+    },
+    {
+      "type": "paragraph",
+      "children": [
+        {
+          "type": "text",
+          "value": "This is re-exported",
+          "position": {
+            "start": {
+              "line": 1,
+              "column": 1,
+              "offset": 0
+            },
+            "end": {
+              "line": 1,
+              "column": 20,
+              "offset": 19
+            },
+            "indent": []
+          }
+        }
+      ],
+      "position": {
+        "start": {
+          "line": 1,
+          "column": 1,
+          "offset": 0
+        },
+        "end": {
+          "line": 1,
+          "column": 20,
+          "offset": 19
+        },
+        "indent": []
+      }
+    },
     {
       "depth": 1,
       "type": "heading",