From c0bbcb656425cc936d5701802157b92099cf87fe Mon Sep 17 00:00:00 2001
From: golopot <golopot@gmail.com>
Date: Sat, 13 Jul 2019 11:39:18 +0800
Subject: [PATCH] Change how function overloads are recognized

---
 src/rules/export.js       | 18 +++++++++++-------
 tests/src/rules/export.js | 14 +++-----------
 2 files changed, 14 insertions(+), 18 deletions(-)

diff --git a/src/rules/export.js b/src/rules/export.js
index c9e2cc8824..7739255c5b 100644
--- a/src/rules/export.js
+++ b/src/rules/export.js
@@ -26,15 +26,20 @@ const tsTypePrefix = 'type:'
 
 /**
  * Detect function overloads like:
- * ```js
- * export function foo(a: number) {}
- * export function foo(a: string) {}
+ * ```ts
+ * export function foo(a: number);
+ * export function foo(a: string);
+ * export function foo(a: number|string) { return a; }
  * ```
- * @param {Set<Object>} nodes
+ * @param {Object[]} nodes
  * @returns {boolean}
  */
 function isTypescriptFunctionOverloads(nodes) {
-  return [...nodes].every(node => node.parent.type === 'FunctionDeclaration')
+  return nodes.some(node => node.parent.type === 'TSDeclareFunction') &&
+    nodes.every(node => (
+      node.parent.type === 'TSDeclareFunction' ||
+      node.parent.type === 'FunctionDeclaration'
+    ))
 }
 
 module.exports = {
@@ -47,7 +52,6 @@ module.exports = {
 
   create: function (context) {
     const namespace = new Map([[rootProgram, new Map()]])
-    const isTypescriptFile = /\.ts|\.tsx$/.test(context.getFilename())
 
     function addNamed(name, node, parent, isType) {
       if (!namespace.has(parent)) {
@@ -137,7 +141,7 @@ module.exports = {
           for (let [name, nodes] of named) {
             if (nodes.size <= 1) continue
 
-            if (isTypescriptFile && isTypescriptFunctionOverloads(nodes)) continue
+            if (isTypescriptFunctionOverloads([...nodes])) continue
 
             for (let node of nodes) {
               if (name === 'default') {
diff --git a/tests/src/rules/export.js b/tests/src/rules/export.js
index f0341669e9..70218ebb1c 100644
--- a/tests/src/rules/export.js
+++ b/tests/src/rules/export.js
@@ -149,18 +149,10 @@ context('Typescript', function () {
 
         test(Object.assign({
           code: `
-            export function fff(a: string) {};
-            export function fff(a: number) {};
+            export function fff(a: string);
+            export function fff(a: number);
+            export function fff(a: string|number) {};
           `,
-          filename: 'foo.ts',
-        }, parserConfig)),
-
-        test(Object.assign({
-          code: `
-            export function ggg(a: string) {};
-            export function ggg(a: number) {};
-          `,
-          filename: 'foo.tsx',
         }, parserConfig)),
 
         // namespace