From bccdab25a19039ea8952f2b4e43c5f4d0b8f10d6 Mon Sep 17 00:00:00 2001
From: Joel Einbinder <joel.einbinder@gmail.com>
Date: Tue, 31 Mar 2020 03:59:25 -0700
Subject: [PATCH] fix(types): correctly infer type in $eval and $$eval

---
 utils/generate_types/overrides.d.ts | 12 ++++++------
 utils/generate_types/test/test.ts   |  9 ++++++++-
 2 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/utils/generate_types/overrides.d.ts b/utils/generate_types/overrides.d.ts
index 3ce6f90f62708..a923f78c11439 100644
--- a/utils/generate_types/overrides.d.ts
+++ b/utils/generate_types/overrides.d.ts
@@ -56,12 +56,12 @@ export interface Page {
 
   $eval<K extends keyof HTMLElementTagNameMap, R, Arg>(selector: K, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K], Arg, R>, arg: Arg): Promise<R>;
   $eval<R, Arg>(selector: string, pageFunction: PageFunctionOn<HTMLOrSVGElement, Arg, R>, arg: Arg): Promise<R>;
-  $eval<K extends keyof HTMLElementTagNameMap, R>(selector: string, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K], void, R>, arg?: any): Promise<R>;
+  $eval<K extends keyof HTMLElementTagNameMap, R>(selector: K, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K], void, R>, arg?: any): Promise<R>;
   $eval<R>(selector: string, pageFunction: PageFunctionOn<HTMLOrSVGElement, void, R>, arg?: any): Promise<R>;
 
   $$eval<K extends keyof HTMLElementTagNameMap, R, Arg>(selector: K, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K][], Arg, R>, arg: Arg): Promise<R>;
   $$eval<R, Arg>(selector: string, pageFunction: PageFunctionOn<HTMLOrSVGElement[], Arg, R>, arg: Arg): Promise<R>;
-  $$eval<K extends keyof HTMLElementTagNameMap, R>(selector: string, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K][], void, R>, arg?: any): Promise<R>;
+  $$eval<K extends keyof HTMLElementTagNameMap, R>(selector: K, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K][], void, R>, arg?: any): Promise<R>;
   $$eval<R>(selector: string, pageFunction: PageFunctionOn<HTMLOrSVGElement[], void, R>, arg?: any): Promise<R>;
 
   waitForFunction<R, Arg>(pageFunction: PageFunction<Arg, R>, arg: Arg, options?: PageWaitForFunctionOptions): Promise<SmartHandle<R>>;
@@ -88,12 +88,12 @@ export interface Frame {
 
   $eval<K extends keyof HTMLElementTagNameMap, R, Arg>(selector: K, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K], Arg, R>, arg: Arg): Promise<R>;
   $eval<R, Arg>(selector: string, pageFunction: PageFunctionOn<HTMLOrSVGElement, Arg, R>, arg: Arg): Promise<R>;
-  $eval<K extends keyof HTMLElementTagNameMap, R>(selector: string, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K], void, R>, arg?: any): Promise<R>;
+  $eval<K extends keyof HTMLElementTagNameMap, R>(selector: K, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K], void, R>, arg?: any): Promise<R>;
   $eval<R>(selector: string, pageFunction: PageFunctionOn<HTMLOrSVGElement, void, R>, arg?: any): Promise<R>;
 
   $$eval<K extends keyof HTMLElementTagNameMap, R, Arg>(selector: K, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K][], Arg, R>, arg: Arg): Promise<R>;
   $$eval<R, Arg>(selector: string, pageFunction: PageFunctionOn<HTMLOrSVGElement[], Arg, R>, arg: Arg): Promise<R>;
-  $$eval<K extends keyof HTMLElementTagNameMap, R>(selector: string, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K][], void, R>, arg?: any): Promise<R>;
+  $$eval<K extends keyof HTMLElementTagNameMap, R>(selector: K, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K][], void, R>, arg?: any): Promise<R>;
   $$eval<R>(selector: string, pageFunction: PageFunctionOn<HTMLOrSVGElement[], void, R>, arg?: any): Promise<R>;
 
   waitForFunction<R, Arg>(pageFunction: PageFunction<Arg, R>, arg: Arg, options?: PageWaitForFunctionOptions): Promise<SmartHandle<R>>;
@@ -133,12 +133,12 @@ export interface ElementHandle<T=Node> extends JSHandle<T> {
 
   $eval<K extends keyof HTMLElementTagNameMap, R, Arg>(selector: K, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K], Arg, R>, arg: Arg): Promise<R>;
   $eval<R, Arg>(selector: string, pageFunction: PageFunctionOn<HTMLOrSVGElement, Arg, R>, arg: Arg): Promise<R>;
-  $eval<K extends keyof HTMLElementTagNameMap, R>(selector: string, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K], void, R>, arg?: any): Promise<R>;
+  $eval<K extends keyof HTMLElementTagNameMap, R>(selector: K, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K], void, R>, arg?: any): Promise<R>;
   $eval<R>(selector: string, pageFunction: PageFunctionOn<HTMLOrSVGElement, void, R>, arg?: any): Promise<R>;
 
   $$eval<K extends keyof HTMLElementTagNameMap, R, Arg>(selector: K, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K][], Arg, R>, arg: Arg): Promise<R>;
   $$eval<R, Arg>(selector: string, pageFunction: PageFunctionOn<HTMLOrSVGElement[], Arg, R>, arg: Arg): Promise<R>;
-  $$eval<K extends keyof HTMLElementTagNameMap, R>(selector: string, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K][], void, R>, arg?: any): Promise<R>;
+  $$eval<K extends keyof HTMLElementTagNameMap, R>(selector: K, pageFunction: PageFunctionOn<HTMLElementTagNameMap[K][], void, R>, arg?: any): Promise<R>;
   $$eval<R>(selector: string, pageFunction: PageFunctionOn<HTMLOrSVGElement[], void, R>, arg?: any): Promise<R>;
 }
 
diff --git a/utils/generate_types/test/test.ts b/utils/generate_types/test/test.ts
index 90804708687dd..b040d60a8d5ae 100644
--- a/utils/generate_types/test/test.ts
+++ b/utils/generate_types/test/test.ts
@@ -286,7 +286,14 @@ playwright.chromium.launch().then(async browser => {
     console.log(elements.map(x => x)[0].textContent);
     return elements[3].innerHTML;
   });
-
+  {
+    const value = await page.$eval('input', i => i.disabled);
+    const assertion: AssertType<boolean, typeof value> = true;
+  }
+  {
+    const value = await page.$$eval('input', i => i[0].defaultValue);
+    const assertion: AssertType<string, typeof value> = true;
+  }
   browser.close();
 })();