BREAKING: Include limited metadata in 'DirEntry' objects (#4941)

This change is to prevent needed a separate stat syscall for each file
when using readdir.

For consistency, this PR also modifies std's `WalkEntry` interface to
extend `DirEntry` with an additional `path` field.

4 files changed, 14 insertions, 20 deletions

diff --git a/cli/js/lib.deno.ns.d.ts b/cli/js/lib.deno.ns.d.ts
index e58ec0b55..d7d885b5b 100644
--- a/cli/js/lib.deno.ns.d.ts
+++ b/cli/js/lib.deno.ns.d.ts
@@ -1386,8 +1386,11 @@ declare namespace Deno {
    * Requires `allow-read` permission. */
   export function realpath(path: string): Promise<string>;
 
-  export interface DirEntry extends FileInfo {
+  export interface DirEntry {
     name: string;
+    isFile: boolean;
+    isDirectory: boolean;
+    isSymlink: boolean;
   }
 
   /** Synchronously reads the directory given by `path` and returns an iterable
diff --git a/cli/js/ops/fs/read_dir.ts b/cli/js/ops/fs/read_dir.ts
index 29b8676ef..7d65fed48 100644
--- a/cli/js/ops/fs/read_dir.ts
+++ b/cli/js/ops/fs/read_dir.ts
@@ -1,21 +1,19 @@
 // Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
 import { sendSync, sendAsync } from "../dispatch_json.ts";
-import { FileInfo, StatResponse, parseFileInfo } from "./stat.ts";
 
-export interface DirEntry extends FileInfo {
+export interface DirEntry {
   name: string;
+  isFile: boolean;
+  isDirectory: boolean;
+  isSymlink: boolean;
 }
 
 interface ReadDirResponse {
-  entries: StatResponse[];
+  entries: DirEntry[];
 }
 
 function res(response: ReadDirResponse): DirEntry[] {
-  return response.entries.map(
-    (statRes: StatResponse): DirEntry => {
-      return { ...parseFileInfo(statRes), name: statRes.name! };
-    }
-  );
+  return response.entries;
 }
 
 export function readdirSync(path: string): Iterable<DirEntry> {
diff --git a/cli/js/ops/fs/stat.ts b/cli/js/ops/fs/stat.ts
index c3563a8c4..e8fd28218 100644
--- a/cli/js/ops/fs/stat.ts
+++ b/cli/js/ops/fs/stat.ts
@@ -29,8 +29,6 @@ export interface StatResponse {
   mtime: number | null;
   atime: number | null;
   birthtime: number | null;
-  // Null for stat(), but exists for readdir().
-  name: string | null;
   // Unix only members
   dev: number;
   ino: number;
diff --git a/cli/js/tests/read_dir_test.ts b/cli/js/tests/read_dir_test.ts
index 2c7f42103..f1c7ea121 100644
--- a/cli/js/tests/read_dir_test.ts
+++ b/cli/js/tests/read_dir_test.ts
@@ -4,19 +4,14 @@ import { unitTest, assert, assertEquals } from "./test_util.ts";
 function assertSameContent(files: Deno.DirEntry[]): void {
   let counter = 0;
 
-  for (const file of files) {
-    if (file.name === "subdir") {
-      assert(file.isDirectory);
-      counter++;
-    }
-
-    if (file.name === "002_hello.ts") {
-      assertEquals(file.mode!, Deno.statSync(`cli/tests/${file.name}`).mode!);
+  for (const entry of files) {
+    if (entry.name === "subdir") {
+      assert(entry.isDirectory);
       counter++;
     }
   }
 
-  assertEquals(counter, 2);
+  assertEquals(counter, 1);
 }
 
 unitTest({ perms: { read: true } }, function readdirSyncSuccess(): void {