refactor(std): add std/_util/os.ts module (#8370)

This commit adds "std/_util/os.ts" module which contains
common os detection logic and is browser compatible.

Co-authored-by: Nayeem Rahman <nayeemrmn99@gmail.com>

1 files changed, 1 insertions, 2 deletions

diff --git a/std/fs/copy.ts b/std/fs/copy.ts
index 10bf89186..1bb0a6aff 100644
--- a/std/fs/copy.ts
+++ b/std/fs/copy.ts
@@ -3,8 +3,7 @@ import * as path from "../path/mod.ts";
 import { ensureDir, ensureDirSync } from "./ensure_dir.ts";
 import { getFileInfoType, isSubdir } from "./_util.ts";
 import { assert } from "../_util/assert.ts";
-
-const isWindows = Deno.build.os === "windows";
+import { isWindows } from "../_util/os.ts";
 
 export interface CopyOptions {
   /**