BREAKING: Map-like interface for Deno.env (#4942)

3 files changed, 46 insertions, 51 deletions

diff --git a/cli/js/lib.deno.ns.d.ts b/cli/js/lib.deno.ns.d.ts
index edc9668e7..e58ec0b55 100644
--- a/cli/js/lib.deno.ns.d.ts
+++ b/cli/js/lib.deno.ns.d.ts
@@ -116,29 +116,35 @@ declare namespace Deno {
    */
   export function exit(code?: number): never;
 
-  /** Returns a snapshot of the environment variables at invocation. Changing a
-   * property in the object will set that variable in the environment for the
-   * process. The environment object will only accept `string`s as values.
-   *
-   *       const myEnv = Deno.env();
-   *       console.log(myEnv.SHELL);
-   *       myEnv.TEST_VAR = "HELLO";
-   *       const newEnv = Deno.env();
-   *       console.log(myEnv.TEST_VAR === newEnv.TEST_VAR);  // outputs "true"
-   *
-   * Requires `allow-env` permission. */
-  export function env(): {
-    [index: string]: string;
-  };
+  export const env: {
+    /** Retrieve the value of an environment variable. Returns undefined if that
+     * key doesn't exist.
+     *
+     *       console.log(Deno.env.get("HOME"));  // e.g. outputs "/home/alice"
+     *       console.log(Deno.env.get("MADE_UP_VAR"));  // outputs "Undefined"
+     *
+     * Requires `allow-env` permission. */
+    get(key: string): string | undefined;
 
-  /** Retrieve the value of an environment variable. Returns undefined if that
-   * key doesn't exist.
-   *
-   *       console.log(Deno.env("HOME"));  // e.g. outputs "/home/alice"
-   *       console.log(Deno.env("MADE_UP_VAR"));  // outputs "Undefined"
-   *
-   * Requires `allow-env` permission. */
-  export function env(key: string): string | undefined;
+    /** Set the value of an environment variable.
+     *
+     *       Deno.env.set("SOME_VAR", "Value"));
+     *       Deno.env.get("SOME_VAR");  // outputs "Value"
+     *
+     * Requires `allow-env` permission. */
+    set(key: string, value: string): void;
+
+    /** Returns a snapshot of the environment variables at invocation.
+     *
+     *       Deno.env.set("TEST_VAR", "A");
+     *       const myEnv = Deno.env.toObject();
+     *       console.log(myEnv.SHELL);
+     *       Deno.env.set("TEST_VAR", "B");
+     *       console.log(myEnv.TEST_VAR);  // outputs "A"
+     *
+     * Requires `allow-env` permission. */
+    toObject(): { [index: string]: string };
+  };
 
   /** **UNSTABLE** */
   export type DirKind =
diff --git a/cli/js/ops/os.ts b/cli/js/ops/os.ts
index e01718c8c..30aa6d0d4 100644
--- a/cli/js/ops/os.ts
+++ b/cli/js/ops/os.ts
@@ -27,22 +27,13 @@ function getEnv(key: string): string | undefined {
   return sendSync("op_get_env", { key })[0];
 }
 
-export function env(): { [index: string]: string };
-export function env(key: string): string | undefined;
-export function env(
-  key?: string
-): { [index: string]: string } | string | undefined {
-  if (key) {
-    return getEnv(key);
-  }
-  const env = sendSync("op_env");
-  return new Proxy(env, {
-    set(obj, prop: string, value: string): boolean {
-      setEnv(prop, value);
-      return Reflect.set(obj, prop, value);
-    },
-  });
-}
+export const env = {
+  get: getEnv,
+  toObject(): { [key: string]: string } {
+    return sendSync("op_env");
+  },
+  set: setEnv,
+};
 
 type DirKind =
   | "home"
diff --git a/cli/js/tests/os_test.ts b/cli/js/tests/os_test.ts
index 58dcd1bc5..a44b69e7d 100644
--- a/cli/js/tests/os_test.ts
+++ b/cli/js/tests/os_test.ts
@@ -8,24 +8,22 @@ import {
 } from "./test_util.ts";
 
 unitTest({ perms: { env: true } }, function envSuccess(): void {
-  const env = Deno.env();
-  assert(env !== null);
-  // eslint-disable-next-line @typescript-eslint/camelcase
-  env.test_var = "Hello World";
-  const newEnv = Deno.env();
-  assertEquals(env.test_var, newEnv.test_var);
-  assertEquals(Deno.env("test_var"), env.test_var);
+  Deno.env.set("TEST_VAR", "A");
+  const env = Deno.env.toObject();
+  Deno.env.set("TEST_VAR", "B");
+  assertEquals(env["TEST_VAR"], "A");
+  assertNotEquals(Deno.env.get("TEST_VAR"), env["TEST_VAR"]);
 });
 
 unitTest({ perms: { env: true } }, function envNotFound(): void {
-  const r = Deno.env("env_var_does_not_exist!");
+  const r = Deno.env.get("env_var_does_not_exist!");
   assertEquals(r, undefined);
 });
 
 unitTest(function envPermissionDenied1(): void {
   let err;
   try {
-    Deno.env();
+    Deno.env.toObject();
   } catch (e) {
     err = e;
   }
@@ -37,7 +35,7 @@ unitTest(function envPermissionDenied1(): void {
 unitTest(function envPermissionDenied2(): void {
   let err;
   try {
-    Deno.env("PATH");
+    Deno.env.get("PATH");
   } catch (e) {
     err = e;
   }
@@ -62,7 +60,7 @@ unitTest(
     ): Promise<void> => {
       const src = `
       console.log(
-        ${JSON.stringify(Object.keys(expectedEnv))}.map(k => Deno.env(k))
+        ${JSON.stringify(Object.keys(expectedEnv))}.map(k => Deno.env.get(k))
       )`;
       const proc = Deno.run({
         cmd: [Deno.execPath(), "eval", src],
@@ -79,8 +77,8 @@ unitTest(
       proc.close();
     };
 
-    assertEquals(Deno.env("path"), Deno.env("PATH"));
-    assertEquals(Deno.env("Path"), Deno.env("PATH"));
+    assertEquals(Deno.env.get("path"), Deno.env.get("PATH"));
+    assertEquals(Deno.env.get("Path"), Deno.env.get("PATH"));
 
     // Check 'foo', 'Foo' and 'Foo' are case folded.
     await checkChildEnv({ foo: "X" }, { foo: "X", Foo: "X", FOO: "X" });