Allow inspection and revocation of permissions (#1875)

js/permissions_test.ts

@@ -0,0 +1,22 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+import { testPerm, assert, assertEqual } from "./test_util.ts";
+import { Permission } from "deno";
+
+const knownPermissions: Permission[] = ["run", "read", "write", "net", "env"];
+
+for (let grant of knownPermissions) {
+  testPerm({ [grant]: true }, function envGranted() {
+    const perms = Deno.permissions();
+    assert(perms !== null);
+    for (const perm in perms) {
+      assertEqual(perms[perm], perm === grant);
+    }
+
+    Deno.revokePermission(grant);
+
+    const revoked = Deno.permissions();
+    for (const perm in revoked) {
+      assertEqual(revoked[perm], false);
+    }
+  });
+}