Add ability to unit test by permissions.

js/test_util.ts

@@ -0,0 +1,70 @@
+// Copyright 2018 the Deno authors. All rights reserved. MIT license.
+//
+// We want to test many ops in deno which have different behavior depending on
+// the permissions set. These tests can specify which permissions they expect,
+// which appends a special string like "permW1N0" to the end of the test name.
+// Here we run several copies of deno with different permissions, filtering the
+// tests by the special string. permW0N0 means allow-write but not allow-net.
+// See tools/unit_tests.py for more details.
+
+import * as deno from "deno";
+import * as testing from "./testing/testing.ts";
+export { assert, assertEqual } from "./testing/testing.ts";
+
+// testing.setFilter must be run before any tests are defined.
+const permFilter = deno.argv[1];
+permFromString(permFilter);
+testing.setFilter(permFilter);
+
+interface DenoPermissions {
+  write?: boolean;
+  net?: boolean;
+}
+
+function permToString(perms: DenoPermissions): string {
+  const w = perms.write ? 1 : 0;
+  const n = perms.net ? 1 : 0;
+  return `permW${w}N${n}`;
+}
+
+function permFromString(s: string): DenoPermissions {
+  const re = /^permW([01])N([01])$/;
+  const found = s.match(re);
+  if (!found) {
+    throw Error("Not a permission string");
+  }
+  return {
+    write: Boolean(Number(found[1])),
+    net: Boolean(Number(found[2]))
+  };
+}
+
+export function testPerm(perms: DenoPermissions, fn: testing.TestFunction) {
+  const name = `${fn.name}_${permToString(perms)}`;
+  testing.test({ fn, name });
+}
+
+export function test(fn: testing.TestFunction) {
+  testPerm({ write: false, net: false }, fn);
+}
+
+test(function permSerialization() {
+  for (let write of [true, false]) {
+    for (let net of [true, false]) {
+      let perms: DenoPermissions = { write, net };
+      testing.assertEqual(perms, permFromString(permToString(perms)));
+    }
+  }
+});
+
+// To better catch internal errors, permFromString should throw if it gets an
+// invalid permission string.
+test(function permFromStringThrows() {
+  let threw = false;
+  try {
+    permFromString("bad");
+  } catch (e) {
+    threw = true;
+  }
+  testing.assert(threw);
+});