deno/cli/tests/unit/read_text_file_test.ts

import {
  unitTest,
  assert,
  assertEquals,
  assertThrows,
  assertThrowsAsync,
  pathToAbsoluteFileUrl,
} from "./test_util.ts";

unitTest({ perms: { read: true } }, function readTextFileSyncSuccess(): void {
  const data = Deno.readTextFileSync("cli/tests/fixture.json");
  assert(data.length > 0);
  const pkg = JSON.parse(data);
  assertEquals(pkg.name, "deno");
});

unitTest({ perms: { read: true } }, function readTextFileSyncByUrl(): void {
  const data = Deno.readTextFileSync(
    pathToAbsoluteFileUrl("cli/tests/fixture.json"),
  );
  assert(data.length > 0);
  const pkg = JSON.parse(data);
  assertEquals(pkg.name, "deno");
});

unitTest({ perms: { read: false } }, function readTextFileSyncPerm(): void {
  assertThrows(() => {
    Deno.readTextFileSync("cli/tests/fixture.json");
  }, Deno.errors.PermissionDenied);
});

unitTest({ perms: { read: true } }, function readTextFileSyncNotFound(): void {
  assertThrows(() => {
    Deno.readTextFileSync("bad_filename");
  }, Deno.errors.NotFound);
});

unitTest(
  { perms: { read: true } },
  async function readTextFileSuccess(): Promise<void> {
    const data = await Deno.readTextFile("cli/tests/fixture.json");
    assert(data.length > 0);
    const pkg = JSON.parse(data);
    assertEquals(pkg.name, "deno");
  },
);

unitTest({ perms: { read: true } }, async function readTextFileByUrl(): Promise<
  void
> {
  const data = await Deno.readTextFile(
    pathToAbsoluteFileUrl("cli/tests/fixture.json"),
  );
  assert(data.length > 0);
  const pkg = JSON.parse(data);
  assertEquals(pkg.name, "deno");
});

unitTest({ perms: { read: false } }, async function readTextFilePerm(): Promise<
  void
> {
  await assertThrowsAsync(async () => {
    await Deno.readTextFile("cli/tests/fixture.json");
  }, Deno.errors.PermissionDenied);
});

unitTest({ perms: { read: true } }, function readTextFileSyncLoop(): void {
  for (let i = 0; i < 256; i++) {
    Deno.readTextFileSync("cli/tests/fixture.json");
  }
});