Deno content server - medium course - section 3 getContent UT

fileService_test.ts

import { getContent } from "../../fileService.ts";
import {
  assert,
  assertExists,
  assertThrowsAsync,
} from "https://deno.land/std/testing/asserts.ts";

async function readStream(r: ReadableStream) {
  const rd = r.getReader();
  assertExists(rd);
  let bytesRead = 0;
  while (1) {
    const d = await rd.read();
    if (d.done) {
      break;
    }
    assertExists(d);
    assertExists(d.value);
    bytesRead += d.value.length;
  }
  return bytesRead;
}

Deno.test("Inexistent file", async () => {
  assertThrowsAsync(async () => {
    await getContent("someRandomFile.abc");
  }, Deno.errors.NotFound);
});

Deno.test("Directory", async () => {
  assertThrowsAsync(async () => {
    await getContent("data");
  }, Deno.errors.BadResource);
});

Deno.test("Text file textFile.txt", async () => {
  const ret = await getContent("data/textFile.txt");
  assertExists(ret);
  assertExists(ret.len);
  assertExists(ret.content);
  assert(ret.len === 22);
  assert(await readStream(ret.content) === 22);
});

Deno.test("PDF file pdfFile.txt", async () => {
  const ret = await getContent("data/pdfFile.pdf");
  assertExists(ret);
  assertExists(ret.len);
  assertExists(ret.content);
  assert(ret.len === 69273);
  assert(await readStream(ret.content) === 69273);
});