import { assertStringIncludes } from "@std/assert";
import { describe, it as test } from "@std/testing/bdd";

const TEST_WORKFLOW_PATH = ".github/workflows/test.yml";

const readWorkflow = (): Promise<string> =>
  Deno.readTextFile(TEST_WORKFLOW_PATH);

/** The `on:` block, which ends at the next top-level key. */
const triggers = (workflow: string): string => {
  const start = workflow.indexOf("\non:\n");
  if (start < 0) throw new Error(`${TEST_WORKFLOW_PATH} declares no triggers`);
  const body = workflow.slice(start + 1);
  const end = body.search(/\n[a-z]/);
  return end < 0 ? body : body.slice(0, end);
};

describe("Test workflow triggers", () => {
  test("does not run the suite twice on a merge queue branch", async () => {
    // A queue branch arrives as a push, so without this the suite runs once
    // for `push` and again for `merge_group`. A stalled duplicate once timed
    // the queue out an hour after the real run had passed.
    assertStringIncludes(
      triggers(await readWorkflow()),
      'branches-ignore: [main, "gh-readonly-queue/**"]',
    );
  });

  test("still reports on a merge queue branch", async () => {
    // `checks`, `specs`, and `test` are required status checks on `main`
    // (ruleset 21611101, required as of issue #2295). Once checks are
    // required, a queue branch with no `merge_group` run reports nothing,
    // and the queue waits for a check that never arrives.
    assertStringIncludes(triggers(await readWorkflow()), "merge_group:");
  });

  test("still runs on every branch a person pushes", async () => {
    assertStringIncludes(triggers(await readWorkflow()), "push:");
  });
});