testSuitesRunAgainOnlyWhenCodeTheyRanChanged

tcmts.cli.test.e2e.suites.testSuitesRunAgainOnlyWhenCodeTheyRanChanged · #c63x4ona · term

A package's suites run its command, and run again only when code they ran changed; a result holds again when that code is back as it was.

import { okIn, tcmIn, tempDir } from "#codebase/tcmts/cli/test/e2e/harness";
import assert from "node:assert/strict";
import fs from "node:fs";
import path from "node:path";

export const testSuitesRunAgainOnlyWhenCodeTheyRanChanged = () => {
  const dir = tempDir("suites");
  const ok = (...args: string[]) => okIn(dir, ...args);
  const scratch = (ns: string, text: string) =>
    fs.writeFileSync(path.join(dir, "scratch.ts"), `// tcm: namespace ${ns}\n${text}`);
  ok("init");
  scratch(
    "greeter",
    `export const greet = (name: string) => \`hello, \${name}\`;
export const shout = (s: string) => s.toUpperCase();
export const main = (...args: string[]) => console.log(greet(args[0] ?? "world"));
export const manifest = { name: "greeter", bin: { greet: "main" }, suites: { greet: ["e2e"] } };
`,
  );
  ok("add");
  // the test finds the command in GREET_BIN
  scratch(
    "greeter.e2e",
    `import assert from "node:assert/strict";
import { spawnSync } from "node:child_process";
export const testGreets = () => {
  const r = spawnSync(process.execPath, [process.env.GREET_BIN!, "tcm"], { encoding: "utf8" });
  assert.equal(r.stdout, "hello, tcm\\n");
};
`,
  );
  ok("add");

  assert.match(
    ok("test"),
    /suites \(running greet\)\n {2}✓ greeter\.e2e\.testGreets[\s\S]*suites: 1 passed, 0 failed\n/,
  );
  assert.match(ok("test"), /suites: 1 passed, 0 failed \(1 cached\)/);
  // (it's run as a program, not with the test definitions)
  assert.match(ok("test", "--definitions"), /no tests/);

  // shout isn't run by the test: changing it keeps the result
  scratch("greeter", `export const shout = (s: string) => s.toUpperCase() + "!";\n`);
  ok("update");
  assert.match(ok("test"), /\(1 cached\)/);

  // greet is, so changing it runs the test again
  scratch("greeter", `export const greet = (name: string) => \`hi, \${name}\`;\n`);
  ok("update");
  const failed = tcmIn(dir, "test");
  assert.equal(failed.status, 1);
  assert.match(
    failed.out,
    /✗ greeter\.e2e\.testGreets[\s\S]*AssertionError[\s\S]*suites: 0 passed, 1 failed\n/,
  );
  // a failure isn't kept: with nothing changed it runs again (it may have failed for what's around it)
  const again = tcmIn(dir, "test");
  assert.match(again.out, /suites: 0 passed, 1 failed\n/);
  assert.doesNotMatch(again.out, /cached/);

  // changed back, the result from when it was this way holds again (as when branches are tested by turns)
  scratch("greeter", `export const greet = (name: string) => \`hello, \${name}\`;\n`);
  ok("update");
  assert.match(ok("test"), /suites: 1 passed, 0 failed \(1 cached\)/);
}

testSuitesRunAgainOnlyWhenCodeTheyRanChanged

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