Function expectDiff

core/diff/streamDiff.vitest.ts:58–82

(file: string)

}

async function expectDiff(file: string) {
  const testFilePath = path.join(__dirname, "test-examples", file + ".diff");
  const testFileContents = fs.readFileSync(testFilePath, "utf-8");
  const [oldText, newText, expectedDiff] = testFileContents
    .split("\n---\n")
    .map((s) => s.replace(/^\n+/, "").trimEnd());
  const oldLines = oldText.split("\n");
  const newLines = newText.split("\n");
  const { streamDiffs, myersDiffs } = await collectDiffs(oldLines, newLines);
  const displayedDiff = displayDiff(streamDiffs);

  if (!expectedDiff || expectedDiff.trim() === "") {
    console.log(
      "Expected diff was empty. Writing computed diff to the test file",
    );
    fs.writeFileSync(
      testFilePath,
      `${oldText}\n\n---\n\n${newText}\n\n---\n\n${displayedDiff}`,
    );

    throw new Error("Expected diff is empty");
  }

  expect(displayedDiff).toEqual(expectedDiff);
}

// We use a longer `)` string here to not get
// caught by the fuzzy matcher