Function planMigrationFiles

packages/migrate/src/node.ts:59–123

(options: MigrateFilesOptions)

 * mutating the destination tree.
 */
export async function planMigrationFiles(options: MigrateFilesOptions): Promise<MigrationFilePlan> {
  const sourceRoot = resolve(options.sourceRoot);
  const outputRoot = resolve(options.outputRoot ?? sourceRoot);
  const canonicalSourceRoot = await canonicalDirectory(sourceRoot, 'sourceRoot');
  const canonicalOutputRoot = await canonicalFutureDirectory(outputRoot, 'outputRoot');
  const outputName = options.outputName ?? localSpecOutputName;
  const outputMode = options.mode ?? 'unselected';
  const sources: PlannedSource[] = [];
  const canonicalSources = new Set<string>();

  for (const input of options.files) {
    const sourcePath = resolve(sourceRoot, input);
    assertContained(sourceRoot, sourcePath, `Source path is outside sourceRoot: ${input}`);

    const canonicalSourcePath = await realpath(sourcePath);
    assertContained(canonicalSourceRoot, canonicalSourcePath, `Source path resolves outside sourceRoot: ${input}`);
    if (canonicalSources.has(canonicalSourcePath)) {
      throw new Error(`Duplicate source path: ${input}`);
    }
    canonicalSources.add(canonicalSourcePath);

    const sourceStats = await stat(canonicalSourcePath);
    if (!sourceStats.isFile()) throw new Error(`Source path is not a regular file: ${input}`);

    const localSourcePath = relative(sourceRoot, sourcePath).replaceAll('\\', '/');
    sources.push({
      sourcePath,
      canonicalSourcePath,
      localSourcePath,
      source: await readFile(canonicalSourcePath, 'utf8'),
    });
  }

  const files: MigratedFile[] = [];
  const canonicalOutputs = new Set<string>();
  for (const plannedSource of sources) {
    const outputLocalName = outputName({ sourcePath: plannedSource.sourcePath, sourceRoot, mode: outputMode });
    const outputPath = safeOutputPath(outputRoot, outputLocalName);
    const canonicalOutputPath = await canonicalFuturePath(outputPath);
    assertContained(canonicalOutputRoot, canonicalOutputPath, `Output path resolves outside outputRoot: ${outputLocalName}`);

    if (canonicalSources.has(canonicalOutputPath)) {
      throw new Error(`Output path aliases a source file: ${outputLocalName}`);
    }
    if (canonicalOutputs.has(canonicalOutputPath)) {
      throw new Error(`Duplicate output path: ${outputLocalName}`);
    }
    canonicalOutputs.add(canonicalOutputPath);

    const provenance: SourceProvenance = {
      repository: options.sourceRepository,
      sha: options.sourceSha,
      path: plannedSource.localSourcePath,
    };
    const result = migrateTestSource(plannedSource.source, {
      ...options,
      mode: options.mode,
      provenance,