Function readWorkspace

packages/angular_devkit/core/src/workspace/core.ts:60–112

(
  path: string,
  host: WorkspaceHost,
  format?: WorkspaceFormat,
  // return type will eventually have a `diagnostics` property as well
)

 * the `workspace` property.
 */
export async function readWorkspace(
  path: string,
  host: WorkspaceHost,
  format?: WorkspaceFormat,
  // return type will eventually have a `diagnostics` property as well
): Promise<{ workspace: WorkspaceDefinition }> {
  if (await host.isDirectory(path)) {
    // TODO: Warn if multiple found (requires diagnostics support)
    const directory = normalize(path);
    let found = false;
    for (const [name, nameFormat] of Object.entries(workspaceFiles)) {
      if (format !== undefined && format !== nameFormat) {
        continue;
      }

      const potential = getSystemPath(join(directory, name));
      if (await host.isFile(potential)) {
        path = potential;
        format = nameFormat;
        found = true;
        break;
      }
    }
    if (!found) {
      throw new Error(
        'Unable to locate a workspace file for workspace path. Are you missing an `angular.json`' +
          ' or `.angular.json` file?',
      );
    }
  } else if (format === undefined) {
    const filename = basename(normalize(path));
    if (filename in workspaceFiles) {
      format = workspaceFiles[filename];
    }
  }

  if (format === undefined) {
    throw new Error('Unable to determine format for workspace path.');
  }

  let workspace;
  switch (format) {
    case WorkspaceFormat.JSON:
      workspace = await readJsonWorkspace(path, host);
      break;
    default:
      throw new Error('Unsupported workspace format.');
  }

  formatLookup.set(workspace, WorkspaceFormat.JSON);

  return { workspace };
}

/**
 * Writes a `WorkspaceDefinition` to the underlying storage via the provided `WorkspaceHost`.