Function estimate

packages/cli/src/cli/cmd/run/estimate.ts:33–125

(
  input: CmdRunContext,
)

 * written, or billed; lockfile and target files stay untouched.
 */
export default async function estimate(
  input: CmdRunContext,
): Promise<CmdRunContext> {
  console.log(chalk.hex(colors.orange)("[Estimate]"));

  if (!input.localizer?.estimate) {
    throw new Error(
      `Cost estimate is not available for the "${input.localizer?.id}" provider. ` +
        `Estimates use Lingo.dev server-side pricing — remove --estimate or switch to the Lingo.dev provider.`,
    );
  }

  const charsByLocale = new Map<string, number>();

  return new Listr<CmdRunContext>(
    [
      {
        title: "Computing translation delta",
        task: async (ctx, task) => {
          if (!ctx.tasks.length) {
            task.title = "Nothing to estimate — everything is up to date.";
            return;
          }

          for (const runTask of ctx.tasks) {
            const bucketLoader = createLoaderForTask(runTask);
            const deltaProcessor = createDeltaProcessor(
              runTask.bucketPathPattern,
            );
            const checksums = await deltaProcessor.loadChecksums();
            const sourceData = await bucketLoader.pull(runTask.sourceLocale);
            const targetData = await bucketLoader.pull(runTask.targetLocale);
            const delta = await deltaProcessor.calculateDelta({
              sourceData,
              targetData,
              checksums,
            });
            const processableData = computeProcessableData(
              sourceData,
              delta,
              ctx.flags.force,
              runTask.onlyKeys,
            );

            const chars = countTranslatableChars(processableData);
            charsByLocale.set(
              runTask.targetLocale,
              (charsByLocale.get(runTask.targetLocale) ?? 0) + chars,
            );
          }

          task.title = `Delta computed for ${chalk.hex(colors.yellow)(
            ctx.tasks.length.toString(),
          )} task(s)`;
        },
      },
      {
        title: "Fetching cost estimate",