Studio CLI: Import each date-fns function from its own path

apps/cli/commands/preview/list.ts

@@ -3,7 +3,7 @@ import { PreviewCommandLoggerAction as LoggerAction } from '@studio/common/logge
 import { Snapshot } from '@studio/common/types/snapshot';
 import { __, _n, sprintf } from '@wordpress/i18n';
 import CliTable3 from 'cli-table3';
-import { format } from 'date-fns';
+import { format } from 'date-fns/format';
 import { readCliConfig } from 'cli/lib/cli-config/core';
 import { getSiteByFolder } from 'cli/lib/cli-config/sites';
 import {

apps/cli/commands/preview/update.ts

@@ -7,7 +7,7 @@ import { readAuthToken } from '@studio/common/lib/shared-config';
 import { PreviewCommandLoggerAction as LoggerAction } from '@studio/common/logger-actions';
 import { Snapshot } from '@studio/common/types/snapshot';
 import { __, _n, sprintf } from '@wordpress/i18n';
-import { addDays } from 'date-fns';
+import { addDays } from 'date-fns/addDays';
 import { uploadArchive, waitForSiteReady } from 'cli/lib/api';
 import { cleanup, archiveSiteContent } from 'cli/lib/archive';
 import { getSiteByFolder } from 'cli/lib/cli-config/sites';

apps/cli/lib/site-runtime-stats.ts

@@ -3,7 +3,7 @@ import {
 	SITE_FILE_ACCESS_ALL_FILES,
 	type SiteFileAccess,
 } from '@studio/common/lib/site-file-access';
-import { isSameDay } from 'date-fns';
+import { isSameDay } from 'date-fns/isSameDay';
 import { bumpStat } from 'cli/lib/bump-stat';
 import {
 	lockCliConfig,

apps/cli/lib/snapshots.ts

@@ -1,6 +1,10 @@
 import { HOUR_MS, DAY_MS, DEMO_SITE_EXPIRATION_DAYS } from '@studio/common/constants';
 import { __ } from '@wordpress/i18n';
-import { addDays, addHours, DurationUnit, formatDuration, intervalToDuration } from 'date-fns';
+import { addDays } from 'date-fns/addDays';
+import { addHours } from 'date-fns/addHours';
+import { formatDuration } from 'date-fns/formatDuration';
+import { intervalToDuration } from 'date-fns/intervalToDuration';
+import type { DurationUnit } from 'date-fns';
 
 export {
 	getSnapshotsFromConfig,

apps/cli/tests/startup-imports.test.ts

@@ -3,16 +3,24 @@ import path from 'path';
 import { describe, expect, it, vi } from 'vitest';
 
 const agentRuntimeLoaded = vi.hoisted( () => ( { value: false } ) );
+const dateFnsRootLoaded = vi.hoisted( () => ( { value: false } ) );
 
 vi.mock( '@earendil-works/pi-coding-agent', () => {
 	agentRuntimeLoaded.value = true;
 	return {};
 } );
 
+// The `date-fns` root loads every one of its functions, about 300 modules, which took
+// about 0.9 s in the packaged app. Each function has its own path, e.g. `date-fns/format`.
+vi.mock( 'date-fns', () => {
+	dateFnsRootLoaded.value = true;
+	return {};
+} );
+
 // Every `studio` command loads what the CLI entry imports statically before it
 // runs. The agent runtime is large, so only the commands that use it load it.
 describe( 'CLI startup', () => {
-	it( 'loads no agent runtime before a command runs', async () => {
+	it( 'loads no agent runtime or date-fns root before a command runs', async () => {
 		const entry = readFileSync( path.join( import.meta.dirname, '..', 'index.ts' ), 'utf8' );
 		const staticImports = [ ...entry.matchAll( /^import [^;]*? from '(cli\/[^']+)';$/gm ) ].map(
 			( [ , specifier ] ) => specifier
@@ -24,5 +32,6 @@ describe( 'CLI startup', () => {
 		}
 
 		expect( agentRuntimeLoaded.value ).toBe( false );
+		expect( dateFnsRootLoaded.value ).toBe( false );
 	} );
 } );

packages/common/lib/bump-stat.ts

@@ -1,4 +1,6 @@
-import { isSameDay, isSameMonth, isSameWeek } from 'date-fns';
+import { isSameDay } from 'date-fns/isSameDay';
+import { isSameMonth } from 'date-fns/isSameMonth';
+import { isSameWeek } from 'date-fns/isSameWeek';
 
 // Database columns are varchar(32). Group limit is 27 to account for the '-a11n' suffix
 // added by the backend for Automattic requests (27 + 5 = 32).

packages/common/lib/generate-backup-filename.ts

@@ -1,4 +1,4 @@
-import { format } from 'date-fns';
+import { format } from 'date-fns/format';
 import { sanitizeFolderName } from '@studio/common/lib/sanitize-folder-name';
 
 export function generateBackupFilename( name: string ) {