fix: reduce logging for deprecations

.changeset/cuddly-bars-clap.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/vite-plugin-svelte': patch
+---
+
+reduce deprecation logging to info and allow disabling it with a flag

packages/vite-plugin-svelte/src/public.d.ts

@@ -173,6 +173,13 @@ interface ExperimentalOptions {
 	 */
 	disableSvelteResolveWarnings?: boolean;
 
+	/**
+	 * disable api.sveltePreprocess deprecation warnings
+	 *
+	 * @default false
+	 */
+	disableApiSveltePreprocessWarnings?: boolean;
+
 	compileModule?: CompileModuleOptions;
 }
 

packages/vite-plugin-svelte/src/utils/constants.js

@@ -26,6 +26,9 @@ export const SVELTE_EXPORT_CONDITIONS = ['svelte'];
 export const FAQ_LINK_MISSING_EXPORTS_CONDITION =
 	'https://github.com/sveltejs/vite-plugin-svelte/blob/main/docs/faq.md#missing-exports-condition';
 
+export const LINK_TRANSFORM_WITH_PLUGIN =
+	'https://github.com/sveltejs/vite-plugin-svelte/blob/main/docs/advanced-usage.md#transform-svelte-files-with-vite-plugins';
+
 export const DEFAULT_SVELTE_EXT = ['.svelte'];
 export const DEFAULT_SVELTE_MODULE_INFIX = ['.svelte.'];
 export const DEFAULT_SVELTE_MODULE_EXT = ['.js', '.ts'];

packages/vite-plugin-svelte/src/utils/options.js

@@ -461,11 +461,12 @@ async function buildExtraConfigForDependencies(options, config) {
 		}
 	});
 	if (
+		!options.isBuild &&
 		!options.experimental?.disableSvelteResolveWarnings &&
 		packagesWithoutSvelteExportsCondition?.size > 0
 	) {
-		log.warn(
-			`WARNING: The following packages have a svelte field in their package.json but no exports condition for svelte.\n\n${[
+		log.info.once(
+			`The following packages have a svelte field in their package.json but no exports condition for svelte.\n\n${[
 				...packagesWithoutSvelteExportsCondition
 			].join('\n')}\n\nPlease see ${FAQ_LINK_MISSING_EXPORTS_CONDITION} for details.`
 		);

packages/vite-plugin-svelte/src/utils/preprocess.js

@@ -1,4 +1,5 @@
 import { log } from './log.js';
+import { LINK_TRANSFORM_WITH_PLUGIN } from './constants.js';
 
 /**
  * @param {import('../types/options.d.ts').ResolvedOptions} options
@@ -14,17 +15,24 @@ function buildExtraPreprocessors(options, config) {
 	/** @type {import('svelte/compiler').PreprocessorGroup[]} */
 	const appendPreprocessors = [];
 
-	const pluginsWithPreprocessorsDeprecated = config.plugins.filter((p) => p.api?.sveltePreprocess);
-	if (pluginsWithPreprocessorsDeprecated.length > 0) {
-		log.warn(
-			`The following plugins use the deprecated 'plugin.api.sveltePreprocess' field. Please contact their maintainers and ask them to use a vite plugin transform instead: ${pluginsWithPreprocessorsDeprecated
+	/** @type {import('vite').Plugin[]} */
+	const pluginsWithPreprocessors = config.plugins.filter((p) => p?.api?.sveltePreprocess);
+
+	if (
+		!options.isBuild &&
+		!options.experimental?.disableApiSveltePreprocessWarnings &&
+		pluginsWithPreprocessors.length > 0
+	) {
+		log.info.once(
+			`The following plugins use the deprecated 'plugin.api.sveltePreprocess' field: ${pluginsWithPreprocessors
 				.map((p) => p.name)
-				.join(', ')}`
+				.join(', ')}
+				Please contact their maintainers and ask them to use a vite plugin transform instead.
+				See ${LINK_TRANSFORM_WITH_PLUGIN} for more information.
+				`.replace(/\t+/g, '\t')
 		);
 	}
 	/** @type {import('vite').Plugin[]} */
-	const pluginsWithPreprocessors = config.plugins.filter((p) => p?.api?.sveltePreprocess);
-	/** @type {import('vite').Plugin[]} */
 	const ignored = [];
 	/** @type {import('vite').Plugin[]} */
 	const included = [];

packages/vite-plugin-svelte/types/index.d.ts

@@ -173,6 +173,13 @@ declare module '@sveltejs/vite-plugin-svelte' {
 		 */
 		disableSvelteResolveWarnings?: boolean;
 
+		/**
+		 * disable api.sveltePreprocess deprecation warnings
+		 *
+		 * @default false
+		 */
+		disableApiSveltePreprocessWarnings?: boolean;
+
 		compileModule?: CompileModuleOptions;
 	}
 

packages/vite-plugin-svelte/types/index.d.ts.map

@@ -26,6 +26,6 @@
 		null,
 		null
 	],
-	"mappings": ";;;;aAIYA,OAAOA;;WAETC,mBAAmBA;;;;;;;;;;;kBAWZC,aAAaA;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;kBAgGbC,YAAYA;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;WAiDnBC,mBAAmBA;;;;;;;;;;;;;;;;WAgBnBC,oBAAoBA;;;;;;;;;;;;;;;MAezBC,SAASA;;kBAEGC,qBAAqBA;;;;;;;;;;;;;;;;;;iBChLtBC,MAAMA;iBCMNC,cAAcA;iBCFRC,gBAAgBA",
+	"mappings": ";;;;aAIYA,OAAOA;;WAETC,mBAAmBA;;;;;;;;;;;kBAWZC,aAAaA;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;kBAgGbC,YAAYA;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;WAiDnBC,mBAAmBA;;;;;;;;;;;;;;;;;;;;;;;WAuBnBC,oBAAoBA;;;;;;;;;;;;;;;MAezBC,SAASA;;kBAEGC,qBAAqBA;;;;;;;;;;;;;;;;;;iBCvLtBC,MAAMA;iBCMNC,cAAcA;iBCFRC,gBAAgBA",
 	"ignoreList": []
 }