feat: add rootDir option and set __svelte_meta.file like in svelte4

.changeset/khaki-mails-scream.md

@@ -0,0 +1,5 @@
+---
+"svelte": patch
+---
+
+feat: introduce rootDir option and strip rootDir from filename in dev

.changeset/kind-doors-grin.md

@@ -0,0 +1,5 @@
+---
+"svelte": patch
+---
+
+fix: rename **svelte_meta.filename to **svelte_meta.file to align with svelte4

packages/svelte/src/compiler/phases/3-transform/client/transform-client.js

@@ -473,10 +473,12 @@ export function client_component(source, analysis, options) {
 	if (options.dev) {
 		if (options.filename) {
 			let filename = options.filename;
-			if (/(\/|\w:)/.test(options.filename)) {
-				// filename is absolute — truncate it
-				const parts = filename.split(/[/\\]/);
-				filename = parts.length > 3 ? ['...', ...parts.slice(-3)].join('/') : filename;
+			if(options.rootDir && filename.startsWith(options.rootDir)) {
+				filename = filename.replace(options.rootDir,'');
+				if(filename !== options.filename) {
+					// if after remove of rootDir first char is a path separator, remove that too
+					filename = filename.replace(/^[/\\]/,'')
+				}
 			}
 
 			// add `App.filename = 'App.svelte'` so that we can print useful messages later

packages/svelte/src/compiler/types/index.d.ts

@@ -216,12 +216,19 @@ export interface ModuleCompileOptions {
 	 * Used for debugging hints and sourcemaps. Your bundler plugin will set it automatically.
 	 */
 	filename?: string;
+
+	/**
+	 * Used for ensuring filenames don't leak filesystem information. Your bundler plugin will set it automatically.
+	 * @default process.cwd() on node-like environments, undefined elsewhere
+	 */
+	rootDir?: string;
 }
 
 // The following two somewhat scary looking types ensure that certain types are required but can be undefined still
 
-export type ValidatedModuleCompileOptions = Omit<Required<ModuleCompileOptions>, 'filename'> & {
+export type ValidatedModuleCompileOptions = Omit<Required<ModuleCompileOptions>, 'filename' | 'rootDir'> & {
 	filename: ModuleCompileOptions['filename'];
+	rootDir: ModuleCompileOptions['rootDir'];
 };
 
 export type ValidatedCompileOptions = ValidatedModuleCompileOptions &

packages/svelte/src/compiler/validate-options.js

@@ -10,6 +10,10 @@ import * as w from './warnings.js';
 const common = {
 	filename: string(undefined),
 
+	// default to process.cwd() where it exists to replicate svelte4 behavior
+	// see https://github.com/sveltejs/svelte/blob/b62fc8c8fd2640c9b99168f01b9d958cb2f7574f/packages/svelte/src/compiler/compile/Component.js#L211
+	rootDir: string(process?.cwd?.()),
+
 	dev: boolean(false),
 
 	generate: validator('client', (input, keypath) => {

packages/svelte/src/internal/client/dev/elements.js

@@ -34,7 +34,7 @@ export function add_locations(fn, filename, locations) {
 function assign_location(element, filename, location) {
 	// @ts-expect-error
 	element.__svelte_meta = {
-		loc: { filename, line: location[0], column: location[1] }
+		loc: { file: filename, line: location[0], column: location[1] }
 	};
 
 	if (location[2]) {

packages/svelte/src/internal/client/dom/blocks/svelte-element.js

@@ -116,7 +116,7 @@ export function element(anchor, get_tag, is_svg, render_fn, get_namespace, locat
 						// @ts-expect-error
 						element.__svelte_meta = {
 							loc: {
-								filename,
+								file: filename,
 								line: location[0],
 								column: location[1]
 							}

packages/svelte/tests/runtime-runes/samples/non-local-mutation-discouraged/_config.js

@@ -26,7 +26,7 @@ export default test({
 		assert.htmlEqual(target.innerHTML, `<button>clicks: 1</button>`);
 
 		assert.deepEqual(warnings, [
-			'.../samples/non-local-mutation-discouraged/Counter.svelte mutated a value owned by .../samples/non-local-mutation-discouraged/main.svelte. This is strongly discouraged. Consider passing values to child components with `bind:`, or use a callback instead'
+			'packages/svelte/tests/runtime-runes/samples/non-local-mutation-discouraged/Counter.svelte mutated a value owned by packages/svelte/tests/runtime-runes/samples/non-local-mutation-discouraged/main.svelte. This is strongly discouraged. Consider passing values to child components with `bind:`, or use a callback instead'
 		]);
 	}
 });

packages/svelte/tests/runtime-runes/samples/non-local-mutation-with-binding-2/_config.js

@@ -8,6 +8,6 @@ export default test({
 	},
 
 	warnings: [
-		'.../samples/non-local-mutation-with-binding-2/Intermediate.svelte passed a value to .../samples/non-local-mutation-with-binding-2/Counter.svelte with `bind:`, but the value is owned by .../samples/non-local-mutation-with-binding-2/main.svelte. Consider creating a binding between .../samples/non-local-mutation-with-binding-2/main.svelte and .../samples/non-local-mutation-with-binding-2/Intermediate.svelte'
+		'packages/svelte/tests/runtime-runes/samples/non-local-mutation-with-binding-2/Intermediate.svelte passed a value to packages/svelte/tests/runtime-runes/samples/non-local-mutation-with-binding-2/Counter.svelte with `bind:`, but the value is owned by packages/svelte/tests/runtime-runes/samples/non-local-mutation-with-binding-2/main.svelte. Consider creating a binding between packages/svelte/tests/runtime-runes/samples/non-local-mutation-with-binding-2/main.svelte and packages/svelte/tests/runtime-runes/samples/non-local-mutation-with-binding-2/Intermediate.svelte'
 	]
 });

packages/svelte/tests/runtime-runes/samples/non-local-mutation-with-binding-3/_config.js

@@ -33,7 +33,7 @@ export default test({
 		assert.htmlEqual(target.innerHTML, `<button>clicks: 1</button><button>clicks: 1</button>`);
 
 		assert.deepEqual(warnings, [
-			'.../samples/non-local-mutation-with-binding-3/Counter.svelte mutated a value owned by .../samples/non-local-mutation-with-binding-3/main.svelte. This is strongly discouraged. Consider passing values to child components with `bind:`, or use a callback instead'
+			'packages/svelte/tests/runtime-runes/samples/non-local-mutation-with-binding-3/Counter.svelte mutated a value owned by packages/svelte/tests/runtime-runes/samples/non-local-mutation-with-binding-3/main.svelte. This is strongly discouraged. Consider passing values to child components with `bind:`, or use a callback instead'
 		]);
 	}
 });

packages/svelte/tests/runtime-runes/samples/svelte-meta-dynamic/_config.js

@@ -14,14 +14,14 @@ export default test({
 
 		// @ts-expect-error
 		assert.deepEqual(ps[0].__svelte_meta.loc, {
-			filename: '.../samples/svelte-meta-dynamic/main.svelte',
+			file: 'packages/svelte/tests/runtime-runes/samples/svelte-meta-dynamic/main.svelte',
 			line: 7,
 			column: 0
 		});
 
 		// @ts-expect-error
 		assert.deepEqual(ps[1].__svelte_meta.loc, {
-			filename: '.../samples/svelte-meta-dynamic/main.svelte',
+			file: 'packages/svelte/tests/runtime-runes/samples/svelte-meta-dynamic/main.svelte',
 			line: 13,
 			column: 0
 		});
@@ -32,7 +32,7 @@ export default test({
 
 		// @ts-expect-error
 		assert.deepEqual(strong.__svelte_meta.loc, {
-			filename: '.../samples/svelte-meta-dynamic/main.svelte',
+			file: 'packages/svelte/tests/runtime-runes/samples/svelte-meta-dynamic/main.svelte',
 			line: 10,
 			column: 1
 		});

packages/svelte/tests/runtime-runes/samples/svelte-meta/_config.js

@@ -14,14 +14,14 @@ export default test({
 
 		// @ts-expect-error
 		assert.deepEqual(ps[0].__svelte_meta.loc, {
-			filename: '.../samples/svelte-meta/main.svelte',
+			file: 'packages/svelte/tests/runtime-runes/samples/svelte-meta/main.svelte',
 			line: 7,
 			column: 0
 		});
 
 		// @ts-expect-error
 		assert.deepEqual(ps[1].__svelte_meta.loc, {
-			filename: '.../samples/svelte-meta/main.svelte',
+			file: 'packages/svelte/tests/runtime-runes/samples/svelte-meta/main.svelte',
 			line: 13,
 			column: 0
 		});
@@ -32,7 +32,7 @@ export default test({
 
 		// @ts-expect-error
 		assert.deepEqual(strong.__svelte_meta.loc, {
-			filename: '.../samples/svelte-meta/main.svelte',
+			file: 'packages/svelte/tests/runtime-runes/samples/svelte-meta/main.svelte',
 			line: 10,
 			column: 1
 		});