fix: type SvelteKit hooks and params files at their configured locations

.changeset/kit-files-config.md

@@ -0,0 +1,7 @@
+---
+'svelte2tsx': patch
+'svelte-language-server': patch
+'svelte-check': patch
+---
+
+fix: type SvelteKit hooks and params files at the locations set in the Svelte config's `files` option

packages/language-server/src/index.ts

@@ -1,6 +1,7 @@
 export * from './server';
 export { offsetAt, positionAt, getLineOffsets } from './lib/documents';
 export { normalizePath } from './utils';
+export { defaultKitFilesSettings, resolveKitFilesSettings } from './lib/documents/configLoader';
 export {
     mapSvelteCheckDiagnostics,
     SvelteCheck,

packages/language-server/src/lib/documents/configLoader.ts

@@ -12,6 +12,7 @@ import _fs from 'fs';
 import { URL } from 'url';
 import { FileMap } from './fileCollection';
 import ts from 'typescript';
+import { InternalHelpers } from 'svelte2tsx';
 
 export type InternalPreprocessorGroup = PreprocessorGroup & {
     /**
@@ -41,6 +42,13 @@ export interface ExplicitConfigScope {
 
 type LoadConfigFromDirectoryFn = typeof loadConfigFromDirectory;
 
+export const defaultKitFilesSettings: InternalHelpers.KitFilesSettings = {
+    paramsPath: 'src/params',
+    serverHooksPath: 'src/hooks.server',
+    clientHooksPath: 'src/hooks.client',
+    universalHooksPath: 'src/hooks'
+};
+
 const DEFAULT_OPTIONS: CompileOptions = {
     dev: true
 };
@@ -357,6 +365,17 @@ export class ConfigLoader {
         }
     }
 
+    /**
+     * Where the SvelteKit hooks and params files are for the file, from its config's `files` option
+     */
+    getKitFilesSettings(file: string): InternalHelpers.KitFilesSettings {
+        const files = this.getConfig(file)?.files;
+        const configPath = this.filePathToConfigPath.get(file);
+        return files && configPath
+            ? resolveKitFilesSettings(files, this.path.dirname(configPath))
+            : defaultKitFilesSettings;
+    }
+
     /**
      * Like `getConfig`, but will search for a config above if no config found.
      */
@@ -452,6 +471,38 @@ export class ConfigLoader {
     }
 }
 
+/**
+ * Where SvelteKit's hooks and params files are, from a config's `files` option. Like SvelteKit, a
+ * location the config sets, directly or through `files.src`, is resolved in the config's directory.
+ * The option comes from user code, so anything that isn't a string is ignored.
+ */
+export function resolveKitFilesSettings(
+    files: unknown,
+    configDirectory: string
+): InternalHelpers.KitFilesSettings {
+    const { src, params, hooks }: Record<string, unknown> = isRecord(files) ? files : {};
+    const { server, client, universal }: Record<string, unknown> = isRecord(hooks) ? hooks : {};
+    const locate = (location: unknown, name: string) => {
+        if (typeof location === 'string') {
+            return _path.resolve(configDirectory, location);
+        }
+        if (typeof src === 'string') {
+            return _path.resolve(configDirectory, src, name);
+        }
+        return `src/${name}`;
+    };
+    return {
+        paramsPath: locate(params, 'params'),
+        serverHooksPath: locate(server, 'hooks.server'),
+        clientHooksPath: locate(client, 'hooks.client'),
+        universalHooksPath: locate(universal, 'hooks')
+    };
+}
+
+function isRecord(value: unknown): value is Record<string, unknown> {
+    return typeof value === 'object' && value !== null;
+}
+
 function getSvelteConfigExtensions(loadSvelteConfigTs: boolean) {
     return loadSvelteConfigTs
         ? [...SVELTE_CONFIG_EXTENSIONS, ...SVELTE_CONFIG_TS_EXTENSIONS]

packages/language-server/src/plugins/typescript-go/features/DiagnosticsProvider.ts

@@ -36,6 +36,7 @@ import {
 import { DiagnosticsProvider } from '../../interfaces';
 import {
     DocumentSnapshot,
+    getKitFilesSettings,
     JSOrTSDocumentSnapshot,
     SvelteDocumentSnapshot,
     SvelteSnapshotOptions
@@ -338,12 +339,6 @@ export class SvelteCheckTSGoDiagnosticsProvider implements DiagnosticsProvider {
         Pick<FileSystem, 'readFile' | 'fileExists' | 'getAccessibleEntries'>
     > {
         const service = this;
-        const kitFiles: Parameters<typeof internalHelpers.isKitFile>[1] = {
-            serverHooksPath: 'src/hooks.client',
-            clientHooksPath: 'src/hooks.client',
-            universalHooksPath: 'src/hooks',
-            paramsPath: 'src/params'
-        };
 
         return {
             getAccessibleEntries(directory: string) {
@@ -392,7 +387,7 @@ export class SvelteCheckTSGoDiagnosticsProvider implements DiagnosticsProvider {
 
                 if (
                     normalizedPath.endsWith('node_modules/svelte/types/index.d.ts') ||
-                    internalHelpers.isKitFile(normalizedPath, kitFiles)
+                    internalHelpers.isKitFile(normalizedPath, getKitFilesSettings(normalizedPath))
                 ) {
                     const snapshot = DocumentSnapshot.fromFilePath(
                         normalizedPath,

packages/language-server/src/plugins/typescript/DocumentSnapshot.ts

@@ -1,7 +1,7 @@
 import { EncodedSourceMap, TraceMap, originalPositionFor } from '@jridgewell/trace-mapping';
 // @ts-ignore
 import { TemplateNode } from 'svelte/types/compiler/interfaces';
-import { svelte2tsx, IExportedNames, internalHelpers } from 'svelte2tsx';
+import { svelte2tsx, IExportedNames, internalHelpers, InternalHelpers } from 'svelte2tsx';
 import ts from 'typescript';
 import { Position, Range, TextDocumentContentChangeEvent } from 'vscode-languageserver';
 import {
@@ -29,7 +29,7 @@ import { Logger } from '../../logger';
 import { dirname, resolve } from 'path';
 import { URI } from 'vscode-uri';
 import { surroundWithIgnoreComments } from './features/utils';
-import { configLoader } from '../../lib/documents/configLoader';
+import { configLoader, defaultKitFilesSettings } from '../../lib/documents/configLoader';
 
 /**
  * Computes the change range between two snapshots by scanning for the first and last
@@ -477,6 +477,13 @@ export class SvelteDocumentSnapshot implements DocumentSnapshot {
     }
 }
 
+export function getKitFilesSettings(filePath: string): InternalHelpers.KitFilesSettings {
+    // Declaration files aren't hooks or params files, and there are many in node_modules
+    return filePath.endsWith('.d.ts')
+        ? defaultKitFilesSettings
+        : configLoader.getKitFilesSettings(filePath);
+}
+
 /**
  * A js/ts document snapshot suitable for the ts language service and the plugin.
  * Since no mapping has to be done here, it also implements the mapper interface.
@@ -496,10 +503,6 @@ export class JSOrTSDocumentSnapshot extends IdentityMapper implements DocumentSn
         inserted: string;
         total: number;
     }> = [];
-    private paramsPath = 'src/params';
-    private serverHooksPath = 'src/hooks.server';
-    private clientHooksPath = 'src/hooks.client';
-    private universalHooksPath = 'src/hooks';
 
     isOpenedInClient(): boolean {
         return this.openedByClient;
@@ -633,12 +636,7 @@ export class JSOrTSDocumentSnapshot extends IdentityMapper implements DocumentSn
         const result = internalHelpers.upsertKitFile(
             ts,
             this.filePath,
-            {
-                clientHooksPath: this.clientHooksPath,
-                paramsPath: this.paramsPath,
-                serverHooksPath: this.serverHooksPath,
-                universalHooksPath: this.universalHooksPath
-            },
+            getKitFilesSettings(this.filePath),
             () => this.createSource(),
             surroundWithIgnoreComments
         );
@@ -649,16 +647,6 @@ export class JSOrTSDocumentSnapshot extends IdentityMapper implements DocumentSn
             return;
         }
 
-        if (!this.kitFile) {
-            const files = configLoader.getConfig(this.filePath)?.files;
-            if (files) {
-                this.paramsPath ||= files.params;
-                this.serverHooksPath ||= files.hooks?.server;
-                this.clientHooksPath ||= files.hooks?.client;
-                this.universalHooksPath ||= files.hooks?.universal;
-            }
-        }
-
         const { text, addedCode } = result;
 
         this.kitFile = true;

packages/language-server/test/plugins/typescript/DocumentSnapshot.test.ts

@@ -1,11 +1,13 @@
 import * as assert from 'assert';
+import * as path from 'path';
 import ts from 'typescript';
 import {
     computeChangeRange,
     JSOrTSDocumentSnapshot,
     SvelteDocumentSnapshot
 } from '../../../src/plugins/typescript/DocumentSnapshot';
 import { Document } from '../../../src/lib/documents';
+import { configLoader } from '../../../src/lib/documents/configLoader';
 import { pathToUrl } from '../../../src/utils';
 
 /**
@@ -188,3 +190,29 @@ describe('SvelteDocumentSnapshot.getChangeRange', () => {
         assert.strictEqual(range, undefined);
     });
 });
+
+describe('JSOrTSDocumentSnapshot SvelteKit files', () => {
+    it('types hooks and params at the locations set in the Svelte config', async () => {
+        const project = path.join(__dirname, 'testfiles', 'kit-files');
+        await configLoader.loadConfigs(project);
+        const handle = 'export const handle = ({ event, resolve }) => resolve(event);';
+        const hooks = new JSOrTSDocumentSnapshot(
+            0,
+            path.join(project, 'app/server/hooks.ts'),
+            handle
+        );
+        assert.ok(hooks.getFullText().includes(').Handle'), 'configured server hook must be typed');
+        const params = new JSOrTSDocumentSnapshot(
+            0,
+            path.join(project, 'app/params/id.ts'),
+            'export const match = (param) => true;'
+        );
+        assert.ok(params.getFullText().includes(': string'));
+        const elsewhere = new JSOrTSDocumentSnapshot(
+            0,
+            path.join(project, 'vendor/app/server/hooks.ts'),
+            handle
+        );
+        assert.ok(!elsewhere.kitFile);
+    });
+});

packages/language-server/test/plugins/typescript/testfiles/kit-files/svelte.config.js

@@ -0,0 +1,5 @@
+module.exports = {
+    kit: {
+        files: { src: './app', hooks: { server: 'app/server/hooks' } }
+    }
+};

packages/svelte-check/src/incremental.ts

@@ -9,7 +9,9 @@ import {
     mapSvelteCheckDiagnostics,
     offsetAt,
     positionAt,
-    getLineOffsets
+    getLineOffsets,
+    defaultKitFilesSettings,
+    resolveKitFilesSettings
 } from 'svelte-language-server';
 import { loadConfig } from '@sveltejs/load-config';
 import { findFiles } from './utils';
@@ -94,28 +96,12 @@ function toRelativePosix(baseDir: string, targetPath: string) {
     return toPosixPath(relative || '.');
 }
 
-/**
- * Default SvelteKit file paths used when svelte.config.js doesn't specify custom paths.
- */
-const defaultKitFilesSettings: InternalHelpers.KitFilesSettings = {
-    paramsPath: 'src/params',
-    serverHooksPath: 'src/hooks.server',
-    clientHooksPath: 'src/hooks.client',
-    universalHooksPath: 'src/hooks'
-};
-
-function kitFilesSettingsFromConfig(config: any): InternalHelpers.KitFilesSettings {
-    if (!config?.files) {
-        return defaultKitFilesSettings;
-    }
-
-    const files = config.files;
-    return {
-        paramsPath: files.params ?? defaultKitFilesSettings.paramsPath,
-        serverHooksPath: files.hooks?.server ?? defaultKitFilesSettings.serverHooksPath,
-        clientHooksPath: files.hooks?.client ?? defaultKitFilesSettings.clientHooksPath,
-        universalHooksPath: files.hooks?.universal ?? defaultKitFilesSettings.universalHooksPath
-    };
+// SvelteKit 3 puts its options at the top level, SvelteKit 2 under `kit`
+function getKitFilesOption(config: Record<string, unknown>): unknown {
+    const kitOptions = 'files' in config ? config : config.kit;
+    return typeof kitOptions === 'object' && kitOptions !== null && 'files' in kitOptions
+        ? kitOptions.files
+        : undefined;
 }
 
 /**
@@ -134,9 +120,9 @@ async function loadKitFilesSettings(
         return defaultKitFilesSettings;
     }
 
-    return kitFilesSettingsFromConfig(
-        // SvelteKit 3 puts its options at the top level
-        'files' in result.config ? result.config : result.config.kit
+    return resolveKitFilesSettings(
+        getKitFilesOption(result.config),
+        path.dirname(result.configFilePath)
     );
 }
 

packages/svelte2tsx/index.d.ts

@@ -209,6 +209,10 @@ export namespace InternalHelpers {
         inserted: string;
     }
 
+    /**
+     * Where the hooks and params files are, without extension. An absolute path names that one
+     * location; a relative one, like the defaults, matches in any folder.
+     */
     export interface KitFilesSettings {
         serverHooksPath: string;
         clientHooksPath: string;

packages/svelte2tsx/src/helpers/sveltekit.ts

@@ -16,6 +16,10 @@ export interface AddedCode {
     inserted: string;
 }
 
+/**
+ * Where the hooks and params files are, without extension. An absolute path names that one
+ * location; a relative one, like the defaults, matches in any folder.
+ */
 export interface KitFilesSettings {
     serverHooksPath: string;
     clientHooksPath: string;
@@ -67,8 +71,8 @@ export function isKitErrorFile(basename: string): boolean {
 export function isHooksFile(fileName: string, basename: string, hooksPath: string): boolean {
     return (
         ((basename === 'index.ts' || basename === 'index.js') &&
-            fileName.slice(0, -basename.length - 1).endsWith(hooksPath)) ||
-        fileName.slice(0, -path.extname(basename).length).endsWith(hooksPath)
+            isAtLocation(path.dirname(fileName), hooksPath)) ||
+        isAtLocation(fileName.slice(0, -path.extname(basename).length), hooksPath)
     );
 }
 
@@ -77,12 +81,19 @@ export function isHooksFile(fileName: string, basename: string, hooksPath: strin
  */
 export function isParamsFile(fileName: string, basename: string, paramsPath: string): boolean {
     return (
-        fileName.slice(0, -basename.length - 1).endsWith(paramsPath) &&
+        isAtLocation(path.dirname(fileName), paramsPath) &&
         !basename.includes('.test') &&
         !basename.includes('.spec')
     );
 }
 
+// Absolute locations are compared as paths, so separators and the drive letter's case don't matter
+function isAtLocation(filePath: string, location: string): boolean {
+    return path.isAbsolute(location)
+        ? path.relative(location, filePath) === ''
+        : filePath.endsWith(location);
+}
+
 export function upsertKitFile(
     ts: _ts,
     fileName: string,