more attempt to fix memory issues in sapper workspace (#967)

* more attempt to fix memory issues in sapper workspace

* fix filename check

Author: jasonlyu123

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

@@ -122,3 +122,5 @@ export class SnapshotManager {
         }
     }
 }
+
+export const ignoredBuildDirectories = ['__sapper__', '.svelte'];

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

@@ -64,7 +64,7 @@ import { getDirectiveCommentCompletions } from './features/getDirectiveCommentCo
 import { FindReferencesProviderImpl } from './features/FindReferencesProvider';
 import { SelectionRangeProviderImpl } from './features/SelectionRangeProvider';
 import { SignatureHelpProviderImpl } from './features/SignatureHelpProvider';
-import { SnapshotManager } from './SnapshotManager';
+import { ignoredBuildDirectories, SnapshotManager } from './SnapshotManager';
 import { SemanticTokensProviderImpl } from './features/SemanticTokensProvider';
 import { isNoTextSpanInGeneratedCode, SnapshotFragmentMap } from './features/utils';
 
@@ -367,8 +367,13 @@ export class TypeScriptPlugin
         const doneUpdateProjectFiles = new Set<SnapshotManager>();
 
         for (const { fileName, changeType } of onWatchFileChangesParas) {
-            const scriptKind = getScriptKindFromFileName(fileName);
+            const pathParts = fileName.split(/\/|\\/);
+            const dirPathParts = pathParts.slice(0, pathParts.length - 1);
+            if (ignoredBuildDirectories.some((dir) => dirPathParts.includes(dir))) {
+                continue;
+            }
 
+            const scriptKind = getScriptKindFromFileName(fileName);
             if (scriptKind === ts.ScriptKind.Unknown) {
                 // We don't deal with svelte files here
                 continue;
@@ -382,7 +387,10 @@ export class TypeScriptPlugin
                 }
             } else if (changeType === FileChangeType.Deleted) {
                 snapshotManager.delete(fileName);
-            } else {
+            } else if (snapshotManager.has(fileName)) {
+                // Only allow existing files to be update
+                // Otherwise, new files would still get loaded
+                // into snapshot manager after update
                 snapshotManager.updateTsOrJsFile(fileName);
             }
         }

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

@@ -5,7 +5,7 @@ import { Logger } from '../../logger';
 import { getPackageInfo } from '../../importPackage';
 import { DocumentSnapshot } from './DocumentSnapshot';
 import { createSvelteModuleLoader } from './module-loader';
-import { SnapshotManager } from './SnapshotManager';
+import { ignoredBuildDirectories, SnapshotManager } from './SnapshotManager';
 import { ensureRealSvelteFilePath, findTsConfigPath } from './utils';
 import { configLoader } from '../../lib/documents/configLoader';
 
@@ -269,6 +269,6 @@ async function createLanguageService(
     }
 
     function getDefaultExclude() {
-        return ['__sapper__', 'node_modules'];
+        return ['node_modules', ...ignoredBuildDirectories];
     }
 }

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

@@ -8,6 +8,7 @@ import { LSConfigManager } from '../../../src/ls-config';
 import { TypeScriptPlugin } from '../../../src/plugins';
 import { INITIAL_VERSION } from '../../../src/plugins/typescript/DocumentSnapshot';
 import { pathToUrl, urlToPath } from '../../../src/utils';
+import { ignoredBuildDirectories } from '../../../src/plugins/typescript/SnapshotManager';
 
 describe('TypescriptPlugin', () => {
     function getUri(filename: string) {
@@ -454,6 +455,15 @@ describe('TypescriptPlugin', () => {
             ]);
 
             assert.equal(snapshotManager.has(normalizedAddFilePath), shouldExist);
+
+            await plugin.onWatchFileChanges([
+                {
+                    fileName: normalizedAddFilePath,
+                    changeType: FileChangeType.Changed
+                }
+            ]);
+
+            assert.equal(snapshotManager.has(normalizedAddFilePath), shouldExist);
         } finally {
             fs.unlinkSync(addFile);
         }
@@ -467,6 +477,12 @@ describe('TypescriptPlugin', () => {
         await testForOnWatchedFileAdd(path.join('dist', 'index.js'), false);
     });
 
+    it('should not add snapshot when files added to known build directory', async () => {
+        for (const dir of ignoredBuildDirectories) {
+            await testForOnWatchedFileAdd(path.join(dir, 'index.js'), false);
+        }
+    });
+
     it('should update ts/js file after document change', async () => {
         const {
             snapshotManager,