Keep scriptInfo and project alive even after file delete till next file open

src/harness/projectServiceStateLogger.ts

@@ -13,6 +13,7 @@ import {
 import {
     AutoImportProviderProject,
     AuxiliaryProject,
+    ConfiguredProject,
     isBackgroundProject,
     isConfiguredProject,
     LogLevel,
@@ -32,6 +33,7 @@ interface ProjectData {
     isClosed: ReturnType<Project["isClosed"]>;
     isOrphan: ReturnType<Project["isOrphan"]>;
     noOpenRef: boolean;
+    deferredClose: ConfiguredProject["deferredClose"];
     documentPositionMappers: SourceMapper["documentPositionMappers"];
     autoImportProviderHost: Project["autoImportProviderHost"];
     noDtsResolutionProject: Project["noDtsResolutionProject"];
@@ -46,6 +48,7 @@ interface ScriptInfoData {
     open: ReturnType<ScriptInfo["isScriptOpen"]>;
     version: ReturnType<TextStorage["getVersion"]>;
     pendingReloadFromDisk: TextStorage["pendingReloadFromDisk"];
+    deferredDelete: ScriptInfo["deferredDelete"];
     sourceMapFilePath: Exclude<ScriptInfo["sourceMapFilePath"], SourceMapFileWatcher> | SourceMapFileWatcherData | undefined;
     declarationInfoPath: ScriptInfo["declarationInfoPath"];
     sourceInfos: ScriptInfo["sourceInfos"];
@@ -116,6 +119,7 @@ export function patchServiceForStateBaseline(service: ProjectService) {
                 projectDiff = printProperty(PrintPropertyWhen.TruthyOrChangedOrNew, data, "isClosed", project.isClosed(), projectDiff, projectPropertyLogs);
                 projectDiff = printProperty(PrintPropertyWhen.TruthyOrChangedOrNew, data, "isOrphan", !isBackgroundProject(project) && project.isOrphan(), projectDiff, projectPropertyLogs);
                 projectDiff = printProperty(PrintPropertyWhen.TruthyOrChangedOrNew, data, "noOpenRef", isConfiguredProject(project) && !project.hasOpenRef(), projectDiff, projectPropertyLogs);
+                projectDiff = printProperty(PrintPropertyWhen.TruthyOrChangedOrNew, data, "deferredClose", isConfiguredProject(project) && project.deferredClose, projectDiff, projectPropertyLogs);
                 projectDiff = printMapPropertyValue(
                     PrintPropertyWhen.Changed,
                     data?.documentPositionMappers,
@@ -146,6 +150,7 @@ export function patchServiceForStateBaseline(service: ProjectService) {
                 isClosed: project.isClosed(),
                 isOrphan: !isBackgroundProject(project) && project.isOrphan(),
                 noOpenRef: isConfiguredProject(project) && !project.hasOpenRef(),
+                deferredClose: isConfiguredProject(project) && project.deferredClose,
                 autoImportProviderHost: project.autoImportProviderHost,
                 noDtsResolutionProject: project.noDtsResolutionProject,
                 originalConfiguredProjects: project.originalConfiguredProjects && new Set(project.originalConfiguredProjects),
@@ -166,6 +171,7 @@ export function patchServiceForStateBaseline(service: ProjectService) {
                 infoDiff = printProperty(PrintPropertyWhen.Changed, data, "open", isOpen, infoDiff, infoPropertyLogs);
                 infoDiff = printProperty(PrintPropertyWhen.Always, data, "version", info.textStorage.getVersion(), infoDiff, infoPropertyLogs);
                 infoDiff = printProperty(PrintPropertyWhen.TruthyOrChangedOrNew, data, "pendingReloadFromDisk", info.textStorage.pendingReloadFromDisk, infoDiff, infoPropertyLogs);
+                infoDiff = printProperty(PrintPropertyWhen.TruthyOrChangedOrNew, data, "deferredDelete", info.deferredDelete, infoDiff, infoPropertyLogs);
                 infoDiff = printScriptInfoSourceMapFilePath(data, info, infoDiff, infoPropertyLogs);
                 infoDiff = printProperty(PrintPropertyWhen.DefinedOrChangedOrNew, data, "declarationInfoPath", info.declarationInfoPath, infoDiff, infoPropertyLogs);
                 infoDiff = printSetPropertyValueWorker(PrintPropertyWhen.DefinedOrChangedOrNew, data?.sourceInfos, "sourceInfos", info.sourceInfos, infoDiff, infoPropertyLogs, identity);
@@ -200,6 +206,7 @@ export function patchServiceForStateBaseline(service: ProjectService) {
                 sourceInfos: info.sourceInfos && new Set(info.sourceInfos),
                 documentPositionMapper: info.documentPositionMapper,
                 containingProjects: new Set(info.containingProjects),
+                deferredDelete: info.deferredDelete,
             }),
         );
     }

src/server/project.ts

@@ -657,7 +657,12 @@ export abstract class Project implements LanguageServiceHost, ModuleResolutionHo
     }
 
     private getOrCreateScriptInfoAndAttachToProject(fileName: string) {
-        const scriptInfo = this.projectService.getOrCreateScriptInfoNotOpenedByClient(fileName, this.currentDirectory, this.directoryStructureHost);
+        const scriptInfo = this.projectService.getOrCreateScriptInfoNotOpenedByClient(
+            fileName,
+            this.currentDirectory,
+            this.directoryStructureHost,
+            /*deferredDeleteOk*/ false,
+        );
         if (scriptInfo) {
             const existingValue = this.rootFilesMap.get(scriptInfo.path);
             if (existingValue && existingValue.info !== scriptInfo) {
@@ -678,7 +683,12 @@ export abstract class Project implements LanguageServiceHost, ModuleResolutionHo
     getScriptVersion(filename: string) {
         // Don't attach to the project if version is asked
 
-        const info = this.projectService.getOrCreateScriptInfoNotOpenedByClient(filename, this.currentDirectory, this.directoryStructureHost);
+        const info = this.projectService.getOrCreateScriptInfoNotOpenedByClient(
+            filename,
+            this.currentDirectory,
+            this.directoryStructureHost,
+            /*deferredDeleteOk*/ false,
+        );
         return (info && info.getLatestVersion())!; // TODO: GH#18217
     }
 
@@ -1298,6 +1308,7 @@ export abstract class Project implements LanguageServiceHost, ModuleResolutionHo
         }
     }
 
+    /** @internal */
     markAsDirty() {
         if (!this.dirty) {
             this.projectStateVersion++;
@@ -1658,7 +1669,12 @@ export abstract class Project implements LanguageServiceHost, ModuleResolutionHo
             // by the host for files in the program when the program is retrieved above but
             // the program doesn't contain external files so this must be done explicitly.
             inserted => {
-                const scriptInfo = this.projectService.getOrCreateScriptInfoNotOpenedByClient(inserted, this.currentDirectory, this.directoryStructureHost);
+                const scriptInfo = this.projectService.getOrCreateScriptInfoNotOpenedByClient(
+                    inserted,
+                    this.currentDirectory,
+                    this.directoryStructureHost,
+                    /*deferredDeleteOk*/ false,
+                );
                 scriptInfo?.attachToProject(this);
             },
             removed => this.detachScriptInfoFromProject(removed),
@@ -2584,6 +2600,7 @@ export class AutoImportProviderProject extends Project {
         return !some(this.rootFileNames);
     }
 
+    /** @internal */
     override isOrphan() {
         return true;
     }
@@ -2619,6 +2636,7 @@ export class AutoImportProviderProject extends Project {
         return !!this.rootFileNames?.length;
     }
 
+    /** @internal */
     override markAsDirty() {
         this.rootFileNames = undefined;
         super.markAsDirty();
@@ -2713,6 +2731,9 @@ export class ConfiguredProject extends Project {
     /** @internal */
     skipConfigDiagEvent?: true;
 
+    /** @internal */
+    deferredClose?: boolean;
+
     /** @internal */
     constructor(
         configFileName: NormalizedPath,
@@ -2773,6 +2794,7 @@ export class ConfiguredProject extends Project {
      * @returns: true if set of files in the project stays the same and false - otherwise.
      */
     override updateGraph(): boolean {
+        if (this.deferredClose) return false;
         const isInitialLoad = this.isInitialLoadPending();
         this.isInitialLoadPending = returnFalse;
         const updateLevel = this.pendingUpdateLevel;
@@ -2892,6 +2914,12 @@ export class ConfiguredProject extends Project {
         super.close();
     }
 
+    /** @internal */
+    override markAsDirty() {
+        if (this.deferredClose) return;
+        super.markAsDirty();
+    }
+
     /** @internal */
     addExternalProjectReference() {
         this.externalProjectRefCount++;
@@ -2941,6 +2969,7 @@ export class ConfiguredProject extends Project {
         }
 
         const configFileExistenceInfo = this.projectService.configFileExistenceInfoCache.get(this.canonicalConfigFilePath)!;
+        if (this.deferredClose) return !!configFileExistenceInfo.openFilesImpactedByConfigFile?.size;
         if (this.projectService.hasPendingProjectUpdate(this)) {
             // If there is pending update for this project,
             // we dont know if this project would be needed by any of the open files impacted by this config file
@@ -2966,6 +2995,11 @@ export class ConfiguredProject extends Project {
                 ) || false;
     }
 
+    /** @internal */
+    override isOrphan(): boolean {
+        return !!this.deferredClose;
+    }
+
     /** @internal */
     hasExternalProjectRef() {
         return !!this.externalProjectRefCount;
@@ -3023,3 +3057,8 @@ export function isExternalProject(project: Project): project is ExternalProject
 export function isBackgroundProject(project: Project): project is AutoImportProviderProject | AuxiliaryProject {
     return project.projectKind === ProjectKind.AutoImportProvider || project.projectKind === ProjectKind.Auxiliary;
 }
+
+/** @internal */
+export function isProjectDeferredClose(project: Project): project is ConfiguredProject {
+    return isConfiguredProject(project) && !!project.deferredClose;
+}

src/server/scriptInfo.ts

@@ -25,6 +25,7 @@ import {
     IScriptSnapshot,
     isString,
     LineInfo,
+    missingFileModifiedTime,
     orderedRemoveItem,
     Path,
     ScriptKind,
@@ -44,6 +45,7 @@ import {
     isConfiguredProject,
     isExternalProject,
     isInferredProject,
+    isProjectDeferredClose,
     maxFileSize,
     NormalizedPath,
     Project,
@@ -180,6 +182,14 @@ export class TextStorage {
         const reloaded = this.reload(newText);
         this.fileSize = fileSize; // NB: after reload since reload clears it
         this.ownFileText = !tempFileName || tempFileName === this.info.fileName;
+        // In case we update this text before mTime gets updated to present file modified time
+        // because its schedule to do that later, update the mTime so we dont re-update the text
+        // Eg. with npm ci where file gets created and editor calls say get error request before
+        // the timeout to update the file stamps in node_modules is run
+        // Test:: watching npm install in codespaces where workspaces folder is hosted at root
+        if (this.ownFileText && this.info.mTime === missingFileModifiedTime.getTime()) {
+            this.info.mTime = (this.host.getModifiedTime!(this.info.fileName) || missingFileModifiedTime).getTime();
+        }
         return reloaded;
     }
 
@@ -398,6 +408,9 @@ export class ScriptInfo {
     /** @internal */
     documentPositionMapper?: DocumentPositionMapper | false;
 
+    /** @internal */
+    deferredDelete?: boolean;
+
     constructor(
         private readonly host: ServerHost,
         readonly fileName: NormalizedPath,
@@ -567,7 +580,10 @@ export class ScriptInfo {
             case 0:
                 return Errors.ThrowNoProject();
             case 1:
-                return ensurePrimaryProjectKind(this.containingProjects[0]);
+                return ensurePrimaryProjectKind(
+                    !isProjectDeferredClose(this.containingProjects[0]) ?
+                        this.containingProjects[0] : undefined,
+                );
             default:
                 // If this file belongs to multiple projects, below is the order in which default project is used
                 // - for open script info, its default configured project during opening is default if info is part of it
@@ -583,6 +599,7 @@ export class ScriptInfo {
                 for (let index = 0; index < this.containingProjects.length; index++) {
                     const project = this.containingProjects[index];
                     if (isConfiguredProject(project)) {
+                        if (project.deferredClose) continue;
                         if (!project.isSourceOfProjectReferenceRedirect(this.fileName)) {
                             // If we havent found default configuredProject and
                             // its not the last one, find it and use that one if there
@@ -676,7 +693,7 @@ export class ScriptInfo {
     }
 
     isOrphan() {
-        return !forEach(this.containingProjects, p => !p.isOrphan());
+        return this.deferredDelete || !forEach(this.containingProjects, p => !p.isOrphan());
     }
 
     /** @internal */

src/server/session.ts

@@ -1575,6 +1575,7 @@ export class Session<TMessage = string> implements EventSender {
                         fileNameToSearch,
                         noDtsProject.currentDirectory,
                         noDtsProject.directoryStructureHost,
+                        /*deferredDeleteOk*/ false,
                     );
                     if (!info) continue;
                     if (!noDtsProject.containsScriptInfo(info)) {