Improve error message when scriptInfo is missing in mapTextChangeToCodeEdit

src/server/editorServices.ts

@@ -867,7 +867,13 @@ namespace ts.server {
         private doEnsureDefaultProjectForFile(fileName: NormalizedPath): Project {
             this.ensureProjectStructuresUptoDate();
             const scriptInfo = this.getScriptInfoForNormalizedPath(fileName);
-            return scriptInfo ? scriptInfo.getDefaultProject() : Errors.ThrowNoProject();
+            if (scriptInfo) {
+                return scriptInfo.getDefaultProject();
+            }
+            else {
+                this.logger.msg(`Cannot find ${fileName} in ${JSON.stringify(this.allScriptInfoFileNamesForDebug)}`, Msg.Err);
+                return Errors.ThrowNoProject();
+            }
         }
 
         getScriptInfoEnsuringProjectsUptoDate(uncheckedFileName: string) {
@@ -1966,6 +1972,15 @@ namespace ts.server {
             return configProject && configProject.getCompilerOptions().configFile;
         }
 
+        /* @internal */
+        allScriptInfoFileNamesForDebug(): ReadonlyArray<{ readonly path: string, readonly fileName: string }> {
+            const out: { readonly path: string, readonly fileName: string }[] = [];
+            this.filenameToScriptInfo.forEach((scriptInfo, path) => {
+                out.push({ path, fileName: scriptInfo.fileName });
+            });
+            return out;
+        }
+
         /**
          * Returns the projects that contain script info through SymLink
          * Note that this does not return projects in info.containingProjects

src/server/session.ts

@@ -1157,19 +1157,27 @@ namespace ts.server {
                     this.projectService.getScriptInfoEnsuringProjectsUptoDate(args.file) :
                     this.projectService.getScriptInfo(args.file);
                 if (!scriptInfo) {
-                    return ignoreNoProjectError ? emptyArray : Errors.ThrowNoProject();
+                    if (ignoreNoProjectError) return emptyArray;
+                    this.logErrorForScriptInfoNotFound(args.file);
+                    return Errors.ThrowNoProject();
                 }
                 projects = scriptInfo.containingProjects;
                 symLinkedProjects = this.projectService.getSymlinkedProjects(scriptInfo);
             }
             // filter handles case when 'projects' is undefined
             projects = filter(projects, p => p.languageServiceEnabled && !p.isOrphan());
             if (!ignoreNoProjectError && (!projects || !projects.length) && !symLinkedProjects) {
+                this.logErrorForScriptInfoNotFound(args.file);
                 return Errors.ThrowNoProject();
             }
             return symLinkedProjects ? { projects: projects!, symLinkedProjects } : projects!; // TODO: GH#18217
         }
 
+        private logErrorForScriptInfoNotFound(fileName: string): void {
+            this.logger.msg(`Could not find file ${JSON.stringify(fileName)}.\n` +
+                `All files are: ${JSON.stringify(this.projectService.allScriptInfoFileNamesForDebug())}`, Msg.Err);
+        }
+
         private getDefaultProject(args: protocol.FileRequestArgs) {
             if (args.projectFileName) {
                 const project = this.getProject(args.projectFileName);
@@ -1908,8 +1916,17 @@ namespace ts.server {
             return textChanges.map(change => this.mapTextChangeToCodeEdit(change));
         }
 
-        private mapTextChangeToCodeEdit(change: FileTextChanges): protocol.FileCodeEdits {
-            return mapTextChangesToCodeEdits(change, this.projectService.getScriptInfoOrConfig(change.fileName));
+        private mapTextChangeToCodeEdit(textChanges: FileTextChanges): protocol.FileCodeEdits {
+            const scriptInfo = this.projectService.getScriptInfoOrConfig(textChanges.fileName);
+            if (!!textChanges.isNewFile === !!scriptInfo) {
+                if (!scriptInfo) { // and !isNewFile
+                    this.logErrorForScriptInfoNotFound(textChanges.fileName);
+                }
+                Debug.fail("Expected isNewFile for (only) new files. " + JSON.stringify({ isNewFile: !!textChanges.isNewFile, hasScriptInfo: !!scriptInfo }));
+            }
+            return scriptInfo
+                ? { fileName: textChanges.fileName, textChanges: textChanges.textChanges.map(textChange => convertTextChangeToCodeEdit(textChange, scriptInfo)) }
+                : convertNewFileTextChangeToCodeEdit(textChanges);
         }
 
         private convertTextChangeToCodeEdit(change: TextChange, scriptInfo: ScriptInfo): protocol.CodeEdit {
@@ -2431,13 +2448,6 @@ namespace ts.server {
         return { file: fileName, start: scriptInfo.positionToLineOffset(textSpan.start), end: scriptInfo.positionToLineOffset(textSpanEnd(textSpan)) };
     }
 
-    function mapTextChangesToCodeEdits(textChanges: FileTextChanges, scriptInfo: ScriptInfoOrConfig | undefined): protocol.FileCodeEdits {
-        Debug.assert(!!textChanges.isNewFile === !scriptInfo, "Expected isNewFile for (only) new files", () => JSON.stringify({ isNewFile: !!textChanges.isNewFile, hasScriptInfo: !!scriptInfo }));
-        return scriptInfo
-            ? { fileName: textChanges.fileName, textChanges: textChanges.textChanges.map(textChange => convertTextChangeToCodeEdit(textChange, scriptInfo)) }
-            : convertNewFileTextChangeToCodeEdit(textChanges);
-    }
-
     function convertTextChangeToCodeEdit(change: TextChange, scriptInfo: ScriptInfoOrConfig): protocol.CodeEdit {
         return { start: positionToLineOffset(scriptInfo, change.span.start), end: positionToLineOffset(scriptInfo, textSpanEnd(change.span)), newText: change.newText };
     }

tests/baselines/reference/api/tsserverlibrary.d.ts

@@ -8826,6 +8826,7 @@ declare namespace ts.server {
         private getProjectInfoWorker;
         private getRenameInfo;
         private getProjects;
+        private logErrorForScriptInfoNotFound;
         private getDefaultProject;
         private getRenameLocations;
         private mapRenameInfo;