Prompt selecting a file to save once (#8590)

* Prompt selecting a file to save once
* Better algorithm

Author: DonJayamanne

news/2 Fixes/8138.md

@@ -0,0 +1 @@
+Ensure clicking `ctrl+s` in a new `notebook` prompts the user to select a file once instead of twice.

src/client/datascience/interactive-ipynb/nativeEditor.ts

@@ -83,6 +83,7 @@ export class NativeEditor extends InteractiveBase implements INotebookEditor {
     private loadedPromise: Deferred<void> = createDeferred<void>();
     private _file: Uri = Uri.file('');
     private _dirty: boolean = false;
+    private isPromptingToSaveToDisc: boolean = false;
     private visibleCells: ICell[] = [];
     private startupTimer: StopWatch = new StopWatch();
     private loadedAllCells: boolean = false;
@@ -837,12 +838,18 @@ export class NativeEditor extends InteractiveBase implements INotebookEditor {
 
     @captureTelemetry(Telemetry.Save, undefined, true)
     private async saveToDisk(): Promise<void> {
+        // If we're already in the middle of prompting the user to save, then get out of here.
+        // We could add a debounce decorator, unfortunately that slows saving (by waiting for no more save events to get sent).
+        if (this.isPromptingToSaveToDisc && this.isUntitled) {
+            return;
+        }
         try {
             let fileToSaveTo: Uri | undefined = this.file;
             let isDirty = this._dirty;
 
             // Ask user for a save as dialog if no title
             if (this.isUntitled) {
+                this.isPromptingToSaveToDisc = true;
                 const filtersKey = localize.DataScience.dirtyNotebookDialogFilter();
                 const filtersObject: { [name: string]: string[] } = {};
                 filtersObject[filtersKey] = ['ipynb'];
@@ -865,6 +872,8 @@ export class NativeEditor extends InteractiveBase implements INotebookEditor {
             }
         } catch (e) {
             traceError(e);
+        } finally {
+            this.isPromptingToSaveToDisc = false;
         }
     }