fix: only create a new file if parent dir exists

This also fixes a bug where in a non-directory file, the back button
moves the user back two directories.

cmd/wsh/cmd/wshcmd-view.go

@@ -4,6 +4,8 @@
 package cmd
 
 import (
+	"io/fs"
+	"os"
 	"path/filepath"
 	"strings"
 
@@ -56,6 +58,20 @@ func viewRun(cmd *cobra.Command, args []string) {
 			WriteStderr("[error] getting absolute path: %v\n", err)
 			return
 		}
+		absParent, err := filepath.Abs(filepath.Dir(fileArg))
+		if err != nil {
+			WriteStderr("[error] getting absolute path of parent dir: %v\n", err)
+			return
+		}
+		_, err = os.Stat(absParent)
+		if err == fs.ErrNotExist {
+			WriteStderr("[error] parent directory does not exist: %q\n", absParent)
+			return
+		}
+		if err != nil {
+			WriteStderr("[error] getting file info: %v\n", err)
+			return
+		}
 		wshCmd = &wshrpc.CommandCreateBlockData{
 			BlockDef: &waveobj.BlockDef{
 				Meta: map[string]interface{}{

frontend/app/view/preview/preview.tsx

@@ -432,7 +432,12 @@ export class PreviewModel implements ViewModel {
         const fileInfo = await getFn(this.statFile);
         const fileName = await getFn(this.statFilePath);
         const editMode = getFn(this.editMode);
+        const parentFileInfo = await this.getParentInfo(fileInfo);
+        console.log(parentFileInfo);
 
+        if (parentFileInfo?.notfound ?? false) {
+            return { errorStr: `Parent Directory Not Found: ${fileInfo.path}` };
+        }
         if (fileInfo?.notfound) {
             return { specializedView: "codeedit" };
         }
@@ -492,6 +497,18 @@ export class PreviewModel implements ViewModel {
         services.ObjectService.UpdateObjectMeta(blockOref, updateMeta);
     }
 
+    async getParentInfo(fileInfo: FileInfo): Promise<FileInfo | undefined> {
+        const conn = globalStore.get(this.connection);
+        try {
+            const parentFileInfo = await RpcApi.RemoteFileJoinCommand(WindowRpcClient, [fileInfo.path, ".."], {
+                route: makeConnRoute(conn),
+            });
+            return parentFileInfo;
+        } catch {
+            return undefined;
+        }
+    }
+
     async goParentDirectory() {
         const fileInfo = await globalStore.get(this.statFile);
         if (fileInfo == null) {
@@ -500,7 +517,7 @@ export class PreviewModel implements ViewModel {
         }
         const conn = globalStore.get(this.connection);
         try {
-            const newFileInfo = await RpcApi.RemoteFileJoinCommand(WindowRpcClient, [fileInfo.dir, ".."], {
+            const newFileInfo = await RpcApi.RemoteFileJoinCommand(WindowRpcClient, [fileInfo.path, ".."], {
                 route: makeConnRoute(conn),
             });
             console.log(newFileInfo.path);