feat: add support for --watch flag

README.md

@@ -48,6 +48,7 @@ You can configure the extension using the following settings:
 - `marimo.browserType`: Browser to open marimo app (`system` or `embedded`, default: `embedded`)
 - `marimo.port`: Default port for marimo server (default: `2818`)
 - `marimo.sandbox`: Always start marimo in a sandbox, e.g. `marimo edit --sandbox` (default: `false`). Requires [`uv`](https://docs.astral.sh/uv/) to be installed.
+- `marimo.watch`: Always start marimo with the `--watch` flag (default: `true`).
 - `marimo.host`: Hostname for marimo server (default: `localhost`)
 - `marimo.https`: Enable HTTPS for marimo server (default: `false`)
 - `marimo.enableToken`: Enable token authentication (default: `false`)

package.json

@@ -336,6 +336,11 @@
           "default": false,
           "description": "Whether to always start marimo in a sandbox. Requires `uv` to be installed."
         },
+        "marimo.watch": {
+          "type": "boolean",
+          "default": true,
+          "description": "Whether to always start marimo with the --watch flag."
+        },
         "marimo.https": {
           "type": "boolean",
           "default": false,

src/config.ts

@@ -21,6 +21,7 @@ export interface Config {
   readonly tokenPassword: string | undefined;
   readonly https: boolean;
   readonly sandbox: boolean;
+  readonly watch: boolean;
 }
 
 /**
@@ -131,6 +132,14 @@ export const Config = {
   get sandbox(): boolean {
     return getConfig("sandbox", false);
   },
+
+  /**
+   * Whether to always start marimo with the --watch flag.
+   * @default true
+   */
+  get watch(): boolean {
+    return getConfig("watch", true);
+  },
 };
 
 export async function composeUrl(port: number): Promise<string> {

src/services/server-manager.ts

@@ -283,6 +283,7 @@ export class ServerManager implements IServerManager {
       .enableToken(this.config.enableToken)
       .tokenPassword(this.config.tokenPassword)
       .sandbox(this.config.sandbox)
+      .watch(this.config.watch)
       .build();
   }
 

src/utils/__tests__/cmd.test.ts

@@ -105,4 +105,20 @@ describe("MarimoCmdBuilder", () => {
       `"marimo --yes edit path/to/file --host=localhost --port=2718 --headless --no-token --sandbox"`,
     );
   });
+
+  it("should support watch mode", () => {
+    const cmd = new MarimoCmdBuilder()
+      .debug(false)
+      .mode("edit")
+      .fileOrDir("path/to/file")
+      .host("localhost")
+      .port(2718)
+      .headless(true)
+      .enableToken(false)
+      .watch(true)
+      .build();
+    expect(cmd).toMatchInlineSnapshot(
+      `"marimo --yes edit path/to/file --host=localhost --port=2718 --headless --no-token --watch"`,
+    );
+  });
 });

src/utils/cmd.ts

@@ -64,6 +64,13 @@ export class MarimoCmdBuilder {
     return this;
   }
 
+  watch(value: boolean) {
+    if (value) {
+      this.cmd.push("--watch");
+    }
+    return this;
+  }
+
   build() {
     return this.cmd.join(" ");
   }