Fix terminal stream stalls after resize

packages/app/src/terminal/runtime/terminal-stream-controller.ts

@@ -40,10 +40,6 @@ export type TerminalStreamControllerOptions = {
 
 const TERMINAL_EXITED_ERROR = "Terminal exited";
 
-function logTerminalStreamController(event: string, details: Record<string, unknown>): void {
-  console.log("[terminal-stream-controller]", event, details);
-}
-
 export class TerminalStreamController {
   private readonly decoder = new TextDecoder();
   private readonly unsubscribeStreamEvents: () => void;
@@ -69,19 +65,10 @@ export class TerminalStreamController {
 
   setTerminal(input: { terminalId: string | null }): void {
     if (this.disposed || input.terminalId === this.terminalId) {
-      logTerminalStreamController("set_terminal_noop", {
-        disposed: this.disposed,
-        currentTerminalId: this.terminalId,
-        requestedTerminalId: input.terminalId,
-      });
       return;
     }
     const nextTerminalId = input.terminalId;
     const previousTerminalId = this.terminalId;
-    logTerminalStreamController("set_terminal", {
-      previousTerminalId,
-      nextTerminalId,
-    });
     this.terminalId = nextTerminalId;
     this.decoder.decode();
     if (previousTerminalId) {
@@ -95,11 +82,6 @@ export class TerminalStreamController {
     void this.options.client
       .subscribeTerminal(nextTerminalId)
       .then((payload) => {
-        logTerminalStreamController("subscribe_resolved", {
-          nextTerminalId,
-          payloadTerminalId: payload.terminalId,
-          error: payload.error ?? null,
-        });
         if (this.disposed || this.terminalId !== nextTerminalId) {
           return;
         }
@@ -113,10 +95,6 @@ export class TerminalStreamController {
           return;
         }
         const preferredSize = this.options.getPreferredSize();
-        logTerminalStreamController("preferred_size_after_subscribe", {
-          nextTerminalId,
-          preferredSize,
-        });
         if (preferredSize) {
           this.options.client.sendTerminalInput(nextTerminalId, {
             type: "resize",
@@ -131,10 +109,6 @@ export class TerminalStreamController {
         });
       })
       .catch((error: unknown) => {
-        logTerminalStreamController("subscribe_rejected", {
-          nextTerminalId,
-          error: error instanceof Error ? error.message : "Unable to subscribe to terminal",
-        });
         if (this.disposed || this.terminalId !== nextTerminalId) {
           return;
         }
@@ -148,10 +122,6 @@ export class TerminalStreamController {
   }
 
   handleTerminalExit(input: { terminalId: string }): void {
-    logTerminalStreamController("terminal_exit", {
-      currentTerminalId: this.terminalId,
-      exitedTerminalId: input.terminalId,
-    });
     if (this.disposed || input.terminalId !== this.terminalId) {
       return;
     }
@@ -168,9 +138,6 @@ export class TerminalStreamController {
     if (this.disposed) {
       return;
     }
-    logTerminalStreamController("dispose", {
-      terminalId: this.terminalId,
-    });
     this.disposed = true;
     this.decoder.decode();
     const terminalId = this.terminalId;

packages/server/src/server/daemon-e2e/terminal.e2e.test.ts

@@ -626,6 +626,45 @@ describe("daemon E2E terminal", () => {
     rmSync(cwd, { recursive: true, force: true });
   }, 30000);
 
+  test("resize does not stall streamed output for an attached client", async () => {
+    const cwd = tmpCwd();
+    const created = await ctx.client.createTerminal(cwd);
+    const terminalId = created.terminal!.id;
+    const secondClient = await connectClient(
+      ctx.daemon.port,
+      `terminal-resize-stream-${Date.now()}-${Math.random().toString(36).slice(2)}`,
+    );
+
+    try {
+      await ctx.client.subscribeTerminal(terminalId);
+      await secondClient.subscribeTerminal(terminalId);
+
+      secondClient.sendTerminalInput(terminalId, {
+        type: "resize",
+        rows: 12,
+        cols: 40,
+      });
+
+      const firstOutput = waitForTerminalOutput(ctx.client, terminalId, (text) =>
+        text.includes("after-resize-stream"),
+      );
+      const secondOutput = waitForTerminalOutput(secondClient, terminalId, (text) =>
+        text.includes("after-resize-stream"),
+      );
+
+      secondClient.sendTerminalInput(terminalId, {
+        type: "input",
+        data: "printf 'after-resize-stream\\n'\r",
+      });
+
+      expect(await firstOutput).toContain("after-resize-stream");
+      expect(await secondOutput).toContain("after-resize-stream");
+    } finally {
+      await secondClient.close();
+      rmSync(cwd, { recursive: true, force: true });
+    }
+  }, 30000);
+
   test("terminal exits notify the client", async () => {
     const cwd = tmpCwd();
     const created = await ctx.client.createTerminal(cwd);

packages/server/src/server/session.ts

@@ -1817,7 +1817,6 @@ export class Session {
         if (!resize) {
           return;
         }
-        activeStream.needsSnapshot = true;
         terminal.send({ type: "resize", rows: resize.rows, cols: resize.cols });
         return;
       }
@@ -7859,6 +7858,7 @@ export class Session {
         this.markAllActiveTerminalStreamsForSnapshot();
       }
     });
+    this.trySendTerminalSnapshot(activeStream);
     return slot;
   }