test(brokeripc): pin the broker client window and document pipe headroom limits

commit: 2d01baf62ae0705be9cff095189b92e02fff36a1
author: brice · 14d ago · 2026-10-08 10:40 UTC
parent: e8bf3a5
signature: GPG VerifiedCD88F9E564E0102646FB6077A1A07C7C7C3E349D · arch-gpg Verified for the committer email

1 file · +14 -3

M internal/adapters/brokeripc/pipe_test.go +14 -3


@@ -112,9 +112,11 @@ func TestStreamPipeCloseWithPreservesQueuedDataOnOrderlyClose(t *testing.T) {
112	112		// TestStreamPipeHoldsAFullOutputWindow pins the client pipe headroom for the
113	113		// session output window. A client claims protocol.MaxOutputWindow unacked
114	114		// Output frames; with a terminal that is not draining, all of them may sit in
115		-	// this pipe at once. Overflow fails the whole stream (ErrStreamBackpressure),
116		-	// so the default bounds must hold that window of worst realistic frames: a
117		-	// near-full repaint of a 500x140 terminal is about 70 KB, i.e. two chunks.
	115	+	// this pipe at once, and overflow fails the whole stream
	116	+	// (ErrStreamBackpressure). The frame size is a typical text repaint: a
	117	+	// near-full page of a 500x140 terminal measured about 70 KB. Uncompressed diff
	118	+	// frames with per-cell truecolor SGR can be far larger (estimated near 1 MB at
	119	+	// 300x80), and eight of those can still overflow the default 4 MiB bound.
118	120		func TestStreamPipeHoldsAFullOutputWindow(t *testing.T) {
119	121		const frameBytes = 72 << 10
120	122		chunk := int(brokerwire.MaxStreamChunkBytes)

@@ -128,3 +130,12 @@ func TestStreamPipeHoldsAFullOutputWindow(t *testing.T) {
128	130		}
129	131		}
130	132		}
	133	+
	134	+	// TestClientStreamPrefersTheFullOutputWindow pins what a real broker-routed
	135	+	// attachment reports: its carriage is a reliable stream, not a datagram link,
	136	+	// so the client claims the full output window and frames pipeline.
	137	+	func TestClientStreamPrefersTheFullOutputWindow(t *testing.T) {
	138	+	st, err := newClientStream(&client{}, 1)
	139	+	require.NoError(t, err)
	140	+	require.Equal(t, uint8(protocol.MaxOutputWindow), st.Capabilities().PreferredOutputWindow)
	141	+	}

 // TestStreamPipeHoldsAFullOutputWindow pins the client pipe headroom for the
 // session output window. A client claims protocol.MaxOutputWindow unacked
 // Output frames; with a terminal that is not draining, all of them may sit in
-// this pipe at once. Overflow fails the whole stream (ErrStreamBackpressure),
+// this pipe at once, and overflow fails the whole stream
-// so the default bounds must hold that window of worst realistic frames: a
+// (ErrStreamBackpressure). The frame size is a typical text repaint: a
-// near-full repaint of a 500x140 terminal is about 70 KB, i.e. two chunks.
+// near-full page of a 500x140 terminal measured about 70 KB. Uncompressed diff
+// frames with per-cell truecolor SGR can be far larger (estimated near 1 MB at
+// 300x80), and eight of those can still overflow the default 4 MiB bound.
 func TestStreamPipeHoldsAFullOutputWindow(t *testing.T) {
 	const frameBytes = 72 << 10
 	chunk := int(brokerwire.MaxStreamChunkBytes)
 		}
 	}
 }
+// TestClientStreamPrefersTheFullOutputWindow pins what a real broker-routed
+// attachment reports: its carriage is a reliable stream, not a datagram link,
+// so the client claims the full output window and frames pipeline.
+func TestClientStreamPrefersTheFullOutputWindow(t *testing.T) {
+	st, err := newClientStream(&client{}, 1)
+	require.NoError(t, err)
+	require.Equal(t, uint8(protocol.MaxOutputWindow), st.Capabilities().PreferredOutputWindow)
+}