test(brokeripc): pin client pipe headroom for a full output window

commit: e8bf3a5f978e34ebe4f009f1da39db77b48c6411
author: brice · 14d ago · 2026-10-08 10:38 UTC
parent: 4fda349
signature: GPG VerifiedCD88F9E564E0102646FB6077A1A07C7C7C3E349D · arch-gpg Verified for the committer email

2 files · +25 -2

M internal/adapters/brokeripc/pipe_test.go +22 -0


@@ -6,6 +6,8 @@ import (
6	6		"io"
7	7		"testing"
8	8
	9	+	"github.com/bnema/vev/internal/adapters/brokerwire"
	10	+	"github.com/bnema/vev/internal/protocol"
9	11		"github.com/stretchr/testify/require"
10	12		)
11	13

@@ -106,3 +108,23 @@ func TestStreamPipeCloseWithPreservesQueuedDataOnOrderlyClose(t *testing.T) {
106	108		})
107	109		}
108	110		}
	111	+
	112	+	// TestStreamPipeHoldsAFullOutputWindow pins the client pipe headroom for the
	113	+	// session output window. A client claims protocol.MaxOutputWindow unacked
	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.
	118	+	func TestStreamPipeHoldsAFullOutputWindow(t *testing.T) {
	119	+	const frameBytes = 72 << 10
	120	+	chunk := int(brokerwire.MaxStreamChunkBytes)
	121	+	p := newStreamPipe(0, 0, func([]byte) error { return nil })
	122	+	payload := bytes.Repeat([]byte{'x'}, frameBytes)
	123	+	for frame := range protocol.MaxOutputWindow {
	124	+	for data := payload; len(data) > 0; {
	125	+	n := min(len(data), chunk)
	126	+	require.NoError(t, p.deliver(data[:n]), "frame %d overflowed the client pipe", frame)
	127	+	data = data[n:]
	128	+	}
	129	+	}
	130	+	}


@@ -6,6 +6,8 @@ import (
6	"io"	6		"io"
7	"testing"	7		"testing"
8		8
		9	+	"github.com/bnema/vev/internal/adapters/brokerwire"
		10	+	"github.com/bnema/vev/internal/protocol"
9	"github.com/stretchr/testify/require"	11		"github.com/stretchr/testify/require"
10	)	12		)
11		13

@@ -106,3 +108,23 @@ func TestStreamPipeCloseWithPreservesQueuedDataOnOrderlyClose(t *testing.T) {
106	})	108		})
107	}	109		}
108	}	110		}
		111	+
		112	+	// TestStreamPipeHoldsAFullOutputWindow pins the client pipe headroom for the
		113	+	// session output window. A client claims protocol.MaxOutputWindow unacked
		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.
		118	+	func TestStreamPipeHoldsAFullOutputWindow(t *testing.T) {
		119	+	const frameBytes = 72 << 10
		120	+	chunk := int(brokerwire.MaxStreamChunkBytes)
		121	+	p := newStreamPipe(0, 0, func([]byte) error { return nil })
		122	+	payload := bytes.Repeat([]byte{'x'}, frameBytes)
		123	+	for frame := range protocol.MaxOutputWindow {
		124	+	for data := payload; len(data) > 0; {
		125	+	n := min(len(data), chunk)
		126	+	require.NoError(t, p.deliver(data[:n]), "frame %d overflowed the client pipe", frame)
		127	+	data = data[n:]
		128	+	}
		129	+	}
		130	+	}

M internal/usecase/client/runtime_primitives_test.go +3 -2


@@ -35,8 +35,9 @@ func TestRequestedOutputWindow(t *testing.T) {
35	35		}
36	36		}
37	37
38		-	// TestHelloRequestsPipelinedOutput pins the window a real attachment Hello
39		-	// asks for. A window of one would make every remote frame wait a round trip.
	38	+	// TestHelloRequestsPipelinedOutput pins the fallback window an attachment
	39	+	// Hello claims when its carriage states no preference. A window of one would
	40	+	// make every remote frame wait a round trip.
40	41		func TestHelloRequestsPipelinedOutput(t *testing.T) {
41	42		worker, err := newSessionAttachmentWorker(sessionAttachmentConfig{Request: sessionTestRequest(false), SessionEnvironment: SessionEnvironment{Provenance: SessionEnvironmentRemote}})
42	43		require.NoError(t, err)

 	}
 }
-// TestHelloRequestsPipelinedOutput pins the window a real attachment Hello
+// TestHelloRequestsPipelinedOutput pins the fallback window an attachment
-// asks for. A window of one would make every remote frame wait a round trip.
+// Hello claims when its carriage states no preference. A window of one would
+// make every remote frame wait a round trip.
 func TestHelloRequestsPipelinedOutput(t *testing.T) {
 	worker, err := newSessionAttachmentWorker(sessionAttachmentConfig{Request: sessionTestRequest(false), SessionEnvironment: SessionEnvironment{Provenance: SessionEnvironmentRemote}})
 	require.NoError(t, err)