[dotnet-port-fixes] Suppress hosted response emission after cancellation

[github-actions]

Summary

Aligned workflow/agentworkflow hosting with the upstream .NET cancellation fix so a canceled hosted turn stops before emitting the aggregated agent.Response or forwarding final response messages. Added a focused regression test that cancels immediately after the last streamed update and asserts the hosted executor returns context.Canceled without emitting completion artifacts.

Ported .NET PRs

• .NET: Honor cancellation for Foundry-hosted workflow responses agent-framework#7842 - Honor cancellation for Foundry-hosted workflow responses (ce654138fb913a1fd0730e91845a7b5dc4d588a6)

Breaking Changes

No.

Tests and Examples

• go test ./workflow/agentworkflow -run 'TestHostedAgent_(EmitsResponseIfConfigured|CancellationSuppressesFinalResponseEmission)'
• go test ./workflow/agentworkflow

Notes

• This is a behavior-only parity port; it does not change the public Go API.
• The selected upstream change was verified as a fix/test port with no public option, builder, default, or capability change.

Generated by .NET to Go Fixes and Test Porting Agent · gpt54 · 324.2 AIC · ⌖ 15.7 AIC · ⊞ 24.4K · ◷

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Show patch preview (139 of 139 lines)

From c3ba85636f5b098e950a1e242de12cb21386b9ef Mon Sep 17 00:00:00 2001
From: "github-actions[bot]" <github-actions[bot]@users.noreply.github.com>
Date: Fri, 28 Aug 2026 05:14:04 +0000
Subject: [PATCH] [dotnet-port-fixes] Suppress hosted response emission after
 cancellation

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 workflow/agentworkflow/hosting.go      |  5 ++
 workflow/agentworkflow/hosting_test.go | 89 ++++++++++++++++++++++++++
 2 files changed, 94 insertions(+)

diff --git a/workflow/agentworkflow/hosting.go b/workflow/agentworkflow/hosting.go
index b99dd5e28..cdd6192eb 100644
--- a/workflow/agentworkflow/hosting.go
+++ b/workflow/agentworkflow/hosting.go
@@ -430,6 +430,11 @@ func (h *hostExecutor) runAgentAndDispatch(wctx *workflow.Context, messages []*m
 		}
 		resp.Update(update)
 	}
+	// Match .NET hosting: if cancellation arrives after the last streamed update
+	// but before the turn is finalized, do not emit the aggregated completion.
+	if err := wctx.Err(); err != nil {
+		return err
+	}
 	resp.Coalesce()
 
 	// Stamp this hosting executor's name on every aggregated message,
diff --git a/workflow/agentworkflow/hosting_test.go b/workflow/agentworkflow/hosting_test.go
index 5c4b529c0..d20e8265a 100644
--- a/workflow/agentworkflow/hosting_test.go
+++ b/workflow/agentworkflow/hosting_test.go
@@ -175,6 +175,24 @@ func newContentAgent(updates ...*agent.ResponseUpdate) *agent.Agent {
 	)
 }
 
+func newCancelOnCompletionAgent(cancel context.CancelFunc) *agent.Agent {
+	run := func(ctx context.Context, _ []*message.Message, _ ...agent.Option) iter.Seq2[*agent.ResponseUpdate, error] {
+		return func(yield func(*agent.ResponseUpdate, error) bool) {
+			if !yield(&agent.ResponseUpdate{
+				Role:     message.RoleAssistant,
+				Contents: []message.Content{&message.TextContent{Text: "done"}},
+			}, nil) {
+				return
+			}
+			cancel()
+		}
+	}
+	return agent.New(
+		agent.ProviderConfig{ProviderName: "cancel-on-completion", Run: ru
... (truncated)

[michelle-clayton-work]

Pull request #992 is linked to this issue and will close it when merged.