From 5deab9f721d6ddd3825a5cb01bb0279ba2e005e4 Mon Sep 17 00:00:00 2001
From: Danielle Maywood <danielle@themaywoods.com>
Date: Fri, 22 May 2026 13:55:21 +0100
Subject: [PATCH] test: wait for devcontainer readiness (#25567)

---
 cli/open_test.go                | 67 ++++++++++++++++++++++++++++++++-
 coderd/coderdtest/coderdtest.go | 16 ++++++++
 coderd/workspaceapps/db_test.go | 13 +------
 3 files changed, 84 insertions(+), 12 deletions(-)

diff --git a/cli/open_test.go b/cli/open_test.go
index 595bb2f1ce..564fbe657a 100644
--- a/cli/open_test.go
+++ b/cli/open_test.go
@@ -433,7 +433,72 @@ func TestOpenVSCodeDevContainer(t *testing.T) {
 			agentcontainers.WithContainerLabelIncludeFilter("coder.test", t.Name()),
 		)
 	})
-	coderdtest.NewWorkspaceAgentWaiter(t, client, workspace.ID).AgentNames([]string{parentAgentName, devcontainerName}).Wait()
+	resources := coderdtest.NewWorkspaceAgentWaiter(t, client, workspace.ID).AgentNames([]string{parentAgentName}).Wait()
+	parentAgent := coderdtest.RequireWorkspaceAgentByName(t, resources, parentAgentName)
+	parentAgentID := parentAgent.ID
+
+	// Agent connection does not guarantee the parent agent's container API
+	// has completed its first devcontainer update. Wait for that endpoint so
+	// parallel open commands do not race the initial cache population.
+	ctx := testutil.Context(t, testutil.WaitSuperLong)
+	testutil.Eventually(ctx, t, func(ctx context.Context) bool {
+		resp, err := client.WorkspaceAgentListContainers(ctx, parentAgentID, nil)
+		if err != nil {
+			t.Logf("list containers: %v", err)
+			return false
+		}
+		var devcontainerAgentID uuid.UUID
+		for _, dc := range resp.Devcontainers {
+			if dc.ID != devcontainerID {
+				continue
+			}
+			if dc.Status != codersdk.WorkspaceAgentDevcontainerStatusRunning {
+				t.Logf("devcontainer %s status %q", devcontainerName, dc.Status)
+				return false
+			}
+			if dc.Container == nil {
+				t.Logf("devcontainer %s missing container", devcontainerName)
+				return false
+			}
+			if dc.Container.ID != containerID {
+				t.Logf("devcontainer %s has container %s, want %s", devcontainerName, dc.Container.ID, containerID)
+				return false
+			}
+			if dc.Agent == nil {
+				t.Logf("devcontainer %s missing subagent", devcontainerName)
+				return false
+			}
+			if dc.Agent.Name != devcontainerName {
+				t.Logf("devcontainer %s has subagent %s, want %s", devcontainerName, dc.Agent.Name, devcontainerName)
+				return false
+			}
+			devcontainerAgentID = dc.Agent.ID
+		}
+		if devcontainerAgentID == uuid.Nil {
+			t.Logf("devcontainer %s not found", devcontainerName)
+			return false
+		}
+
+		workspace, err := client.Workspace(ctx, workspace.ID)
+		if err != nil {
+			t.Logf("get workspace: %v", err)
+			return false
+		}
+		for _, resource := range workspace.LatestBuild.Resources {
+			for _, workspaceAgent := range resource.Agents {
+				if workspaceAgent.ID != devcontainerAgentID {
+					continue
+				}
+				if workspaceAgent.Status != codersdk.WorkspaceAgentConnected {
+					t.Logf("devcontainer subagent %s status %q", devcontainerAgentID, workspaceAgent.Status)
+					return false
+				}
+				return true
+			}
+		}
+		t.Logf("devcontainer subagent %s not found in workspace", devcontainerAgentID)
+		return false
+	}, testutil.IntervalMedium, "devcontainer did not become ready")
 
 	insideWorkspaceEnv := map[string]string{
 		"CODER":                      "true",
diff --git a/coderd/coderdtest/coderdtest.go b/coderd/coderdtest/coderdtest.go
index e62b201252..ab8d2271c3 100644
--- a/coderd/coderdtest/coderdtest.go
+++ b/coderd/coderdtest/coderdtest.go
@@ -1278,6 +1278,22 @@ func NewWorkspaceAgentWaiter(t testing.TB, client *codersdk.Client, workspaceID
 	}
 }
 
+// RequireWorkspaceAgentByName avoids weak nil UUID assertions when a fixture requires a specific agent.
+func RequireWorkspaceAgentByName(t testing.TB, resources []codersdk.WorkspaceResource, name string) codersdk.WorkspaceAgent {
+	t.Helper()
+
+	for _, resource := range resources {
+		for _, agent := range resource.Agents {
+			if agent.Name == name {
+				return agent
+			}
+		}
+	}
+
+	require.FailNowf(t, "workspace agent not found", "workspace agent %q not found in resources", name)
+	return codersdk.WorkspaceAgent{}
+}
+
 // AgentNames instructs the waiter to wait for the given, named agents to be connected and will
 // return even if other agents are not connected.
 func (w WorkspaceAgentWaiter) AgentNames(names []string) WorkspaceAgentWaiter {
diff --git a/coderd/workspaceapps/db_test.go b/coderd/workspaceapps/db_test.go
index d59160f1b5..1631c7d403 100644
--- a/coderd/workspaceapps/db_test.go
+++ b/coderd/workspaceapps/db_test.go
@@ -218,17 +218,8 @@ func Test_ResolveRequest(t *testing.T) {
 
 	_ = agenttest.New(t, client.URL, agentAuthToken)
 	resources := coderdtest.AwaitWorkspaceAgents(t, client, workspace.ID, agentName)
-
-	agentID := uuid.Nil
-	for _, resource := range resources {
-		for _, agnt := range resource.Agents {
-			if agnt.Name == agentName {
-				agentID = agnt.ID
-				break
-			}
-		}
-	}
-	require.NotEqual(t, uuid.Nil, agentID)
+	agent := coderdtest.RequireWorkspaceAgentByName(t, resources, agentName)
+	agentID := agent.ID
 
 	// Reset audit logs so cleanup check can pass.
 	connLogger.Reset()