PSS: Migration from a backend to a state store

internal/backend/remote-state/inmem/backend.go

@@ -71,22 +71,27 @@ func (b *Backend) Configure(configVal cty.Value) tfdiags.Diagnostics {
 	states.Lock()
 	defer states.Unlock()
 
-	defaultClient := &RemoteClient{
-		Name: backend.DefaultStateName,
-	}
+	// Some tests may configure this backend multiple times
+	// and expect the same state from memory afterwards.
+	_, ok := states.m[backend.DefaultStateName]
+	if !ok {
+		defaultClient := &RemoteClient{
+			Name: backend.DefaultStateName,
+		}
 
-	states.m[backend.DefaultStateName] = &remote.State{
-		Client: defaultClient,
-	}
+		states.m[backend.DefaultStateName] = &remote.State{
+			Client: defaultClient,
+		}
 
-	// set the default client lock info per the test config
-	if v := configVal.GetAttr("lock_id"); !v.IsNull() {
-		info := statemgr.NewLockInfo()
-		info.ID = v.AsString()
-		info.Operation = "test"
-		info.Info = "test config"
+		// set the default client lock info per the test config
+		if v := configVal.GetAttr("lock_id"); !v.IsNull() {
+			info := statemgr.NewLockInfo()
+			info.ID = v.AsString()
+			info.Operation = "test"
+			info.Info = "test config"
 
-		locks.lock(backend.DefaultStateName, info)
+			locks.lock(backend.DefaultStateName, info)
+		}
 	}
 
 	return nil

internal/backend/remote-state/inmem/testing.go

@@ -0,0 +1,34 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: BUSL-1.1
+
+package inmem
+
+import (
+	"testing"
+
+	statespkg "github.com/hashicorp/terraform/internal/states"
+)
+
+func ReadState(t *testing.T, wsName string) *statespkg.State {
+	states.Lock()
+	defer states.Unlock()
+
+	stateMgr, ok := states.m[wsName]
+	if !ok {
+		t.Fatalf("state not found for workspace %s", wsName)
+	}
+
+	return stateMgr.State()
+}
+
+func ReadWorkspaces(t *testing.T) []string {
+	states.Lock()
+	defer states.Unlock()
+
+	workspaces := make([]string, 0, len(states.m))
+	for wsName := range states.m {
+		workspaces = append(workspaces, wsName)
+	}
+
+	return workspaces
+}

internal/cloud/backend_test.go

@@ -261,7 +261,7 @@ func TestCloud_PrepareConfig(t *testing.T) {
 	}
 
 	for name, tc := range cases {
-		s := testServer(t)
+		s := TestServer(t)
 		b := New(testDisco(s))
 
 		// Validate
@@ -794,7 +794,7 @@ func TestCloud_configVerifyMinimumTFEVersion(t *testing.T) {
 			w.Header().Set("TFP-API-Version", "2.4")
 		},
 	}
-	s := testServerWithHandlers(handlers)
+	s := TestServerWithHandlers(t, handlers)
 
 	b := New(testDisco(s))
 
@@ -831,7 +831,7 @@ func TestCloud_configVerifyMinimumTFEVersionInAutomation(t *testing.T) {
 			w.Header().Set("TFP-API-Version", "2.4")
 		},
 	}
-	s := testServerWithHandlers(handlers)
+	s := TestServerWithHandlers(t, handlers)
 
 	b := New(testDisco(s))
 	b.runningInAutomation = true
@@ -1680,7 +1680,7 @@ func TestCloudBackend_DeleteWorkspace_DoesNotExist(t *testing.T) {
 }
 
 func TestCloud_ServiceDiscoveryAliases(t *testing.T) {
-	s := testServer(t)
+	s := TestServer(t)
 	b := New(testDisco(s))
 
 	diag := b.Configure(cty.ObjectVal(map[string]cty.Value{

internal/cloud/testing.go

@@ -245,9 +245,9 @@ func testBackendWithOutputs(t *testing.T) (*Cloud, func()) {
 func testBackend(t *testing.T, obj cty.Value, handlers map[string]func(http.ResponseWriter, *http.Request)) (*Cloud, *MockClient, func()) {
 	var s *httptest.Server
 	if handlers != nil {
-		s = testServerWithHandlers(handlers)
+		s = TestServerWithHandlers(t, handlers)
 	} else {
-		s = testServer(t)
+		s = TestServer(t)
 	}
 	b := New(testDisco(s))
 
@@ -324,7 +324,7 @@ func testBackend(t *testing.T, obj cty.Value, handlers map[string]func(http.Resp
 // testUnconfiguredBackend is used for testing the configuration of the backend
 // with the mock client
 func testUnconfiguredBackend(t *testing.T) (*Cloud, func()) {
-	s := testServer(t)
+	s := TestServer(t)
 	b := New(testDisco(s))
 
 	// Normally, the client is created during configuration, but the configuration uses the
@@ -395,15 +395,15 @@ func testLocalBackend(t *testing.T, cloud *Cloud) backendrun.OperationsBackend {
 	return b
 }
 
-// testServer returns a started *httptest.Server used for local testing with the default set of
+// TestServer returns a started *httptest.Server used for local testing with the default set of
 // request handlers.
-func testServer(t *testing.T) *httptest.Server {
-	return testServerWithHandlers(testDefaultRequestHandlers)
+func TestServer(t *testing.T) *httptest.Server {
+	return TestServerWithHandlers(t, testDefaultRequestHandlers)
 }
 
-// testServerWithHandlers returns a started *httptest.Server with the given set of request handlers
+// TestServerWithHandlers returns a started *httptest.Server with the given set of request handlers
 // overriding any default request handlers (testDefaultRequestHandlers).
-func testServerWithHandlers(handlers map[string]func(http.ResponseWriter, *http.Request)) *httptest.Server {
+func TestServerWithHandlers(t *testing.T, handlers map[string]func(http.ResponseWriter, *http.Request)) *httptest.Server {
 	mux := http.NewServeMux()
 	for route, handler := range handlers {
 		mux.HandleFunc(route, handler)
@@ -414,6 +414,11 @@ func testServerWithHandlers(handlers map[string]func(http.ResponseWriter, *http.
 		}
 	}
 
+	mux.HandleFunc("/", func(w http.ResponseWriter, req *http.Request) {
+		t.Logf("unexpected %s request received for %q", req.Method, req.URL.String())
+		w.WriteHeader(http.StatusBadRequest)
+	})
+
 	return httptest.NewServer(mux)
 }