feat: new test strategy for redeploy validation (#1286)

infra/blueprint-test/examples/simple_pet_module/main.tf

@@ -0,0 +1,2 @@
+resource "random_pet" "hello" {
+}

infra/blueprint-test/pkg/tft/terraform.go

@@ -432,3 +432,23 @@ func (b *TFBlueprintTest) Test() {
 	utils.RunStage("apply", func() { b.Apply(a) })
 	utils.RunStage("verify", func() { b.Verify(a) })
 }
+
+// RedeployTest deploys the test n times in separate workspaces before teardown.
+func (b *TFBlueprintTest) RedeployTest(n int) {
+	if b.ShouldSkip() {
+		b.logger.Logf(b.t, "Skipping test due to config %s", b.Path)
+		b.t.SkipNow()
+		return
+	}
+	a := assert.New(b.t)
+	for i := 1; i <= n; i++ {
+		ws := terraform.WorkspaceSelectOrNew(b.t, b.GetTFOptions(), fmt.Sprintf("test-%d", i))
+		utils.RunStage("init", func() { b.Init(a) })
+		defer func() {
+			terraform.WorkspaceSelectOrNew(b.t, b.GetTFOptions(), ws)
+			utils.RunStage("teardown", func() { b.Teardown(a) })
+		}()
+		utils.RunStage("apply", func() { b.Apply(a) })
+		utils.RunStage("verify", func() { b.Verify(a) })
+	}
+}

infra/blueprint-test/test/terraform_redeploy_test.go

@@ -0,0 +1,36 @@
+/**
+ * Copyright 2022 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package test
+
+import (
+	"testing"
+
+	"github.com/GoogleCloudPlatform/cloud-foundation-toolkit/infra/blueprint-test/pkg/tft"
+	"github.com/gruntwork-io/terratest/modules/terraform"
+)
+
+func TestRedeploy(t *testing.T) {
+	nt := tft.NewTFBlueprintTest(t,
+		tft.WithTFDir("../examples/simple_pet_module"),
+		tft.WithSetupPath(""),
+	)
+	nt.RedeployTest(3)
+	expectedWorkspaces := []string{"test-1", "test-2", "test-3"}
+	for _, ws := range expectedWorkspaces {
+		terraform.RunTerraformCommand(t, nt.GetTFOptions(), "workspace", "select", ws)
+	}
+}