fix: mutex for tft init

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

@@ -24,6 +24,7 @@ import (
 	"path"
 	"path/filepath"
 	"strings"
+	"sync"
 	gotest "testing"
 	"time"
 
@@ -73,6 +74,7 @@ type TFBlueprintTest struct {
 	verify                        func(*assert.Assertions) // verify function
 	teardown                      func(*assert.Assertions) // teardown function
 	setupOutputOverrides          map[string]interface{}   // override outputs from the Setup phase
+	mutex                         *sync.Mutex              // Mutex to protect Terraform init
 }
 
 type tftOption func(*TFBlueprintTest)
@@ -447,7 +449,10 @@ func (b *TFBlueprintTest) DefaultVerify(assert *assert.Assertions) {
 
 // DefaultInit runs TF init and validate on a blueprint.
 func (b *TFBlueprintTest) DefaultInit(assert *assert.Assertions) {
+	// mutex to prevent parallel calls to Terraform init as plugin cache isn't concurrent safe
+	b.mutex.Lock()
 	terraform.Init(b.t, b.GetTFOptions())
+	b.mutex.Unlock()
 	// if vars are set for common options, this seems to trigger -var flag when calling validate
 	// using custom tfOptions as a workaround
 	terraform.Validate(b.t, terraform.WithDefaultRetryableErrors(b.t, &terraform.Options{