add backend refresh test with provider config

backend/local/backend_refresh_test.go

@@ -142,6 +142,56 @@ test_instance.foo:
 	`)
 }
 
+func TestLocal_refreshValidateProviderConfigured(t *testing.T) {
+	b, cleanup := TestLocal(t)
+	defer cleanup()
+
+	schema := &terraform.ProviderSchema{
+		Provider: &configschema.Block{
+			Attributes: map[string]*configschema.Attribute{
+				"value": {Type: cty.String, Optional: true},
+			},
+		},
+		ResourceTypes: map[string]*configschema.Block{
+			"test_instance": {
+				Attributes: map[string]*configschema.Attribute{
+					"id":  {Type: cty.String, Computed: true},
+					"ami": {Type: cty.String, Optional: true},
+				},
+			},
+		},
+	}
+
+	p := TestLocalProvider(t, b, "test", schema)
+	testStateFile(t, b.StatePath, testRefreshState())
+	p.ReadResourceFn = nil
+	p.ReadResourceResponse = providers.ReadResourceResponse{NewState: cty.ObjectVal(map[string]cty.Value{
+		"id": cty.StringVal("yes"),
+	})}
+
+	// Enable validation
+	b.OpValidation = true
+
+	op, configCleanup := testOperationRefresh(t, "./testdata/refresh-provider-config")
+	defer configCleanup()
+
+	run, err := b.Operation(context.Background(), op)
+	if err != nil {
+		t.Fatalf("bad: %s", err)
+	}
+	<-run.Done()
+
+	if !p.PrepareProviderConfigCalled {
+		t.Fatal("Prepare provider config should be called")
+	}
+
+	checkState(t, b.StateOutPath, `
+test_instance.foo:
+  ID = yes
+  provider = provider["registry.terraform.io/hashicorp/test"]
+	`)
+}
+
 // This test validates the state lacking behavior when the inner call to
 // Context() fails
 func TestLocal_refresh_context_error(t *testing.T) {

backend/local/testdata/refresh-provider-config/main.tf

@@ -0,0 +1,7 @@
+resource "test_instance" "foo" {
+    ami = "bar"
+}
+
+provider "test" {
+    value = "foo"
+}