separate custom openapi test from the others

Makefile

@@ -229,7 +229,8 @@ generate-kustomize-api: $(MYGOBIN)/k8scopy
 
 .PHONY: test-unit-kustomize-api
 test-unit-kustomize-api: build-kustomize-api
-	cd api; go test ./...  -ldflags "-X sigs.k8s.io/kustomize/api/provenance.version=v444.333.222"
+	cd api; go test ./...  -ldflags "-X sigs.k8s.io/kustomize/api/provenance.version=v444.333.222"; \
+	cd krusty; OPENAPI_TEST=true go test -run TestCustomOpenAPIFieldFromComponentWithOverlays
 
 .PHONY: test-unit-kustomize-plugins
 test-unit-kustomize-plugins:

api/krusty/openapicustomschema_test.go

@@ -5,6 +5,7 @@ package krusty_test
 
 import (
 	"io/ioutil"
+	"os"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -350,6 +351,10 @@ func TestCustomOpenAPIFieldFromComponent(t *testing.T) {
 // test for https://github.com/kubernetes-sigs/kustomize/issues/4179
 // kustomize is not seeing the openapi field from the component defined in the overlay
 func TestCustomOpenAPIFieldFromComponentWithOverlays(t *testing.T) {
+	if val, ok := os.LookupEnv("OPENAPI_TEST"); !ok || val != "true" {
+		t.SkipNow()
+	}
+
 	th := kusttest_test.MakeHarness(t)
 
 	// overlay declaring the component

kyaml/openapi/openapi.go

@@ -547,9 +547,6 @@ func SetSchema(openAPIField map[string]string, schema []byte, reset bool) error
 		return nil
 	}
 
-	// if the schema is changed, initSchema should parse the new schema
-	defer func() { globalSchema.schemaInit = false }()
-
 	version, exists := openAPIField["version"]
 	if exists && schema != nil {
 		return fmt.Errorf("builtin version and custom schema provided, cannot use both")
@@ -558,6 +555,8 @@ func SetSchema(openAPIField map[string]string, schema []byte, reset bool) error
 	if schema != nil { // use custom schema
 		customSchema = schema
 		kubernetesOpenAPIVersion = "custom"
+		// if the schema is changed, initSchema should parse the new schema
+		globalSchema.schemaInit = false
 		return nil
 	}
 
@@ -570,6 +569,8 @@ func SetSchema(openAPIField map[string]string, schema []byte, reset bool) error
 		return fmt.Errorf("the specified OpenAPI version is not built in")
 	}
 	customSchema = nil
+	// if the schema is changed, initSchema should parse the new schema
+	globalSchema.schemaInit = false
 	return nil
 }