move TestReset mock from terraform to helper

the terraform package doesn't know about TestProvider, so don't put the
hooks in terraform.MockResourceProvider. Wrap the mock in the test where
we need to check the TestProvider functionality.

helper/resource/testing_test.go

@@ -6,6 +6,7 @@ import (
 	"os"
 	"regexp"
 	"strings"
+	"sync"
 	"sync/atomic"
 	"testing"
 
@@ -26,8 +27,26 @@ func init() {
 	}
 }
 
+// wrap the mock provider to implement TestProvider
+type resetProvider struct {
+	*terraform.MockResourceProvider
+	mu              sync.Mutex
+	TestResetCalled bool
+	TestResetError  error
+}
+
+func (p *resetProvider) TestReset() error {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	p.TestResetCalled = true
+	return p.TestResetError
+}
+
 func TestTest(t *testing.T) {
-	mp := testProvider()
+	mp := &resetProvider{
+		MockResourceProvider: testProvider(),
+	}
+
 	mp.DiffReturn = nil
 
 	mp.ApplyFn = func(
@@ -384,8 +403,10 @@ func TestTest_factoryError(t *testing.T) {
 }
 
 func TestTest_resetError(t *testing.T) {
-	mp := testProvider()
+	mp := &resetProvider{
-	mp.TestResetError = fmt.Errorf("provider reset error")
+		MockResourceProvider: testProvider(),
+		TestResetError:       fmt.Errorf("provider reset error"),
+	}
 
 	mt := new(mockT)
 	Test(mt, TestCase{

terraform/resource_provider_mock.go

@@ -56,8 +56,6 @@ type MockResourceProvider struct {
 	ReadDataDiffFn                 func(*InstanceInfo, *ResourceConfig) (*InstanceDiff, error)
 	ReadDataDiffReturn             *InstanceDiff
 	ReadDataDiffReturnError        error
-	TestResetCalled                bool
-	TestResetError                 error
 	StopCalled                     bool
 	StopFn                         func() error
 	StopReturnError                error
@@ -146,14 +144,6 @@ func (p *MockResourceProvider) Configure(c *ResourceConfig) error {
 	return p.ConfigureReturnError
 }
 
-func (p *MockResourceProvider) TestReset() error {
-	p.Lock()
-	defer p.Unlock()
-
-	p.TestResetCalled = true
-	return p.TestResetError
-}
-
 func (p *MockResourceProvider) Stop() error {
 	p.Lock()
 	defer p.Unlock()