build the statelocker binary before running

this way we can signal it directly to amke sure it exits cleanly.

command/command_test.go

@@ -536,9 +536,26 @@ func testRemoteState(t *testing.T, s *terraform.State, c int) (*terraform.Remote
 // testlockState calls a separate process to the lock the state file at path.
 // deferFunc should be called in the caller to properly unlock the file.
 func testLockState(path string) (func(), error) {
-	locker := exec.Command("go", "run", "testdata/statelocker.go", path)
+	// build and run the binary ourselves so we can quickly terminate it for cleanup
+	buildDir, err := ioutil.TempDir("", "locker")
+	if err != nil {
+		return nil, err
+	}
+	cleanFunc := func() {
+		os.RemoveAll(buildDir)
+	}
+
+	lockBin := filepath.Join(buildDir, "statelocker")
+	out, err := exec.Command("go", "build", "-o", lockBin, "testdata/statelocker.go").CombinedOutput()
+	if err != nil {
+		cleanFunc()
+		return nil, fmt.Errorf("%s %s", err, out)
+	}
+
+	locker := exec.Command(lockBin, path)
 	pr, pw, err := os.Pipe()
 	if err != nil {
+		cleanFunc()
 		return nil, err
 	}
 	defer pr.Close()
@@ -550,6 +567,7 @@ func testLockState(path string) (func(), error) {
 		return nil, err
 	}
 	deferFunc := func() {
+		cleanFunc()
 		locker.Process.Signal(syscall.SIGTERM)
 		locker.Wait()
 	}
@@ -562,7 +580,7 @@ func testLockState(path string) (func(), error) {
 	}
 
 	if string(buf[:n]) != "LOCKED" {
-		return deferFunc, fmt.Errorf("statelocker wrote", string(buf[:n]))
+		return deferFunc, fmt.Errorf("statelocker wrote: %s", string(buf[:n]))
 	}
 	return deferFunc, nil
 }

command/testdata/statelocker.go

@@ -9,6 +9,7 @@ import (
 	"os"
 	"os/signal"
 	"syscall"
+	"time"
 
 	"github.com/hashicorp/terraform/state"
 )
@@ -38,6 +39,11 @@ func main() {
 	}()
 
 	c := make(chan os.Signal, 1)
-	signal.Notify(c, syscall.SIGINT, syscall.SIGTERM)
-	<-c
+	signal.Notify(c, syscall.SIGINT, syscall.SIGTERM, syscall.SIGHUP)
+
+	// timeout after 10 second in case we don't get cleaned up by the test
+	select {
+	case <-time.After(10 * time.Second):
+	case <-c:
+	}
 }