syscallcompat: move test setup into its own file

The infrastructure will also be used by the upcoming
OpenNofollow tests.

internal/syscallcompat/emulate_test.go

@@ -1,8 +1,6 @@
 package syscallcompat
 
 import (
-	"fmt"
-	"io/ioutil"
 	"os"
 	"syscall"
 	"testing"
@@ -10,45 +8,6 @@ import (
 	"golang.org/x/sys/unix"
 )
 
-var tmpDir string
-var tmpDirFd int
-
-func TestMain(m *testing.M) {
-	origWd, err := os.Getwd()
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	parent := "/tmp/gocryptfs-test-parent"
-	err = os.MkdirAll(parent, 0700)
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	tmpDir, err = ioutil.TempDir(parent, "syscallcompat")
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	dirf, err := os.Open(tmpDir)
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	defer dirf.Close()
-	tmpDirFd = int(dirf.Fd())
-	// Run the tests
-	r := m.Run()
-	// Check that we are in the same directory again (the emulated syscalls
-	// use Fchdir a lot)
-	cwd, _ := os.Getwd()
-	if cwd != origWd {
-		fmt.Printf("working dir has changed from %q to %q", origWd, cwd)
-		os.Exit(1)
-	}
-	os.Exit(r)
-}
-
 func TestEmulateOpenat(t *testing.T) {
 	_, err := emulateOpenat(tmpDirFd, "testOpenAt", 0, 0)
 	if err == nil {

internal/syscallcompat/main_test.go

@@ -0,0 +1,47 @@
+package syscallcompat
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"testing"
+)
+
+var tmpDir string
+var tmpDirFd int
+
+func TestMain(m *testing.M) {
+	origWd, err := os.Getwd()
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	parent := "/tmp/gocryptfs-test-parent"
+	err = os.MkdirAll(parent, 0700)
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	tmpDir, err = ioutil.TempDir(parent, "syscallcompat")
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	dirf, err := os.Open(tmpDir)
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	defer dirf.Close()
+	tmpDirFd = int(dirf.Fd())
+	// Run the tests
+	r := m.Run()
+	// Check that we are in the same directory again (the emulated syscalls
+	// use Fchdir a lot)
+	cwd, _ := os.Getwd()
+	if cwd != origWd {
+		fmt.Printf("working dir has changed from %q to %q", origWd, cwd)
+		os.Exit(1)
+	}
+	os.Exit(r)
+}