Fixed file modified time not changing on Windows

Signed-off-by: Darren Stahl <darst@microsoft.com>

system/lstat_unix_test.go

@@ -0,0 +1,30 @@
+// +build linux freebsd
+
+package system
+
+import (
+	"os"
+	"testing"
+)
+
+// TestLstat tests Lstat for existing and non existing files
+func TestLstat(t *testing.T) {
+	file, invalid, _, dir := prepareFiles(t)
+	defer os.RemoveAll(dir)
+
+	statFile, err := Lstat(file)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if statFile == nil {
+		t.Fatal("returned empty stat for existing file")
+	}
+
+	statInvalid, err := Lstat(invalid)
+	if err == nil {
+		t.Fatal("did not return error for non-existing file")
+	}
+	if statInvalid != nil {
+		t.Fatal("returned non-nil stat for non-existing file")
+	}
+}