Add tests for getFileOwner_unix (#48)

datasetIngestor/getFileOwner_unix.go

@@ -10,6 +10,10 @@ import (
 	"syscall"
 )
 
+/* GetFileOwner retrieves the owner of a given file. It takes an os.FileInfo object as input
+and returns two strings: the username of the file's owner and the name of the group that owns the file.
+If the user or group cannot be determined, it returns the user ID or group ID as a string.
+If there is an error during the lookup of the user or group, it prefixes the user ID with "e" and uses the group ID as is.*/
 func GetFileOwner(f os.FileInfo) (uidName string, gidName string) {
 	uid := strconv.Itoa(int(f.Sys().(*syscall.Stat_t).Uid))
 	u, err2 := user.LookupId(uid)

datasetIngestor/getFileOwner_unix_test.go

@@ -0,0 +1,45 @@
+// +build aix darwin dragonfly freebsd js,wasm linux nacl netbsd openbsd solaris
+
+package datasetIngestor
+
+import (
+	"os"
+	"os/user"
+	"testing"
+	"io/ioutil"
+)
+
+func TestGetFileOwner(t *testing.T) {
+	// Create a temporary file
+	tmpfile, err := ioutil.TempFile("", "example")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.Remove(tmpfile.Name()) // clean up
+
+	// Get the current user
+	currentUser, err := user.Current()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Get the file info
+	fileInfo, err := tmpfile.Stat()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Get the file owner
+	uidName, _ := GetFileOwner(fileInfo)
+
+	// Check if the file owner matches the current user
+	if uidName != currentUser.Username {
+		t.Errorf("Expected %s, got %s", currentUser.Username, uidName)
+	}
+
+	// Check owner of a non-existent file
+	_, err = os.Stat("non_existent_file")
+	if err == nil {
+			t.Fatal("Expected error, got none")
+	}
+}