go_test: add tests for #2696 (#2698)

tests/legacy/test_chdir/data_test.go

@@ -1,13 +1,31 @@
 package test_chdir
 
 import (
+	"log"
 	"os"
 	"testing"
 )
 
+const file = "data.txt"
+
+func init() {
+	_, err := os.Stat(file)
+	if err != nil {
+		log.Fatalf("in init(), could not stat %s: %v", file, err)
+	}
+}
+
+func TestMain(m *testing.M) {
+	_, err := os.Stat(file)
+	if err != nil {
+		log.Fatalf("in TestMain(), could not stat %s: %v", file, err)
+	}
+	os.Exit(m.Run())
+}
+
 func TestLocal(t *testing.T) {
-	_, err := os.Stat("data.txt")
+	_, err := os.Stat(file)
 	if err != nil {
-		t.Errorf("could not stat local.txt: %v", err)
+		t.Errorf("could not stat %s: %v", file, err)
 	}
 }