Add a comment and case for down case

tests/e2e/allow_missing_test.go

@@ -315,7 +315,7 @@ func TestMigrateAllowMissingDown(t *testing.T) {
 	}
 }
 
-func TestUpWithAndWithoutAllowMissing(t *testing.T) {
+func TestWithWithoutAllowMissing(t *testing.T) {
 	// Test for https://github.com/pressly/goose/issues/521
 
 	// Apply 1,2,4,3 then run up without allow missing. If the next requested migration is
@@ -335,6 +335,20 @@ func TestUpWithAndWithoutAllowMissing(t *testing.T) {
 	check.NoError(t, err)
 	err = goose.UpTo(db, migrationsDir, 4, goose.WithAllowMissing())
 	check.NoError(t, err)
+
+	// Rollback migration 3 because it is the last applied migration.
+	// But, we want to change this behaviour to apply rollback migration 4.
+	// See these issues for more details:
+	// https://github.com/pressly/goose/issues/523
+	// https://github.com/pressly/goose/issues/402
+	//
+	// Adding this test to ensure the behaviour is updated and captured in a test.
+	err = goose.Down(db, migrationsDir)
+	check.NoError(t, err)
+
+	version, err := goose.GetDBVersion(db)
+	check.NoError(t, err)
+	check.Number(t, version, 4)
 }
 
 // setupTestDB is helper to setup a DB and apply migrations