Avoid warning when using other dbdir

R/cpp11.R

@@ -16,6 +16,10 @@ rapi_lock <- function(dual) {
   .Call(`_duckdb_rapi_lock`, dual)
 }
 
+rapi_unlock <- function(dual) {
+  invisible(.Call(`_duckdb_rapi_unlock`, dual))
+}
+
 rapi_is_locked <- function(dual) {
   .Call(`_duckdb_rapi_is_locked`, dual)
 }

R/dbConnect__duckdb_driver.R

@@ -81,6 +81,7 @@ dbConnect__duckdb_driver <- function(
 
   # aha, a late comer. let's make a new instance.
   if (dbdir != drv@dbdir || !rapi_lock(drv@database_ref)) {
+    rapi_unlock(drv@database_ref)
     drv <- duckdb(dbdir, read_only, bigint, config)
   }
 

src/cpp11.cpp

@@ -35,6 +35,14 @@ extern "C" SEXP _duckdb_rapi_lock(SEXP dual) {
   END_CPP11
 }
 // database.cpp
+void rapi_unlock(duckdb::db_eptr_t dual);
+extern "C" SEXP _duckdb_rapi_unlock(SEXP dual) {
+  BEGIN_CPP11
+    rapi_unlock(cpp11::as_cpp<cpp11::decay_t<duckdb::db_eptr_t>>(dual));
+    return R_NilValue;
+  END_CPP11
+}
+// database.cpp
 bool rapi_is_locked(duckdb::db_eptr_t dual);
 extern "C" SEXP _duckdb_rapi_is_locked(SEXP dual) {
   BEGIN_CPP11
@@ -455,6 +463,7 @@ static const R_CallMethodDef CallEntries[] = {
     {"_duckdb_rapi_release",                 (DL_FUNC) &_duckdb_rapi_release,                 1},
     {"_duckdb_rapi_shutdown",                (DL_FUNC) &_duckdb_rapi_shutdown,                1},
     {"_duckdb_rapi_startup",                 (DL_FUNC) &_duckdb_rapi_startup,                 3},
+    {"_duckdb_rapi_unlock",                  (DL_FUNC) &_duckdb_rapi_unlock,                  1},
     {"_duckdb_rapi_unregister_arrow",        (DL_FUNC) &_duckdb_rapi_unregister_arrow,        2},
     {"_duckdb_rapi_unregister_df",           (DL_FUNC) &_duckdb_rapi_unregister_df,           2},
     {NULL, NULL, 0}

src/database.cpp

@@ -84,6 +84,13 @@ static bool CastRstringToVarchar(Vector &source, Vector &result, idx_t count, Ca
 	return dual->has();
 }
 
+[[cpp11::register]] void rapi_unlock(duckdb::db_eptr_t dual) {
+	if (!dual || !dual.get()) {
+		cpp11::stop("rapi_unlock: Invalid database reference");
+	}
+	dual->unlock();
+}
+
 [[cpp11::register]] bool rapi_is_locked(duckdb::db_eptr_t dual) {
 	if (!dual || !dual.get()) {
 		cpp11::stop("rapi_is_locked: Invalid database reference");

tests/testthat/test-connect.R

@@ -47,6 +47,14 @@ test_that("no warning after dbDisconnect() for driver stored in variable", {
   expect_warning(gc(), NA)
 })
 
+test_that("no warning on dbConnect() with other dbdir", {
+  con <- dbConnect(duckdb(), tempfile(fileext = ".duckdb"))
+  dbDisconnect(con)
+
+  # The warning won't occur here anyway, this is to keep testthat happy
+  expect_warning(gc(), NA)
+})
+
 test_that("can connect to the same in-memory database via the same driver object", {
   drv <- duckdb()