interpreter: correctly track whether a subproject is initialized

The way the tracking is currently done it works if no new subprojects
are added to a configured build directory. For cases where we want to
add a new subproject, it fails because we don't initialize builtins for
that subproject. This corrects that by checking to see if the subproject
already exists, and if it doesn't initializes the bultins for it.

Fixes: #8421

1 files changed, 7 insertions, 0 deletions

diff --git a/run_unittests.py b/run_unittests.py
index f7f9fd5..acd775c 100755
--- a/run_unittests.py
+++ b/run_unittests.py
@@ -5544,6 +5544,13 @@ class AllPlatformTests(BasePlatformTests):
         check_installed_files(['--skip-subprojects', 'bar'], main_expected)
         check_installed_files(['--skip-subprojects', 'another'], all_expected)
 
+    def test_adding_subproject_to_configure_project(self) -> None:
+        srcdir = os.path.join(self.unit_test_dir, '92 new subproject in configured project')
+        self.init(srcdir)
+        self.build()
+        self.setconf('-Duse-sub=true')
+        self.build()
+
 
 class FailureTests(BasePlatformTests):
     '''