[cifuzz][helper] Fix error message for nonexistent external project (#6558)

Say path doesn't exist instead of the last directory in path.

Fixes: https://github.com/google/oss-fuzz/issues/6528

1 files changed, 9 insertions, 4 deletions

diff --git a/infra/helper.py b/infra/helper.py
index db9f76b6a..805f39a99 100755
--- a/infra/helper.py
+++ b/infra/helper.py
@@ -372,11 +372,16 @@ def is_base_image(image_name):
 
 def check_project_exists(project):
   """Checks if a project exists."""
-  if not os.path.exists(project.path):
-    logging.error('%s does not exist.', project.name)
-    return False
+  if os.path.exists(project.path):
+    return True
 
-  return True
+  if project.is_external:
+    descriptive_project_name = project.path
+  else:
+    descriptive_project_name = project.name
+
+  logging.error('"%s" does not exist.', descriptive_project_name)
+  return False
 
 
 def _check_fuzzer_exists(project, fuzzer_name):