Fix top-level name interpolation

newsfragments/top-level-name-attribute-interpolation.bugfix

@@ -0,0 +1 @@
+Fixed top-level `name` attribute interpolation not happening.

podman_compose.py

@@ -2437,6 +2437,7 @@ def _parse_compose_file(self) -> None:
                     project_name = content.get("name")
                 if not project_name:
                     project_name = dir_basename.lower()
+                project_name = rec_subs(project_name, self.environ)
                 # More strict then actually needed for simplicity:
                 # podman requires [a-zA-Z0-9][a-zA-Z0-9_.-]*
                 project_name_normalized = norm_re.sub("", project_name)

tests/integration/env_tests/container-compose.yml

@@ -1,6 +1,6 @@
 version: "3"
 
-name: my-project-name
+name: my-project-name${ZZVAR1:-}
 
 services:
   env-test:

tests/integration/env_tests/test_podman_compose_env.py

@@ -87,3 +87,23 @@ def test_project_name_override(self) -> None:
                 compose_yaml_path(),
                 "down",
             ])
+
+    def test_project_name_interpolation(self) -> None:
+        try:
+            output, _ = self.run_subprocess_assert_returncode([
+                podman_compose_path(),
+                "-f",
+                compose_yaml_path(),
+                "run",
+                "-e",
+                "ZZVAR1=-myval2",
+                "project-name-test",
+            ])
+            self.assertIn("my-project-name-myval2", str(output))
+        finally:
+            self.run_subprocess_assert_returncode([
+                podman_compose_path(),
+                "-f",
+                compose_yaml_path(),
+                "down",
+            ])