fix: Create directories from envs_dirs if they do not exist

libmamba/src/api/configuration.cpp

@@ -490,6 +490,18 @@ namespace mamba
             {
                 for (const auto& dir : dirs)
                 {
+                    if (!fs::exists(dir))
+                    {
+                        try
+                        {
+                            fs::create_directories(dir);
+                        }
+                        catch (const fs::filesystem_error& e)
+                        {
+                            LOG_WARNING << "Error creating directory " << dir << ": " << e.what()
+                                        << std::endl;
+                        }
+                    }
                     const auto candidate = dir / name;
                     if (mamba::path::is_writable(candidate))
                     {

micromamba/tests/test_create.py

@@ -281,8 +281,6 @@ def test_target_prefix(
     else:
         root_prefix = Path(os.environ["MAMBA_ROOT_PREFIX"])
 
-    # TODO: Remove this call to `os.makedirs` once
-    # https://github.com/mamba-org/mamba/issues/3790 is fixed
     if root_prefix_env_exists:
         os.makedirs(Path(os.environ["MAMBA_ROOT_PREFIX"]) / "envs", exist_ok=True)
 
@@ -670,6 +668,25 @@ def test_create_envs_dirs(tmp_root_prefix: Path, tmp_path: Path):
     assert (tmp_path / env_name / "conda-meta" / "history").exists()
 
 
+@pytest.mark.parametrize("envs_dirs_source", ("condarc", "env_var"))
+def test_mkdir_envs_dirs(tmp_path, tmp_home, monkeypatch, envs_dirs_source):
+    """Test that an env dir is created if it does not exist already"""
+
+    envs_dir = tmp_path / "user_provided_envdir" / "envs"
+
+    with open(tmp_home / ".condarc", "w+") as f:
+        if envs_dirs_source == "env_var":
+            monkeypatch.setenv("CONDA_ENVS_DIRS", str(envs_dir))
+        else:
+            f.write(f"envs_dirs: [{str(envs_dir)}]")
+
+    assert not envs_dir.exists()  # directory doesn't exist yet
+
+    helpers.create("-n", "bar", "--rc-file", tmp_home / ".condarc", no_rc=False)
+
+    assert envs_dir.exists()
+
+
 @pytest.mark.parametrize("set_in_conda_envs_dirs", (False, True))
 @pytest.mark.parametrize("set_in_condarc", (False, True))
 @pytest.mark.parametrize("cli_root_prefix", (False, True))
@@ -713,8 +730,6 @@ def test_root_prefix_precedence(
         if set_in_condarc:
             f.write(f"envs_dirs: [{str(condarc_envs_dirs)}]")
 
-    # TODO: Remove this call to `os.makedirs` once
-    # https://github.com/mamba-org/mamba/issues/3790 is fixed
     for envs_folder in (condarc_envs_dirs, conda_envs_dirs, cli_provided_root, mamba_root_prefix):
         os.makedirs(envs_folder, exist_ok=True)