Remove shell driven command from env activation test

lib/spack/spack/environment/environment.py

@@ -65,6 +65,11 @@
 #: default path where environments are stored in the spack tree
 default_env_path = os.path.join(spack.paths.var_path, "environments")
 
+# ensure that this base directory exists since we require the root directory to be created
+# in our checks
+if not os.path.isdir(default_env_path):
+    os.mkdir(default_env_path)
+
 
 #: Name of the input yaml file for an environment
 manifest_name = "spack.yaml"
@@ -80,24 +85,21 @@
 
 def env_root_path():
     """Override default root path if the user specified it"""
-    env_path = spack.config.get("config:environments_root", default=default_env_path)
-    canonical_path = spack.util.path.canonicalize_path(env_path, allow_env=False)
-    if env_path == default_env_path:
-        # create the default path if it is missing, if user paths are missing we errors
-        # and force them to create it themselves to keep spack from adding arbitrary directories
-        # and to help debug typos
-        if not os.path.isdir(canonical_path):
-            os.mkdir(canonical_path)
-    return canonical_path
+    return spack.util.path.canonicalize_path(
+        spack.config.get("config:environments_root", default=default_env_path), allow_env=False
+    )
 
 
 def check_disallowed_env_config_mods(scopes):
     for scope in scopes:
         with spack.config.override(scope):
             if spack.config.get("config:environments_root"):
-                raise SpackEnvironmentError("Need a good message")
-            else:
-                spack.config.print_section("config")
+                raise SpackEnvironmentError(
+                    "Spack environments are prohibited from modifying 'config:environments_root' "
+                    "because it can make the definition of the environment ill-posed. Please "
+                    "remove from your environment and place it in a permanent scope such as "
+                    "defaults, system, site, etc."
+                )
     return scopes
 
 

lib/spack/spack/test/config.py

@@ -1463,26 +1463,3 @@ def test_environment_errors_if_root_missing(mutable_config, tmpdir):
 
     with pytest.raises(ev.SpackEnvironmentError, match=env_dir):
         env("create", "test")
-
-
-def test_environment_cant_modify_environments_root(tmpdir):
-    filename = tmpdir.join("spack.yaml")
-    with open(filename, "w") as f:
-        f.write(
-            """\
-spack:
-  config:
-    environments_root: /a/black/hole
-  view: false
-  specs: []
-"""
-        )
-    with tmpdir.as_cwd():
-        with pytest.raises(ev.SpackEnvironmentError):
-            # Why does this raise?
-            e = ev.Environment(tmpdir.strpath)
-            ev.activate(e)
-        with pytest.raises(ev.SpackEnvironmentError):
-            # When this does not?
-            env("create", "-d", tmpdir.strpath)
-            env("activate", "-d", tmpdir.strpath)

lib/spack/spack/test/env.py

@@ -106,6 +106,24 @@ def test_env_change_spec_in_matrix_raises_error(
     assert "Cannot directly change specs in matrices" in str(error)
 
 
+def test_environment_cant_modify_environments_root(tmpdir):
+    filename = tmpdir.join("spack.yaml")
+    with open(filename, "w") as f:
+        f.write(
+            """\
+spack:
+  config:
+    environments_root: /a/black/hole
+  view: false
+  specs: []
+"""
+        )
+    with tmpdir.as_cwd():
+        with pytest.raises(ev.SpackEnvironmentError):
+            e = ev.Environment(tmpdir.strpath)
+            ev.activate(e)
+
+
 def test_activate_should_require_an_env():
     with pytest.raises(TypeError):
         ev.activate(env="name")