lib/spack : expand spack config vars in 'include' section (#16210)

* Changed the 'include' config section to use 'substitute_path_variables' to allow for Spack config variables to be used (e.g. $spack).

* Fixed a bug with 'include' section path expansion and added a test case for 'include' paths with embedded config variables.

lib/spack/spack/environment.py

@@ -37,6 +37,7 @@
 from spack.spec_list import SpecList, InvalidSpecConstraintError
 from spack.variant import UnknownVariantError
 import spack.util.lock as lk
+from spack.util.path import substitute_path_variables
 
 #: environment variable used to indicate the active environment
 spack_env_var = 'SPACK_ENV'
@@ -780,8 +781,8 @@ def included_config_scopes(self):
         # highest-precedence scopes are last.
         includes = config_dict(self.yaml).get('include', [])
         for i, config_path in enumerate(reversed(includes)):
-            # allow paths to contain environment variables
+            # allow paths to contain spack config/environment variables, etc.
-            config_path = config_path.format(**os.environ)
+            config_path = substitute_path_variables(config_path)
 
             # treat relative paths as relative to the environment
             if not os.path.isabs(config_path):

lib/spack/spack/test/cmd/env.py

@@ -22,6 +22,7 @@
 from spack.spec_list import SpecListError
 from spack.util.mock_package import MockPackageMultiRepo
 import spack.util.spack_json as sjson
+from spack.util.path import substitute_path_variables
 
 
 # everything here uses the mock_env_path
@@ -539,6 +540,35 @@ def test_env_with_included_config_scope():
                for x in e._get_environment_specs())
 
 
+def test_env_with_included_config_var_path():
+    config_var_path = os.path.join('$tempdir', 'included-config.yaml')
+    test_config = """\
+env:
+  include:
+  - %s
+  specs:
+  - mpileaks
+""" % config_var_path
+
+    _env_create('test', StringIO(test_config))
+    e = ev.read('test')
+
+    config_real_path = substitute_path_variables(config_var_path)
+    fs.mkdirp(os.path.dirname(config_real_path))
+    with open(config_real_path, 'w') as f:
+        f.write("""\
+packages:
+  mpileaks:
+    version: [2.2]
+""")
+
+    with e:
+        e.concretize()
+
+    assert any(x.satisfies('mpileaks@2.2')
+               for x in e._get_environment_specs())
+
+
 def test_env_config_precedence():
     test_config = """\
 env: