[feat] Add command-line option to manipulate the module path before executing any tests

docs/manpage.rst

@@ -387,6 +387,16 @@ It does so by leveraging the selected system's environment modules system.
    This option can also be set using the :envvar:`RFM_UNLOAD_MODULES` environment variable or the :js:attr:`unload_modules` general configuration parameter.
 
 
+.. option:: --module-path=PATH
+
+   Manipulate the ``MODULEPATH`` environment variable before acting on any tests.
+   If ``PATH`` starts with the `-` character, it will be removed from the ``MODULEPATH``, whereas if it starts with the `+` character, it will be added to it.
+   In all other cases, ``PATH`` will completely override MODULEPATH.
+   This option may be specified multiple times, in which case all the paths specified will be added or removed in order.
+
+   .. versionadded:: 3.3
+
+
 .. option:: --purge-env
 
    Unload all environment modules before acting on any tests.
@@ -883,6 +893,21 @@ Here is an alphabetical list of the environment variables recognized by ReFrame:
       ================================== ==================
 
 
+.. versionadded:: 3.3
+
+.. envvar:: RFM_UNUSE_MODULE_PATHS
+
+   A colon-separated list of module paths to be unused before acting on any tests.
+
+   .. table::
+      :align: left
+
+      ================================== ==================
+      Associated command line option     :option:`--unuse-module-path`
+      Associated configuration parameter :js:attr:`unuse_module_paths` general configuration parameter
+      ================================== ==================
+
+
 .. envvar:: RFM_USE_LOGIN_SHELL
 
    Use a login shell for the generated job scripts.

reframe/core/modules.py

@@ -400,8 +400,22 @@ class ModulesSystemImpl(abc.ABC):
     :meta private:
     '''
 
-    @abc.abstractmethod
     def execute(self, cmd, *args):
+        '''Execute an arbitrary module command using the modules backend.
+
+        :arg cmd: The command to execute, e.g., ``load``, ``restore`` etc.
+        :arg args: The arguments to pass to the command.
+        :returns: The command output.
+        '''
+        try:
+            exec_output = self._execute(cmd, *args)
+        except SpawnedProcessError as e:
+            raise EnvironError('could not execute module operation') from e
+
+        return exec_output
+
+    @abc.abstractmethod
+    def _execute(self, cmd, *args):
         '''Execute an arbitrary command of the module system.'''
 
     @abc.abstractmethod
@@ -539,7 +553,7 @@ def version(self):
     def modulecmd(self, *args):
         return ' '.join(['modulecmd', 'python', *args])
 
-    def execute(self, cmd, *args):
+    def _execute(self, cmd, *args):
         modulecmd = self.modulecmd(cmd, *args)
         completed = osext.run_command(modulecmd)
         if re.search(r'ERROR', completed.stderr) is not None:
@@ -661,7 +675,7 @@ def name(self):
     def modulecmd(self, *args):
         return ' '.join([self._command, *args])
 
-    def execute(self, cmd, *args):
+    def _execute(self, cmd, *args):
         modulecmd = self.modulecmd(cmd, *args)
         completed = osext.run_command(modulecmd)
         if re.search(r'ERROR', completed.stderr) is not None:
@@ -722,7 +736,7 @@ def name(self):
     def modulecmd(self, *args):
         return ' '.join(['modulecmd', 'python', *args])
 
-    def execute(self, cmd, *args):
+    def _execute(self, cmd, *args):
         modulecmd = self.modulecmd(cmd, *args)
         completed = osext.run_command(modulecmd, check=False)
         namespace = {}
@@ -883,7 +897,7 @@ def loaded_modules(self):
     def conflicted_modules(self, module):
         return []
 
-    def execute(self, cmd, *args):
+    def _execute(self, cmd, *args):
         return ''
 
     def load_module(self, module):

reframe/frontend/cli.py

@@ -359,6 +359,11 @@ def main():
         help='Unload module MOD before running any regression check',
         envvar='RFM_UNLOAD_MODULES ,', configvar='general/unload_modules'
     )
+    env_options.add_argument(
+        '--module-path', action='append', metavar='PATH',
+        dest='module_paths', default=[],
+        help='(Un)use module path PATH before running any regression check',
+    )
     env_options.add_argument(
         '--purge-env', action='store_true', dest='purge_env', default=False,
         help='Unload all modules before running any regression check',
@@ -733,6 +738,35 @@ def print_infoline(param, value):
             printer.debug(str(e))
             raise
 
+        printer.debug('(Un)using module paths from command line')
+        for d in options.module_paths:
+            if d.startswith('-'):
+                try:
+                    rt.modules_system.searchpath_remove(d[1:])
+                except errors.EnvironError as e:
+                    printer.warning(
+                        f'could not remove module path {d} correctly; '
+                        f'skipping...'
+                    )
+                    printer.verbose(str(e))
+            elif d.startswith('+'):
+                try:
+                    rt.modules_system.searchpath_add(d[1:])
+                except errors.EnvironError as e:
+                    printer.warning(
+                        f'could not add module path {d} correctly; '
+                        f'skipping...'
+                    )
+                    printer.verbose(str(e))
+            else:
+                # Here we make sure that we don't try to remove an empty path
+                # from the searchpath
+                searchpath = [p for p in rt.modules_system.searchpath if p]
+                if searchpath:
+                    rt.modules_system.searchpath_remove(*searchpath)
+
+                rt.modules_system.searchpath_add(d)
+
         printer.debug('Loading user modules from command line')
         for m in site_config.get('general/0/user_modules'):
             try:

unittests/test_cli.py

@@ -591,6 +591,59 @@ def test_unload_module(run_reframe, user_exec_ctx):
     assert returncode == 0
 
 
+def test_unuse_module_path(run_reframe, user_exec_ctx, monkeypatch):
+    ms = rt.runtime().modules_system
+    if ms.name == 'nomod':
+        pytest.skip('no modules system found')
+
+    module_path = 'unittests/modules'
+    monkeypatch.setenv('MODULEPATH', module_path)
+    returncode, stdout, stderr = run_reframe(
+        more_options=[f'--module-path=-{module_path}', '--module=testmod_foo'],
+        config_file=fixtures.USER_CONFIG_FILE, action='run',
+        system=rt.runtime().system.name
+    )
+    assert "could not load module 'testmod_foo' correctly" in stdout
+    assert 'Traceback' not in stderr
+    assert returncode == 0
+
+
+def test_use_module_path(run_reframe, user_exec_ctx):
+    ms = rt.runtime().modules_system
+    if ms.name == 'nomod':
+        pytest.skip('no modules system found')
+
+    module_path = 'unittests/modules'
+    returncode, stdout, stderr = run_reframe(
+        more_options=[f'--module-path=+{module_path}', '--module=testmod_foo'],
+        config_file=fixtures.USER_CONFIG_FILE, action='run',
+        system=rt.runtime().system.name
+    )
+
+    assert 'Traceback' not in stdout
+    assert 'Traceback' not in stderr
+    assert "could not load module 'testmod_foo' correctly" not in stdout
+    assert returncode == 0
+
+
+def test_overwrite_module_path(run_reframe, user_exec_ctx):
+    ms = rt.runtime().modules_system
+    if ms.name == 'nomod':
+        pytest.skip('no modules system found')
+
+    module_path = 'unittests/modules'
+    returncode, stdout, stderr = run_reframe(
+        more_options=[f'--module-path={module_path}', '--module=testmod_foo'],
+        config_file=fixtures.USER_CONFIG_FILE, action='run',
+        system=rt.runtime().system.name
+    )
+
+    assert 'Traceback' not in stdout
+    assert 'Traceback' not in stderr
+    assert "could not load module 'testmod_foo' correctly" not in stdout
+    assert returncode == 0
+
+
 def test_failure_stats(run_reframe):
     returncode, stdout, stderr = run_reframe(
         checkpath=['unittests/resources/checks/frontend_checks.py'],

unittests/test_environments.py

@@ -10,7 +10,7 @@
 import reframe.core.environments as env
 import reframe.core.runtime as rt
 import unittests.fixtures as fixtures
-from reframe.core.exceptions import (EnvironError, SpawnedProcessError)
+from reframe.core.exceptions import EnvironError
 
 
 @pytest.fixture
@@ -275,7 +275,7 @@ def test_emit_loadenv_failure(user_runtime):
 
     # Suppress the module load error and verify that the original environment
     # is preserved
-    with contextlib.suppress(SpawnedProcessError):
+    with contextlib.suppress(EnvironError):
         rt.emit_loadenv_commands(environ)
 
     assert rt.snapshot() == snap

unittests/test_modules.py

@@ -12,9 +12,7 @@
 import reframe.utility as util
 import reframe.utility.osext as osext
 import unittests.fixtures as fixtures
-from reframe.core.exceptions import (ConfigError,
-                                     EnvironError,
-                                     SpawnedProcessError)
+from reframe.core.exceptions import (ConfigError, EnvironError)
 from reframe.core.runtime import runtime
 
 
@@ -80,7 +78,7 @@ def test_module_load(modules_system):
         modules_system.load_module('foo')
         modules_system.unload_module('foo')
     else:
-        with pytest.raises(SpawnedProcessError):
+        with pytest.raises(EnvironError):
             modules_system.load_module('foo')
 
         assert not modules_system.is_module_loaded('foo')
@@ -307,7 +305,7 @@ def loaded_modules(self):
         def conflicted_modules(self, module):
             return []
 
-        def execute(self, cmd, *args):
+        def _execute(self, cmd, *args):
             return ''
 
         def load_module(self, module):