use unload/load in ModuleGeneratorLua.swap_module, since 'swap' is not supported by Lmod

easybuild/tools/module_generator.py

@@ -1430,7 +1430,10 @@ def swap_module(self, mod_name_out, mod_name_in, guarded=True):
         :param mod_name_in: name of module to load (swap in)
         :param guarded: guard 'swap' statement, fall back to 'load' if module being swapped out is not loaded
         """
-        body = 'swap("%s", "%s")' % (mod_name_out, mod_name_in)
+        body = '\n'.join([
+            'unload("%s")' % mod_name_out,
+            'load("%s")' % mod_name_in,
+        ])
         if guarded:
             alt_body = self.LOAD_TEMPLATE % {'mod_name': mod_name_in}
             swap_statement = [self.conditional_statement(self.is_loaded(mod_name_out), body, else_body=alt_body)]

test/framework/module_generator.py

@@ -616,7 +616,8 @@ def test_swap(self):
         else:
             expected = '\n'.join([
                 '',
-                'swap("foo", "bar")',
+                'unload("foo")',
+                'load("bar")',
                 '',
             ])
 
@@ -637,7 +638,8 @@ def test_swap(self):
             expected = '\n'.join([
                 '',
                 'if isloaded("foo") then',
-                '    swap("foo", "bar")',
+                '    unload("foo")',
+                '    load("bar")',
                 'else',
                 '    load("bar")',
                 'end',
@@ -1460,6 +1462,48 @@ def test_det_installdir(self):
 
         self.assertEqual(self.modgen.det_installdir(test_modfile), expected)
 
+    def test_generated_module_file_swap(self):
+        """Test loading a generated module file that includes swap statements."""
+
+        if self.MODULE_GENERATOR_CLASS == ModuleGeneratorLua:
+            mod_ext = '.lua'
+
+            if not isinstance(self.modtool, Lmod):
+                # Lua module files are only supported by Lmod,
+                # so early exit if that's not the case in the test setup
+                return
+
+        else:
+            mod_ext = ''
+
+        # empty test modules
+        for modname in ('one/1.0', 'one/1.1'):
+            modfile = os.path.join(self.test_prefix, modname + mod_ext)
+            write_file(modfile, self.modgen.MODULE_SHEBANG)
+
+        modulepath = os.getenv('MODULEPATH')
+        if modulepath:
+            self.modtool.unuse(modulepath)
+
+        test_mod = os.path.join(self.test_prefix, 'test', '1.0' + mod_ext)
+        test_mod_txt = '\n'.join([
+            self.modgen.MODULE_SHEBANG,
+            self.modgen.swap_module('one', 'one/1.1'),
+        ])
+        write_file(test_mod, test_mod_txt)
+
+        # prepare environment for loading test module
+        self.modtool.use(self.test_prefix)
+        self.modtool.load(['one/1.0'])
+
+        self.modtool.load(['test/1.0'])
+
+        # check whether resulting environment is correct
+        loaded_mods = self.modtool.list()
+        self.assertEqual(loaded_mods[-1]['mod_name'], 'test/1.0')
+        # one/1.0 module was swapped for one/1.1
+        self.assertEqual(loaded_mods[-2]['mod_name'], 'one/1.1')
+
 
 class TclModuleGeneratorTest(ModuleGeneratorTest):
     """Test for module_generator module for Tcl syntax."""