Modules suffixes config are now spec format strings (#38411)

lib/spack/docs/module_file_support.rst

@@ -457,11 +457,11 @@ For instance, the following config options,
        tcl:
          all:
            suffixes:
-             ^python@3.12: 'python-3.12'
+             ^python@3: 'python{^python.version}'
              ^openblas: 'openblas'
 
-will add a ``python-3.12`` version string to any packages compiled with
-Python matching the spec, ``python@3.12``. This is useful to know which
+will add a ``python-3.12.1`` version string to any packages compiled with
+Python matching the spec, ``python@3``. This is useful to know which
 version of Python a set of Python extensions is associated with. Likewise, the
 ``openblas`` string is attached to any program that has openblas in the spec,
 most likely via the ``+blas`` variant specification.

lib/spack/spack/modules/common.py

@@ -527,7 +527,8 @@ def use_name(self):
         parts = name.split("/")
         name = os.path.join(*parts)
         # Add optional suffixes based on constraints
-        path_elements = [name] + self.conf.suffixes
+        path_elements = [name]
+        path_elements.extend(map(self.spec.format, self.conf.suffixes))
         return "-".join(path_elements)
 
     @property

lib/spack/spack/test/data/modules/tcl/suffix-format.yaml

@@ -0,0 +1,9 @@
+enable:
+  - tcl
+tcl:
+  all:
+    autoload: none
+  mpileaks:
+    suffixes:
+      mpileaks: 'debug={variants.debug.value}'
+      '^mpi': 'mpi={^mpi.name}-v{^mpi.version}'

lib/spack/spack/test/modules/tcl.py

@@ -377,6 +377,14 @@ def test_suffixes(self, module_configuration, factory):
         writer, spec = factory("mpileaks~debug+opt target=x86_64")
         assert "baz-foo-bar" in writer.layout.use_name
 
+    def test_suffixes_format(self, module_configuration, factory):
+        """Tests adding suffixes as spec format string to module file name."""
+        module_configuration("suffix-format")
+
+        writer, spec = factory("mpileaks +debug target=x86_64 ^mpich@3.0.4")
+        assert "debug=True" in writer.layout.use_name
+        assert "mpi=mpich-v3.0.4" in writer.layout.use_name
+
     def test_setup_environment(self, modulefile_content, module_configuration):
         """Tests the internal set-up of run-time environment."""