Set Geant4 cmake module path environment variable in dependents. (#11112)

var/spack/repos/builtin/packages/geant4/package.py

@@ -143,3 +143,16 @@ def make_data_links(self):
             for d in dirs:
                 target = os.readlink(d)
                 os.symlink(target, os.path.basename(target))
+
+    def setup_dependent_environment(self, spack_env, run_env, dep_spec):
+        version = self.version
+        major = version[0]
+        minor = version[1]
+        if len(version) > 2:
+            patch = version[-1]
+        else:
+            patch = 0
+        datadir = 'Geant4-%s.%s.%s' % (major, minor, patch)
+        spack_env.append_path('CMAKE_MODULE_PATH',
+                              '{0}/{1}/Modules'.format(
+                                  self.prefix.lib64, datadir))