multimethod: slight refactoring, documentation for code review

var/spack/repos/builtin.mock/packages/multimethod-diamond-parent/package.py

@@ -18,4 +18,4 @@ def diamond_inheritance(self):
 
     @when('@4.0, 2.0')
     def diamond_inheritance(self):
-        return "should never be reached"
+        return "should never be reached by diamond inheritance test"

var/spack/repos/builtin.mock/packages/multimethod/package.py

@@ -148,4 +148,23 @@ def diamond_inheritance(self):
 
     @when('@4.0')
     def diamond_inheritance(self):
-        return "should_not_be_reached"
+        return "should_not_be_reached by diamond inheritance test"
+
+    #
+    # Check that multimethods work with boolean values
+    #
+    @when(True)
+    def boolean_true_first(self):
+        return 'True'
+
+    @when(False)
+    def boolean_true_first(self):
+        return 'False'
+
+    @when(False)
+    def boolean_false_first(self):
+        return 'False'
+
+    @when(True)
+    def boolean_false_first(self):
+        return 'True'