multimethod uses Spec() instead of parse_anonymous_spec()

- simplify logic in multimethod
- remove the requirement of multimethod invocations to walk up the stack.

lib/spack/spack/multimethod.py

@@ -26,11 +26,11 @@
 """
 import functools
 
-from llnl.util.lang import caller_locals, get_calling_module_name
+from llnl.util.lang import caller_locals
 
 import spack.architecture
 import spack.error
-from spack.spec import parse_anonymous_spec
+from spack.spec import Spec
 
 
 class SpecMultiMethod(object):
@@ -46,11 +46,6 @@ class SpecMultiMethod(object):
        to find one that matches the package's spec.  If it finds one
        (and only one), it will call that method.
 
-       The package author is responsible for ensuring that only one
-       condition on multi-methods ever evaluates to true.  If
-       multiple methods evaluate to true, this will raise an
-       exception.
-
        This is intended for use with decorators (see below).  The
        decorator (see docs below) creates SpecMultiMethods and
        registers method versions with them.
@@ -76,7 +71,7 @@ def __init__(self, default=None):
             functools.update_wrapper(self, default)
 
     def register(self, spec, method):
-        """Register a version of a method for a particular sys_type."""
+        """Register a version of a method for a particular spec."""
         self.method_list.append((spec, method))
 
         if not hasattr(self, '__name__'):
@@ -91,6 +86,7 @@ def __get__(self, obj, objtype):
         # element in the list. The first registered function
         # will be the one 'wrapped'.
         wrapped_method = self.method_list[0][1]
+
         # Call functools.wraps manually to get all the attributes
         # we need to be disguised as the wrapped_method
         func = functools.wraps(wrapped_method)(
@@ -178,10 +174,6 @@ def install(self, prefix):
                   self.setup()
                   # Do more common install stuff
 
-       There must be one (and only one) @when clause that matches the
-       package's spec.  If there is more than one, or if none match,
-       then the method will raise an exception when it's called.
-
        Note that the default version of decorated methods must
        *always* come first.  Otherwise it will override all of the
        platform-specific versions.  There's not much we can do to get
@@ -189,11 +181,12 @@ def install(self, prefix):
     """
 
     def __init__(self, spec):
-        pkg = get_calling_module_name()
         if spec is True:
-            spec = pkg
-        self.spec = (parse_anonymous_spec(spec, pkg)
-                     if spec is not False else None)
+            self.spec = Spec()
+        elif spec is not False:
+            self.spec = Spec(spec)
+        else:
+            self.spec = None
 
     def __call__(self, method):
         # Get the first definition of the method in the calling scope

lib/spack/spack/test/spec_semantics.py

@@ -14,7 +14,7 @@
 
 def target_factory(spec_string, target_concrete):
     spec = Spec(spec_string) if spec_string else Spec()
-    print spec, spec_string, "AAAAA"
+
     if target_concrete:
         spec._mark_concrete()
         substitute_abstract_variants(spec)
@@ -27,18 +27,15 @@ def argument_factory(argument_spec, left):
         # If it's not anonymous, allow it
         right = target_factory(argument_spec, False)
     except Exception:
-        print "HAHA"
         right = parse_anonymous_spec(argument_spec, left.name)
     return right
 
 
 def check_satisfies(target_spec, argument_spec, target_concrete=False):
-    
+
     left = target_factory(target_spec, target_concrete)
     right = argument_factory(argument_spec, left)
 
-    print left, 'left', left.name
-    print right, right.name
     # Satisfies is one-directional.
     assert left.satisfies(right)
     if argument_spec:

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

@@ -21,7 +21,7 @@ class Multimethod(MultimethodBase):
     url      = 'http://www.example.com/example-1.0.tar.gz'
 
     #
-    # These functions are only valid for versions 1, 2, and 3.
+    # These functions are only valid for versions 1, 3, and 4.
     #
     @when('@1.0')
     def no_version_2(self):