diff --git a/lib/spack/docs/developer_guide.rst b/lib/spack/docs/developer_guide.rst
index eca5accb15c7cb230b1fadd97a6e5cbdec67ac7b..47b98a211db06e024d9a145f7b4188b11ea1b6b8 100644
--- a/lib/spack/docs/developer_guide.rst
+++ b/lib/spack/docs/developer_guide.rst
@@ -3,6 +3,8 @@
Developer Guide
=====================
+This guide is intended for people who want to work on Spack's inner
+workings. Right now it's pretty sparse.
Spec objects
-------------------------
diff --git a/lib/spack/docs/packaging_guide.rst b/lib/spack/docs/packaging_guide.rst
index 55f7391cd9817c74f7334d6b08ff999fc4e728c9..75e738efcda4614d4ba6db636a3398aa37485cfe 100644
--- a/lib/spack/docs/packaging_guide.rst
+++ b/lib/spack/docs/packaging_guide.rst
@@ -1060,17 +1060,17 @@ for example:
# the default, called when no @when specs match
pass
- @when('mpi@3:')
+ @when('^mpi@3:')
def setup_mpi(self):
# this will be called when mpi is version 3 or higher
pass
- @when('mpi@2:')
+ @when('^mpi@2:')
def setup_mpi(self):
# this will be called when mpi is version 2 or higher
pass
- @when('mpi@1:')
+ @when('^mpi@1:')
def setup_mpi(self):
# this will be called when mpi is version 1 or higher
pass
diff --git a/lib/spack/spack/multimethod.py b/lib/spack/spack/multimethod.py
index f4de6445daad3d032857815a628530edb2124953..46ddb90d329adaf7a0012d93dacf3c55e4544a94 100644
--- a/lib/spack/spack/multimethod.py
+++ b/lib/spack/spack/multimethod.py
@@ -52,20 +52,20 @@ class SpecMultiMethod(object):
registers method versions with them.
To register a method, you can do something like this:
- mf = SpecMultiMethod()
- mf.register("^chaos_5_x86_64_ib", some_method)
+ mm = SpecMultiMethod()
+ mm.register("^chaos_5_x86_64_ib", some_method)
The object registered needs to be a Spec or some string that
will parse to be a valid spec.
- When the pmf is actually called, it selects a version of the
+ When the mm is actually called, it selects a version of the
method to call based on the sys_type of the object it is
called on.
See the docs for decorators below for more details.
"""
def __init__(self, default=None):
- self.method_map = {}
+ self.method_list = []
self.default = default
if default:
functools.update_wrapper(self, default)
@@ -73,7 +73,7 @@ def __init__(self, default=None):
def register(self, spec, method):
"""Register a version of a method for a particular sys_type."""
- self.method_map[spec] = method
+ self.method_list.append((spec, method))
if not hasattr(self, '__name__'):
functools.update_wrapper(self, method)
@@ -87,33 +87,25 @@ def __get__(self, obj, objtype):
def __call__(self, package_self, *args, **kwargs):
- """Try to find a method that matches package_self.sys_type.
- If none is found, call the default method that this was
- initialized with. If there is no default, raise an error.
+ """Find the first method with a spec that matches the
+ package's spec. If none is found, call the default
+ or if there is none, then raise a NoSuchMethodError.
"""
- spec = package_self.spec
- matching_specs = [s for s in self.method_map if s.satisfies(spec)]
- num_matches = len(matching_specs)
- if num_matches == 0:
- if self.default is None:
- raise NoSuchMethodError(type(package_self), self.__name__,
- spec, self.method_map.keys())
- else:
- method = self.default
-
- elif num_matches == 1:
- method = self.method_map[matching_specs[0]]
+ for spec, method in self.method_list:
+ if spec.satisfies(package_self.spec):
+ return method(package_self, *args, **kwargs)
+ if self.default:
+ return self.default(package_self, *args, **kwargs)
else:
- raise AmbiguousMethodError(type(package_self), self.__name__,
- spec, matching_specs)
-
- return method(package_self, *args, **kwargs)
+ raise NoSuchMethodError(
+ type(package_self), self.__name__, spec,
+ [m[0] for m in self.method_list])
def __str__(self):
return "SpecMultiMethod {\n\tdefault: %s,\n\tspecs: %s\n}" % (
- self.default, self.method_map)
+ self.default, self.method_list)
class when(object):
@@ -207,12 +199,3 @@ def __init__(self, cls, method_name, spec, possible_specs):
"Package %s does not support %s called with %s. Options are: %s"
% (cls.__name__, method_name, spec,
", ".join(str(s) for s in possible_specs)))
-
-
-class AmbiguousMethodError(spack.error.SpackError):
- """Raised when we can't find a version of a multi-method."""
- def __init__(self, cls, method_name, spec, matching_specs):
- super(AmbiguousMethodError, self).__init__(
- "Package %s has multiple versions of %s that match %s: %s"
- % (cls.__name__, method_name, spec,
- ",".join(str(s) for s in matching_specs)))
diff --git a/lib/spack/spack/test/mock_packages/multimethod.py b/lib/spack/spack/test/mock_packages/multimethod.py
index e5c2f5243e6a698ae81ca34857d7ca3852331968..6b6aca976732ae8e8f1d8d1852b807029b495667 100644
--- a/lib/spack/spack/test/mock_packages/multimethod.py
+++ b/lib/spack/spack/test/mock_packages/multimethod.py
@@ -27,16 +27,35 @@ def no_version_2(self):
#
- # These functions overlap too much, so there is ambiguity
+ # These functions overlap, so there is ambiguity, but we'll take
+ # the first one.
#
@when('@:4')
def version_overlap(self):
- pass
+ return 1
@when('@2:')
def version_overlap(self):
- pass
+ return 2
+
+
+ #
+ # More complicated case with cascading versions.
+ #
+ def mpi_version(self):
+ return 0
+ @when('^mpi@3:')
+ def mpi_version(self):
+ return 3
+
+ @when('^mpi@2:')
+ def mpi_version(self):
+ return 2
+
+ @when('^mpi@1:')
+ def mpi_version(self):
+ return 1
#
diff --git a/lib/spack/spack/test/multimethod.py b/lib/spack/spack/test/multimethod.py
index 969c987da854b4c97bf1ae5aff62295f8a6a8f37..3a164a3d20660fd03e7e8f34bc919dcd71a37d5d 100644
--- a/lib/spack/spack/test/multimethod.py
+++ b/lib/spack/spack/test/multimethod.py
@@ -30,8 +30,30 @@ def test_one_version_match(self):
def test_version_overlap(self):
- pkg = packages.get('multimethod@3.0')
- self.assertRaises(AmbiguousMethodError, pkg.version_overlap)
+ pkg = packages.get('multimethod@2.0')
+ self.assertEqual(pkg.version_overlap(), 1)
+
+ pkg = packages.get('multimethod@5.0')
+ self.assertEqual(pkg.version_overlap(), 2)
+
+
+ def test_mpi_version(self):
+ pkg = packages.get('multimethod^mpich@3.0.4')
+ self.assertEqual(pkg.mpi_version(), 3)
+
+ pkg = packages.get('multimethod^mpich2@1.2')
+ self.assertEqual(pkg.mpi_version(), 2)
+
+ pkg = packages.get('multimethod^mpich@1.0')
+ self.assertEqual(pkg.mpi_version(), 1)
+
+
+ def test_undefined_mpi_version(self):
+ # This currently fails because provides() doesn't do
+ # the right thing undefined version ranges.
+ # TODO: fix this.
+ pkg = packages.get('multimethod^mpich@0.4')
+ self.assertEqual(pkg.mpi_version(), 0)
def test_default_works(self):
@@ -69,11 +91,10 @@ def test_dependency_match(self):
pkg = packages.get('multimethod^mpich')
self.assertEqual(pkg.different_by_dep(), 'mpich')
-
- def test_ambiguous_dep(self):
- """If we try to switch on some entirely different dep, it's ambiguous"""
+ # If we try to switch on some entirely different dep, it's ambiguous,
+ # but should take the first option
pkg = packages.get('multimethod^foobar')
- self.assertRaises(AmbiguousMethodError, pkg.different_by_dep)
+ self.assertEqual(pkg.different_by_dep(), 'mpich')
def test_virtual_dep_match(self):