spack dependencies: support --deptype argument

- `spack dependencies` can now take a --deptype argument to only traverse
  particular deptypes

- add a new "common" argument for deptype in spack.cmd.common.arguments

- Database.installed_relatives() can now also take a deptype argument
  - this is used by `spack dependencies --installed`

lib/spack/spack/cmd/common/arguments.py

@@ -9,6 +9,7 @@
 
 import spack.cmd
 import spack.config
+import spack.dependency as dep
 import spack.environment as ev
 import spack.modules
 import spack.spec
@@ -104,6 +105,19 @@ def default(self, value):
         pass
 
 
+class DeptypeAction(argparse.Action):
+    """Creates a tuple of valid dependency tpyes from a deptype argument."""
+    def __call__(self, parser, namespace, values, option_string=None):
+        deptype = dep.all_deptypes
+        if values:
+            deptype = tuple(x.strip() for x in values.split(','))
+            if deptype == ('all',):
+                deptype = 'all'
+            deptype = dep.canonical_deptype(deptype)
+
+        setattr(namespace, self.dest, deptype)
+
+
 _arguments['constraint'] = Args(
     'constraint', nargs=argparse.REMAINDER, action=ConstraintAction,
     help='constraint to select a subset of installed packages')
@@ -128,6 +142,11 @@ def default(self, value):
     dest='dirty',
     help='unset harmful variables in the build environment (default)')
 
+_arguments['deptype'] = Args(
+    '--deptype', action=DeptypeAction, default=dep.all_deptypes,
+    help="comma-separated list of deptypes to traverse\ndefault=%s"
+    % ','.join(dep.all_deptypes))
+
 _arguments['dirty'] = Args(
     '--dirty',
     action='store_true',

lib/spack/spack/cmd/dependencies.py

@@ -8,10 +8,11 @@
 import llnl.util.tty as tty
 from llnl.util.tty.colify import colify
 
-import spack.environment as ev
-import spack.store
-import spack.repo
 import spack.cmd
+import spack.cmd.common.arguments as arguments
+import spack.environment as ev
+import spack.repo
+import spack.store
 
 description = "show dependencies of a package"
 section = "basic"
@@ -26,6 +27,7 @@ def setup_parser(subparser):
     subparser.add_argument(
         '-t', '--transitive', action='store_true', default=False,
         help="show all transitive dependencies")
+    arguments.add_common_arguments(subparser, ['deptype'])
     subparser.add_argument(
         '-V', '--no-expand-virtuals', action='store_false', default=True,
         dest="expand_virtuals", help="do not expand virtual dependencies")
@@ -45,7 +47,7 @@ def dependencies(parser, args):
         format_string = '{name}{@version}{%compiler}{/hash:7}'
         tty.msg("Dependencies of %s" % spec.format(format_string, color=True))
         deps = spack.store.db.installed_relatives(
-            spec, 'children', args.transitive)
+            spec, 'children', args.transitive, deptype=args.deptype)
         if deps:
             spack.cmd.display_specs(deps, long=True)
         else:
@@ -63,9 +65,9 @@ def dependencies(parser, args):
 
         dependencies = set()
         for pkg in packages:
-            dependencies.update(
-                set(pkg.possible_dependencies(
-                    args.transitive, args.expand_virtuals)))
+            possible = pkg.possible_dependencies(
+                args.transitive, args.expand_virtuals, deptype=args.deptype)
+            dependencies.update(possible)
 
         if spec.name in dependencies:
             dependencies.remove(spec.name)

lib/spack/spack/database.py

@@ -875,7 +875,8 @@ def remove(self, spec):
             return self._remove(spec)
 
     @_autospec
-    def installed_relatives(self, spec, direction='children', transitive=True):
+    def installed_relatives(self, spec, direction='children', transitive=True,
+                            deptype='all'):
         """Return installed specs related to this one."""
         if direction not in ('parents', 'children'):
             raise ValueError("Invalid direction: %s" % direction)
@@ -883,11 +884,12 @@ def installed_relatives(self, spec, direction='children', transitive=True):
         relatives = set()
         for spec in self.query(spec):
             if transitive:
-                to_add = spec.traverse(direction=direction, root=False)
+                to_add = spec.traverse(
+                    direction=direction, root=False, deptype=deptype)
             elif direction == 'parents':
-                to_add = spec.dependents()
+                to_add = spec.dependents(deptype=deptype)
             else:  # direction == 'children'
-                to_add = spec.dependencies()
+                to_add = spec.dependencies(deptype=deptype)
 
             for relative in to_add:
                 hash_key = relative.dag_hash()

lib/spack/spack/test/cmd/dependencies.py

@@ -32,6 +32,20 @@ def test_transitive_dependencies(mock_packages):
     assert expected == actual
 
 
+def test_transitive_dependencies_with_deptypes(mock_packages):
+    out = dependencies('--transitive', '--deptype=link,run', 'dtbuild1')
+    deps = set(re.split(r'\s+', out.strip()))
+    assert set(['dtlink2', 'dtrun2']) == deps
+
+    out = dependencies('--transitive', '--deptype=build', 'dtbuild1')
+    deps = set(re.split(r'\s+', out.strip()))
+    assert set(['dtbuild2', 'dtlink2']) == deps
+
+    out = dependencies('--transitive', '--deptype=link', 'dtbuild1')
+    deps = set(re.split(r'\s+', out.strip()))
+    assert set(['dtlink2']) == deps
+
+
 @pytest.mark.db
 def test_immediate_installed_dependencies(mock_packages, database):
     with color_when(False):