spack spec: add --reuse argument

4 files changed, 33 insertions, 16 deletions

diff --git a/lib/spack/spack/cmd/common/arguments.py b/lib/spack/spack/cmd/common/arguments.py
index 1b173bf584..bea8ccea90 100644
--- a/lib/spack/spack/cmd/common/arguments.py
+++ b/lib/spack/spack/cmd/common/arguments.py
@@ -320,3 +320,11 @@ the build yourself.  Format: %%Y%%m%%d-%%H%%M-[cdash-track]"""
         default=None,
         help=cdash_help['buildstamp']
     )
+
+
+@arg
+def reuse():
+    return Args(
+        '--reuse', action='store_true', default=False,
+        help='reuse installed dependencies'
+    )
diff --git a/lib/spack/spack/cmd/solve.py b/lib/spack/spack/cmd/solve.py
index 897eebfa4b..dc1fcf4ced 100644
--- a/lib/spack/spack/cmd/solve.py
+++ b/lib/spack/spack/cmd/solve.py
@@ -44,7 +44,8 @@ def setup_parser(subparser):
 
     # Below are arguments w.r.t. spec display (like spack spec)
     arguments.add_common_arguments(
-        subparser, ['long', 'very_long', 'install_status'])
+        subparser, ['long', 'very_long', 'install_status', 'reuse']
+    )
     subparser.add_argument(
         '-y', '--yaml', action='store_const', dest='format', default=None,
         const='yaml', help='print concrete spec as yaml')
@@ -68,9 +69,6 @@ def setup_parser(subparser):
         '--stats', action='store_true', default=False,
         help='print out statistics from clingo')
     subparser.add_argument(
-        '--reuse', action='store_true', default=False,
-        help='reuse installed dependencies')
-    subparser.add_argument(
         'specs', nargs=argparse.REMAINDER, help="specs of packages")
 
 
diff --git a/lib/spack/spack/cmd/spec.py b/lib/spack/spack/cmd/spec.py
index 592da60388..7c1375210a 100644
--- a/lib/spack/spack/cmd/spec.py
+++ b/lib/spack/spack/cmd/spec.py
@@ -28,7 +28,8 @@ for further documentation regarding the spec syntax, see:
     spack help --spec
 """
     arguments.add_common_arguments(
-        subparser, ['long', 'very_long', 'install_status'])
+        subparser, ['long', 'very_long', 'install_status', 'reuse']
+    )
     subparser.add_argument(
         '-y', '--yaml', action='store_const', dest='format', default=None,
         const='yaml', help='print concrete spec as YAML')
@@ -64,7 +65,7 @@ def spec(parser, args):
     name_fmt = '{namespace}.{name}' if args.namespaces else '{name}'
     fmt = '{@version}{%compiler}{compiler_flags}{variants}{arch=architecture}'
     install_status_fn = spack.spec.Spec.install_status
-    kwargs = {
+    tree_kwargs = {
         'cover': args.cover,
         'format': name_fmt + fmt,
         'hashlen': None if args.very_long else 7,
@@ -81,11 +82,15 @@ def spec(parser, args):
     if not args.specs:
         tty.die("spack spec requires at least one spec")
 
+    concretize_kwargs = {
+        'reuse': args.reuse
+    }
+
     for spec in spack.cmd.parse_specs(args.specs):
         # With -y, just print YAML to output.
         if args.format:
             if spec.name in spack.repo.path or spec.virtual:
-                spec.concretize()
+                spec.concretize(**concretize_kwargs)
 
             # The user can specify the hash type to use
             hash_type = getattr(ht, args.hash_type)
@@ -98,13 +103,13 @@ def spec(parser, args):
             continue
 
         with tree_context():
-            kwargs['hashes'] = False  # Always False for input spec
+            tree_kwargs['hashes'] = False  # Always False for input spec
             print("Input spec")
             print("--------------------------------")
-            print(spec.tree(**kwargs))
+            print(spec.tree(**tree_kwargs))
 
-            kwargs['hashes'] = args.long or args.very_long
+            tree_kwargs['hashes'] = args.long or args.very_long
             print("Concretized")
             print("--------------------------------")
-            spec.concretize()
-            print(spec.tree(**kwargs))
+            spec.concretize(**concretize_kwargs)
+            print(spec.tree(**tree_kwargs))
diff --git a/lib/spack/spack/spec.py b/lib/spack/spack/spec.py
index 08625eaa82..7268142537 100644
--- a/lib/spack/spack/spec.py
+++ b/lib/spack/spack/spec.py
@@ -2597,7 +2597,7 @@ class Spec(object):
             msg += "    For each package listed, choose another spec\n"
             raise SpecDeprecatedError(msg)
 
-    def _new_concretize(self, tests=False):
+    def _new_concretize(self, tests=False, reuse=False):
         import spack.solver.asp
 
         if not self.name:
@@ -2607,7 +2607,7 @@ class Spec(object):
         if self._concrete:
             return
 
-        result = spack.solver.asp.solve([self], tests=tests)
+        result = spack.solver.asp.solve([self], tests=tests, reuse=reuse)
         result.raise_if_unsat()
 
         # take the best answer
@@ -2625,17 +2625,23 @@ class Spec(object):
         self._dup(concretized)
         self._mark_concrete()
 
-    def concretize(self, tests=False):
+    def concretize(self, tests=False, reuse=False):
         """Concretize the current spec.
 
         Args:
             tests (bool or list): if False disregard 'test' dependencies,
                 if a list of names activate them for the packages in the list,
                 if True activate 'test' dependencies for all packages.
+            reuse (bool): if True try to maximize reuse of already installed
+                specs, if False don't account for installation status.
         """
         if spack.config.get('config:concretizer') == "clingo":
-            self._new_concretize(tests)
+            self._new_concretize(tests, reuse=reuse)
         else:
+            if reuse:
+                msg = ('maximizing reuse of installed specs is not '
+                       'possible with the original concretizer')
+                raise spack.error.SpecError(msg)
             self._old_concretize(tests)
 
     def _mark_root_concrete(self, value=True):