Add option to minimize full debug cores. include warning message about performance (#27970)

Co-authored-by: Harmen Stoppels <harmenstoppels@gmail.com>

4 files changed, 73 insertions, 21 deletions

diff --git a/lib/spack/spack/error.py b/lib/spack/spack/error.py
index be49656c07..700f4ea1d8 100644
--- a/lib/spack/spack/error.py
+++ b/lib/spack/spack/error.py
@@ -123,18 +123,11 @@ class UnsatisfiableSpecError(SpecError):
     For original concretizer, provide the requirement that was violated when
     raising.
     """
-    def __init__(self, provided, required=None, constraint_type=None, conflicts=None):
-        # required is only set by the original concretizer.
-        # clingo concretizer handles error messages differently.
-        if required is not None:
-            assert not conflicts  # can't mix formats
-            super(UnsatisfiableSpecError, self).__init__(
-                "%s does not satisfy %s" % (provided, required))
-        else:
-            indented = ['  %s\n' % conflict for conflict in conflicts]
-            conflict_msg = ''.join(indented)
-            msg = '%s is unsatisfiable, conflicts are:\n%s' % (provided, conflict_msg)
-            super(UnsatisfiableSpecError, self).__init__(msg)
+    def __init__(self, provided, required, constraint_type):
+        # This is only the entrypoint for old concretizer errors
+        super(UnsatisfiableSpecError, self).__init__(
+            "%s does not satisfy %s" % (provided, required))
+
         self.provided = provided
         self.required = required
         self.constraint_type = constraint_type
diff --git a/lib/spack/spack/main.py b/lib/spack/spack/main.py
index 86f5c76002..f41423fa1e 100644
--- a/lib/spack/spack/main.py
+++ b/lib/spack/spack/main.py
@@ -41,6 +41,7 @@ import spack.modules
 import spack.paths
 import spack.platforms
 import spack.repo
+import spack.solver.asp
 import spack.spec
 import spack.store
 import spack.util.debug
@@ -380,6 +381,13 @@ def make_argument_parser(**kwargs):
     # stat names in groups of 7, for nice wrapping.
     stat_lines = list(zip(*(iter(stat_names),) * 7))
 
+    # help message for --show-cores
+    show_cores_help = 'provide additional information on concretization failures\n'
+    show_cores_help += 'off (default): show only the violated rule\n'
+    show_cores_help += 'full: show raw unsat cores from clingo\n'
+    show_cores_help += 'minimized: show subset-minimal unsat cores '
+    show_cores_help += '(Warning: this may take hours for some specs)'
+
     parser.add_argument(
         '-h', '--help',
         dest='help', action='store_const', const='short', default=None,
@@ -404,6 +412,9 @@ def make_argument_parser(**kwargs):
         help="write out debug messages "
              "(more d's for more verbosity: -d, -dd, -ddd, etc.)")
     parser.add_argument(
+        '--show-cores', choices=["off", "full", "minimized"], default="off",
+        help=show_cores_help)
+    parser.add_argument(
         '--timestamp', action='store_true',
         help="Add a timestamp to tty output")
     parser.add_argument(
@@ -486,6 +497,13 @@ def setup_main_options(args):
         spack.config.set('config:debug', True, scope='command_line')
         spack.util.environment.tracing_enabled = True
 
+    if args.show_cores != "off":
+        # minimize_cores defaults to true, turn it off if we're showing full core
+        # but don't want to wait to minimize it.
+        spack.solver.asp.full_cores = True
+        if args.show_cores == 'full':
+            spack.solver.asp.minimize_cores = False
+
     if args.timestamp:
         tty.set_timestamp(True)
 
diff --git a/lib/spack/spack/solver/asp.py b/lib/spack/spack/solver/asp.py
index 4ad05cd9bf..957f363960 100644
--- a/lib/spack/spack/solver/asp.py
+++ b/lib/spack/spack/solver/asp.py
@@ -59,6 +59,14 @@ ASTType = None
 parse_files = None
 
 
+#: whether we should write ASP unsat cores quickly in debug mode when the cores
+#: may be very large or take the time (sometimes hours) to minimize them
+minimize_cores = True
+
+#: whether we should include all facts in the unsat cores or only error messages
+full_cores = False
+
+
 # backward compatibility functions for clingo ASTs
 def ast_getter(*names):
     def getter(node):
@@ -393,10 +401,12 @@ class Result(object):
         if len(constraints) == 1:
             constraints = constraints[0]
 
-        debug = spack.config.get('config:debug', False)
-        conflicts = self.format_cores() if debug else self.format_minimal_cores()
+        if minimize_cores:
+            conflicts = self.format_minimal_cores()
+        else:
+            conflicts = self.format_cores()
 
-        raise spack.error.UnsatisfiableSpecError(constraints, conflicts=conflicts)
+        raise UnsatisfiableSpecError(constraints, conflicts=conflicts)
 
     @property
     def specs(self):
@@ -512,10 +522,9 @@ class PyclingoDriver(object):
 
         atom = self.backend.add_atom(symbol)
 
-        # in debug mode, make all facts choices/assumptions
-        # otherwise, only if we're generating cores and assumption=True
-        debug = spack.config.get('config:debug', False)
-        choice = debug or (self.cores and assumption)
+        # with `--show-cores=full or --show-cores=minimized, make all facts
+        # choices/assumptions, otherwise only if assumption=True
+        choice = self.cores and (full_cores or assumption)
 
         self.backend.add_rule([atom], [], choice=choice)
         if choice:
@@ -2044,3 +2053,33 @@ def solve(specs, dump=(), models=0, timers=False, stats=False, tests=False,
     return driver.solve(
         setup, specs, dump, models, timers, stats, tests, reuse
     )
+
+
+class UnsatisfiableSpecError(spack.error.UnsatisfiableSpecError):
+    """
+    Subclass for new constructor signature for new concretizer
+    """
+    def __init__(self, provided, conflicts):
+        indented = ['  %s\n' % conflict for conflict in conflicts]
+        conflict_msg = ''.join(indented)
+        issue = 'conflicts' if full_cores else 'errors'
+        msg = '%s is unsatisfiable, %s are:\n%s' % (provided, issue, conflict_msg)
+
+        newline_indent = '\n    '
+        if not full_cores:
+            msg += newline_indent + 'To see full clingo unsat cores, '
+            msg += 're-run with `spack --show-cores=full`'
+        if not minimize_cores or not full_cores:
+            # not solver.minimalize_cores and not solver.full_cores impossible
+            msg += newline_indent + 'For full, subset-minimal unsat cores, '
+            msg += 're-run with `spack --show-cores=minimized'
+            msg += newline_indent
+            msg += 'Warning: This may take (up to) hours for some specs'
+
+        super(spack.error.UnsatisfiableSpecError, self).__init__(msg)
+
+        self.provided = provided
+
+        # Add attribute expected of the superclass interface
+        self.required = None
+        self.constraint_type = None
diff --git a/lib/spack/spack/test/concretize.py b/lib/spack/spack/test/concretize.py
index 5e9188b888..179a4e26d8 100644
--- a/lib/spack/spack/test/concretize.py
+++ b/lib/spack/spack/test/concretize.py
@@ -557,11 +557,13 @@ class TestConcretize(object):
         with pytest.raises(spack.error.SpackError):
             s.concretize()
 
-    def test_conflicts_new_concretizer_debug(self, conflict_spec, mutable_config):
+    def test_conflicts_show_cores(self, conflict_spec, monkeypatch):
         if spack.config.get('config:concretizer') == 'original':
             pytest.skip('Testing debug statements specific to new concretizer')
 
-        spack.config.set('config:debug', True)
+        monkeypatch.setattr(spack.solver.asp, 'full_cores', True)
+        monkeypatch.setattr(spack.solver.asp, 'minimize_cores', False)
+
         s = Spec(conflict_spec)
         with pytest.raises(spack.error.SpackError) as e:
             s.concretize()