Don't allow replacement of root develop specs with --reuse (#28605)

* Fix to concretize.lp

do not allow dev specs to be reused

Co-authored-by: Gregory Becker <becker33@llnl.gov>

lib/spack/spack/solver/asp.py

@@ -1676,13 +1676,15 @@ def define_installed_packages(self, specs, possible):
         # Specs from local store
         with spack.store.db.read_transaction():
             for spec in spack.store.db.query(installed=True):
-                self._facts_from_concrete_spec(spec, possible)
+                if not spec.satisfies('dev_path=*'):
+                    self._facts_from_concrete_spec(spec, possible)
 
         # Specs from configured buildcaches
         try:
             index = spack.binary_distribution.update_cache_and_get_specs()
             for spec in index:
-                self._facts_from_concrete_spec(spec, possible)
+                if not spec.satisfies('dev_path=*'):
+                    self._facts_from_concrete_spec(spec, possible)
         except (spack.binary_distribution.FetchCacheError, IndexError):
             # this is raised when no mirrors had indices.
             # TODO: update mirror configuration so it can indicate that the source cache

lib/spack/spack/solver/concretize.lp

@@ -853,6 +853,9 @@ no_flags(Package, FlagType)
 { hash(Package, Hash) : installed_hash(Package, Hash) } 1
  :- node(Package), error("Internal error: package must resolve to at most one hash").
 
+% you can't choose an installed hash for a dev spec
+:- hash(Package, Hash), variant_value(Package, "dev_path", _).
+
 % if a hash is selected, we impose all the constraints that implies
 impose(Hash) :- hash(Package, Hash).
 

lib/spack/spack/test/concretize.py

@@ -339,7 +339,6 @@ def concretize_difficult_packages(self, a, b):
         assert s[a].version == ver(b)
 
     def test_concretize_two_virtuals(self):
-
         """Test a package with multiple virtual dependencies."""
         Spec('hypre').concretize()
 
@@ -1165,6 +1164,46 @@ def test_external_package_versions(self, spec_str, is_external, expected):
         assert s.external == is_external
         assert s.satisfies(expected)
 
+    @pytest.mark.parametrize('dev_first', [True, False])
+    @pytest.mark.parametrize('spec', [
+        'dev-build-test-install', 'dev-build-test-dependent ^dev-build-test-install'])
+    @pytest.mark.parametrize('mock_db', [True, False])
+    def test_reuse_does_not_overwrite_dev_specs(
+            self, dev_first, spec, mock_db, tmpdir, monkeypatch):
+        """Test that reuse does not mix dev specs with non-dev specs.
+
+        Tests for either order (dev specs are not reused for non-dev, and
+        non-dev specs are not reused for dev specs)
+        Tests for a spec in which the root is developed and a spec in
+        which a dep is developed.
+        Tests for both reuse from database and reuse from buildcache"""
+        # dev and non-dev specs that are otherwise identical
+        spec = Spec(spec)
+        dev_spec = spec.copy()
+        dev_constraint = 'dev_path=%s' % tmpdir.strpath
+        dev_spec['dev-build-test-install'].constrain(dev_constraint)
+
+        # run the test in both orders
+        first_spec = dev_spec if dev_first else spec
+        second_spec = spec if dev_first else dev_spec
+
+        # concretize and setup spack to reuse in the appropriate manner
+        first_spec.concretize()
+
+        def mock_fn(*args, **kwargs):
+            return [first_spec]
+
+        if mock_db:
+            monkeypatch.setattr(spack.store.db, 'query', mock_fn)
+        else:
+            monkeypatch.setattr(
+                spack.binary_distribution, 'update_cache_and_get_specs', mock_fn)
+
+        # concretize and ensure we did not reuse
+        with spack.config.override("concretizer:reuse", True):
+            second_spec.concretize()
+        assert first_spec.dag_hash() != second_spec.dag_hash()
+
     @pytest.mark.regression('20292')
     @pytest.mark.parametrize('context', [
         {'add_variant': True, 'delete_variant': False},
@@ -1172,7 +1211,7 @@ def test_external_package_versions(self, spec_str, is_external, expected):
         {'add_variant': True, 'delete_variant': True}
     ])
     @pytest.mark.xfail()
-    def test_reuse_installed_packages(
+    def test_reuse_installed_packages_when_package_def_changes(
             self, context, mutable_database, repo_with_changing_recipe
     ):
         # Install a spec