diff --git a/lib/spack/spack/test/concretize.py b/lib/spack/spack/test/concretize.py
index fc24a1d9724..6aa90a375b9 100644
--- a/lib/spack/spack/test/concretize.py
+++ b/lib/spack/spack/test/concretize.py
@@ -2,6 +2,7 @@
 # Spack Project Developers. See the top-level COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
+import os
 import sys
 
 import jinja2
@@ -1138,6 +1139,44 @@ def test_external_package_versions(self, spec_str, is_external, expected):
         assert s.external == is_external
         assert s.satisfies(expected)
 
+    def test_reuse_does_not_overwrite_root_dev_specs(self, tmpdir, mock_packages, install_mockery, mock_fetch):
+        with tmpdir.as_cwd():
+            # potential parameters
+            package_name = 'dev-build-test-install'
+            package_version = '0.0.0'
+            # have to setup paths to get concretization to work
+            dev_path = '%s/%s' % (tmpdir.strpath, package_name)
+            os.makedirs(dev_path)
+            spec_str = package_name
+            dev_spec_str = '%s@%s dev_path=%s' % (package_name,
+                                                  package_version, dev_path)
+            # concretize and install a non-dev version
+            s = Spec(spec_str).concretized()
+            s.package.do_install(fake=True)
+            # concretize a dev version
+            dev_spec = Spec(dev_spec_str).concretized(reuse=True)
+            assert dev_spec.dag_hash() is not s.dag_hash()
+
+    def test_reuse_does_not_overwrite_dependent_dev_specs(self, tmpdir, mock_packages, install_mockery, mock_fetch):
+        with tmpdir.as_cwd():
+            # potential parameters
+            root_spec = 'dev-build-test-dependent'
+            package_name = 'dev-build-test-install'
+            package_version = '0.0.0'
+            # have to setup paths to get concretization to work
+            dev_path = '%s/%s' % (tmpdir.strpath, package_name)
+            os.makedirs(dev_path)
+            spec_str = root_spec
+            dev_spec_str = '%s ^%s@%s dev_path=%s' % (root_spec, package_name,
+                                                      package_version, dev_path)
+            # concretize and install a non-dev version
+            s = Spec(spec_str).concretized()
+            s.package.do_install(fake=True)
+            # concretize a dev version
+            dev_spec = Spec(dev_spec_str).concretized(reuse=True)
+            assert dev_spec.dag_hash() is not s.dag_hash()
+
+
     @pytest.mark.regression('20292')
     @pytest.mark.parametrize('context', [
         {'add_variant': True, 'delete_variant': False},
@@ -1145,7 +1184,7 @@ 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