Avoid replacing symlinked spack.yaml when concretizing an environment (#26428)

2 files changed, 20 insertions, 1 deletions

diff --git a/lib/spack/spack/environment.py b/lib/spack/spack/environment.py
index 7a9a4735fc..330d90915e 100644
--- a/lib/spack/spack/environment.py
+++ b/lib/spack/spack/environment.py
@@ -1944,7 +1944,7 @@ class Environment(object):
         written = os.path.exists(self.manifest_path)
         if changed or not written:
             self.raw_yaml = copy.deepcopy(self.yaml)
-            with fs.write_tmp_and_move(self.manifest_path) as f:
+            with fs.write_tmp_and_move(os.path.realpath(self.manifest_path)) as f:
                 _write_yaml(self.yaml, f)
 
     def __enter__(self):
diff --git a/lib/spack/spack/test/cmd/env.py b/lib/spack/spack/test/cmd/env.py
index d9d6f5483c..10b9dee981 100644
--- a/lib/spack/spack/test/cmd/env.py
+++ b/lib/spack/spack/test/cmd/env.py
@@ -248,6 +248,25 @@ def test_env_install_same_spec_twice(install_mockery, mock_fetch):
         assert 'already installed' in out
 
 
+def test_env_definition_symlink(install_mockery, mock_fetch, tmpdir):
+    filepath = str(tmpdir.join('spack.yaml'))
+    filepath_mid = str(tmpdir.join('spack_mid.yaml'))
+
+    env('create', 'test')
+    e = ev.read('test')
+    e.add('mpileaks')
+
+    os.rename(e.manifest_path, filepath)
+    os.symlink(filepath, filepath_mid)
+    os.symlink(filepath_mid, e.manifest_path)
+
+    e.concretize()
+    e.write()
+
+    assert os.path.islink(e.manifest_path)
+    assert os.path.islink(filepath_mid)
+
+
 def test_env_install_two_specs_same_dep(
         install_mockery, mock_fetch, tmpdir, capsys):
     """Test installation of two packages that share a dependency with no