FIX: do not print dev_head_t if not available (#13741)

Co-authored-by: Eric Larson <larson.eric.d@gmail.com>

Author: sappelhoff

mne/dipole.py

@@ -1569,6 +1569,11 @@ def fit_dipole(
     safe_false = _verbose_safe_false()
     bem = _setup_bem(bem, bem_extra, neeg, mri_head_t, verbose=safe_false)
     if not bem["is_sphere"]:
+        if trans == "identity":  # = trans was passed as None
+            raise ValueError(
+                "`trans` is ``None``, but bem model is not spherical. "
+                "You must pass a valid `trans` in this case."
+            )
         # Find the best-fitting sphere
         inner_skull = _bem_find_surface(bem, "inner_skull")
         inner_skull = inner_skull.copy()
@@ -1652,7 +1657,8 @@ def fit_dipole(
     logger.info("")
 
     _print_coord_trans(mri_head_t)
-    _print_coord_trans(info["dev_head_t"])
+    if info["dev_head_t"]:
+        _print_coord_trans(info["dev_head_t"])
     logger.info(f"{len(info['bads'])} bad channels total")
 
     # Forward model setup (setup_forward_model from setup.c)

mne/tests/test_dipole.py

@@ -365,6 +365,8 @@ def test_min_distance_fit_dipole():
 
     with pytest.raises(ValueError, match="min_dist should be positive"):
         fit_dipole(evoked, cov, fname_bem, fname_trans, -1.0)
+    with pytest.raises(ValueError, match="not spherical"):
+        fit_dipole(evoked, cov, bem, trans=None)
 
 
 def _compute_depth(dip, fname_bem, fname_trans, subject, subjects_dir):

tools/install_pre_requirements.sh

@@ -32,10 +32,9 @@ python -m pip install $STD_ARGS --only-binary ":all:" --default-timeout=60 \
 	"tables>=3.10.3.dev0" \
 	"pyarrow>=22.0.0.dev0" \
 	"matplotlib>=3.11.0.dev0" \
+	"statsmodels>=0.15.0.dev0" \
 	"h5py>=3.13.0"
-	# "statsmodels>=0.15.0.dev697"
 echo "::endgroup::"
-# No statsmodels because of https://github.com/MacPython/statsmodels-wheels/issues/202
 # No Numba because it forces an old NumPy version
 
 echo "::group::VTK"