More input validation

Author: WardBrian

cmdstanpy/model.py

@@ -1714,6 +1714,10 @@ def laplace_sample(
                 "Method 'laplace_sample' not available for CmdStan versions "
                 "before 2.32"
             )
+        if opt_args is not None and mode is not None:
+            raise ValueError(
+                "Cannot specify both 'opt_args' and 'mode' arguments"
+            )
         if mode is None:
             optimize_args = {
                 "seed": seed,

cmdstanpy/stanfit/laplace.py

@@ -32,7 +32,6 @@
 from .runset import RunSet
 
 # TODO list:
-# - tests
 # - docs and example notebook
 # - make sure features like standalone GQ are updated/working
 
@@ -57,7 +56,6 @@ def _assemble_draws(self) -> None:
         if self._draws.shape != (0,):
             return
 
-        # TODO: should we fake a chain dimension?
         with open(self._runset.csv_files[0], 'r') as fd:
             lines = (line for line in fd if not line.startswith('#'))
             self._draws = np.loadtxt(

test/test_laplace.py

@@ -46,6 +46,18 @@ def test_laplace_bad_jacobian_mismatch():
         )
 
 
+def test_laplace_bad_two_modes():
+    model_file = os.path.join(DATAFILES_PATH, 'optimize', 'rosenbrock.stan')
+    model = cmdstanpy.CmdStanModel(stan_file=model_file)
+    with pytest.raises(ValueError):
+        model.laplace_sample(
+            data={},
+            mode=os.path.join(DATAFILES_PATH, 'optimize', 'rosenbrock_mle.csv'),
+            opt_args={'iter': 1003},
+            jacobian=False,
+        )
+
+
 def test_laplace_outputs():
     model_file = os.path.join(DATAFILES_PATH, 'optimize', 'rosenbrock.stan')
     model = cmdstanpy.CmdStanModel(stan_file=model_file)