TST: cover the branch a first run actually takes

samefile needs both files to exist, and every case here wrote one first, so the
resolved-path fallback that a run with no logs yet goes through was never
exercised. Replacing it with False leaves the new test red.

Signed-off-by: thc1006 <84045975+thc1006@users.noreply.github.com>

Author: thc1006

monte_carlo_test.errors.txt

@@ -5,8 +5,8 @@
 import os
 import re
 import warnings
-from collections import namedtuple
 from collections.abc import Mapping
+from collections import namedtuple
 from datetime import datetime
 
 import netCDF4

monte_carlo_test.inputs.txt

@@ -6,6 +6,7 @@
 from rocketpy.motors import CylindricalTank, Fluid, HybridMotor
 from rocketpy.motors.tank import MassFlowRateBasedTank
 
+
 MEASURED_APOGEE_AGL = 9308.32
 MAX_RELATIVE_APOGEE_ERROR = 0.01
 REFERENCE_MAX_SPEED = 444.24

monte_carlo_test.outputs.txt

@@ -2,9 +2,9 @@
 import os
 from datetime import datetime
 
-import netCDF4
 import numpy as np
 import numpy.testing as npt
+import netCDF4
 import pytest
 import pytz
 

rocketpy/environment/environment.py

@@ -763,3 +763,19 @@ def test_a_newline_in_the_separators_is_refused_too(tmp_path):
 def test_export_options_that_keep_one_line_are_left_alone(tmp_path, harmless):
     """Only what puts a newline inside a record is refused."""
     _refuse_logs_this_run_cannot_write(*_three_logs(tmp_path), harmless)
+
+
+def test_two_names_for_a_file_that_does_not_exist_yet_are_still_one_file(tmp_path):
+    """``samefile`` needs both to exist, and a first run has created neither.
+
+    Every other case here writes the file first, so the resolved-path branch
+    that a first run actually takes was never exercised.
+    """
+    (tmp_path / "sub").mkdir()
+    missing = str(tmp_path / "run.inputs.txt")
+    same_by_another_name = str(tmp_path / "sub" / ".." / "run.inputs.txt")
+    errors = str(tmp_path / "run.errors.txt")
+
+    assert not pathlib.Path(missing).exists()
+    with pytest.raises(ValueError, match="same file"):
+        _refuse_logs_this_run_cannot_write(missing, same_by_another_name, errors)

tests/acceptance/test_defiance_rocket.py

@@ -3,8 +3,8 @@
 import numpy as np
 import pytest
 
-from rocketpy.rocket.parachute import Parachute
 from rocketpy.stochastic import StochasticParachute
+from rocketpy.rocket.parachute import Parachute
 
 
 def test_stochastic_parachute_create_object(stochastic_main_parachute):

tests/unit/environment/test_environment.py

@@ -22,6 +22,7 @@
     tuple_handler,
 )
 
+
 WEB_MERCATOR_EARTH_RADIUS = 6378137.0