feat: added functionality to use pathlib.Path object in result_file_name option and when loading results

Author: PeterMeisrimelModelon

CHANGELOG

@@ -8,6 +8,7 @@
         * Paths when loading FMUs
         * `log_file_name` when loading FMUs
         * `pyfmi.common.log.parse_xml_log` & `extract_xml_log`, including `fmu.extract_xml_log()`.
+        * `result_file_name` as simulation option and manual use of `ResultReader` classes
 
 --- PyFMI-2.20.1 ---
     * Resolved issue where caching in result handling was too persistent and could prevent automatic garbage collection.

src/common/io.py

@@ -28,6 +28,7 @@
 from shutil import disk_usage
 import abc
 import warnings
+from pathlib import Path
 
 import numpy as np
 import scipy
@@ -388,7 +389,7 @@ def __init__(self, filename, delimiter=";"):
                 Default: ";""
         """
 
-        if isinstance(filename, str):
+        if isinstance(filename, (str, Path)):
             try:
                 fid = codecs.open(filename,'r','utf-8')
             except FileNotFoundError as e:
@@ -997,7 +998,8 @@ def __init__(self,fname):
                 Name of file or stream object which the result is written to.
                 If fname is a stream, it needs to support 'readline' and 'seek'.
         """
-        if isinstance(fname, str):
+        if isinstance(fname, (str, Path)):
+            fname = os.path.abspath(fname)
             try:
                 fid = codecs.open(fname,'r','utf-8')
             except FileNotFoundError as e:
@@ -1302,8 +1304,8 @@ def __init__(self, fname, delayed_trajectory_loading = True, allow_file_updates=
                 Default: False
         """
 
-        if isinstance(fname, str):
-            self._fname = fname
+        if isinstance(fname, (str, Path)):
+            self._fname = os.path.abspath(fname)
             self._is_stream = False
         elif hasattr(fname, "name") and os.path.isfile(fname.name):
             self._fname = fname.name
@@ -2134,7 +2136,7 @@ def simulation_start(self):
                         cont_alias_bool.append(-1 if var.alias == fmi.FMI_NEGATED_ALIAS else 1)
 
         # Open file
-        if isinstance(self.file_name, str):
+        if isinstance(self.file_name, (str, Path)):
             f = codecs.open(self.file_name,'w','utf-8')
             self.file_open = True
         else:
@@ -2254,7 +2256,7 @@ def file_name(self):
     @cached_property
     def _is_stream(self):
         file = self.file_name
-        if isinstance(file, str):
+        if isinstance(file, (str, Path)):
             return False
         else:
             if not (hasattr(file, 'write') and hasattr(file, 'seek')):
@@ -2899,7 +2901,7 @@ def simulation_start(self, diagnostics_params={}, diagnostics_vars={}):
 
         # Open file
         file_name = self.file_name
-        if isinstance(self.file_name, str):
+        if isinstance(self.file_name, (str, Path)):
             self._file = open(file_name,'wb')
         else:
             if not (hasattr(self.file_name, 'write') and hasattr(self.file_name, 'seek') and (hasattr(self.file_name, 'tell'))):
@@ -3177,7 +3179,7 @@ def __init__(self, fname):
                 which the result is written to.
         """
 
-        if isinstance(fname, str):
+        if isinstance(fname, (str, Path)):
             self._fname = fname
         elif hasattr(fname, "name") and os.path.isfile(fname.name):
             self._fname = fname.name

tests/test_fmi.py

@@ -147,6 +147,15 @@ def test_extract_xml_log_as_path(self, load_with_path_object):
         fmu = load_with_path_object.loader(str(load_with_path_object.path))
         fmu.extract_xml_log(Path("xml_log.xml"))
 
+    def test_result_file_name_as_path(self, load_with_path_object):
+        fmu = load_with_path_object.loader(str(load_with_path_object.path))
+        opts = fmu.simulate_options()
+        opts["ncp"] = 1 # speed
+        if opts.get("solver"): # work-around for an FMI1 bug with absolute tolerance adjustments
+            opts["solver"] = "ExplicitEuler"
+        opts["result_file_name"] = Path("res.mat")
+        fmu.simulate(options = opts)
+
 @pytest.mark.parametrize("fmu_loader, fmu_path",
     [
         (FMUModelME1, PATH_TO_FMU_EXAMPLES/ 'ME1.0' / 'bouncingBall.fmu'),

tests/test_io.py

@@ -2739,3 +2739,25 @@ def test_given_no_start_simulation_when_get_result_then_no_result_error(result_h
 
     with pytest.raises(NoResultError):
         result_handler.get_result()
+
+@pytest.mark.parametrize("result_reader_class, result_handling, suffix", [
+    (ResultDymolaBinary, "binary", ".mat"),
+    (ResultReaderBinaryMat, "binary", ".mat"),
+    (lambda x: ResultCSVTextual(x, delimiter=","), "csv", ".csv"),
+    (ResultDymolaTextual, "file", ".txt")
+])
+def test_load_results_files_via_path_object(
+    tmp_path,
+    result_reader_class,
+    result_handling,
+    suffix
+):
+    # Functionality itself is FMI agnostic; FMI2 supports most types
+    fmu = load_fmu(FMI2_REF_FMU_PATH / "VanDerPol.fmu")
+    opts = fmu.simulate_options()
+    opts["ncp"] = 0 # speed
+    res_file = Path(tmp_path) / f"res_file{suffix}"
+    opts["result_file_name"] = res_file
+    opts["result_handling"] = result_handling
+    fmu.simulate(options = opts)
+    result_reader_class(res_file)