FEM: solver elmer, workaround for result reading

src/Mod/Fem/femsolver/elmer/tasks.py

@@ -133,7 +133,7 @@ class Results(run.Results):
     def run(self):
         if self.solver.ElmerResult is None:
             self._createResults()
-        postPath = os.path.join(self.directory, "case0001.vtu")
+        postPath = self._getResultFile()
         self.solver.ElmerResult.read(postPath)
         self.solver.ElmerResult.getLastPostObject().touch()
         self.solver.Document.recompute()
@@ -144,4 +144,20 @@ def _createResults(self):
         self.solver.ElmerResult.Label = self.solver.Label + "Result"
         self.analysis.addObject(self.solver.ElmerResult)
 
+    def _getResultFile(self):
+        postPath = None
+        # elmer post file path changed with version x.x
+        # see https://forum.freecadweb.org/viewtopic.php?f=18&t=42732
+        # workaround
+        possible_post_file_0 = os.path.join(self.directory, "case0001.vtu")
+        possible_post_file_t = os.path.join(self.directory, "case_t0001.vtu")
+        if os.path.isfile(possible_post_file_0):
+            postPath = possible_post_file_0
+        elif os.path.isfile(possible_post_file_t):
+            postPath = possible_post_file_t
+        else:
+            self.report.error("Result file not found.")
+            self.fail()
+        return postPath
+
 ##  @}