Raise exception for extremely long files names greater than 1000 characters

Author: mattpitkin

pymultinest/run.py

@@ -235,13 +235,16 @@ def dumper(nSamples,nlive,nPar,
 	# we need to make local copies here that are not thrown away
 	s = outputfiles_basename.encode()
 
-	if len(outputfiles_basename + "post_equal_weights.txt") > 100:
+	if len(outputfiles_basename + "post_equal_weights.txt") < 100:
+		# 100 characters work for all MultiNest versions
+		sb = create_string_buffer(s, 100)
+	elif len(outputfiles_basename + "post_equal_weights.txt") > 1000:
+		# file name is too long
+		raise ValueError("Filenames must be less than 1000 characters long.")
+	else:
 		# try 1000 character length file name (this may cause MultiNest failure
 		# or filename truncation if not using the latest MultiNest version)
 		sb = create_string_buffer(s, 1000)
-	else:
-		# 100 characters work for all MultiNest versions
-		sb = create_string_buffer(s, 100)
 
 	argtypes = [c_bool, c_bool, c_bool, 
 		c_int, c_double, c_double, 

tests/pymultinest_extremely_long_name.py

@@ -0,0 +1,11 @@
+# Script to test MultiNest failure when running with an extremely long file name (> than 1000 characters)
+
+import pytest
+from pymultinest.solve import solve
+
+def test():
+    with pytest.raises(ValueError):
+        solve(lambda cube: -0.5 *(cube**2).sum(), lambda cube: cube, 2, 
+              resume=True, verbose=True,
+              outputfiles_basename=1100*"a")
+