Further mods to `Forward.__str__` to possibly address memory issues reported in #85 and #91, and also does not stomp on user-defined expression names

2 files changed, 11 insertions, 7 deletions

diff --git a/pyparsing.py b/pyparsing.py
index 93efe48..febefc2 100644
--- a/pyparsing.py
+++ b/pyparsing.py
@@ -96,7 +96,7 @@ classes inherit from. Use the docstrings for examples of how to:
 """
 
 __version__ = "2.4.1"
-__versionTime__ = "05 Jul 2019 04:57 UTC"
+__versionTime__ = "05 Jul 2019 15:20 UTC"
 __author__ = "Paul McGuire <ptmcg@users.sourceforge.net>"
 
 import string
@@ -4793,19 +4793,22 @@ class Forward(ParseElementEnhance):
     def __str__( self ):
         if hasattr(self, "name"):
             return self.name
+        if self.strRepr is not None:
+            return self.strRepr
 
-        # Avoid infinite recursion by setting a temporary name
-        self.name = self.__class__.__name__ + ": ..."
+        # Avoid infinite recursion by setting a temporary strRepr
+        self.strRepr = ": ..."
 
         # Use the string representation of main expression.
+        retString = '...'
         try:
             if self.expr is not None:
-                retString = _ustr(self.expr)
+                retString = _ustr(self.expr)[:1000]
             else:
                 retString = "None"
         finally:
-            self.name = self.__class__.__name__ + ": " + retString
-        return self.name
+            self.strRepr = self.__class__.__name__ + ": " + retString
+        return self.strRepr
 
     def copy(self):
         if self.expr is not None:
diff --git a/unitTests.py b/unitTests.py
index 52ad305..6411350 100644
--- a/unitTests.py
+++ b/unitTests.py
@@ -2981,7 +2981,7 @@ class SetNameTest(ParseTestCase):
             + | - term
             Forward: ?: term
             ?: term
-            Forward: {a | b | c [{d | e | f Forward: ...}]...}
+            Forward: {a | b | c [{d | e | f : ...}]...}
             int [, int]...
             (len) int...
             nested () expression
@@ -2992,6 +2992,7 @@ class SetNameTest(ParseTestCase):
 
         for t,e in zip(tests, expected):
             tname = str(t)
+            print_(tname)
             self.assertEqual(tname, e, "expression name mismatch, expected {0} got {1}".format(e, tname))
 
 class TrimArityExceptionMaskingTest(ParseTestCase):