edge case for #673

Signed-off-by: Kenneth Reitz <me@kennethreitz.org>

HISTORY.txt

@@ -1,3 +1,5 @@
+7.8.5:
+ - Edge case.
 7.8.4:
  - Flake8 checking with check --style!
 7.8.3:

pipenv/__version__.py

@@ -3,4 +3,4 @@
 #  //___/ / / / //___/ / //       //   / /  || / /
 # //       / / //       ((____   //   / /   ||/ /
 
-__version__ = '7.8.4'
+__version__ = '7.8.5'

pipenv/project.py

@@ -208,7 +208,11 @@ class Project(object):
                         data[section][package].update(_data)
 
             # We lose comments here, but it's for the best.)
-            return contoml.loads(toml.dumps(data, preserve=True))
+            try:
+                return contoml.loads(toml.dumps(data, preserve=True))
+            except RuntimeError:
+                return toml.loads(toml.dumps(data, preserve=True))
+
         else:
             # Fallback to toml parser, for large files.
             try: