Merge lp:~cjwatson/lazr.restful/py3-path-parts into lp:lazr.restful

[Colin Watson]

Fix __path_parts__ error handling for Python 3.

On Python 3, str objects have an __iter__ method. Fix MultiplePathPartAbsoluteURL.__str__ to account for that.

[Cristian Gonzalez (cristiangsp)]

Good catch!

review: Approve

=== modified file 'src/lazr/restful/docs/absoluteurl.rst'
--- src/lazr/restful/docs/absoluteurl.rst	2020-02-04 11:52:59 +0000
+++ src/lazr/restful/docs/absoluteurl.rst	2021-01-19 10:30:21 +0000
@@ -205,7 +205,13 @@
     >>> str(getMultiAdapter((resource, request), IAbsoluteURL))
     Traceback (most recent call last):
     ...
-    TypeError: Expected an iterable for __path_parts__.
+    TypeError: Expected an iterable of strings for __path_parts__.
+
+    >>> resource.__path_parts__ = 0
+    >>> str(getMultiAdapter((resource, request), IAbsoluteURL))
+    Traceback (most recent call last):
+    ...
+    TypeError: Expected an iterable of strings for __path_parts__.
 
 If the __parent__ or __path_parts__ is missing or None, an attempt to
 get the URL raises the same exception as AbsoluteURL does.

=== modified file 'src/lazr/restful/simple.py'
--- src/lazr/restful/simple.py	2020-07-22 23:22:26 +0000
+++ src/lazr/restful/simple.py	2021-01-19 10:30:21 +0000
@@ -20,6 +20,7 @@
 
 import traceback
 
+import six
 from six.moves.urllib.parse import (
     quote,
     unquote,
@@ -370,8 +371,10 @@
         parts = getattr(self.context, '__path_parts__', None)
         if parts is None:
             raise TypeError(_insufficientContext)
-        if not hasattr(parts, '__iter__'):
-            raise TypeError("Expected an iterable for __path_parts__.")
+        if (isinstance(parts, six.string_types) or
+                not hasattr(parts, '__iter__')):
+            raise TypeError(
+                "Expected an iterable of strings for __path_parts__.")
 
         escaped_parts = [quote(part.encode('utf-8'), _safe) for part in parts]
         return start_url + "/" + "/".join(escaped_parts)