Fixed issue #2888. Now the behaviour of pprint when working with nested

structures follows the common sense (and works like in 2.5 and 3.0).

Doc/library/pprint.rst

@@ -56,7 +56,7 @@ The :mod:`pprint` module defines one class:
       >>> stuff.insert(0, stuff[:])
       >>> pp = pprint.PrettyPrinter(indent=4)
       >>> pp.pprint(stuff)
-      [   [   'spam', 'eggs', 'lumberjack', 'knights', 'ni'],
+      [   ['spam', 'eggs', 'lumberjack', 'knights', 'ni'],
           'spam',
           'eggs',
           'lumberjack',

Lib/pprint.py

@@ -194,7 +194,7 @@ def _format(self, object, stream, indent, allowance, context, level):
             else:
                 write('(')
                 endchar = ')'
-            if self._indent_per_level > 1:
+            if self._indent_per_level > 1 and sepLines:
                 write((self._indent_per_level - 1) * ' ')
             if length:
                 context[objid] = 1

Lib/test/test_pprint.py

@@ -170,6 +170,17 @@ def test_basic_line_wrap(self):
         for type in [list, list2]:
             self.assertEqual(pprint.pformat(type(o), indent=4), exp)
 
+    def test_nested_indentations(self):
+        o1 = list(range(10))
+        o2 = dict(first=1, second=2, third=3)
+        o = [o1, o2]
+        expected = """\
+[   [0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
+    {   'first': 1,
+        'second': 2,
+        'third': 3}]"""
+        self.assertEqual(pprint.pformat(o, indent=4, width=42), expected)
+
     def test_sorted_dict(self):
         # Starting in Python 2.5, pprint sorts dict displays by key regardless
         # of how small the dictionary may be.

Misc/NEWS

@@ -108,6 +108,10 @@ Extension Modules
 Library
 -------
 
+- Issue #2888: Fixed the behaviour of pprint when working with nested
+  structures, to match the behaviour of 2.5 and 3.0 (now follows the common
+  sense).
+
 - Issue #3136: fileConfig()'s disabling of old loggers is now conditional via
   an optional disable_existing_loggers parameter, but the default value is
   such that the old behaviour is preserved. Thanks to Leandro Lucarella for