Don't warn with 'bad-format-character' when encountering the 'a' format on Python 3.

7 files changed, 25 insertions, 3 deletions

diff --git a/ChangeLog b/ChangeLog
index 9b675d0..6f780b8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -4,6 +4,9 @@ ChangeLog for Pylint
 --
     * Fix unused-import false positive with Python 3 metaclasses (#143).
 
+    * Don't warn with 'bad-format-character' when encountering
+      the 'a' format on Python 3.
+
 2014-04-30  --  1.2.1
     * Restore the ability to specify the init-hook option via the
       configuration file, which was accidentally broken in 1.2.0.
diff --git a/checkers/utils.py b/checkers/utils.py
index e7d85d4..6f40538 100644
--- a/checkers/utils.py
+++ b/checkers/utils.py
@@ -19,6 +19,7 @@
 """
 
 import re
+import sys
 import string
 
 import astroid
@@ -28,6 +29,7 @@ from logilab.common.compat import builtins
 BUILTINS_NAME = builtins.__name__
 
 COMP_NODE_TYPES = astroid.ListComp, astroid.SetComp, astroid.DictComp, astroid.GenExpr
+PY3K = sys.version_info[0] == 3
 
 
 class NoSuchArgumentError(Exception):
@@ -345,7 +347,11 @@ def parse_format_string(format_string):
             if char in 'hlL':
                 i, char = next_char(i)
             # Parse the conversion type (mandatory).
-            if char not in 'diouxXeEfFgGcrs%':
+            if PY3K:
+                flags = 'diouxXeEfFgGcrs%a'
+            else:
+                flags = 'diouxXeEfFgGcrs%'
+            if char not in flags:
                 raise UnsupportedFormatCharacter(i)
             if key:
                 keys.add(key)
diff --git a/test/input/func_e12xx.py b/test/input/func_e12xx.py
index 6482c92..83df7ab 100644
--- a/test/input/func_e12xx.py
+++ b/test/input/func_e12xx.py
@@ -14,7 +14,7 @@ def pprint():
     logging.info('', '') # 1205
     logging.info('%s%', '') # 1201
     logging.info('%s%s', '') # 1206
-    logging.info('%s%a', '', '') # 1200
+    logging.info('%s%y', '', '') # 1200
     logging.info('%s%s', '', '', '') # 1205
 
     # These should be okay:
diff --git a/test/input/func_e13xx.py b/test/input/func_e13xx.py
index a0d39ef..1eaf598 100644
--- a/test/input/func_e13xx.py
+++ b/test/input/func_e13xx.py
@@ -18,4 +18,5 @@ def pprint():
     print "%(PARG_1)d %(PARG_2)d" % [2, 3] # 1303
     print "%2z" % PARG_1
     print "strange format %2" % PARG_2
+    print "works in 3 %a" % 1
 
diff --git a/test/messages/func_e12xx.txt b/test/messages/func_e12xx.txt
index 690e6f4..d0a8b9c 100644
--- a/test/messages/func_e12xx.txt
+++ b/test/messages/func_e12xx.txt
@@ -2,5 +2,5 @@ E: 13:pprint: Too many arguments for logging format string
 E: 14:pprint: Too many arguments for logging format string
 E: 15:pprint: Logging format string ends in middle of conversion specifier
 E: 16:pprint: Not enough arguments for logging format string
-E: 17:pprint: Unsupported logging format character 'a' (0x61) at index 3
+E: 17:pprint: Unsupported logging format character 'y' (0x79) at index 3
 E: 18:pprint: Too many arguments for logging format string
diff --git a/test/messages/func_e13xx.txt b/test/messages/func_e13xx.txt
index c130949..f2d0d36 100644
--- a/test/messages/func_e13xx.txt
+++ b/test/messages/func_e13xx.txt
@@ -7,6 +7,7 @@ E: 17:pprint: Expected mapping for format string, not Tuple
 E: 18:pprint: Expected mapping for format string, not List
 E: 19:pprint: Unsupported format character 'z' (0x7a) at index 2
 E: 20:pprint: Format string ends in middle of conversion specifier
+E: 21:pprint: Unsupported format character 'a' (0x61) at index 12
 W: 15:pprint: Unused key 'PARG_3' in format string dictionary
 W: 16:pprint: Format string dictionary key should be a string, not 2
 
diff --git a/test/messages/func_e13xx_py30.txt b/test/messages/func_e13xx_py30.txt
new file mode 100644
index 0000000..7ac9fb1
--- /dev/null
+++ b/test/messages/func_e13xx_py30.txt
@@ -0,0 +1,11 @@
+E: 11:pprint: Not enough arguments for format string
+E: 12:pprint: Too many arguments for format string
+E: 13:pprint: Mixing named and unnamed conversion specifiers in format string
+E: 14:pprint: Missing key 'PARG_2' in format string dictionary
+E: 16:pprint: Missing key 'PARG_2' in format string dictionary
+E: 17:pprint: Expected mapping for format string, not Tuple
+E: 18:pprint: Expected mapping for format string, not List
+E: 19:pprint: Unsupported format character 'z' (0x7a) at index 2
+E: 20:pprint: Format string ends in middle of conversion specifier
+W: 15:pprint: Unused key 'PARG_3' in format string dictionary
+W: 16:pprint: Format string dictionary key should be a string, not 2
\ No newline at end of file