encoding: define an enum that specifies what normcase does to ASCII strings
authorSiddharth Agarwal <sid0@fb.com>
Wed, 01 Apr 2015 00:21:10 -0700
changeset 24593 f473a1fe5c7c
parent 24592 d7cf8102bf09
child 24594 609aa973c01d
encoding: define an enum that specifies what normcase does to ASCII strings For C code we don't want to pay the cost of calling into a Python function for the common case of ASCII filenames. However, while on most POSIX platforms we normalize filenames by lowercasing them, on Windows we uppercase them. We define an enum here indicating the direction that filenames should be normalized as. Some platforms (notably Cygwin) have more complicated normalization behavior -- we add a case for that too. In upcoming patches we'll also define a fallback function that is called if the string has non-ASCII bytes. This enum will be replicated in the C code to make foldmaps. There's unfortunately no nice way to avoid that -- we can't have encoding import parsers because of import cycles. One way might be to have parsers import encoding, but accessing Python modules from C code is just awkward. The name 'normcasespecs' was chosen to indicate that this is merely an integer that specifies a behavior, not a function. The name was pluralized since in upcoming patches we'll introduce 'normcasespec' which will be one of these values.
mercurial/encoding.py
--- a/mercurial/encoding.py	Thu Apr 02 16:51:00 2015 -0500
+++ b/mercurial/encoding.py	Wed Apr 01 00:21:10 2015 -0700
@@ -354,6 +354,19 @@
     except LookupError, k:
         raise error.Abort(k, hint="please check your locale settings")
 
+class normcasespecs(object):
+    '''what a platform's normcase does to ASCII strings
+
+    This is specified per platform, and should be consistent with what normcase
+    on that platform actually does.
+
+    lower: normcase lowercases ASCII strings
+    upper: normcase uppercases ASCII strings
+    other: the fallback function should always be called'''
+    lower = -1
+    upper = 1
+    other = 0
+
 _jsonmap = {}
 
 def jsonescape(s):