py3k: 2to3's "idiom" filter

This is, I guess, a few things the Python devs were just fed up with.

* "while 1" is now "while True"
* Types are compared with isinstance instead of ==
* Sort a list in one go with sorted()

My own twist is to also replace type('') with str, type(()) with tuple,
type([]) with list, type(1) with int, and type(5000.0) with float.

PIL/ArgImagePlugin.py

@@ -458,7 +458,7 @@ class ArgImageFile(ImageFile.ImageFile):
 
         self.fp = self.arg.fp
 
-        while 1:
+        while True:
 
             #
             # process chunks

PIL/BdfFontFile.py

@@ -43,7 +43,7 @@ bdf_spacing = {
 def bdf_char(f):
 
     # skip to STARTCHAR
-    while 1:
+    while True:
         s = f.readline()
         if not s:
             return None
@@ -53,7 +53,7 @@ def bdf_char(f):
 
     # load symbol properties
     props = {}
-    while 1:
+    while True:
         s = f.readline()
         if not s or s[:6] == "BITMAP":
             break
@@ -62,7 +62,7 @@ def bdf_char(f):
 
     # load bitmap
     bitmap = []
-    while 1:
+    while True:
         s = f.readline()
         if not s or s[:7] == "ENDCHAR":
             break
@@ -98,7 +98,7 @@ class BdfFontFile(FontFile.FontFile):
         props = {}
         comments = []
 
-        while 1:
+        while True:
             s = fp.readline()
             if not s or s[:13] == "ENDPROPERTIES":
                 break
@@ -123,7 +123,7 @@ class BdfFontFile(FontFile.FontFile):
         #       print "#", i
 
         font = []
-        while 1:
+        while True:
             c = bdf_char(fp)
             if not c:
                 break

PIL/ContainerIO.py

@@ -92,7 +92,7 @@ class ContainerIO:
 
     def readline(self):
         s = ""
-        while 1:
+        while True:
             c = self.read(1)
             if not c:
                 break
@@ -108,7 +108,7 @@ class ContainerIO:
 
     def readlines(self):
         l = []
-        while 1:
+        while True:
             s = self.readline()
             if not s:
                 break

PIL/EpsImagePlugin.py

@@ -261,7 +261,7 @@ class EpsImageFile(ImageFile.ImageFile):
                     id = id[1:-1]
 
                 # Scan forward to the actual image data
-                while 1:
+                while True:
                     s = fp.readline()
                     if not s:
                         break

PIL/GdImageFile.py

@@ -78,7 +78,7 @@ def open(fp, mode = "r"):
     if mode != "r":
         raise ValueError("bad mode")
 
-    if type(fp) == type(""):
+    if isinstance(fp, str):
         filename = fp
         fp = builtins.open(fp, "rb")
     else:

PIL/GifImagePlugin.py

@@ -125,7 +125,7 @@ class GifImageFile(ImageFile.ImageFile):
 
         self.palette = self.global_palette
 
-        while 1:
+        while True:
 
             s = self.fp.read(1)
             if not s or s == ";":

PIL/ImImagePlugin.py

@@ -125,7 +125,7 @@ class ImImageFile(ImageFile.ImageFile):
 
         self.rawmode = "L"
 
-        while 1:
+        while True:
 
             s = self.fp.read(1)
 

PIL/Image.py

@@ -218,8 +218,7 @@ def _conv_type_shape(im):
         return shape+(extra,), typ
 
 
-MODES = list(_MODEINFO.keys())
+MODES = sorted(_MODEINFO.keys())
-MODES.sort()
 
 # raw modes that may be memory mapped.  NOTE: if you change this, you
 # may have to modify the stride calculation in map.c too!
@@ -532,7 +531,7 @@ class Image:
         bufsize = max(65536, self.size[0] * 4) # see RawEncode.c
 
         data = []
-        while 1:
+        while True:
             l, s, d = e.encode(bufsize)
             data.append(d)
             if s:

PIL/ImageCms.py

@@ -124,7 +124,7 @@ FLAGS = {
 
 _MAX_FLAG = 0
 for flag in FLAGS.values():
-    if isinstance(flag, type(0)):
+    if isinstance(flag, int):
         _MAX_FLAG = _MAX_FLAG | flag
 
 # --------------------------------------------------------------------.
@@ -290,10 +290,10 @@ def profileToProfile(im, inputProfile, outputProfile, renderingIntent=INTENT_PER
     if outputMode is None:
         outputMode = im.mode
 
-    if type(renderingIntent) != type(1) or not (0 <= renderingIntent <=3):
+    if not isinstance(renderingIntent, int) or not (0 <= renderingIntent <=3):
         raise PyCMSError("renderingIntent must be an integer between 0 and 3")
 
-    if type(flags) != type(1) or not (0 <= flags <= _MAX_FLAG):
+    if not isinstance(flags, int) or not (0 <= flags <= _MAX_FLAG):
         raise PyCMSError("flags must be an integer between 0 and %s" + _MAX_FLAG)
 
     try:
@@ -398,10 +398,10 @@ def buildTransform(inputProfile, outputProfile, inMode, outMode, renderingIntent
 
     """
 
-    if type(renderingIntent) != type(1) or not (0 <= renderingIntent <=3):
+    if not isinstance(renderingIntent, int) or not (0 <= renderingIntent <=3):
         raise PyCMSError("renderingIntent must be an integer between 0 and 3")
 
-    if type(flags) != type(1) or not (0 <= flags <= _MAX_FLAG):
+    if not isinstance(flags, int) or not (0 <= flags <= _MAX_FLAG):
         raise PyCMSError("flags must be an integer between 0 and %s" + _MAX_FLAG)
 
     try:
@@ -489,10 +489,10 @@ def buildProofTransform(inputProfile, outputProfile, proofProfile, inMode, outMo
 
     """
 
-    if type(renderingIntent) != type(1) or not (0 <= renderingIntent <=3):
+    if not isinstance(renderingIntent, int) or not (0 <= renderingIntent <=3):
         raise PyCMSError("renderingIntent must be an integer between 0 and 3")
 
-    if type(flags) != type(1) or not (0 <= flags <= _MAX_FLAG):
+    if not isinstance(flags, int) or not (0 <= flags <= _MAX_FLAG):
         raise PyCMSError("flags must be an integer between 0 and %s" + _MAX_FLAG)
 
     try:
@@ -597,9 +597,9 @@ def createProfile(colorSpace, colorTemp=-1):
         raise PyCMSError("Color space not supported for on-the-fly profile creation (%s)" % colorSpace)
 
     if colorSpace == "LAB":
-        if type(colorTemp) == type(5000.0):
+        if isinstance(colorTemp, float):
             colorTemp = int(colorTemp + 0.5)
-        if type (colorTemp) != type (5000):
+        if not isinstance(colorTemp, int):
             raise PyCMSError("Color temperature must be a positive integer, \"%s\" not valid" % colorTemp)
 
     try:

PIL/ImageColor.py

@@ -41,7 +41,7 @@ def getrgb(color):
             rgb = None
     # found color in cache
     if rgb:
-        if isinstance(rgb, type(())):
+        if isinstance(rgb, tuple):
             return rgb
         colormap[color] = rgb = getrgb(rgb)
         return rgb

PIL/ImageFile.py

@@ -195,7 +195,7 @@ class ImageFile(Image.Image):
                     continue
                 b = prefix
                 t = len(b)
-                while 1:
+                while True:
                     s = read(self.decodermaxblock)
                     if not s:
                         self.tile = []
@@ -315,7 +315,7 @@ class _ParserFile:
     def readline(self):
         # FIXME: this is slow!
         s = ""
-        while 1:
+        while True:
             c = self.read(1)
             if not c:
                 break
@@ -483,7 +483,7 @@ def _save(im, fp, tile):
             if o > 0:
                 fp.seek(o, 0)
             e.setimage(im.im, b)
-            while 1:
+            while True:
                 l, s, d = e.encode(bufsize)
                 fp.write(d)
                 if s:

PIL/ImageMath.py

@@ -28,7 +28,7 @@ except ImportError:
 VERBOSE = 0
 
 def _isconstant(v):
-    return isinstance(v, type(0)) or isinstance(v, type(0.0))
+    return isinstance(v, int) or isinstance(v, float)
 
 class _Operand:
     # wraps an image operand, providing standard operators

PIL/ImageOps.py

@@ -33,7 +33,7 @@ from functools import reduce
 # helpers
 
 def _border(border):
-    if type(border) is type(()):
+    if isinstance(border, tuple):
         if len(border) == 2:
             left, top = right, bottom = border
         elif len(border) == 4:
@@ -275,7 +275,7 @@ def fit(image, size, method=Image.NEAREST, bleed=0.0, centering=(0.5, 0.5)):
     # http://www.cazabon.com
 
     # ensure inputs are valid
-    if type(centering) != type([]):
+    if not isinstance(centering, list):
         centering = [centering[0], centering[1]]
 
     if centering[0] > 1.0 or centering[0] < 0.0:

PIL/ImagePalette.py

@@ -76,7 +76,7 @@ class ImagePalette:
         # (experimental) save palette to text file
         if self.rawmode:
             raise ValueError("palette contains raw palette data")
-        if type(fp) == type(""):
+        if isinstance(fp, str):
             fp = open(fp, "w")
         fp.write("# Palette\n")
         fp.write("# Mode: %s\n" % self.mode)

PIL/ImageStat.py

@@ -53,7 +53,7 @@ class Stat:
                 self.h = image_or_list.histogram()
         except AttributeError:
             self.h = image_or_list # assume it to be a histogram list
-        if type(self.h) != type([]):
+        if not isinstance(self.h, list):
             raise TypeError("first argument must be image or list")
         self.bands = list(range(len(self.h) // 256))
 

PIL/ImtImagePlugin.py

@@ -45,7 +45,7 @@ class ImtImageFile(ImageFile.ImageFile):
 
         xsize = ysize = 0
 
-        while 1:
+        while True:
 
             s = self.fp.read(1)
             if not s:

PIL/IptcImagePlugin.py

@@ -98,7 +98,7 @@ class IptcImageFile(ImageFile.ImageFile):
         if sz != size[0]:
             return 0
         y = 1
-        while 1:
+        while True:
             self.fp.seek(sz, 1)
             t, s = self.field()
             if t != (8, 10):
@@ -111,7 +111,7 @@ class IptcImageFile(ImageFile.ImageFile):
     def _open(self):
 
         # load descriptive fields
-        while 1:
+        while True:
             offset = self.fp.tell()
             tag, size = self.field()
             if not tag or tag == (8,10):
@@ -180,7 +180,7 @@ class IptcImageFile(ImageFile.ImageFile):
             # To simplify access to the extracted file,
             # prepend a PPM header
             o.write("P5\n%d %d\n255\n" % self.size)
-        while 1:
+        while True:
             type, size = self.field()
             if type != (8, 10):
                 break

PIL/JpegImagePlugin.py

@@ -287,7 +287,7 @@ class JpegImageFile(ImageFile.ImageFile):
         self.applist = []
         self.icclist = []
 
-        while 1:
+        while True:
 
             s = s + self.fp.read(1)
 

PIL/OleFileIO.py

@@ -175,7 +175,7 @@ class _OleDirectoryEntry:
                 if right != -1: # 0xFFFFFFFFL:
                     # and then back to the left
                     sid = right
-                    while 1:
+                    while True:
                         left, right, child = sidlist[sid][4]
                         if left == -1: # 0xFFFFFFFFL:
                             break
@@ -183,7 +183,7 @@ class _OleDirectoryEntry:
                         sid = left
                 else:
                     # couldn't move right; move up instead
-                    while 1:
+                    while True:
                         ptr = stack[-1]
                         del stack[-1]
                         left, right, child = sidlist[ptr][4]
@@ -267,7 +267,7 @@ class OleFileIO:
     def open(self, filename):
         """Open an OLE2 file"""
 
-        if type(filename) == type(""):
+        if isinstance(filename, str):
             self.fp = open(filename, "rb")
         else:
             self.fp = filename
@@ -345,7 +345,7 @@ class OleFileIO:
 
         # create list of sid entries
         self.sidlist = []
-        while 1:
+        while True:
             entry = fp.read(128)
             if not entry:
                 break
@@ -525,8 +525,7 @@ if __name__ == "__main__":
                 if file[-1][0] == "\005":
                     print(file)
                     props = ole.getproperties(file)
-                    props = list(props.items())
+                    props = sorted(props.items())
-                    props.sort()
                     for k, v in props:
                         print("   ", k, v)
         except IOError as v:

PIL/PaletteFile.py

@@ -24,7 +24,7 @@ class PaletteFile:
 
         self.palette = [(i, i, i) for i in range(256)]
 
-        while 1:
+        while True:
 
             s = fp.readline()
 

PIL/PngImagePlugin.py

@@ -138,7 +138,7 @@ class ChunkStream:
 
         cids = []
 
-        while 1:
+        while True:
             cid, pos, len = self.read()
             if cid == endchunk:
                 break
@@ -323,7 +323,7 @@ class PngImageFile(ImageFile.ImageFile):
 
         self.png = PngStream(self.fp)
 
-        while 1:
+        while True:
 
             #
             # get next chunk

PIL/PpmImagePlugin.py

@@ -49,7 +49,7 @@ class PpmImageFile(ImageFile.ImageFile):
     format_description = "Pbmplus image"
 
     def _token(self, s = ""):
-        while 1: # read until next whitespace
+        while True: # read until next whitespace
             c = self.fp.read(1)
             if not c or c in string.whitespace:
                 break
@@ -71,8 +71,8 @@ class PpmImageFile(ImageFile.ImageFile):
             self.mode = rawmode = mode
 
         for ix in range(3):
-            while 1:
+            while True:
-                while 1:
+                while True:
                     s = self.fp.read(1)
                     if s not in string.whitespace:
                         break

PIL/TarIO.py

@@ -32,7 +32,7 @@ class TarIO(ContainerIO.ContainerIO):
 
         fh = open(tarfile, "rb")
 
-        while 1:
+        while True:
 
             s = fh.read(512)
             if len(s) != 512:

PIL/TiffImagePlugin.py

@@ -401,8 +401,7 @@ class ImageFileDirectory(collections.MutableMapping):
         fp.write(o16(len(self.tags)))
 
         # always write in ascending tag order
-        tags = list(self.tags.items())
+        tags = sorted(self.tags.items())
-        tags.sort()
 
         directory = []
         append = directory.append
@@ -425,7 +424,7 @@ class ImageFileDirectory(collections.MutableMapping):
             elif typ == 7:
                 # untyped data
                 data = value = "".join(value)
-            elif type(value[0]) is type(""):
+            elif isinstance(value[0], str):
                 # string data
                 typ = 2
                 data = value = "\0".join(value) + "\0"
@@ -737,10 +736,10 @@ SAVE_INFO = {
 
 def _cvt_res(value):
     # convert value to TIFF rational number -- (numerator, denominator)
-    if type(value) in (type([]), type(())):
+    if isinstance(value, collections.Sequence):
         assert(len(value) % 2 == 0)
         return value
-    if type(value) == type(1):
+    if isinstance(value, int):
         return (value, 1)
     value = float(value)
     return (int(value * 65536), 65536)

PIL/XVThumbImagePlugin.py

@@ -47,7 +47,7 @@ class XVThumbImageFile(ImageFile.ImageFile):
         self.fp.readline()
 
         # skip info comments
-        while 1:
+        while True:
             s = self.fp.readline()
             if not s:
                 raise SyntaxError("Unexpected EOF reading XV thumbnail file")

PIL/XpmImagePlugin.py

@@ -42,7 +42,7 @@ class XpmImageFile(ImageFile.ImageFile):
             raise SyntaxError("not an XPM file")
 
         # skip forward to next string
-        while 1:
+        while True:
             s = self.fp.readline()
             if not s:
                 raise SyntaxError("broken XPM file")

Sane/sane.py

@@ -55,7 +55,7 @@ class Option:
         def f(x):
             if x=='-': return '_'
             else: return x
-        if type(self.name)!=type(''): self.py_name=str(self.name)
+        if not isinstance(self.name, str): self.py_name=str(self.name)
         else: self.py_name=''.join(map(f, self.name))
 
     def is_active(self):
@@ -174,7 +174,7 @@ class SaneDev:
             raise AttributeError('Inactive option: '+key)
         if not _sane.OPTION_IS_SETTABLE(opt.cap):
             raise AttributeError("Option can't be set by software: "+key)
-        if type(value) == int and opt.type == TYPE_FIXED:
+        if isinstance(value, int) and opt.type == TYPE_FIXED:
             # avoid annoying errors of backend if int is given instead float:
             value = float(value)
         self.last_opt = dev.set_option(opt.index, value)

Scripts/explode.py

@@ -89,7 +89,7 @@ if html:
     html = open(file+".html", "w")
     html.write("<html>\n<body>\n")
 
-while 1:
+while True:
 
     if frames[ix]:
         im.save(outfile % ix)

Scripts/pilconvert.py

@@ -56,8 +56,7 @@ for o, a in opt:
 
     if o == "-f":
         Image.init()
-        id = Image.ID[:]
+        id = sorted(Image.ID)
-        id.sort()
         print("Supported formats (* indicates output format):")
         for i in id:
             if i in Image.SAVE:

Scripts/pildriver.py

@@ -485,7 +485,7 @@ class PILDriver:
             if self.verbose:
                 print("Stack: " + repr(self.stack))
             top = self.top()
-            if type(top) != type(""):
+            if not isinstance(top, str):
                 continue;
             funcname = "do_" + top
             if not hasattr(self, funcname):
@@ -510,7 +510,7 @@ if __name__ == '__main__':
         driver.execute(sys.argv[1:])
     else:
         print("PILDriver says hello.")
-        while 1:
+        while True:
             try:
                 line = raw_input('pildriver> ');
             except EOFError:

Scripts/pilfile.py

@@ -45,8 +45,7 @@ verbose = quiet = verify = 0
 for o, a in opt:
     if o == "-f":
         Image.init()
-        id = Image.ID[:]
+        id = sorted(Image.ID)
-        id.sort()
         print("Supported formats:")
         for i in id:
             print(i, end=' ')

Scripts/player.py

@@ -42,7 +42,7 @@ class AppletDisplay:
 class UI(Label):
 
     def __init__(self, master, im):
-        if type(im) == type([]):
+        if isinstance(im, list):
             # list of images
             self.im = im[1:]
             im = self.im[0]
@@ -71,7 +71,7 @@ class UI(Label):
 
     def next(self):
 
-        if type(self.im) == type([]):
+        if isinstance(self.im, list):
 
             try:
                 im = self.im[0]