Py26 does not support implicit format spec numbering

As FichteFoll rightly pointed outin #1840, python 2.6 did *not* support
implicit format spec numbering for positional arguments.
This commit brings the code back in line with our promise that it is
compatible with python 2.6.

I used the following patterns to grep for occurences:
  - '"\{\}"'
  - '"\{:.*\}"'
  - "'\{\}'"
  - "'\{:.*\}'"

5 files changed, 26 insertions, 19 deletions

diff --git a/ranger/config/commands.py b/ranger/config/commands.py
index 5defa677..0171197a 100755
--- a/ranger/config/commands.py
+++ b/ranger/config/commands.py
@@ -1704,7 +1704,7 @@ class filter_stack(Command):
             return
         else:
             self.fm.notify(
-                "Unknown subcommand: {}".format(subcommand),
+                "Unknown subcommand: {sub}".format(sub=subcommand),
                 bad=True
             )
             return
diff --git a/ranger/core/actions.py b/ranger/core/actions.py
index c3d7de86..020f0a4b 100644
--- a/ranger/core/actions.py
+++ b/ranger/core/actions.py
@@ -242,14 +242,14 @@ class Actions(  # pylint: disable=too-many-instance-attributes,too-many-public-m
 
         if cmd.resolve_macros and _MacroTemplate.delimiter in cmd.line:
             def any_macro(i, char):
-                return ('any{:d}'.format(i), key_to_string(char))
+                return ('any{0:d}'.format(i), key_to_string(char))
 
             def anypath_macro(i, char):
                 try:
                     val = self.fm.bookmarks[key_to_string(char)]
                 except KeyError:
                     val = MACRO_FAIL
-                return ('any_path{:d}'.format(i), val)
+                return ('any_path{0:d}'.format(i), val)
 
             macros = dict(f(i, char) for f in (any_macro, anypath_macro)
                           for i, char in enumerate(wildcards if wildcards
@@ -1609,7 +1609,7 @@ class Actions(  # pylint: disable=too-many-instance-attributes,too-many-public-m
         # COMPAT: old command.py use fm.delete() without arguments
         if files is None:
             files = (fobj.path for fobj in self.thistab.get_selection())
-        self.notify("Deleting {}!".format(", ".join(files)))
+        self.notify("Deleting {fls}!".format(fls=", ".join(files)))
         files = [os.path.abspath(path) for path in files]
         for path in files:
             # Untag the deleted files.
diff --git a/ranger/core/filter_stack.py b/ranger/core/filter_stack.py
index bd63f2fe..895f5e58 100644
--- a/ranger/core/filter_stack.py
+++ b/ranger/core/filter_stack.py
@@ -55,7 +55,7 @@ class NameFilter(BaseFilter):
         return self.regex.search(fobj.relative_path)
 
     def __str__(self):
-        return "<Filter: name =~ /{}/>".format(self.pattern)
+        return "<Filter: name =~ /{pat}/>".format(pat=self.pattern)
 
 
 @stack_filter("mime")
@@ -71,7 +71,7 @@ class MimeFilter(BaseFilter):
         return self.regex.search(mimetype)
 
     def __str__(self):
-        return "<Filter: mimetype =~ /{}/>".format(self.pattern)
+        return "<Filter: mimetype =~ /{pat}/>".format(pat=self.pattern)
 
 
 @stack_filter("hash")
@@ -97,7 +97,7 @@ class HashFilter(BaseFilter, FileManagerAware):
         return True
 
     def __str__(self):
-        return "<Filter: hash {}>".format(self.filepath)
+        return "<Filter: hash {fp}>".format(fp=self.filepath)
 
 
 def group_by_hash(fsobjects):
@@ -192,7 +192,7 @@ class TypeFilter(BaseFilter):
         return self.type_to_function[self.filetype](fobj)
 
     def __str__(self):
-        return "<Filter: type == '{}'>".format(self.filetype)
+        return "<Filter: type == '{ft}'>".format(ft=self.filetype)
 
 
 @filter_combinator("or")
@@ -216,7 +216,9 @@ class OrFilter(BaseFilter):
         )
 
     def __str__(self):
-        return "<Filter: {}>".format(" or ".join(map(str, self.subfilters)))
+        return "<Filter: {comp}>".format(
+            comp=" or ".join(map(str, self.subfilters)))
+
 
     def decompose(self):
         return self.subfilters
@@ -236,7 +238,8 @@ class AndFilter(BaseFilter):
         return accept_file(fobj, self.subfilters)
 
     def __str__(self):
-        return "<Filter: {}>".format(" and ".join(map(str, self.subfilters)))
+        return "<Filter: {comp}>".format(
+            comp=" and ".join(map(str, self.subfilters)))
 
     def decompose(self):
         return self.subfilters
@@ -252,7 +255,7 @@ class NotFilter(BaseFilter):
         return not self.subfilter(fobj)
 
     def __str__(self):
-        return "<Filter: not {}>".format(str(self.subfilter))
+        return "<Filter: not {exp}>".format(exp=str(self.subfilter))
 
     def decompose(self):
         return [self.subfilter]
diff --git a/ranger/core/main.py b/ranger/core/main.py
index 5f7abaca..b16b6318 100644
--- a/ranger/core/main.py
+++ b/ranger/core/main.py
@@ -347,7 +347,7 @@ def parse_arguments():
             except Exception as ex:  # pylint: disable=broad-except
                 sys.stderr.write(
                     "Error during the temporary cache directory cleanup:\n"
-                    "{}\n".format(ex)
+                    "{ex}\n".format(ex=ex)
                 )
 
     else:
diff --git a/ranger/ext/img_display.py b/ranger/ext/img_display.py
index ffaa4c07..70983bc7 100644
--- a/ranger/ext/img_display.py
+++ b/ranger/ext/img_display.py
@@ -233,7 +233,7 @@ class W3MImageDisplayer(ImageDisplayer, FileManagerAware):
         # max_height_pixels = (max_height - 1) * fonth - 2
 
         # get image size
-        cmd = "5;{}\n".format(path)
+        cmd = "5;{path}\n".format(path=path)
 
         self.process.stdin.write(cmd)
         self.process.stdin.flush()
@@ -590,7 +590,7 @@ class KittyImageDisplayer(ImageDisplayer, FileManagerAware):
             self.stream = True
         else:
             raise ImgDisplayUnsupportedException(
-                'kitty replied an unexpected response: {}'.format(resp))
+                'kitty replied an unexpected response: {r}'.format(r=resp))
 
         # get the image manipulation backend
         try:
@@ -616,7 +616,8 @@ class KittyImageDisplayer(ImageDisplayer, FileManagerAware):
         # a is the display command, with T going for immediate output
         # i is the id entifier for the image
         cmds = {'a': 'T', 'i': self.image_id}
-        # sys.stderr.write('{}-{}@{}x{}\t'.format(start_x, start_y, width, height))
+        # sys.stderr.write('{0}-{1}@{2}x{3}\t'.format(
+        #     start_x, start_y, width, height))
 
         # finish initialization if it is the first call
         if self.needs_late_init:
@@ -673,12 +674,13 @@ class KittyImageDisplayer(ImageDisplayer, FileManagerAware):
         if b'OK' in resp:
             return
         else:
-            raise ImageDisplayError('kitty replied "{}"'.format(resp))
+            raise ImageDisplayError('kitty replied "{r}"'.format(r=resp))
 
     def clear(self, start_x, start_y, width, height):
         # let's assume that every time ranger call this
         # it actually wants just to remove the previous image
-        # TODO: implement this using the actual x, y, since the protocol supports it
+        # TODO: implement this using the actual x, y, since the protocol
+        #       supports it
         cmds = {'a': 'd', 'i': self.image_id}
         for cmd_str in self._format_cmd_str(cmds):
             self.stdbout.write(cmd_str)
@@ -690,7 +692,8 @@ class KittyImageDisplayer(ImageDisplayer, FileManagerAware):
         self.fm.ui.win.refresh()
 
     def _format_cmd_str(self, cmd, payload=None, max_slice_len=2048):
-        central_blk = ','.join(["{}={}".format(k, v) for k, v in cmd.items()]).encode('ascii')
+        central_blk = ','.join(["{k}={v}".format(k=k, v=v)
+                                for k, v in cmd.items()]).encode('ascii')
         if payload is not None:
             # we add the m key to signal a multiframe communication
             # appending the end (m=0) key to a single message has no effect
@@ -706,7 +709,8 @@ class KittyImageDisplayer(ImageDisplayer, FileManagerAware):
             yield self.protocol_start + central_blk + b';' + self.protocol_end
 
     def quit(self):
-        # clear all remaining images, then check if all files went through or are orphaned
+        # clear all remaining images, then check if all files went through or
+        # are orphaned
         while self.image_id >= 1:
             self.clear(0, 0, 0, 0)
         # for k in self.temp_paths: