make a bunch of functions pure

bin/autojump

@@ -21,7 +21,6 @@
 
 from __future__ import print_function
 
-from collections import namedtuple
 from functools import partial
 from itertools import chain
 # FIXME(ting|2013-12-17): fix imports for Python 3 compatability
@@ -37,11 +36,15 @@ import sys
 
 from argparse import ArgumentParser
 
+from data import dictify
+from data import entriefy
+from data import Entry
 from data import load
 from data import save
 from utils import decode
 from utils import encode_local
 from utils import first
+from utils import get_pwd
 from utils import has_uppercase
 from utils import is_osx
 from utils import print_entry
@@ -49,7 +52,6 @@ from utils import second
 from utils import take
 
 VERSION = 'release-v21.8.0'
-Entry = namedtuple('Entry', ['path', 'weight'])
 
 
 def set_defaults():
@@ -123,7 +125,7 @@ def parse_arguments():
     return parser.parse_args()
 
 
-def add_path(config, path, increment=10):
+def add_path(data, path, increment=10):
     """
     Add a new path or increment an existing one.
 
@@ -132,28 +134,21 @@ def add_path(config, path, increment=10):
     """
     path = decode(path).rstrip(os.sep)
     if path == os.path.expanduser('~'):
-        return path, 0
-
-    data = load(config)
+        return data, Entry(path, 0)
 
     if path in data:
         data[path] = sqrt((data[path]**2) + (increment**2))
     else:
         data[path] = increment
 
-    save(config, data)
-    return path, data[path]
+    return data, Entry(path, data[path])
 
 
-def decrease_path(config, path, increment=15):
+def decrease_path(data, path, increment=15):
     """Decrease weight of existing path."""
     path = decode(path).rstrip(os.sep)
-    data = load(config)
-
     data[path] = max(0, data[path]-increment)
-
-    save(config, data)
-    return path, data[path]
+    return data, Entry(path, data[path])
 
 
 def detect_smartcase(needles):
@@ -164,12 +159,16 @@ def detect_smartcase(needles):
     return not any(imap(has_uppercase, needles))
 
 
-def find_matches(config, needles):
+def find_matches(entries, needles):
     """Return an iterator to matching entries."""
-    entriefy = lambda tup: Entry(*tup)
-    not_cwd = lambda entry: entry.path != os.getcwdu()
+    try:
+        not_cwd = lambda entry: entry.path != os.getcwdu()
+    except OSError:
+        # tautology if current working directory no longer exists
+        not_cwd = lambda x: True
+
     data = sorted(
-            ifilter(not_cwd, imap(entriefy, load(config).iteritems())),
+            ifilter(not_cwd, entries),
             key=attrgetter('weight'),
             reverse=True)
 
@@ -233,20 +232,15 @@ def match_fuzzy(needles, haystack, ignore_case=False):
     return []
 
 
-def purge_missing_paths(config):
-    """Remove non-existent paths."""
-    exists = lambda x: os.path.exists(x[0])
-    old_data = load(config)
-    new_data = dict(ifilter(exists, old_data.iteritems()))
-    save(config, new_data)
-    return len(old_data) - len(new_data)
-
+def purge_missing_paths(entries):
+    """Remove non-existent paths from a list of entries."""
+    exists = lambda entry: os.path.exists(entry.path)
+    return ifilter(exists, entries)
 
-def print_stats(config):
-    data = load(config)
 
+def print_stats(data, data_path):
     for path, weight in sorted(data.iteritems(), key=itemgetter(1)):
-        print_entry(path, weight)
+        print_entry(Entry(path, weight))
 
     print("________________________________________\n")
     print("%d:\t total weight" % sum(data.itervalues()))
@@ -257,7 +251,7 @@ def print_stats(config):
     except OSError:
         pass
 
-    print("\ndata:\t %s" % config['data_path'])
+    print("\ndata:\t %s" % data_path)
 
 
 def main():
@@ -265,29 +259,28 @@ def main():
     args = parse_arguments()
 
     if args.add:
-        add_path(config, args.add)
+        save(config, first(add_path(load(config), args.add)))
     # elif args.complete:
         # config['match_cnt'] = 9
         # config['ignore_case'] = True
     elif args.decrease:
-        try:
-            print_entry(decrease_path(config, os.getcwdu(), args.decrease))
-        except OSError:
-            print("Current directory no longer exists.", file=sys.stderr)
-            return 1
+        data, entry = decrease_path(load(config), get_pwd(), args.decrease)
+        save(config, data)
+        print_entry(entry)
     elif args.increase:
-        try:
-            print_entry(add_path(config, os.getcwdu(), args.increase))
-        except OSError:
-            print("Current directory no longer exists.", file=sys.stderr)
-            return 1
+        data, entry = add_path(load(config), get_pwd(), args.decrease)
+        save(config, data)
+        print_entry(entry)
     elif args.purge:
-        print("Purged %d entries." % purge_missing_paths(config))
+        old_data = load(config)
+        new_data = dictify(purge_missing_paths(entriefy(old_data)))
+        save(config, new_data)
+        print("Purged %d entries." % (len(old_data)-len(new_data)))
     elif args.stat:
-        print_stats(config)
+        print_stats(load(config), config['data_path'])
     else:
         # default behavior, no optional arguments
-        result = first(find_matches(load(config).iteritems(), args.directory))
+        result = first(find_matches(entriefy(load(config)), args.directory))
 
         if result:
             print(encode_local(result.path))

bin/data.py

@@ -3,6 +3,7 @@
 from __future__ import print_function
 
 from codecs import open
+from collections import namedtuple
 from itertools import ifilter
 from itertools import imap
 from operator import itemgetter
@@ -17,9 +18,29 @@ from utils import move_file
 
 
 BACKUP_THRESHOLD = 24 * 60 * 60
+Entry = namedtuple('Entry', ['path', 'weight'])
+
+
+def dictify(entries):
+    """
+    Converts a list of entries into a dictionary where
+        key = path
+        value = weight
+    """
+    result = {}
+    for entry in entries:
+        result[entry.path] = entry.weight
+    return result
+
+
+def entriefy(data):
+    """Converts a dictionary into an iterator of entries."""
+    convert = lambda tup: Entry(*tup)
+    return imap(convert, data.iteritems())
 
 
 def load(config):
+    """Returns a dictonary (key=path, value=weight) loaded from data file."""
     xdg_aj_home = os.path.join(
             os.path.expanduser('~'),
             '.local',
@@ -30,19 +51,20 @@ def load(config):
         migrate_osx_xdg_data(config)
 
     if os.path.exists(config['data_path']):
+        # example: u'10.0\t/home/user\n' -> ['10.0', u'/home/user']
+        parse = lambda line: line.strip().split('\t')
+
+        correct_length = lambda x: len(x) == 2
+
+        # example: ['10.0', u'/home/user'] -> (u'/home/user', 10.0)
+        tupleize = lambda x: (x[1], float(x[0]))
+
         try:
             with open(config['data_path'], 'r', encoding='utf-8', errors='replace') as f:
-                lines = f.readlines()
+                return dict(imap(tupleize, ifilter(correct_length, imap(parse, f))))
         except (IOError, EOFError):
             return load_backup(config)
 
-        # example: u'10.0\t/home/user\n' -> ['10.0', u'/home/user']
-        parse = lambda x: x.strip().split('\t')
-        # example: ['10.0', u'/home/user'] -> (u'/home/user', 10.0)
-        convert = lambda x: (x[1], float(x[0]))
-        correct_length = lambda x: len(x) == 2
-
-        return dict(imap(convert, ifilter(correct_length, imap(parse, lines))))
     return {}
 
 

bin/utils.py

@@ -51,6 +51,14 @@ def first(xs):
         return None
 
 
+def get_pwd():
+    try:
+        return os.getcwdu()
+    except OSError:
+        print("Current directory no longer exists.", file=sys.stderr)
+        sys.exit(1)
+
+
 def has_uppercase(string):
     return any(unicodedata.category(c) == 'Lu' for c in unicode(string))
 
@@ -84,8 +92,8 @@ def move_file(src, dst):
     shutil.move(src, dst)
 
 
-def print_entry(path, weight):
-    print(encode_local("%.1f:\t%s" % (weight, path)))
+def print_entry(entry):
+    print(encode_local("%.1f:\t%s" % (entry.weight, entry.path)))
 
 
 def second(xs):