From afcaaafbe59c0c24c41ec481a0b0b5cd913fa10f Mon Sep 17 00:00:00 2001
From: Chris Lane <chris@chris-allen-lane.com>
Date: Sun, 25 May 2014 21:55:25 -0400
Subject: [PATCH] Improved filesystem efficiency

Previously, `sheets.print()` would query the filesystem every time it
was invoked. This was inelegant, because it is called multiple times
every time `cheat` is executed. Thus, unnecessary calls were being made
out to the filesystem.

Now the result of that function is being buffered into a module variable
when it is executed the first time, and served from there thereafter. I
broke the "functional" paradigm to a degree by doing this, but it wasn't
worth the complexity of implementing proper memoization (decorators,
etc) for such a trivial case.

Bumped the version number accordingly.
---
 bin/cheat       |  2 +-
 cheat/sheets.py | 15 +++++++++++++--
 setup.py        |  2 +-
 3 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/bin/cheat b/bin/cheat
index cc172d0..60bad56 100755
--- a/bin/cheat
+++ b/bin/cheat
@@ -38,7 +38,7 @@ from docopt import docopt
 
 if __name__ == '__main__':
     # parse the command-line options
-    options = docopt(__doc__, version='cheat 2.0.3')
+    options = docopt(__doc__, version='cheat 2.0.4')
 
     # list directories
     if options['--directories']:
diff --git a/cheat/sheets.py b/cheat/sheets.py
index c4da657..10dbfaf 100644
--- a/cheat/sheets.py
+++ b/cheat/sheets.py
@@ -2,6 +2,12 @@ from cheat import cheatsheets
 from cheat.utils import *
 import os
 
+# @kludge: it breaks the functional paradigm to a degree, but declaring this
+# var here (versus within get()) gives us a "poor man's" memoization on the
+# call to get(). This, in turn, spares us from having to call out to the
+# filesystem more than once.
+cheats = {}
+
 
 def default_path():
     """ Returns the default cheatsheet path """
@@ -35,10 +41,15 @@ def default_path():
     return default_sheets_dir
 
 
-# @todo: memoize result
 def get():
     """ Assembles a dictionary of cheatsheets as name => file-path """
-    cheats = {}
+
+    # if we've already reached out to the filesystem, just return the result
+    # from memory
+    if cheats:
+      return cheats
+
+    # otherwise, scan the filesystem
     for cheat_dir in reversed(paths()):
         cheats.update(
             dict([
diff --git a/setup.py b/setup.py
index 711969e..ef8eb69 100644
--- a/setup.py
+++ b/setup.py
@@ -12,7 +12,7 @@ if os.name == 'nt':
 
 setup(
     name         = 'cheat',
-    version      = '2.0.3',
+    version      = '2.0.4',
     author       = 'Chris Lane',
     author_email = 'chris@chris-allen-lane.com',
     license      = 'GPL3',