├── README.markdown
└── objc_cover.py


/README.markdown:
--------------------------------------------------------------------------------
 1 | Say you have this Objective-C code:
 2 | 
 3 |     - (void)notUsed {
 4 |     	return;
 5 |     }
 6 | 
 7 |     - (void)actuallyUsed {
 8 |     	return;
 9 |     }
10 | 
11 |     // ...
12 |     
13 |     [self actuallyUsed];
14 | 
15 | Thanks to `/usr/bin/otool`, you can get clues about potentially unused methods, like this:
16 | 
17 |     $ python objc_cover.py /Users/nst/Desktop/iCalReport 
18 |     # the following methods may be unreferenced
19 |     -[MyClass notUsed]
20 | 
21 | The idea was [put first](http://lists.apple.com/archives/objc-language/2009/Oct/msg00085.html) by "Luke the Hiesterman" on the Apple Objective-C list.
22 | 


--------------------------------------------------------------------------------
/objc_cover.py:
--------------------------------------------------------------------------------
  1 | #!/usr/bin/python
  2 | 
  3 | __author__ = "Nicolas Seriot"
  4 | __date__ = "2010-03-01"
  5 | __license__ = "GPL"
  6 | 
  7 | import os
  8 | import re
  9 | import shutil
 10 | import sys
 11 | import tempfile
 12 | 
 13 | def verified_macho_path(args):
 14 |     if len(sys.argv) != 2:
 15 |         return None
 16 | 
 17 |     path = sys.argv[1]
 18 | 
 19 |     if not os.path.isfile(path):
 20 |         return None
 21 | 
 22 |     ## Apparently there is a bug in otool -- it doesn't seem to like executables
 23 |     ## with spaces in the names. If this is the case, make a copy and analyze that.
 24 |     if ' ' in os.path.basename(path):
 25 |         ## don't remove the spaces, that could lead to an empty string
 26 |         new_filename = path.replace(' ', '_')
 27 |         new_path = os.path.join(tempfile.mkdtemp(), new_filename)
 28 |         shutil.copy(path, new_path)
 29 |         path = new_path
 30 | 
 31 |     cmd = "/usr/bin/file -b %r" % path
 32 |     s = os.popen(cmd).read()
 33 | 
 34 |     if not s.startswith('Mach-O'):
 35 |         return None
 36 |     
 37 |     return path
 38 | 
 39 | def signature_cmp(m1, m2):
 40 |     cls1 = m1[2:].split(' ')[0]
 41 |     cls2 = m2[2:].split(' ')[0]
 42 |     
 43 |     result = cmp(cls1, cls2)
 44 | 
 45 |     if result == 0: # same class
 46 |         if m1.startswith('+') and m2.startswith('-'):
 47 |             return -1
 48 |         elif m1.startswith('-') and m2.startswith('+'):
 49 |             return +1
 50 |         else: # same sign
 51 |             return cmp(m1, m2)
 52 |     
 53 |     return result
 54 | 
 55 | def implemented_methods(path):
 56 |     """
 57 |     returns {'sel1':[sig1, sig2], 'sel2':[sig3]}
 58 |     """
 59 |     
 60 |     re_sig_sel_ios = re.compile("\s*imp 0x\w+ ([+|-]\[.+\s(.+)\])")
 61 |     re_sig_sel_mac = re.compile("\s*imp ([+|-]\[.+\s(.+)\])")
 62 |     
 63 |     impl = {} # sel -> clsmtd
 64 |     
 65 |     for line in os.popen("/usr/bin/otool -oV %s" % path).xreadlines():
 66 |         results = re_sig_sel_ios.findall(line)
 67 |         if not results:
 68 |             results = re_sig_sel_mac.findall(line)
 69 |         #print results
 70 |         
 71 |         if not results:
 72 |             continue
 73 |         (sig, sel) = results[0]
 74 |         
 75 |         if sel in impl:
 76 |             impl[sel].append(sig)
 77 |         else:
 78 |             impl[sel] = [sig]
 79 |     
 80 |     return impl
 81 | 
 82 | def referenced_selectors(path):
 83 |     
 84 |     re_sel = re.compile("__TEXT:__objc_methname:(.+)")
 85 |     
 86 |     refs = set()
 87 |     
 88 |     lines = os.popen("/usr/bin/otool -v -s __DATA __objc_selrefs %s" % path).readlines() # ios & mac
 89 | 
 90 |     for line in lines:
 91 |         results = re_sel.findall(line)
 92 |         if results:
 93 |             refs.add(results[0])
 94 |     
 95 |     return refs
 96 | 
 97 | def potentially_unreferenced_methods():
 98 |     implemented = implemented_methods(path)
 99 |     
100 |     if not implemented:
101 |         print "# can't find implemented methods"
102 |         sys.exit(1)
103 |     
104 |     referenced = referenced_selectors(path)
105 |     
106 |     l = []
107 |     
108 |     #print "-- implemented:", len(implemented)
109 |     #print "-- referenced:", len(referenced)
110 | 
111 |     for sel in implemented:
112 |         if sel not in referenced:
113 |             for method in implemented[sel]:
114 |                 l.append(method)
115 |                 
116 |     l.sort(signature_cmp)
117 |     
118 |     return l
119 | 
120 | if __name__ == "__main__":
121 |     
122 |     path = verified_macho_path(sys.argv)
123 |     if not path:
124 |         print "Usage: %s MACH_O_FILE" % sys.argv[0]
125 |         sys.exit(1)
126 |     
127 |     methods = potentially_unreferenced_methods()
128 |         
129 |     print "# the following methods may be unreferenced"
130 |     for m in methods:
131 |         print m
132 | 


--------------------------------------------------------------------------------