Script by Tim Peters to discover illegal append() calls.

Tools/scripts/checkappend.py

+#! /usr/bin/env python
+
+# Released to the public domain, by Tim Peters, 28 February 2000.
+
+"""checkappend.py -- search for multi-argument .append() calls.
+
+Usage:  specify one or more file or directory paths:
+    checkappend [-v] file_or_dir [file_or_dir] ...
+
+Each file_or_dir is checked for multi-argument .append() calls.  When
+a directory, all .py files in the directory, and recursively in its
+subdirectories, are checked.
+
+Use -v for status msgs.  Use -vv for more status msgs.
+
+In the absence of -v, the only output is pairs of the form
+
+    filename(linenumber):
+    line containing the suspicious append
+
+Note that this finds multi-argument append calls regardless of whether
+they're attached to list objects.  If a module defines a class with an
+append method that takes more than one argument, calls to that method
+will be listed.
+
+Note that this will not find multi-argument list.append calls made via a
+bound method object.  For example, this is not caught:
+
+    somelist = []
+    push = somelist.append
+    push(1, 2, 3)
+"""
+
+__version__ = 1, 0, 0
+
+import os
+import sys
+import string
+import getopt
+import tokenize
+
+verbose = 0
+
+def errprint(*args):
+    msg = string.join(args)
+    sys.stderr.write(msg)
+    sys.stderr.write("\n")
+
+def main():
+    args = sys.argv[1:]
+    global verbose
+    try:
+        opts, args = getopt.getopt(sys.argv[1:], "v")
+    except getopt.error, msg:
+        errprint(msg + "\n\n" + __doc__)
+        return
+    for opt, optarg in opts:
+        if opt == '-v':
+            verbose = verbose + 1
+    if not args:
+        errprint(__doc__)
+        return
+    for arg in args:
+        check(arg)
+
+def check(file):
+    if os.path.isdir(file) and not os.path.islink(file):
+        if verbose:
+            print "%s: listing directory" % `file`
+        names = os.listdir(file)
+        for name in names:
+            fullname = os.path.join(file, name)
+            if ((os.path.isdir(fullname) and
+                 not os.path.islink(fullname))
+                or os.path.normcase(name[-3:]) == ".py"):
+                check(fullname)
+        return
+
+    try:
+        f = open(file)
+    except IOError, msg:
+        errprint("%s: I/O Error: %s" % (`file`, str(msg)))
+        return
+
+    if verbose > 1:
+        print "checking", `file`, "..."
+
+    ok = AppendChecker(file, f).run()
+    if verbose and ok:
+        print "%s: Clean bill of health." % `file`
+
+[FIND_DOT,
+ FIND_APPEND,
+ FIND_LPAREN,
+ FIND_COMMA,
+ FIND_STMT]   = range(5)
+
+class AppendChecker:
+    def __init__(self, fname, file):
+        self.fname = fname
+        self.file = file
+        self.state = FIND_DOT
+        self.nerrors = 0
+
+    def run(self):
+        try:
+            tokenize.tokenize(self.file.readline, self.tokeneater)
+        except tokenize.TokenError, msg:
+            errprint("%s: Token Error: %s" % (`self.fname`, str(msg)))
+            self.nerrors = self.nerrors + 1
+        return self.nerrors == 0
+
+    def tokeneater(self, type, token, start, end, line,
+                NEWLINE=tokenize.NEWLINE,
+                JUNK=(tokenize.COMMENT, tokenize.NL),
+                OP=tokenize.OP,
+                NAME=tokenize.NAME):
+
+        state = self.state
+
+        if type in JUNK:
+            pass
+
+        elif state is FIND_DOT:
+            if type is OP and token == ".":
+                state = FIND_APPEND
+
+        elif state is FIND_APPEND:
+            if type is NAME and token == "append":
+                self.line = line
+                self.lineno = start[0]
+                state = FIND_LPAREN
+            else:
+                state = FIND_DOT
+
+        elif state is FIND_LPAREN:
+            if type is OP and token == "(":
+                self.level = 1
+                state = FIND_COMMA
+            else:
+                state = FIND_DOT
+
+        elif state is FIND_COMMA:
+            if type is OP:
+                if token in ("(", "{", "["):
+                    self.level = self.level + 1
+                elif token in (")", "}", "]"):
+                    self.level = self.level - 1
+                    if self.level == 0:
+                        state = FIND_DOT
+                elif token == "," and self.level == 1:
+                    self.nerrors = self.nerrors + 1
+                    print "%s(%d):\n%s" % (self.fname, self.lineno,
+                                           self.line)
+                    # don't gripe about this stmt again
+                    state = FIND_STMT
+
+        elif state is FIND_STMT:
+            if type is NEWLINE:
+                state = FIND_DOT
+
+        else:
+            raise SystemError("unknown internal state '%s'" % `state`)
+
+        self.state = state
+
+if __name__ == '__main__':
+    main()