--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/Plugins/CheckerPlugins/Tabnanny/Tabnanny.py Mon Dec 28 16:03:33 2009 +0000
@@ -0,0 +1,403 @@
+# -*- coding: utf-8 -*-
+
+"""
+The Tab Nanny despises ambiguous indentation. She knows no mercy.
+
+tabnanny -- Detection of ambiguous indentation
+
+For the time being this module is intended to be called as a script.
+However it is possible to import it into an IDE and use the function
+check() described below.
+
+Warning: The API provided by this module is likely to change in future
+releases; such changes may not be backward compatible.
+
+This is a modified version to make the original tabnanny better suitable
+for being called from within the eric4 IDE.
+
+@exception ValueError The tokenize module is too old.
+"""
+
+# Released to the public domain, by Tim Peters, 15 April 1998.
+
+# XXX Note: this is now a standard library module.
+# XXX The API needs to undergo changes however; the current code is too
+# XXX script-like. This will be addressed later.
+
+#
+# This is a modified version to make the original tabnanny better suitable
+# for being called from within the eric4 IDE. The modifications are as
+# follows:
+#
+# - there is no main function anymore
+# - check function has been modified to only accept a filename and return
+# a tuple indicating status (1 = an error was found), the filename, the
+# linenumber and the error message (boolean, string, string, string). The
+# values are only valid, if the status equals 1.
+#
+# Mofifications copyright (c) 2003 Detlev Offenbach <detlev@die-offenbachs.de>
+#
+
+__version__ = "6_eric"
+
+import os
+import sys
+import tokenize
+import cStringIO
+
+import Utilities
+
+if not hasattr(tokenize, 'NL'):
+ raise ValueError("tokenize.NL doesn't exist -- tokenize module too old")
+
+__all__ = ["check", "NannyNag", "process_tokens"]
+
+class NannyNag(Exception):
+ """
+ Raised by tokeneater() if detecting an ambiguous indent.
+ Captured and handled in check().
+ """
+ def __init__(self, lineno, msg, line):
+ """
+ Constructor
+
+ @param lineno Line number of the ambiguous indent.
+ @param msg Descriptive message assigned to this problem.
+ @param line The offending source line.
+ """
+ self.lineno, self.msg, self.line = lineno, msg, line
+
+ def get_lineno(self):
+ """
+ Method to retrieve the line number.
+
+ @return The line number (integer)
+ """
+ return self.lineno
+
+ def get_msg(self):
+ """
+ Method to retrieve the message.
+
+ @return The error message (string)
+ """
+ return self.msg
+
+ def get_line(self):
+ """
+ Method to retrieve the offending line.
+
+ @return The line of code (string)
+ """
+ return self.line
+
+def check(file):
+ """
+ Private function to check one Python source file for whitespace related problems.
+
+ @param file source filename (string)
+ @return A tuple indicating status (True = an error was found), the
+ filename, the linenumber and the error message
+ (boolean, string, string, string). The values are only
+ valid, if the status is True.
+ """
+ global indents, check_equal
+ indents = [Whitespace("")]
+ check_equal = 0
+
+ try:
+ f = open(file)
+ except IOError, msg:
+ return (True, file, "1", "I/O Error: %s" % unicode(msg))
+
+ try:
+ text = Utilities.decode(f.read())[0].encode('utf-8')
+ finally:
+ f.close()
+
+ # convert eols
+ text = Utilities.convertLineEnds(text, os.linesep)
+
+ source = cStringIO.StringIO(text)
+ try:
+ process_tokens(tokenize.generate_tokens(source.readline))
+
+ except tokenize.TokenError, msg:
+ f.close()
+ return (True, file, "1", "Token Error: %s" % unicode(msg))
+
+ except IndentationError, err:
+ f.close()
+ return (True, file, err.lineno, "Indentation Error: %s" % unicode(err.msg))
+
+ except NannyNag, nag:
+ badline = nag.get_lineno()
+ line = nag.get_line()
+ f.close()
+ return (True, file, str(badline), line)
+
+ except Exception, err:
+ f.close()
+ return (True, file, "1", "Unspecific Error: %s" % unicode(err))
+
+ f.close()
+ return (False, None, None, None)
+
+class Whitespace(object):
+ """
+ Class implementing the whitespace checker.
+ """
+ # the characters used for space and tab
+ S, T = ' \t'
+
+ # members:
+ # raw
+ # the original string
+ # n
+ # the number of leading whitespace characters in raw
+ # nt
+ # the number of tabs in raw[:n]
+ # norm
+ # the normal form as a pair (count, trailing), where:
+ # count
+ # a tuple such that raw[:n] contains count[i]
+ # instances of S * i + T
+ # trailing
+ # the number of trailing spaces in raw[:n]
+ # It's A Theorem that m.indent_level(t) ==
+ # n.indent_level(t) for all t >= 1 iff m.norm == n.norm.
+ # is_simple
+ # true iff raw[:n] is of the form (T*)(S*)
+
+ def __init__(self, ws):
+ """
+ Constructor
+
+ @param ws The string to be checked.
+ """
+ self.raw = ws
+ S, T = Whitespace.S, Whitespace.T
+ count = []
+ b = n = nt = 0
+ for ch in self.raw:
+ if ch == S:
+ n = n + 1
+ b = b + 1
+ elif ch == T:
+ n = n + 1
+ nt = nt + 1
+ if b >= len(count):
+ count = count + [0] * (b - len(count) + 1)
+ count[b] = count[b] + 1
+ b = 0
+ else:
+ break
+ self.n = n
+ self.nt = nt
+ self.norm = tuple(count), b
+ self.is_simple = len(count) <= 1
+
+ # return length of longest contiguous run of spaces (whether or not
+ # preceding a tab)
+ def longest_run_of_spaces(self):
+ """
+ Method to calculate the length of longest contiguous run of spaces.
+
+ @return The length of longest contiguous run of spaces (whether or not
+ preceding a tab)
+ """
+ count, trailing = self.norm
+ return max(len(count)-1, trailing)
+
+ def indent_level(self, tabsize):
+ """
+ Method to determine the indentation level.
+
+ @param tabsize The length of a tab stop. (integer)
+ @return indentation level (integer)
+ """
+ # count, il = self.norm
+ # for i in range(len(count)):
+ # if count[i]:
+ # il = il + (i/tabsize + 1)*tabsize * count[i]
+ # return il
+
+ # quicker:
+ # il = trailing + sum (i/ts + 1)*ts*count[i] =
+ # trailing + ts * sum (i/ts + 1)*count[i] =
+ # trailing + ts * sum i/ts*count[i] + count[i] =
+ # trailing + ts * [(sum i/ts*count[i]) + (sum count[i])] =
+ # trailing + ts * [(sum i/ts*count[i]) + num_tabs]
+ # and note that i/ts*count[i] is 0 when i < ts
+
+ count, trailing = self.norm
+ il = 0
+ for i in range(tabsize, len(count)):
+ il = il + i/tabsize * count[i]
+ return trailing + tabsize * (il + self.nt)
+
+ # return true iff self.indent_level(t) == other.indent_level(t)
+ # for all t >= 1
+ def equal(self, other):
+ """
+ Method to compare the indentation levels of two Whitespace objects for equality.
+
+ @param other Whitespace object to compare against.
+ @return True, if we compare equal against the other Whitespace object.
+ """
+ return self.norm == other.norm
+
+ # return a list of tuples (ts, i1, i2) such that
+ # i1 == self.indent_level(ts) != other.indent_level(ts) == i2.
+ # Intended to be used after not self.equal(other) is known, in which
+ # case it will return at least one witnessing tab size.
+ def not_equal_witness(self, other):
+ """
+ Method to calculate a tuple of witnessing tab size.
+
+ Intended to be used after not self.equal(other) is known, in which
+ case it will return at least one witnessing tab size.
+
+ @param other Whitespace object to calculate against.
+ @return A list of tuples (ts, i1, i2) such that
+ i1 == self.indent_level(ts) != other.indent_level(ts) == i2.
+ """
+ n = max(self.longest_run_of_spaces(),
+ other.longest_run_of_spaces()) + 1
+ a = []
+ for ts in range(1, n+1):
+ if self.indent_level(ts) != other.indent_level(ts):
+ a.append( (ts,
+ self.indent_level(ts),
+ other.indent_level(ts)) )
+ return a
+
+ # Return True iff self.indent_level(t) < other.indent_level(t)
+ # for all t >= 1.
+ # The algorithm is due to Vincent Broman.
+ # Easy to prove it's correct.
+ # XXXpost that.
+ # Trivial to prove n is sharp (consider T vs ST).
+ # Unknown whether there's a faster general way. I suspected so at
+ # first, but no longer.
+ # For the special (but common!) case where M and N are both of the
+ # form (T*)(S*), M.less(N) iff M.len() < N.len() and
+ # M.num_tabs() <= N.num_tabs(). Proof is easy but kinda long-winded.
+ # XXXwrite that up.
+ # Note that M is of the form (T*)(S*) iff len(M.norm[0]) <= 1.
+ def less(self, other):
+ """
+ Method to compare the indentation level against another Whitespace objects to
+ be smaller.
+
+ @param other Whitespace object to compare against.
+ @return True, if we compare less against the other Whitespace object.
+ """
+ if self.n >= other.n:
+ return False
+ if self.is_simple and other.is_simple:
+ return self.nt <= other.nt
+ n = max(self.longest_run_of_spaces(),
+ other.longest_run_of_spaces()) + 1
+ # the self.n >= other.n test already did it for ts=1
+ for ts in range(2, n+1):
+ if self.indent_level(ts) >= other.indent_level(ts):
+ return False
+ return True
+
+ # return a list of tuples (ts, i1, i2) such that
+ # i1 == self.indent_level(ts) >= other.indent_level(ts) == i2.
+ # Intended to be used after not self.less(other) is known, in which
+ # case it will return at least one witnessing tab size.
+ def not_less_witness(self, other):
+ """
+ Method to calculate a tuple of witnessing tab size.
+
+ Intended to be used after not self.less(other is known, in which
+ case it will return at least one witnessing tab size.
+
+ @param other Whitespace object to calculate against.
+ @return A list of tuples (ts, i1, i2) such that
+ i1 == self.indent_level(ts) >= other.indent_level(ts) == i2.
+ """
+ n = max(self.longest_run_of_spaces(),
+ other.longest_run_of_spaces()) + 1
+ a = []
+ for ts in range(1, n+1):
+ if self.indent_level(ts) >= other.indent_level(ts):
+ a.append( (ts,
+ self.indent_level(ts),
+ other.indent_level(ts)) )
+ return a
+
+def format_witnesses(w):
+ """
+ Function to format the witnesses as a readable string.
+
+ @param w A list of witnesses
+ @return A formated string of the witnesses.
+ """
+ firsts = map(lambda tup: str(tup[0]), w)
+ prefix = "at tab size"
+ if len(w) > 1:
+ prefix = prefix + "s"
+ return prefix + " " + ', '.join(firsts)
+
+def process_tokens(tokens):
+ """
+ Function processing all tokens generated by a tokenizer run.
+
+ @param tokens list of tokens
+ """
+ INDENT = tokenize.INDENT
+ DEDENT = tokenize.DEDENT
+ NEWLINE = tokenize.NEWLINE
+ JUNK = tokenize.COMMENT, tokenize.NL
+ indents = [Whitespace("")]
+ check_equal = 0
+
+ for (type, token, start, end, line) in tokens:
+ if type == NEWLINE:
+ # a program statement, or ENDMARKER, will eventually follow,
+ # after some (possibly empty) run of tokens of the form
+ # (NL | COMMENT)* (INDENT | DEDENT+)?
+ # If an INDENT appears, setting check_equal is wrong, and will
+ # be undone when we see the INDENT.
+ check_equal = 1
+
+ elif type == INDENT:
+ check_equal = 0
+ thisguy = Whitespace(token)
+ if not indents[-1].less(thisguy):
+ witness = indents[-1].not_less_witness(thisguy)
+ msg = "indent not greater e.g. " + format_witnesses(witness)
+ raise NannyNag(start[0], msg, line)
+ indents.append(thisguy)
+
+ elif type == DEDENT:
+ # there's nothing we need to check here! what's important is
+ # that when the run of DEDENTs ends, the indentation of the
+ # program statement (or ENDMARKER) that triggered the run is
+ # equal to what's left at the top of the indents stack
+
+ # Ouch! This assert triggers if the last line of the source
+ # is indented *and* lacks a newline -- then DEDENTs pop out
+ # of thin air.
+ # assert check_equal # else no earlier NEWLINE, or an earlier INDENT
+ check_equal = 1
+
+ del indents[-1]
+
+ elif check_equal and type not in JUNK:
+ # this is the first "real token" following a NEWLINE, so it
+ # must be the first token of the next program statement, or an
+ # ENDMARKER; the "line" argument exposes the leading whitespace
+ # for this statement; in the case of ENDMARKER, line is an empty
+ # string, so will properly match the empty string with which the
+ # "indents" stack was seeded
+ check_equal = 0
+ thisguy = Whitespace(line)
+ if not indents[-1].equal(thisguy):
+ witness = indents[-1].not_equal_witness(thisguy)
+ msg = "indent not equal e.g. " + format_witnesses(witness)
+ raise NannyNag(start[0], msg, line)
