diff options
Diffstat (limited to 'deps/v8/tools/jsmin.py')
| -rw-r--r-- | deps/v8/tools/jsmin.py | 496 |
1 files changed, 278 insertions, 218 deletions
diff --git a/deps/v8/tools/jsmin.py b/deps/v8/tools/jsmin.py index ae7581413a..fd1abe48fd 100644 --- a/deps/v8/tools/jsmin.py +++ b/deps/v8/tools/jsmin.py @@ -1,218 +1,278 @@ -#!/usr/bin/python
-
-# This code is original from jsmin by Douglas Crockford, it was translated to
-# Python by Baruch Even. The original code had the following copyright and
-# license.
-#
-# /* jsmin.c
-# 2007-05-22
-#
-# Copyright (c) 2002 Douglas Crockford (www.crockford.com)
-#
-# Permission is hereby granted, free of charge, to any person obtaining a copy of
-# this software and associated documentation files (the "Software"), to deal in
-# the Software without restriction, including without limitation the rights to
-# use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
-# of the Software, and to permit persons to whom the Software is furnished to do
-# so, subject to the following conditions:
-#
-# The above copyright notice and this permission notice shall be included in all
-# copies or substantial portions of the Software.
-#
-# The Software shall be used for Good, not Evil.
-#
-# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-# SOFTWARE.
-# */
-
-from StringIO import StringIO
-
-def jsmin(js):
- ins = StringIO(js)
- outs = StringIO()
- JavascriptMinify().minify(ins, outs)
- str = outs.getvalue()
- if len(str) > 0 and str[0] == '\n':
- str = str[1:]
- return str
-
-def isAlphanum(c):
- """return true if the character is a letter, digit, underscore,
- dollar sign, or non-ASCII character.
- """
- return ((c >= 'a' and c <= 'z') or (c >= '0' and c <= '9') or
- (c >= 'A' and c <= 'Z') or c == '_' or c == '$' or c == '\\' or (c is not None and ord(c) > 126));
-
-class UnterminatedComment(Exception):
- pass
-
-class UnterminatedStringLiteral(Exception):
- pass
-
-class UnterminatedRegularExpression(Exception):
- pass
-
-class JavascriptMinify(object):
-
- def _outA(self):
- self.outstream.write(self.theA)
- def _outB(self):
- self.outstream.write(self.theB)
-
- def _get(self):
- """return the next character from stdin. Watch out for lookahead. If
- the character is a control character, translate it to a space or
- linefeed.
- """
- c = self.theLookahead
- self.theLookahead = None
- if c == None:
- c = self.instream.read(1)
- if c >= ' ' or c == '\n':
- return c
- if c == '': # EOF
- return '\000'
- if c == '\r':
- return '\n'
- return ' '
-
- def _peek(self):
- self.theLookahead = self._get()
- return self.theLookahead
-
- def _next(self):
- """get the next character, excluding comments. peek() is used to see
- if an unescaped '/' is followed by a '/' or '*'.
- """
- c = self._get()
- if c == '/' and self.theA != '\\':
- p = self._peek()
- if p == '/':
- c = self._get()
- while c > '\n':
- c = self._get()
- return c
- if p == '*':
- c = self._get()
- while 1:
- c = self._get()
- if c == '*':
- if self._peek() == '/':
- self._get()
- return ' '
- if c == '\000':
- raise UnterminatedComment()
-
- return c
-
- def _action(self, action):
- """do something! What you do is determined by the argument:
- 1 Output A. Copy B to A. Get the next B.
- 2 Copy B to A. Get the next B. (Delete A).
- 3 Get the next B. (Delete B).
- action treats a string as a single character. Wow!
- action recognizes a regular expression if it is preceded by ( or , or =.
- """
- if action <= 1:
- self._outA()
-
- if action <= 2:
- self.theA = self.theB
- if self.theA == "'" or self.theA == '"':
- while 1:
- self._outA()
- self.theA = self._get()
- if self.theA == self.theB:
- break
- if self.theA <= '\n':
- raise UnterminatedStringLiteral()
- if self.theA == '\\':
- self._outA()
- self.theA = self._get()
-
-
- if action <= 3:
- self.theB = self._next()
- if self.theB == '/' and (self.theA == '(' or self.theA == ',' or
- self.theA == '=' or self.theA == ':' or
- self.theA == '[' or self.theA == '?' or
- self.theA == '!' or self.theA == '&' or
- self.theA == '|' or self.theA == ';' or
- self.theA == '{' or self.theA == '}' or
- self.theA == '\n'):
- self._outA()
- self._outB()
- while 1:
- self.theA = self._get()
- if self.theA == '/':
- break
- elif self.theA == '\\':
- self._outA()
- self.theA = self._get()
- elif self.theA <= '\n':
- raise UnterminatedRegularExpression()
- self._outA()
- self.theB = self._next()
-
-
- def _jsmin(self):
- """Copy the input to the output, deleting the characters which are
- insignificant to JavaScript. Comments will be removed. Tabs will be
- replaced with spaces. Carriage returns will be replaced with linefeeds.
- Most spaces and linefeeds will be removed.
- """
- self.theA = '\n'
- self._action(3)
-
- while self.theA != '\000':
- if self.theA == ' ':
- if isAlphanum(self.theB):
- self._action(1)
- else:
- self._action(2)
- elif self.theA == '\n':
- if self.theB in ['{', '[', '(', '+', '-']:
- self._action(1)
- elif self.theB == ' ':
- self._action(3)
- else:
- if isAlphanum(self.theB):
- self._action(1)
- else:
- self._action(2)
- else:
- if self.theB == ' ':
- if isAlphanum(self.theA):
- self._action(1)
- else:
- self._action(3)
- elif self.theB == '\n':
- if self.theA in ['}', ']', ')', '+', '-', '"', '\'']:
- self._action(1)
- else:
- if isAlphanum(self.theA):
- self._action(1)
- else:
- self._action(3)
- else:
- self._action(1)
-
- def minify(self, instream, outstream):
- self.instream = instream
- self.outstream = outstream
- self.theA = '\n'
- self.theB = None
- self.theLookahead = None
-
- self._jsmin()
- self.instream.close()
-
-if __name__ == '__main__':
- import sys
- jsm = JavascriptMinify()
- jsm.minify(sys.stdin, sys.stdout)
+#!/usr/bin/python2.4 + +# Copyright 2009 the V8 project authors. All rights reserved. +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions are +# met: +# +# * Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# * Redistributions in binary form must reproduce the above +# copyright notice, this list of conditions and the following +# disclaimer in the documentation and/or other materials provided +# with the distribution. +# * Neither the name of Google Inc. nor the names of its +# contributors may be used to endorse or promote products derived +# from this software without specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +"""A JavaScript minifier. + +It is far from being a complete JS parser, so there are many valid +JavaScript programs that will be ruined by it. Another strangeness is that +it accepts $ and % as parts of identifiers. It doesn't merge lines or strip +out blank lines in order to ease debugging. Variables at the top scope are +properties of the global object so we can't rename them. It is assumed that +you introduce variables with var as if JavaScript followed C++ scope rules +around curly braces, so the declaration must be above the first use. + +Use as: +import jsmin +minifier = JavaScriptMinifier() +program1 = minifier.JSMinify(program1) +program2 = minifier.JSMinify(program2) +""" + +import re + + +class JavaScriptMinifier(object): + """An object that you can feed code snippets to to get them minified.""" + + def __init__(self): + # We prepopulate the list of identifiers that shouldn't be used. These + # short language keywords could otherwise be used by the script as variable + # names. + self.seen_identifiers = {"do": True, "in": True} + self.identifier_counter = 0 + self.in_comment = False + self.map = {} + self.nesting = 0 + + def LookAtIdentifier(self, m): + """Records identifiers or keywords that we see in use. + + (So we can avoid renaming variables to these strings.) + Args: + m: The match object returned by re.search. + + Returns: + Nothing. + """ + identifier = m.group(1) + self.seen_identifiers[identifier] = True + + def Push(self): + """Called when we encounter a '{'.""" + self.nesting += 1 + + def Pop(self): + """Called when we encounter a '}'.""" + self.nesting -= 1 + # We treat each top-level opening brace as a single scope that can span + # several sets of nested braces. + if self.nesting == 0: + self.map = {} + self.identifier_counter = 0 + + def Declaration(self, m): + """Rewrites bits of the program selected by a regexp. + + These can be curly braces, literal strings, function declarations and var + declarations. (These last two must be on one line including the opening + curly brace of the function for their variables to be renamed). + + Args: + m: The match object returned by re.search. + + Returns: + The string that should replace the match in the rewritten program. + """ + matched_text = m.group(0) + if matched_text == "{": + self.Push() + return matched_text + if matched_text == "}": + self.Pop() + return matched_text + if re.match("[\"'/]", matched_text): + return matched_text + m = re.match(r"var ", matched_text) + if m: + var_names = matched_text[m.end():] + var_names = re.split(r",", var_names) + return "var " + ",".join(map(self.FindNewName, var_names)) + m = re.match(r"(function\b[^(]*)\((.*)\)\{$", matched_text) + if m: + up_to_args = m.group(1) + args = m.group(2) + args = re.split(r",", args) + self.Push() + return up_to_args + "(" + ",".join(map(self.FindNewName, args)) + "){" + + if matched_text in self.map: + return self.map[matched_text] + + return matched_text + + def CharFromNumber(self, number): + """A single-digit base-52 encoding using a-zA-Z.""" + if number < 26: + return chr(number + 97) + number -= 26 + return chr(number + 65) + + def FindNewName(self, var_name): + """Finds a new 1-character or 2-character name for a variable. + + Enters it into the mapping table for this scope. + + Args: + var_name: The name of the variable before renaming. + + Returns: + The new name of the variable. + """ + new_identifier = "" + # Variable names that end in _ are member variables of the global object, + # so they can be visible from code in a different scope. We leave them + # alone. + if var_name in self.map: + return self.map[var_name] + if self.nesting == 0: + return var_name + while True: + identifier_first_char = self.identifier_counter % 52 + identifier_second_char = self.identifier_counter / 52 + new_identifier = self.CharFromNumber(identifier_first_char) + if identifier_second_char != 0: + new_identifier = ( + self.CharFromNumber(identifier_second_char - 1) + new_identifier) + self.identifier_counter += 1 + if not new_identifier in self.seen_identifiers: + break + + self.map[var_name] = new_identifier + return new_identifier + + def RemoveSpaces(self, m): + """Returns literal strings unchanged, replaces other inputs with group 2. + + Other inputs are replaced with the contents of capture 1. This is either + a single space or an empty string. + + Args: + m: The match object returned by re.search. + + Returns: + The string that should be inserted instead of the matched text. + """ + entire_match = m.group(0) + replacement = m.group(1) + if re.match(r"'.*'$", entire_match): + return entire_match + if re.match(r'".*"$', entire_match): + return entire_match + if re.match(r"/.+/$", entire_match): + return entire_match + return replacement + + def JSMinify(self, text): + """The main entry point. Takes a text and returns a compressed version. + + The compressed version hopefully does the same thing. Line breaks are + preserved. + + Args: + text: The text of the code snippet as a multiline string. + + Returns: + The compressed text of the code snippet as a multiline string. + """ + new_lines = [] + for line in re.split(r"\n", text): + line = line.replace("\t", " ") + if self.in_comment: + m = re.search(r"\*/", line) + if m: + line = line[m.end():] + self.in_comment = False + else: + new_lines.append("") + continue + + if not self.in_comment: + line = re.sub(r"/\*.*?\*/", " ", line) + line = re.sub(r"//.*", "", line) + m = re.search(r"/\*", line) + if m: + line = line[:m.start()] + self.in_comment = True + + # Strip leading and trailing spaces. + line = re.sub(r"^ +", "", line) + line = re.sub(r" +$", "", line) + # A regexp that matches a literal string surrounded by "double quotes". + # This regexp can handle embedded backslash-escaped characters including + # embedded backslash-escaped double quotes. + double_quoted_string = r'"(?:[^"\\]|\\.)*"' + # A regexp that matches a literal string surrounded by 'double quotes'. + single_quoted_string = r"'(?:[^'\\]|\\.)*'" + # A regexp that matches a regexp literal surrounded by /slashes/. + slash_quoted_regexp = r"/(?:[^/\\]|\\.)+/" + # Replace multiple spaces with a single space. + line = re.sub("|".join([double_quoted_string, + single_quoted_string, + slash_quoted_regexp, + "( )+"]), + self.RemoveSpaces, + line) + # Strip single spaces unless they have an identifier character both before + # and after the space. % and $ are counted as identifier characters. + line = re.sub("|".join([double_quoted_string, + single_quoted_string, + slash_quoted_regexp, + r"(?<![a-zA-Z_0-9$%]) | (?![a-zA-Z_0-9$%])()"]), + self.RemoveSpaces, + line) + # Collect keywords and identifiers that are already in use. + if self.nesting == 0: + re.sub(r"([a-zA-Z0-9_$%]+)", self.LookAtIdentifier, line) + function_declaration_regexp = ( + r"\bfunction" # Function definition keyword... + r"( [\w$%]+)?" # ...optional function name... + r"\([\w$%,]+\)\{") # ...argument declarations. + # Unfortunately the keyword-value syntax { key:value } makes the key look + # like a variable where in fact it is a literal string. We use the + # presence or absence of a question mark to try to distinguish between + # this case and the ternary operator: "condition ? iftrue : iffalse". + if re.search(r"\?", line): + block_trailing_colon = r"" + else: + block_trailing_colon = r"(?![:\w$%])" + # Variable use. Cannot follow a period precede a colon. + variable_use_regexp = r"(?<![.\w$%])[\w$%]+" + block_trailing_colon + line = re.sub("|".join([double_quoted_string, + single_quoted_string, + slash_quoted_regexp, + r"\{", # Curly braces. + r"\}", + r"\bvar [\w$%,]+", # var declarations. + function_declaration_regexp, + variable_use_regexp]), + self.Declaration, + line) + new_lines.append(line) + + return "\n".join(new_lines) + "\n" |