1 ##############################################################################
2 #
3 # Copyright (c) 2001, 2002 Zope Corporation and Contributors.
4 # All Rights Reserved.
5 #
6 # This software is subject to the provisions of the Zope Public License,
7 # Version 2.0 (ZPL). A copy of the ZPL should accompany this distribution.
8 # THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
9 # WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
10 # WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
11 # FOR A PARTICULAR PURPOSE
12 #
13 ##############################################################################
14 """
15 Code generator for TALInterpreter intermediate code.
16 """
18 import string
19 import re
20 import cgi
22 from TALDefs import *
24 class TALGenerator:
26 inMacroUse = 0
27 inMacroDef = 0
28 source_file = None
30 def __init__(self, expressionCompiler=None, xml=1, source_file=None):
31 if not expressionCompiler:
32 from DummyEngine import DummyEngine
33 expressionCompiler = DummyEngine()
34 self.expressionCompiler = expressionCompiler
35 self.CompilerError = expressionCompiler.getCompilerError()
36 self.program = []
37 self.stack = []
38 self.todoStack = []
39 self.macros = {}
40 self.slots = {}
41 self.slotStack = []
42 self.xml = xml
43 self.emit("version", TAL_VERSION)
44 self.emit("mode", xml and "xml" or "html")
45 if source_file is not None:
46 self.source_file = source_file
47 self.emit("setSourceFile", source_file)
49 def getCode(self):
50 assert not self.stack
51 assert not self.todoStack
52 return self.optimize(self.program), self.macros
54 def optimize(self, program):
55 output = []
56 collect = []
57 rawseen = cursor = 0
58 if self.xml:
59 endsep = "/>"
60 else:
61 endsep = " />"
62 for cursor in xrange(len(program)+1):
63 try:
64 item = program[cursor]
65 except IndexError:
66 item = (None, None)
67 opcode = item[0]
68 if opcode == "rawtext":
69 collect.append(item[1])
70 continue
71 if opcode == "endTag":
72 collect.append("</%s>" % item[1])
73 continue
74 if opcode == "startTag":
75 if self.optimizeStartTag(collect, item[1], item[2], ">"):
76 continue
77 if opcode == "startEndTag":
78 if self.optimizeStartTag(collect, item[1], item[2], endsep):
79 continue
80 if opcode in ("beginScope", "endScope"):
81 # Push *Scope instructions in front of any text instructions;
82 # this allows text instructions separated only by *Scope
83 # instructions to be joined together.
84 output.append(self.optimizeArgsList(item))
85 continue
86 text = string.join(collect, "")
87 if text:
88 i = string.rfind(text, "\n")
89 if i >= 0:
90 i = len(text) - (i + 1)
91 output.append(("rawtextColumn", (text, i)))
92 else:
93 output.append(("rawtextOffset", (text, len(text))))
94 if opcode != None:
95 output.append(self.optimizeArgsList(item))
96 rawseen = cursor+1
97 collect = []
98 return self.optimizeCommonTriple(output)
100 def optimizeArgsList(self, item):
101 if len(item) == 2:
102 return item
103 else:
104 return item[0], tuple(item[1:])
106 actionIndex = {"replace":0, "insert":1, "metal":2, "tal":3, "xmlns":4,
107 0: 0, 1: 1, 2: 2, 3: 3, 4: 4}
108 def optimizeStartTag(self, collect, name, attrlist, end):
109 if not attrlist:
110 collect.append("<%s%s" % (name, end))
111 return 1
112 opt = 1
113 new = ["<" + name]
114 for i in range(len(attrlist)):
115 item = attrlist[i]
116 if len(item) > 2:
117 opt = 0
118 name, value, action = item[:3]
119 action = self.actionIndex[action]
120 attrlist[i] = (name, value, action) + item[3:]
121 else:
122 if item[1] is None:
123 s = item[0]
124 else:
125 s = "%s=%s" % (item[0], quote(item[1]))
126 attrlist[i] = item[0], s
127 if item[1] is None:
128 new.append(" " + item[0])
129 else:
130 new.append(" %s=%s" % (item[0], quote(item[1])))
131 if opt:
132 new.append(end)
133 collect.extend(new)
134 return opt
136 def optimizeCommonTriple(self, program):
137 if len(program) < 3:
138 return program
139 output = program[:2]
140 prev2, prev1 = output
141 for item in program[2:]:
142 if ( item[0] == "beginScope"
143 and prev1[0] == "setPosition"
144 and prev2[0] == "rawtextColumn"):
145 position = output.pop()[1]
146 text, column = output.pop()[1]
147 prev1 = None, None
148 closeprev = 0
149 if output and output[-1][0] == "endScope":
150 closeprev = 1
151 output.pop()
152 item = ("rawtextBeginScope",
153 (text, column, position, closeprev, item[1]))
154 output.append(item)
155 prev2 = prev1
156 prev1 = item
157 return output
159 def todoPush(self, todo):
160 self.todoStack.append(todo)
162 def todoPop(self):
163 return self.todoStack.pop()
165 def compileExpression(self, expr):
166 try:
167 return self.expressionCompiler.compile(expr)
168 except self.CompilerError, err:
169 raise TALError('%s in expression %s' % (err.args[0], `expr`),
170 self.position)
172 def pushProgram(self):
173 self.stack.append(self.program)
174 self.program = []
176 def popProgram(self):
177 program = self.program
178 self.program = self.stack.pop()
179 return self.optimize(program)
181 def pushSlots(self):
182 self.slotStack.append(self.slots)
183 self.slots = {}
185 def popSlots(self):
186 slots = self.slots
187 self.slots = self.slotStack.pop()
188 return slots
190 def emit(self, *instruction):
191 self.program.append(instruction)
193 def emitStartTag(self, name, attrlist, isend=0):
194 if isend:
195 opcode = "startEndTag"
196 else:
197 opcode = "startTag"
198 self.emit(opcode, name, attrlist)
200 def emitEndTag(self, name):
201 if self.xml and self.program and self.program[-1][0] == "startTag":
202 # Minimize empty element
203 self.program[-1] = ("startEndTag",) + self.program[-1][1:]
204 else:
205 self.emit("endTag", name)
207 def emitOptTag(self, name, optTag, isend):
208 program = self.popProgram() #block
209 start = self.popProgram() #start tag
210 if (isend or not program) and self.xml:
211 # Minimize empty element
212 start[-1] = ("startEndTag",) + start[-1][1:]
213 isend = 1
214 cexpr = optTag[0]
215 if cexpr:
216 cexpr = self.compileExpression(optTag[0])
217 self.emit("optTag", name, cexpr, optTag[1], isend, start, program)
219 def emitRawText(self, text):
220 self.emit("rawtext", text)
222 def emitText(self, text):
223 self.emitRawText(cgi.escape(text))
225 def emitDefines(self, defines):
226 for part in splitParts(defines):
227 m = re.match(
228 r"(?s)\s*(?:(global|local)\s+)?(%s)\s+(.*)\Z" % NAME_RE, part)
229 if not m:
230 raise TALError("invalid define syntax: " + `part`,
231 self.position)
232 scope, name, expr = m.group(1, 2, 3)
233 scope = scope or "local"
234 cexpr = self.compileExpression(expr)
235 if scope == "local":
236 self.emit("setLocal", name, cexpr)
237 else:
238 self.emit("setGlobal", name, cexpr)
240 def emitOnError(self, name, onError):
241 block = self.popProgram()
242 key, expr = parseSubstitution(onError)
243 cexpr = self.compileExpression(expr)
244 if key == "text":
245 self.emit("insertText", cexpr, [])
246 else:
247 assert key == "structure"
248 self.emit("insertStructure", cexpr, {}, [])
249 self.emitEndTag(name)
250 handler = self.popProgram()
251 self.emit("onError", block, handler)
253 def emitCondition(self, expr):
254 cexpr = self.compileExpression(expr)
255 program = self.popProgram()
256 self.emit("condition", cexpr, program)
258 def emitRepeat(self, arg):
259 m = re.match("(?s)\s*(%s)\s+(.*)\Z" % NAME_RE, arg)
260 if not m:
261 raise TALError("invalid repeat syntax: " + `arg`,
262 self.position)
263 name, expr = m.group(1, 2)
264 cexpr = self.compileExpression(expr)
265 program = self.popProgram()
266 self.emit("loop", name, cexpr, program)
268 def emitSubstitution(self, arg, attrDict={}):
269 key, expr = parseSubstitution(arg)
270 cexpr = self.compileExpression(expr)
271 program = self.popProgram()
272 if key == "text":
273 self.emit("insertText", cexpr, program)
274 else:
275 assert key == "structure"
276 self.emit("insertStructure", cexpr, attrDict, program)
278 def emitDefineMacro(self, macroName):
279 program = self.popProgram()
280 macroName = string.strip(macroName)
281 if self.macros.has_key(macroName):
282 raise METALError("duplicate macro definition: %s" % `macroName`,
283 self.position)
284 if not re.match('%s$' % NAME_RE, macroName):
285 raise METALError("invalid macro name: %s" % `macroName`,
286 self.position)
287 self.macros[macroName] = program
288 self.inMacroDef = self.inMacroDef - 1
289 self.emit("defineMacro", macroName, program)
291 def emitUseMacro(self, expr):
292 cexpr = self.compileExpression(expr)
293 program = self.popProgram()
294 self.inMacroUse = 0
295 self.emit("useMacro", expr, cexpr, self.popSlots(), program)
297 def emitDefineSlot(self, slotName):
298 program = self.popProgram()
299 slotName = string.strip(slotName)
300 if not re.match('%s$' % NAME_RE, slotName):
301 raise METALError("invalid slot name: %s" % `slotName`,
302 self.position)
303 self.emit("defineSlot", slotName, program)
305 def emitFillSlot(self, slotName):
306 program = self.popProgram()
307 slotName = string.strip(slotName)
308 if self.slots.has_key(slotName):
309 raise METALError("duplicate fill-slot name: %s" % `slotName`,
310 self.position)
311 if not re.match('%s$' % NAME_RE, slotName):
312 raise METALError("invalid slot name: %s" % `slotName`,
313 self.position)
314 self.slots[slotName] = program
315 self.inMacroUse = 1
316 self.emit("fillSlot", slotName, program)
318 def unEmitWhitespace(self):
319 collect = []
320 i = len(self.program) - 1
321 while i >= 0:
322 item = self.program[i]
323 if item[0] != "rawtext":
324 break
325 text = item[1]
326 if not re.match(r"\A\s*\Z", text):
327 break
328 collect.append(text)
329 i = i-1
330 del self.program[i+1:]
331 if i >= 0 and self.program[i][0] == "rawtext":
332 text = self.program[i][1]
333 m = re.search(r"\s+\Z", text)
334 if m:
335 self.program[i] = ("rawtext", text[:m.start()])
336 collect.append(m.group())
337 collect.reverse()
338 return string.join(collect, "")
340 def unEmitNewlineWhitespace(self):
341 collect = []
342 i = len(self.program)
343 while i > 0:
344 i = i-1
345 item = self.program[i]
346 if item[0] != "rawtext":
347 break
348 text = item[1]
349 if re.match(r"\A[ \t]*\Z", text):
350 collect.append(text)
351 continue
352 m = re.match(r"(?s)^(.*)(\n[ \t]*)\Z", text)
353 if not m:
354 break
355 text, rest = m.group(1, 2)
356 collect.reverse()
357 rest = rest + string.join(collect, "")
358 del self.program[i:]
359 if text:
360 self.emit("rawtext", text)
361 return rest
362 return None
364 def replaceAttrs(self, attrlist, repldict):
365 if not repldict:
366 return attrlist
367 newlist = []
368 for item in attrlist:
369 key = item[0]
370 if repldict.has_key(key):
371 item = item[:2] + ("replace", repldict[key])
372 del repldict[key]
373 newlist.append(item)
374 for key, value in repldict.items(): # Add dynamic-only attributes
375 item = (key, None, "insert", value)
376 newlist.append(item)
377 return newlist
379 def emitStartElement(self, name, attrlist, taldict, metaldict,
380 position=(None, None), isend=0):
381 if not taldict and not metaldict:
382 # Handle the simple, common case
383 self.emitStartTag(name, attrlist, isend)
384 self.todoPush({})
385 if isend:
386 self.emitEndElement(name, isend)
387 return
389 self.position = position
390 for key, value in taldict.items():
391 if key not in KNOWN_TAL_ATTRIBUTES:
392 raise TALError("bad TAL attribute: " + `key`, position)
393 if not (value or key == 'omit-tag'):
394 raise TALError("missing value for TAL attribute: " +
395 `key`, position)
396 for key, value in metaldict.items():
397 if key not in KNOWN_METAL_ATTRIBUTES:
398 raise METALError("bad METAL attribute: " + `key`,
399 position)
400 if not value:
401 raise TALError("missing value for METAL attribute: " +
402 `key`, position)
403 todo = {}
404 defineMacro = metaldict.get("define-macro")
405 useMacro = metaldict.get("use-macro")
406 defineSlot = metaldict.get("define-slot")
407 fillSlot = metaldict.get("fill-slot")
408 define = taldict.get("define")
409 condition = taldict.get("condition")
410 repeat = taldict.get("repeat")
411 content = taldict.get("content")
412 replace = taldict.get("replace")
413 attrsubst = taldict.get("attributes")
414 onError = taldict.get("on-error")
415 omitTag = taldict.get("omit-tag")
416 TALtag = taldict.get("tal tag")
417 if len(metaldict) > 1 and (defineMacro or useMacro):
418 raise METALError("define-macro and use-macro cannot be used "
419 "together or with define-slot or fill-slot",
420 position)
421 if content and replace:
422 raise TALError("content and replace are mutually exclusive",
423 position)
425 repeatWhitespace = None
426 if repeat:
427 # Hack to include preceding whitespace in the loop program
428 repeatWhitespace = self.unEmitNewlineWhitespace()
429 if position != (None, None):
430 # XXX at some point we should insist on a non-trivial position
431 self.emit("setPosition", position)
432 if self.inMacroUse:
433 if fillSlot:
434 self.pushProgram()
435 if self.source_file is not None:
436 self.emit("setSourceFile", self.source_file)
437 todo["fillSlot"] = fillSlot
438 self.inMacroUse = 0
439 else:
440 if fillSlot:
441 raise METALError, ("fill-slot must be within a use-macro",
442 position)
443 if not self.inMacroUse:
444 if defineMacro:
445 self.pushProgram()
446 self.emit("version", TAL_VERSION)
447 self.emit("mode", self.xml and "xml" or "html")
448 if self.source_file is not None:
449 self.emit("setSourceFile", self.source_file)
450 todo["defineMacro"] = defineMacro
451 self.inMacroDef = self.inMacroDef + 1
452 if useMacro:
453 self.pushSlots()
454 self.pushProgram()
455 todo["useMacro"] = useMacro
456 self.inMacroUse = 1
457 if defineSlot:
458 if not self.inMacroDef:
459 raise METALError, (
460 "define-slot must be within a define-macro",
461 position)
462 self.pushProgram()
463 todo["defineSlot"] = defineSlot
465 if taldict:
466 dict = {}
467 for item in attrlist:
468 key, value = item[:2]
469 dict[key] = value
470 self.emit("beginScope", dict)
471 todo["scope"] = 1
472 if onError:
473 self.pushProgram() # handler
474 self.emitStartTag(name, list(attrlist)) # Must copy attrlist!
475 self.pushProgram() # block
476 todo["onError"] = onError
477 if define:
478 self.emitDefines(define)
479 todo["define"] = define
480 if condition:
481 self.pushProgram()
482 todo["condition"] = condition
483 if repeat:
484 todo["repeat"] = repeat
485 self.pushProgram()
486 if repeatWhitespace:
487 self.emitText(repeatWhitespace)
488 if content:
489 todo["content"] = content
490 if replace:
491 todo["replace"] = replace
492 self.pushProgram()
493 optTag = omitTag is not None or TALtag
494 if optTag:
495 todo["optional tag"] = omitTag, TALtag
496 self.pushProgram()
497 if attrsubst:
498 repldict = parseAttributeReplacements(attrsubst)
499 for key, value in repldict.items():
500 repldict[key] = self.compileExpression(value)
501 else:
502 repldict = {}
503 if replace:
504 todo["repldict"] = repldict
505 repldict = {}
506 self.emitStartTag(name, self.replaceAttrs(attrlist, repldict), isend)
507 if optTag:
508 self.pushProgram()
509 if content:
510 self.pushProgram()
511 if todo and position != (None, None):
512 todo["position"] = position
513 self.todoPush(todo)
514 if isend:
515 self.emitEndElement(name, isend)
517 def emitEndElement(self, name, isend=0, implied=0):
518 todo = self.todoPop()
519 if not todo:
520 # Shortcut
521 if not isend:
522 self.emitEndTag(name)
523 return
525 self.position = position = todo.get("position", (None, None))
526 defineMacro = todo.get("defineMacro")
527 useMacro = todo.get("useMacro")
528 defineSlot = todo.get("defineSlot")
529 fillSlot = todo.get("fillSlot")
530 repeat = todo.get("repeat")
531 content = todo.get("content")
532 replace = todo.get("replace")
533 condition = todo.get("condition")
534 onError = todo.get("onError")
535 define = todo.get("define")
536 repldict = todo.get("repldict", {})
537 scope = todo.get("scope")
538 optTag = todo.get("optional tag")
540 if implied > 0:
541 if defineMacro or useMacro or defineSlot or fillSlot:
542 exc = METALError
543 what = "METAL"
544 else:
545 exc = TALError
546 what = "TAL"
547 raise exc("%s attributes on <%s> require explicit </%s>" %
548 (what, name, name), position)
550 if content:
551 self.emitSubstitution(content, {})
552 if optTag:
553 self.emitOptTag(name, optTag, isend)
554 elif not isend:
555 self.emitEndTag(name)
556 if replace:
557 self.emitSubstitution(replace, repldict)
558 if repeat:
559 self.emitRepeat(repeat)
560 if condition:
561 self.emitCondition(condition)
562 if onError:
563 self.emitOnError(name, onError)
564 if scope:
565 self.emit("endScope")
566 if defineSlot:
567 self.emitDefineSlot(defineSlot)
568 if fillSlot:
569 self.emitFillSlot(fillSlot)
570 if useMacro:
571 self.emitUseMacro(useMacro)
572 if defineMacro:
573 self.emitDefineMacro(defineMacro)
575 def test():
576 t = TALGenerator()
577 t.pushProgram()
578 t.emit("bar")
579 p = t.popProgram()
580 t.emit("foo", p)
582 if __name__ == "__main__":
583 test()