-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathpeg-tests.el
367 lines (335 loc) · 13.3 KB
/
peg-tests.el
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
;;; peg-tests.el --- Tests of PEG parsers -*- lexical-binding: t; -*-
;; Copyright (C) 2008-2022 Free Software Foundation, Inc.
;; This program is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.
;; This program is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;; GNU General Public License for more details.
;; You should have received a copy of the GNU General Public License
;; along with this program. If not, see <https://www.gnu.org/licenses/>.
;;; Commentary:
;; Tests and examples, that used to live in peg.el wrapped inside an `eval'.
;;; Code:
(require 'peg)
(require 'ert)
;;; Tests:
(defmacro peg-parse-string (pex string &optional noerror)
"Parse STRING according to PEX.
If NOERROR is non-nil, push nil resp. t if the parse failed
resp. succeeded instead of signaling an error."
(let ((oldstyle (consp (car-safe pex)))) ;PEX is really a list of rules.
`(with-temp-buffer
(insert ,string)
(goto-char (point-min))
,(if oldstyle
`(with-peg-rules ,pex
(peg-run (peg ,(caar pex))
,(unless noerror '#'peg-signal-failure)))
`(peg-run (peg ,pex)
,(unless noerror '#'peg-signal-failure))))))
(define-peg-rule peg-test-natural ()
[0-9] (* [0-9]))
(ert-deftest peg-test ()
(should (peg-parse-string peg-test-natural "99 bottles" t))
(should (peg-parse-string ((s "a")) "a" t))
(should (not (peg-parse-string ((s "a")) "b" t)))
(should (peg-parse-string ((s (not "a"))) "b" t))
(should (not (peg-parse-string ((s (not "a"))) "a" t)))
(should (peg-parse-string ((s (if "a"))) "a" t))
(should (not (peg-parse-string ((s (if "a"))) "b" t)))
(should (peg-parse-string ((s "ab")) "ab" t))
(should (not (peg-parse-string ((s "ab")) "ba" t)))
(should (not (peg-parse-string ((s "ab")) "a" t)))
(should (peg-parse-string ((s (range ?0 ?9))) "0" t))
(should (not (peg-parse-string ((s (range ?0 ?9))) "a" t)))
(should (peg-parse-string ((s [0-9])) "0" t))
(should (not (peg-parse-string ((s [0-9])) "a" t)))
(should (not (peg-parse-string ((s [0-9])) "" t)))
(should (peg-parse-string ((s (any))) "0" t))
(should (not (peg-parse-string ((s (any))) "" t)))
(should (peg-parse-string ((s (eob))) "" t))
(should (peg-parse-string ((s (not (eob)))) "a" t))
(should (peg-parse-string ((s (or "a" "b"))) "a" t))
(should (peg-parse-string ((s (or "a" "b"))) "b" t))
(should (not (peg-parse-string ((s (or "a" "b"))) "c" t)))
(should (peg-parse-string (and "a" "b") "ab" t))
(should (peg-parse-string ((s (and "a" "b"))) "abc" t))
(should (not (peg-parse-string (and "a" "b") "ba" t)))
(should (peg-parse-string ((s (and "a" "b" "c"))) "abc" t))
(should (peg-parse-string ((s (* "a") "b" (eob))) "b" t))
(should (peg-parse-string ((s (* "a") "b" (eob))) "ab" t))
(should (peg-parse-string ((s (* "a") "b" (eob))) "aaab" t))
(should (not (peg-parse-string ((s (* "a") "b" (eob))) "abc" t)))
(should (peg-parse-string ((s "")) "abc" t))
(should (peg-parse-string ((s "" (eob))) "" t))
(should (peg-parse-string ((s (opt "a") "b")) "abc" t))
(should (peg-parse-string ((s (opt "a") "b")) "bc" t))
(should (not (peg-parse-string ((s (or))) "ab" t)))
(should (peg-parse-string ((s (and))) "ab" t))
(should (peg-parse-string ((s (and))) "" t))
(should (peg-parse-string ((s ["^"])) "^" t))
(should (peg-parse-string ((s ["^a"])) "a" t))
(should (peg-parse-string ["-"] "-" t))
(should (peg-parse-string ((s ["]-"])) "]" t))
(should (peg-parse-string ((s ["^]"])) "^" t))
(should (peg-parse-string ((s [alpha])) "z" t))
(should (not (peg-parse-string ((s [alpha])) "0" t)))
(should (not (peg-parse-string ((s [alpha])) "" t)))
(should (not (peg-parse-string ((s ["][:alpha:]"])) "z" t)))
(should (peg-parse-string ((s (bob))) "" t))
(should (peg-parse-string ((s (bos))) "x" t))
(should (not (peg-parse-string ((s (bos))) " x" t)))
(should (peg-parse-string ((s "x" (eos))) "x" t))
(should (peg-parse-string ((s (syntax-class whitespace))) " " t))
(should (peg-parse-string ((s (= "foo"))) "foo" t))
(should (let ((f "foo")) (peg-parse-string ((s (= f))) "foo" t)))
(should (not (peg-parse-string ((s (= "foo"))) "xfoo" t)))
(should (equal (peg-parse-string ((s `(-- 1 2))) "") '(2 1)))
(should (equal (peg-parse-string ((s `(-- 1 2) `(a b -- a b))) "") '(2 1)))
(should (equal (peg-parse-string ((s (or (and (any) s)
(substring [0-9]))))
"ab0cd1ef2gh")
'("2")))
;; The PEG rule `other' doesn't exist, which will cause a byte-compiler
;; warning, but not an error at run time because the rule is not actually
;; used in this particular case.
(should (equal (peg-parse-string ((s (substring (or "a" other)))
;; Unused left-recursive rule, should
;; cause a byte-compiler warning.
(r (* "a") r))
"af")
'("a")))
(should (equal (peg-parse-string ((s (list x y))
(x `(-- 1))
(y `(-- 2)))
"")
'((1 2))))
(should (equal (peg-parse-string ((s (list (* x)))
(x "" `(-- 'x)))
"xxx")
;; The empty loop body should be matched once!
'((x))))
(should (equal (peg-parse-string ((s (list (* x)))
(x "x" `(-- 'x)))
"xxx")
'((x x x))))
(should (equal (peg-parse-string ((s (region (* x)))
(x "x" `(-- 'x)))
"xxx")
;; FIXME: Since string positions start at 0, this should
;; really be '(3 x x x 0) !!
'(4 x x x 1)))
(should (equal (peg-parse-string ((s (region (list (* x))))
(x "x" `(-- 'x 'y)))
"xxx")
'(4 (x y x y x y) 1)))
(should (equal (with-temp-buffer
(save-excursion (insert "abcdef"))
(list
(peg-run (peg "a"
(replace "bc" "x")
(replace "de" "y")
"f"))
(buffer-string)))
'(t "axyf")))
(with-temp-buffer
(insert "toro")
(goto-char (point-min))
(should (peg-run (peg "to")))
(should-not (peg-run (peg "to")))
(should (peg-run (peg "ro")))
(should (eobp)))
(with-temp-buffer
(insert " ")
(goto-char (point-min))
(peg-run (peg (+ (syntax-class whitespace))))
(should (eobp)))
)
;;; Examples:
;; peg-ex-recognize-int recognizes integers. An integer begins with a
;; optional sign, then follows one or more digits. Digits are all
;; characters from 0 to 9.
;;
;; Notes:
;; 1) "" matches the empty sequence, i.e. matches without consuming
;; input.
;; 2) [0-9] is the character range from 0 to 9. This can also be
;; written as (range ?0 ?9). Note that 0-9 is a symbol.
(defun peg-ex-recognize-int ()
(with-peg-rules ((number sign digit (* digit))
(sign (or "+" "-" ""))
(digit [0-9]))
(peg-run (peg number))))
;; peg-ex-parse-int recognizes integers and computes the corresponding
;; value. The grammar is the same as for `peg-ex-recognize-int'
;; augmented with parsing actions. Unfortunaletly, the actions add
;; quite a bit of clutter.
;;
;; The actions for the sign rule push -1 on the stack for a minus sign
;; and 1 for plus or no sign.
;;
;; The action for the digit rule pushes the value for a single digit.
;;
;; The action `(a b -- (+ (* a 10) b)), takes two items from the stack
;; and pushes the first digit times 10 added to the second digit.
;;
;; The action `(sign val -- (* sign val)), multiplies val with the
;; sign (1 or -1).
(defun peg-ex-parse-int ()
(with-peg-rules ((number sign digit (* digit
`(a b -- (+ (* a 10) b)))
`(sign val -- (* sign val)))
(sign (or (and "+" `(-- 1))
(and "-" `(-- -1))
(and "" `(-- 1))))
(digit [0-9] `(-- (- (char-before) ?0))))
(peg-run (peg number))))
;; Put point after the ) and press C-x C-e
;; (peg-ex-parse-int)-234234
;; Parse arithmetic expressions and compute the result as side effect.
(defun peg-ex-arith ()
(peg-parse
(expr _ sum eol)
(sum product (* (or (and "+" _ product `(a b -- (+ a b)))
(and "-" _ product `(a b -- (- a b))))))
(product value (* (or (and "*" _ value `(a b -- (* a b)))
(and "/" _ value `(a b -- (/ a b))))))
(value (or (and (substring number) `(string -- (string-to-number string)))
(and "(" _ sum ")" _)))
(number (+ [0-9]) _)
(_ (* [" \t"]))
(eol (or "\n" "\r\n" "\r"))))
;; (peg-ex-arith) 1 + 2 * 3 * (4 + 5)
;; (peg-ex-arith) 1 + 2 ^ 3 * (4 + 5) ; fails to parse
;; Parse URI according to RFC 2396.
(defun peg-ex-uri ()
(peg-parse
(URI-reference (or absoluteURI relativeURI)
(or (and "#" (substring fragment))
`(-- nil))
`(scheme user host port path query fragment --
(list :scheme scheme :user user
:host host :port port
:path path :query query
:fragment fragment)))
(absoluteURI (substring scheme) ":" (or hier-part opaque-part))
(hier-part ;(-- user host port path query)
(or net-path
(and `(-- nil nil nil)
abs-path))
(or (and "?" (substring query))
`(-- nil)))
(net-path "//" authority (or abs-path `(-- nil)))
(abs-path "/" path-segments)
(path-segments segment (list (* "/" segment)) `(s l -- (cons s l)))
(segment (substring (* pchar) (* ";" param)))
(param (* pchar))
(pchar (or unreserved escaped [":@&=+$,"]))
(query (* uric))
(fragment (* uric))
(relativeURI (or net-path abs-path rel-path) (opt "?" query))
(rel-path rel-segment (opt abs-path))
(rel-segment (+ unreserved escaped [";@&=+$,"]))
(authority (or server reg-name))
(server (or (and (or (and (substring userinfo) "@")
`(-- nil))
hostport)
`(-- nil nil nil)))
(userinfo (* (or unreserved escaped [";:&=+$,"])))
(hostport (substring host) (or (and ":" (substring port))
`(-- nil)))
(host (or hostname ipv4address))
(hostname (* domainlabel ".") toplabel (opt "."))
(domainlabel alphanum
(opt (* (or alphanum "-") (if alphanum))
alphanum))
(toplabel alpha
(* (or alphanum "-") (if alphanum))
alphanum)
(ipv4address (+ digit) "." (+ digit) "." (+ digit) "." (+ digit))
(port (* digit))
(scheme alpha (* (or alpha digit ["+-."])))
(reg-name (or unreserved escaped ["$,;:@&=+"]))
(opaque-part uric-no-slash (* uric))
(uric (or reserved unreserved escaped))
(uric-no-slash (or unreserved escaped [";?:@&=+$,"]))
(reserved (set ";/?:@&=+$,"))
(unreserved (or alphanum mark))
(escaped "%" hex hex)
(hex (or digit [A-F] [a-f]))
(mark (set "-_.!~*'()"))
(alphanum (or alpha digit))
(alpha (or lowalpha upalpha))
(lowalpha [a-z])
(upalpha [A-Z])
(digit [0-9])))
;; (peg-ex-uri)http://[email protected]:8080/bar/baz.html?x=1#foo
;; (peg-ex-uri)file:/bar/baz.html?foo=df#x
;; Split STRING where SEPARATOR occurs.
(defun peg-ex-split (string separator)
(peg-parse-string ((s (list (* (* sep) elt)))
(elt (substring (+ (not sep) (any))))
(sep (= separator)))
string))
;; (peg-ex-split "-abc-cd-" "-")
;; Parse a lisp style Sexp.
;; [To keep the example short, ' and . are handled as ordinary symbol.]
(defun peg-ex-lisp ()
(peg-parse
(sexp _ (or string list number symbol))
(_ (* (or [" \n\t"] comment)))
(comment ";" (* (not (or "\n" (eob))) (any)))
(string "\"" (substring (* (not "\"") (any))) "\"")
(number (substring (opt (set "+-")) (+ digit))
(if terminating)
`(string -- (string-to-number string)))
(symbol (substring (and symchar (* (not terminating) symchar)))
`(s -- (intern s)))
(symchar [a-z A-Z 0-9 "-;!#%&'*+,./:;<=>?@[]^_`{|}~"])
(list "(" `(-- (cons nil nil)) `(hd -- hd hd)
(* sexp `(tl e -- (setcdr tl (list e))))
_ ")" `(hd _tl -- (cdr hd)))
(digit [0-9])
(terminating (or (set " \n\t();\"'") (eob)))))
;; (peg-ex-lisp)
;; We try to detect left recursion and report it as error.
(defun peg-ex-left-recursion ()
(eval '(peg-parse (exp (or term
(and exp "+" exp)))
(term (or digit
(and term "*" term)))
(digit [0-9]))
t))
(defun peg-ex-infinite-loop ()
(eval '(peg-parse (exp (* (or "x"
"y"
(action (foo))))))
t))
;; Some efficiency problems:
;; Find the last digit in a string.
;; Recursive definition with excessive stack usage.
(defun peg-ex-last-digit (string)
(peg-parse-string ((s (or (and (any) s)
(substring [0-9]))))
string))
;; (peg-ex-last-digit "ab0cd1ef2gh")
;; (peg-ex-last-digit (make-string 50 ?-))
;; (peg-ex-last-digit (make-string 1000 ?-))
;; Find the last digit without recursion. Doesn't run out of stack,
;; but probably still too inefficient for large inputs.
(defun peg-ex-last-digit2 (string)
(peg-parse-string ((s `(-- nil)
(+ (* (not digit) (any))
(substring digit)
`(_d1 d2 -- d2)))
(digit [0-9]))
string))
;; (peg-ex-last-digit2 "ab0cd1ef2gh")
;; (peg-ex-last-digit2 (concat (make-string 500000 ?-) "8a9b"))
;; (peg-ex-last-digit2 (make-string 500000 ?-))
;; (peg-ex-last-digit2 (make-string 500000 ?5))
(provide 'peg-tests)
;;; peg-tests.el ends here