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Commit | Line | Data |
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878f9883 ES |
1 | #------------------------------------------------------------------------------ |
2 | # Detect broken &&-chains in tests. | |
3 | # | |
4 | # At present, only &&-chains in subshells are examined by this linter; | |
5 | # top-level &&-chains are instead checked directly by the test framework. Like | |
6 | # the top-level &&-chain linter, the subshell linter (intentionally) does not | |
7 | # check &&-chains within {...} blocks. | |
8 | # | |
9 | # Checking for &&-chain breakage is done line-by-line by pure textual | |
10 | # inspection. | |
11 | # | |
12 | # Incomplete lines (those ending with "\") are stitched together with following | |
13 | # lines to simplify processing, particularly of "one-liner" statements. | |
14 | # Top-level here-docs are swallowed to avoid false positives within the | |
15 | # here-doc body, although the statement to which the here-doc is attached is | |
16 | # retained. | |
17 | # | |
18 | # Heuristics are used to detect end-of-subshell when the closing ")" is cuddled | |
19 | # with the final subshell statement on the same line: | |
20 | # | |
21 | # (cd foo && | |
22 | # bar) | |
23 | # | |
24 | # in order to avoid misinterpreting the ")" in constructs such as "x=$(...)" | |
25 | # and "case $x in *)" as ending the subshell. | |
26 | # | |
27 | # Lines missing a final "&&" are flagged with "?!AMP?!", and lines which chain | |
28 | # commands with ";" internally rather than "&&" are flagged "?!SEMI?!". A line | |
29 | # may be flagged for both violations. | |
30 | # | |
31 | # Detection of a missing &&-link in a multi-line subshell is complicated by the | |
32 | # fact that the last statement before the closing ")" must not end with "&&". | |
33 | # Since processing is line-by-line, it is not known whether a missing "&&" is | |
34 | # legitimate or not until the _next_ line is seen. To accommodate this, within | |
35 | # multi-line subshells, each line is stored in sed's "hold" area until after | |
36 | # the next line is seen and processed. If the next line is a stand-alone ")", | |
37 | # then a missing "&&" on the previous line is legitimate; otherwise a missing | |
38 | # "&&" is a break in the &&-chain. | |
39 | # | |
40 | # ( | |
41 | # cd foo && | |
42 | # bar | |
43 | # ) | |
44 | # | |
45 | # In practical terms, when "bar" is encountered, it is flagged with "?!AMP?!", | |
46 | # but when the stand-alone ")" line is seen which closes the subshell, the | |
47 | # "?!AMP?!" violation is removed from the "bar" line (retrieved from the "hold" | |
48 | # area) since the final statement of a subshell must not end with "&&". The | |
49 | # final line of a subshell may still break the &&-chain by using ";" internally | |
50 | # to chain commands together rather than "&&", so "?!SEMI?!" is never removed | |
51 | # from a line (even though "?!AMP?!" might be). | |
52 | # | |
53 | # Care is taken to recognize the last _statement_ of a multi-line subshell, not | |
54 | # necessarily the last textual _line_ within the subshell, since &&-chaining | |
55 | # applies to statements, not to lines. Consequently, blank lines, comment | |
56 | # lines, and here-docs are swallowed (but not the command to which the here-doc | |
57 | # is attached), leaving the last statement in the "hold" area, not the last | |
58 | # line, thus simplifying &&-link checking. | |
59 | # | |
60 | # The final statement before "done" in for- and while-loops, and before "elif", | |
61 | # "else", and "fi" in if-then-else likewise must not end with "&&", thus | |
62 | # receives similar treatment. | |
63 | # | |
c2c29cc0 ES |
64 | # Swallowing here-docs with arbitrary tags requires a bit of finesse. When a |
65 | # line such as "cat <<EOF >out" is seen, the here-doc tag is moved to the front | |
66 | # of the line enclosed in angle brackets as a sentinel, giving "<EOF>cat >out". | |
67 | # As each subsequent line is read, it is appended to the target line and a | |
68 | # (whitespace-loose) back-reference match /^<(.*)>\n\1$/ is attempted to see if | |
69 | # the content inside "<...>" matches the entirety of the newly-read line. For | |
70 | # instance, if the next line read is "some data", when concatenated with the | |
71 | # target line, it becomes "<EOF>cat >out\nsome data", and a match is attempted | |
72 | # to see if "EOF" matches "some data". Since it doesn't, the next line is | |
73 | # attempted. When a line consisting of only "EOF" (and possible whitespace) is | |
74 | # encountered, it is appended to the target line giving "<EOF>cat >out\nEOF", | |
75 | # in which case the "EOF" inside "<...>" does match the text following the | |
76 | # newline, thus the closing here-doc tag has been found. The closing tag line | |
77 | # and the "<...>" prefix on the target line are then discarded, leaving just | |
78 | # the target line "cat >out". | |
79 | # | |
878f9883 ES |
80 | # To facilitate regression testing (and manual debugging), a ">" annotation is |
81 | # applied to the line containing ")" which closes a subshell, ">>" to a line | |
82 | # closing a nested subshell, and ">>>" to a line closing both at once. This | |
83 | # makes it easy to detect whether the heuristics correctly identify | |
84 | # end-of-subshell. | |
85 | #------------------------------------------------------------------------------ | |
86 | ||
87 | # incomplete line -- slurp up next line | |
88 | :squash | |
89 | /\\$/ { | |
ace64e56 ES |
90 | N |
91 | s/\\\n// | |
92 | bsquash | |
878f9883 ES |
93 | } |
94 | ||
95 | # here-doc -- swallow it to avoid false hits within its body (but keep the | |
96 | # command to which it was attached) | |
3042b6bb ES |
97 | /<<[ ]*[-\\'"]*[A-Za-z0-9_]/ { |
98 | s/^\(.*\)<<[ ]*[-\\'"]*\([A-Za-z0-9_][A-Za-z0-9_]*\)['"]*/<\2>\1<</ | |
c2c29cc0 | 99 | s/[ ]*<<// |
a3c4c884 | 100 | :hered |
878f9883 | 101 | N |
c2c29cc0 ES |
102 | /^<\([^>]*\)>.*\n[ ]*\1[ ]*$/!{ |
103 | s/\n.*$// | |
a3c4c884 | 104 | bhered |
c2c29cc0 ES |
105 | } |
106 | s/^<[^>]*>// | |
107 | s/\n.*$// | |
878f9883 ES |
108 | } |
109 | ||
110 | # one-liner "(...) &&" | |
111 | /^[ ]*!*[ ]*(..*)[ ]*&&[ ]*$/boneline | |
112 | ||
113 | # same as above but without trailing "&&" | |
114 | /^[ ]*!*[ ]*(..*)[ ]*$/boneline | |
115 | ||
116 | # one-liner "(...) >x" (or "2>x" or "<x" or "|x" or "&" | |
117 | /^[ ]*!*[ ]*(..*)[ ]*[0-9]*[<>|&]/boneline | |
118 | ||
119 | # multi-line "(...\n...)" | |
120 | /^[ ]*(/bsubshell | |
121 | ||
122 | # innocuous line -- print it and advance to next line | |
123 | b | |
124 | ||
125 | # found one-liner "(...)" -- mark suspect if it uses ";" internally rather than | |
126 | # "&&" (but not ";" in a string) | |
127 | :oneline | |
128 | /;/{ | |
129 | /"[^"]*;[^"]*"/!s/^/?!SEMI?!/ | |
130 | } | |
131 | b | |
132 | ||
133 | :subshell | |
2d9ded8a | 134 | # bare "(" line? -- stash for later printing |
878f9883 | 135 | /^[ ]*([ ]*$/ { |
878f9883 ES |
136 | h |
137 | bnextline | |
138 | } | |
139 | # "(..." line -- split off and stash "(", then process "..." as its own line | |
140 | x | |
141 | s/.*/(/ | |
142 | x | |
143 | s/(// | |
144 | bslurp | |
145 | ||
146 | :nextline | |
147 | N | |
148 | s/.*\n// | |
149 | ||
150 | :slurp | |
151 | # incomplete line "...\" | |
a3c4c884 | 152 | /\\$/bicmplte |
22e3e024 ES |
153 | # multi-line quoted string "...\n..."? |
154 | /"/bdqstring | |
155 | # multi-line quoted string '...\n...'? (but not contraction in string "it's") | |
156 | /'/{ | |
878f9883 ES |
157 | /"[^'"]*'[^'"]*"/!bsqstring |
158 | } | |
d9387114 | 159 | :folded |
878f9883 | 160 | # here-doc -- swallow it |
3042b6bb | 161 | /<<[ ]*[-\\'"]*[A-Za-z0-9_]/bheredoc |
878f9883 ES |
162 | # comment or empty line -- discard since final non-comment, non-empty line |
163 | # before closing ")", "done", "elsif", "else", or "fi" will need to be | |
164 | # re-visited to drop "suspect" marking since final line of those constructs | |
165 | # legitimately lacks "&&", so "suspect" mark must be removed | |
166 | /^[ ]*#/bnextline | |
167 | /^[ ]*$/bnextline | |
168 | # in-line comment -- strip it (but not "#" in a string, Bash ${#...} array | |
169 | # length, or Perforce "//depot/path#42" revision in filespec) | |
170 | /[ ]#/{ | |
171 | /"[^"]*#[^"]*"/!s/[ ]#.*$// | |
172 | } | |
173 | # one-liner "case ... esac" | |
a3c4c884 | 174 | /^[ ]*case[ ]*..*esac/bchkchn |
878f9883 ES |
175 | # multi-line "case ... esac" |
176 | /^[ ]*case[ ]..*[ ]in/bcase | |
177 | # multi-line "for ... done" or "while ... done" | |
178 | /^[ ]*for[ ]..*[ ]in/bcontinue | |
179 | /^[ ]*while[ ]/bcontinue | |
180 | /^[ ]*do[ ]/bcontinue | |
181 | /^[ ]*do[ ]*$/bcontinue | |
182 | /;[ ]*do/bcontinue | |
183 | /^[ ]*done[ ]*&&[ ]*$/bdone | |
184 | /^[ ]*done[ ]*$/bdone | |
185 | /^[ ]*done[ ]*[<>|]/bdone | |
186 | /^[ ]*done[ ]*)/bdone | |
187 | /||[ ]*exit[ ]/bcontinue | |
188 | /||[ ]*exit[ ]*$/bcontinue | |
189 | # multi-line "if...elsif...else...fi" | |
190 | /^[ ]*if[ ]/bcontinue | |
191 | /^[ ]*then[ ]/bcontinue | |
192 | /^[ ]*then[ ]*$/bcontinue | |
193 | /;[ ]*then/bcontinue | |
194 | /^[ ]*elif[ ]/belse | |
195 | /^[ ]*elif[ ]*$/belse | |
196 | /^[ ]*else[ ]/belse | |
197 | /^[ ]*else[ ]*$/belse | |
198 | /^[ ]*fi[ ]*&&[ ]*$/bdone | |
199 | /^[ ]*fi[ ]*$/bdone | |
200 | /^[ ]*fi[ ]*[<>|]/bdone | |
201 | /^[ ]*fi[ ]*)/bdone | |
202 | # nested one-liner "(...) &&" | |
a3c4c884 | 203 | /^[ ]*(.*)[ ]*&&[ ]*$/bchkchn |
878f9883 | 204 | # nested one-liner "(...)" |
a3c4c884 | 205 | /^[ ]*(.*)[ ]*$/bchkchn |
878f9883 | 206 | # nested one-liner "(...) >x" (or "2>x" or "<x" or "|x") |
a3c4c884 | 207 | /^[ ]*(.*)[ ]*[0-9]*[<>|]/bchkchn |
878f9883 ES |
208 | # nested multi-line "(...\n...)" |
209 | /^[ ]*(/bnest | |
210 | # multi-line "{...\n...}" | |
211 | /^[ ]*{/bblock | |
212 | # closing ")" on own line -- exit subshell | |
a3c4c884 | 213 | /^[ ]*)/bclssolo |
878f9883 | 214 | # "$((...))" -- arithmetic expansion; not closing ")" |
a3c4c884 | 215 | /\$(([^)][^)]*))[^)]*$/bchkchn |
878f9883 | 216 | # "$(...)" -- command substitution; not closing ")" |
a3c4c884 | 217 | /\$([^)][^)]*)[^)]*$/bchkchn |
878f9883 | 218 | # multi-line "$(...\n...)" -- command substitution; treat as nested subshell |
06fc5c9f | 219 | /\$([^)]*$/bnest |
878f9883 | 220 | # "=(...)" -- Bash array assignment; not closing ")" |
a3c4c884 | 221 | /=(/bchkchn |
878f9883 ES |
222 | # closing "...) &&" |
223 | /)[ ]*&&[ ]*$/bclose | |
224 | # closing "...)" | |
225 | /)[ ]*$/bclose | |
226 | # closing "...) >x" (or "2>x" or "<x" or "|x") | |
227 | /)[ ]*[<>|]/bclose | |
a3c4c884 | 228 | :chkchn |
878f9883 ES |
229 | # mark suspect if line uses ";" internally rather than "&&" (but not ";" in a |
230 | # string and not ";;" in one-liner "case...esac") | |
231 | /;/{ | |
232 | /;;/!{ | |
233 | /"[^"]*;[^"]*"/!s/^/?!SEMI?!/ | |
234 | } | |
235 | } | |
236 | # line ends with pipe "...|" -- valid; not missing "&&" | |
237 | /|[ ]*$/bcontinue | |
238 | # missing end-of-line "&&" -- mark suspect | |
239 | /&&[ ]*$/!s/^/?!AMP?!/ | |
240 | :continue | |
241 | # retrieve and print previous line | |
242 | x | |
243 | n | |
244 | bslurp | |
245 | ||
246 | # found incomplete line "...\" -- slurp up next line | |
a3c4c884 | 247 | :icmplte |
878f9883 ES |
248 | N |
249 | s/\\\n// | |
250 | bslurp | |
251 | ||
22e3e024 | 252 | # check for multi-line double-quoted string "...\n..." -- fold to one line |
878f9883 | 253 | :dqstring |
22e3e024 ES |
254 | # remove all quote pairs |
255 | s/"\([^"]*\)"/@!\1@!/g | |
256 | # done if no dangling quote | |
257 | /"/!bdqdone | |
258 | # otherwise, slurp next line and try again | |
878f9883 ES |
259 | N |
260 | s/\n// | |
22e3e024 ES |
261 | bdqstring |
262 | :dqdone | |
263 | s/@!/"/g | |
d9387114 | 264 | bfolded |
878f9883 | 265 | |
22e3e024 | 266 | # check for multi-line single-quoted string '...\n...' -- fold to one line |
878f9883 | 267 | :sqstring |
22e3e024 ES |
268 | # remove all quote pairs |
269 | s/'\([^']*\)'/@!\1@!/g | |
270 | # done if no dangling quote | |
271 | /'/!bsqdone | |
272 | # otherwise, slurp next line and try again | |
878f9883 ES |
273 | N |
274 | s/\n// | |
22e3e024 ES |
275 | bsqstring |
276 | :sqdone | |
277 | s/@!/'/g | |
d9387114 | 278 | bfolded |
878f9883 ES |
279 | |
280 | # found here-doc -- swallow it to avoid false hits within its body (but keep | |
c2c29cc0 | 281 | # the command to which it was attached) |
878f9883 | 282 | :heredoc |
3042b6bb | 283 | s/^\(.*\)<<[ ]*[-\\'"]*\([A-Za-z0-9_][A-Za-z0-9_]*\)['"]*/<\2>\1<</ |
c2c29cc0 | 284 | s/[ ]*<<// |
a3c4c884 | 285 | :heredsub |
878f9883 | 286 | N |
c2c29cc0 ES |
287 | /^<\([^>]*\)>.*\n[ ]*\1[ ]*$/!{ |
288 | s/\n.*$// | |
a3c4c884 | 289 | bheredsub |
c2c29cc0 ES |
290 | } |
291 | s/^<[^>]*>// | |
878f9883 | 292 | s/\n.*$// |
d9387114 | 293 | bfolded |
878f9883 ES |
294 | |
295 | # found "case ... in" -- pass through untouched | |
296 | :case | |
297 | x | |
298 | n | |
299 | /^[ ]*esac/bslurp | |
300 | bcase | |
301 | ||
302 | # found "else" or "elif" -- drop "suspect" from final line before "else" since | |
303 | # that line legitimately lacks "&&" | |
304 | :else | |
305 | x | |
306 | s/?!AMP?!// | |
307 | x | |
308 | bcontinue | |
309 | ||
310 | # found "done" closing for-loop or while-loop, or "fi" closing if-then -- drop | |
311 | # "suspect" from final contained line since that line legitimately lacks "&&" | |
312 | :done | |
313 | x | |
314 | s/?!AMP?!// | |
315 | x | |
316 | # is 'done' or 'fi' cuddled with ")" to close subshell? | |
317 | /done.*)/bclose | |
318 | /fi.*)/bclose | |
a3c4c884 | 319 | bchkchn |
878f9883 ES |
320 | |
321 | # found nested multi-line "(...\n...)" -- pass through untouched | |
322 | :nest | |
323 | x | |
a3c4c884 | 324 | :nstslurp |
878f9883 ES |
325 | n |
326 | # closing ")" on own line -- stop nested slurp | |
a3c4c884 | 327 | /^[ ]*)/bnstclose |
878f9883 | 328 | # comment -- not closing ")" if in comment |
a3c4c884 | 329 | /^[ ]*#/bnstcnt |
878f9883 | 330 | # "$((...))" -- arithmetic expansion; not closing ")" |
a3c4c884 | 331 | /\$(([^)][^)]*))[^)]*$/bnstcnt |
878f9883 | 332 | # "$(...)" -- command substitution; not closing ")" |
a3c4c884 | 333 | /\$([^)][^)]*)[^)]*$/bnstcnt |
878f9883 | 334 | # closing "...)" -- stop nested slurp |
a3c4c884 ÆAB |
335 | /)/bnstclose |
336 | :nstcnt | |
878f9883 | 337 | x |
a3c4c884 ÆAB |
338 | bnstslurp |
339 | :nstclose | |
878f9883 ES |
340 | s/^/>>/ |
341 | # is it "))" which closes nested and parent subshells? | |
342 | /)[ ]*)/bslurp | |
a3c4c884 | 343 | bchkchn |
878f9883 ES |
344 | |
345 | # found multi-line "{...\n...}" block -- pass through untouched | |
346 | :block | |
347 | x | |
348 | n | |
349 | # closing "}" -- stop block slurp | |
a3c4c884 | 350 | /}/bchkchn |
878f9883 ES |
351 | bblock |
352 | ||
353 | # found closing ")" on own line -- drop "suspect" from final line of subshell | |
354 | # since that line legitimately lacks "&&" and exit subshell loop | |
a3c4c884 | 355 | :clssolo |
878f9883 ES |
356 | x |
357 | s/?!AMP?!// | |
358 | p | |
359 | x | |
360 | s/^/>/ | |
361 | b | |
362 | ||
363 | # found closing "...)" -- exit subshell loop | |
364 | :close | |
365 | x | |
366 | p | |
367 | x | |
368 | s/^/>/ | |
369 | b |