| 1 | #### try usage error |
| 2 | |
| 3 | # Irony: we can't fail that hard here because errexit is disabled before |
| 4 | # we enable it. |
| 5 | # TODO: We could special case this perhaps |
| 6 | |
| 7 | try |
| 8 | echo status=$? |
| 9 | |
| 10 | try -z |
| 11 | echo status=$? |
| 12 | |
| 13 | try --zoo |
| 14 | echo status=$? |
| 15 | |
| 16 | # -- is allowed |
| 17 | try -- echo hi |
| 18 | |
| 19 | ## STDOUT: |
| 20 | status=2 |
| 21 | status=2 |
| 22 | status=2 |
| 23 | hi |
| 24 | ## END |
| 25 | |
| 26 | #### try sets _status |
| 27 | myproc() { |
| 28 | echo 'myproc' |
| 29 | return 42 |
| 30 | } |
| 31 | |
| 32 | try myproc |
| 33 | echo dollar=$? |
| 34 | echo _status=$_status |
| 35 | |
| 36 | ( exit 9 ) |
| 37 | echo dollar=$? |
| 38 | echo _status=$_status |
| 39 | |
| 40 | ## STDOUT: |
| 41 | myproc |
| 42 | dollar=0 |
| 43 | _status=42 |
| 44 | dollar=9 |
| 45 | _status=42 |
| 46 | ## END |
| 47 | |
| 48 | |
| 49 | #### try with and without errexit |
| 50 | shopt --set parse_brace parse_proc |
| 51 | |
| 52 | myproc() { |
| 53 | echo before |
| 54 | false |
| 55 | echo after |
| 56 | } |
| 57 | |
| 58 | try myproc |
| 59 | echo status=$_status |
| 60 | |
| 61 | echo --- |
| 62 | try { |
| 63 | echo 'block' |
| 64 | myproc |
| 65 | } |
| 66 | echo status=$_status |
| 67 | |
| 68 | echo === |
| 69 | set -o errexit |
| 70 | |
| 71 | try myproc |
| 72 | echo status=$_status |
| 73 | |
| 74 | echo --- |
| 75 | try { |
| 76 | echo 'block' |
| 77 | myproc |
| 78 | } |
| 79 | echo status=$_status |
| 80 | |
| 81 | ## STDOUT: |
| 82 | before |
| 83 | status=1 |
| 84 | --- |
| 85 | block |
| 86 | before |
| 87 | status=1 |
| 88 | === |
| 89 | before |
| 90 | status=1 |
| 91 | --- |
| 92 | block |
| 93 | before |
| 94 | status=1 |
| 95 | ## END |
| 96 | |
| 97 | #### try takes a block |
| 98 | shopt --set parse_brace |
| 99 | |
| 100 | myproc() { |
| 101 | echo 'myproc' |
| 102 | return 42 |
| 103 | } |
| 104 | |
| 105 | try { |
| 106 | myproc |
| 107 | } |
| 108 | echo dollar=$? |
| 109 | echo _status=$_status |
| 110 | |
| 111 | # It works the same with errexit |
| 112 | set -o errexit |
| 113 | |
| 114 | try { |
| 115 | myproc |
| 116 | } |
| 117 | echo dollar=$? |
| 118 | echo _status=$_status |
| 119 | |
| 120 | ## STDOUT: |
| 121 | myproc |
| 122 | dollar=0 |
| 123 | _status=42 |
| 124 | myproc |
| 125 | dollar=0 |
| 126 | _status=42 |
| 127 | ## END |
| 128 | |
| 129 | #### try with _pipeline_status and PIPESTATUS |
| 130 | shopt --set parse_brace parse_at |
| 131 | set -o errexit |
| 132 | |
| 133 | try { |
| 134 | ls /bad | wc -l |
| 135 | } |
| 136 | echo p @_pipeline_status |
| 137 | echo p @PIPESTATUS |
| 138 | echo _status=$_status # 0 because pipefail is off |
| 139 | |
| 140 | echo --- |
| 141 | set -o pipefail |
| 142 | try { |
| 143 | ls /bad | wc -l |
| 144 | } |
| 145 | echo p @_pipeline_status |
| 146 | echo p @PIPESTATUS |
| 147 | echo _status=$_status # changed to 2 because of pipefail |
| 148 | |
| 149 | ## STDOUT: |
| 150 | 0 |
| 151 | p 2 0 |
| 152 | p 2 0 |
| 153 | _status=0 |
| 154 | --- |
| 155 | 0 |
| 156 | p 2 0 |
| 157 | p 2 0 |
| 158 | _status=2 |
| 159 | ## END |
| 160 | |
| 161 | #### try with _process_sub_status |
| 162 | shopt --set parse_brace parse_at |
| 163 | set -o errexit |
| 164 | |
| 165 | touch right.txt |
| 166 | |
| 167 | try { |
| 168 | diff -q <(sort OOPS) <(sort right.txt) |
| 169 | } |
| 170 | echo p @_process_sub_status |
| 171 | echo _status=$_status |
| 172 | |
| 173 | echo --- |
| 174 | shopt --set process_sub_fail |
| 175 | try { |
| 176 | diff -q <(sort OOPS) <(sort right.txt) |
| 177 | } |
| 178 | echo p @_process_sub_status |
| 179 | echo _status=$_status # changed to 2 because of process_sub_fail |
| 180 | |
| 181 | ## STDOUT: |
| 182 | p 2 0 |
| 183 | _status=0 |
| 184 | --- |
| 185 | p 2 0 |
| 186 | _status=2 |
| 187 | ## END |
| 188 | |
| 189 | #### try error handling idioms |
| 190 | shopt --set parse_paren parse_brace parse_at |
| 191 | |
| 192 | myproc() { |
| 193 | return 42 |
| 194 | } |
| 195 | |
| 196 | try myproc |
| 197 | if (_status === 0) { |
| 198 | echo 'OK' |
| 199 | } |
| 200 | |
| 201 | try myproc |
| 202 | if (_status !== 0) { |
| 203 | echo 'fail' |
| 204 | } |
| 205 | |
| 206 | try { |
| 207 | ls /nonexistent | wc -l |
| 208 | } |
| 209 | # make sure it's integer comparison |
| 210 | if (_pipeline_status[0] !== 0) { |
| 211 | echo 'pipeline failed:' @_pipeline_status |
| 212 | } |
| 213 | |
| 214 | try { |
| 215 | diff <(sort XX) <(sort YY) |
| 216 | } |
| 217 | # make sure it's integer comparison |
| 218 | if (_process_sub_status[0] !== 0) { |
| 219 | echo 'process sub failed:' @_process_sub_status |
| 220 | } |
| 221 | |
| 222 | ## STDOUT: |
| 223 | fail |
| 224 | 0 |
| 225 | pipeline failed: 2 0 |
| 226 | process sub failed: 2 2 |
| 227 | ## END |
| 228 | |
| 229 | #### try can handled failed var, setvar, etc. |
| 230 | shopt --set parse_brace parse_proc |
| 231 | |
| 232 | try { |
| 233 | echo hi |
| 234 | var x = 1 / 0 |
| 235 | echo 'should not get here' |
| 236 | } |
| 237 | echo div $_status |
| 238 | |
| 239 | try { |
| 240 | var a = [] |
| 241 | setvar item = a[1] |
| 242 | echo 'should not get here' |
| 243 | } |
| 244 | echo index $_status |
| 245 | |
| 246 | try { |
| 247 | var d = {} |
| 248 | setvar item = d['mykey'] |
| 249 | echo 'should not get here' |
| 250 | } |
| 251 | echo key $_status |
| 252 | |
| 253 | try { |
| 254 | setvar item = d->mykey |
| 255 | echo 'should not get here' |
| 256 | } |
| 257 | echo arrow $_status |
| 258 | |
| 259 | ## STDOUT: |
| 260 | hi |
| 261 | div 3 |
| 262 | index 3 |
| 263 | key 3 |
| 264 | arrow 3 |
| 265 | ## END |
| 266 | |
| 267 | # nothing on stderr because it's caught! |
| 268 | |
| 269 | ## STDERR: |
| 270 | ## END |
| 271 | |
| 272 | #### try can handled failed expr sub |
| 273 | shopt --set parse_brace parse_proc |
| 274 | |
| 275 | try { |
| 276 | echo hi |
| 277 | |
| 278 | var d = {} |
| 279 | echo "result = $[d->BAD]" |
| 280 | echo 'should not get here' |
| 281 | } |
| 282 | echo _status=$_status |
| 283 | ## STDOUT: |
| 284 | hi |
| 285 | _status=3 |
| 286 | ## END |
| 287 | ## STDERR: |
| 288 | ## END |
| 289 | |
| 290 | #### try with failed command sub within expression |
| 291 | shopt --set parse_brace parse_proc |
| 292 | |
| 293 | try { |
| 294 | echo hi |
| 295 | var x = $(exit 42) # errexit |
| 296 | echo bye |
| 297 | } |
| 298 | echo try $_status |
| 299 | |
| 300 | # Note that there's no way to retrieve this status WITHOUT try |
| 301 | # var x = $(exit 42) # errexit |
| 302 | |
| 303 | ## STDOUT: |
| 304 | hi |
| 305 | try 42 |
| 306 | ## END |
| 307 | |
| 308 | #### Uncaught expression error exits status 3 |
| 309 | $SH -c ' |
| 310 | shopt --set parse_proc |
| 311 | |
| 312 | # errexit does not need to be! |
| 313 | |
| 314 | var x = 42 / 0 |
| 315 | echo inside=$? |
| 316 | ' |
| 317 | echo outside=$? |
| 318 | ## STDOUT: |
| 319 | outside=3 |
| 320 | ## END |
| 321 | |
| 322 | #### boolstatus with external command |
| 323 | |
| 324 | set -o errexit |
| 325 | |
| 326 | echo hi > file.txt |
| 327 | |
| 328 | if boolstatus grep pat file.txt; then |
| 329 | echo 'match' |
| 330 | else |
| 331 | echo 'no match' |
| 332 | fi |
| 333 | |
| 334 | # file doesn't exist |
| 335 | if boolstatus grep pat BAD; then |
| 336 | echo 'match' |
| 337 | else |
| 338 | echo 'no match' |
| 339 | fi |
| 340 | |
| 341 | echo DONE |
| 342 | ## status: 2 |
| 343 | ## STDOUT: |
| 344 | no match |
| 345 | ## END |
| 346 | |
| 347 | #### boolstatus disallows procs with strict_errexit |
| 348 | set -o errexit |
| 349 | shopt -s strict_errexit |
| 350 | |
| 351 | echo hi > file.txt |
| 352 | |
| 353 | not-found() { |
| 354 | echo not-found |
| 355 | grep pat file.txt |
| 356 | echo not-found |
| 357 | } |
| 358 | |
| 359 | bad() { |
| 360 | echo bad |
| 361 | grep pat BAD # exits with code 2 |
| 362 | echo bad |
| 363 | } |
| 364 | |
| 365 | if boolstatus not-found; then |
| 366 | echo 'match' |
| 367 | else |
| 368 | echo 'no match' |
| 369 | fi |
| 370 | |
| 371 | if boolstatus bad; then |
| 372 | echo 'match' |
| 373 | else |
| 374 | echo 'no match' |
| 375 | fi |
| 376 | |
| 377 | ## status: 1 |
| 378 | ## STDOUT: |
| 379 | ## END |
| 380 | |
| 381 | #### boolstatus can call a function without strict_errexit (not recommended) |
| 382 | set -o errexit |
| 383 | |
| 384 | echo hi > file.txt |
| 385 | |
| 386 | not-found() { |
| 387 | echo not-found |
| 388 | grep pat file.txt |
| 389 | local status=$? |
| 390 | if test "$status" -ne 0; then |
| 391 | return $status |
| 392 | fi |
| 393 | echo not-found |
| 394 | } |
| 395 | |
| 396 | bad() { |
| 397 | echo bad |
| 398 | grep pat BAD # exits with code 2 |
| 399 | local status=$? |
| 400 | if test "$status" -ne 0; then |
| 401 | return $status |
| 402 | fi |
| 403 | echo bad |
| 404 | } |
| 405 | |
| 406 | if boolstatus not-found; then |
| 407 | echo 'match' |
| 408 | else |
| 409 | echo 'no match' |
| 410 | fi |
| 411 | |
| 412 | if boolstatus bad; then |
| 413 | echo 'match' |
| 414 | else |
| 415 | echo 'no match' |
| 416 | fi |
| 417 | |
| 418 | ## status: 2 |
| 419 | ## STDOUT: |
| 420 | not-found |
| 421 | no match |
| 422 | bad |
| 423 | ## END |
| 424 |