| 1 | #!/usr/bin/env bash
|
| 2 | #
|
| 3 | # Show problems with errexit.
|
| 4 | #
|
| 5 | # Usage:
|
| 6 | # ./errexit-confusion.sh <function name>
|
| 7 |
|
| 8 | set -o nounset
|
| 9 | set -o pipefail
|
| 10 | set -o errexit
|
| 11 |
|
| 12 | log() {
|
| 13 | echo "$@" 1>&2
|
| 14 | }
|
| 15 |
|
| 16 | die() {
|
| 17 | log "$@"
|
| 18 | exit 1
|
| 19 | }
|
| 20 |
|
| 21 | all-passing() {
|
| 22 | bin/osh --parse-and-print-arena foo # This fails
|
| 23 | echo status=$? # succeeds
|
| 24 | }
|
| 25 |
|
| 26 | # Copied from test/common.sh, to show the bug.
|
| 27 |
|
| 28 | # The bug is that errexit is disabled within if. Fixes tried:
|
| 29 | #
|
| 30 | # 1) Putting it on its own line: Then errexit triggers and you don't get the
|
| 31 | # failure message.
|
| 32 | #
|
| 33 | # $func_name 2>&1
|
| 34 | #
|
| 35 | # 2) Disabling with
|
| 36 | #
|
| 37 | # set +o errexit
|
| 38 | # $func_name 2>&1
|
| 39 | # status=$?
|
| 40 | # set -o errexit
|
| 41 | #
|
| 42 | # The problem is that the LAST line of all-passing succeeds. We want it to
|
| 43 | # fail in the middle.
|
| 44 |
|
| 45 | run-other-suite-for-release-OLD() {
|
| 46 | local suite_name=$1
|
| 47 | local func_name=$2
|
| 48 |
|
| 49 | local out=_tmp/other/${suite_name}.txt
|
| 50 | mkdir -p $(dirname $out)
|
| 51 |
|
| 52 | echo
|
| 53 | echo "*** Running test suite '$suite_name' ***"
|
| 54 | echo
|
| 55 |
|
| 56 | if $func_name 2>&1; then
|
| 57 | echo
|
| 58 | log "Test suite '$suite_name' ran without errors. Wrote $out"
|
| 59 | else
|
| 60 | echo
|
| 61 | die "Test suite '$suite_name' failed (running $func_name)"
|
| 62 | fi
|
| 63 | }
|
| 64 |
|
| 65 | # This is an awkward rewrite that works.
|
| 66 | #
|
| 67 | # Again the argv dispatch pattern saves the day! You can test if a function
|
| 68 | # failed while preserving its own errexit semantics!
|
| 69 | #
|
| 70 | # This composes!
|
| 71 |
|
| 72 | run-other-suite-for-release-FIXED() {
|
| 73 | local suite_name=$1
|
| 74 | local func_name=$2
|
| 75 |
|
| 76 | local out=_tmp/other/${suite_name}.txt
|
| 77 | mkdir -p $(dirname $out)
|
| 78 |
|
| 79 | echo
|
| 80 | echo "*** Running test suite '$suite_name' ***"
|
| 81 | echo
|
| 82 |
|
| 83 | local status=0
|
| 84 |
|
| 85 | # Run in a separate SHELL, not just in a separate process. ( $func_name )
|
| 86 | # doesn't work.
|
| 87 | $0 $func_name 2>&1 | tee $out || status=$?
|
| 88 |
|
| 89 | if test $status -eq 0; then
|
| 90 | echo
|
| 91 | log "Test suite '$suite_name' ran without errors. Wrote '$out'"
|
| 92 | else
|
| 93 | echo
|
| 94 | die "Test suite '$suite_name' failed with status $status (running '$func_name', wrote '$out')"
|
| 95 | fi
|
| 96 | }
|
| 97 |
|
| 98 | run-for-release-OLD() {
|
| 99 | run-other-suite-for-release-OLD example-failure all-passing
|
| 100 | }
|
| 101 |
|
| 102 | run-for-release-FIXED() {
|
| 103 | run-other-suite-for-release-FIXED example-failure all-passing
|
| 104 | }
|
| 105 |
|
| 106 | # This could be a blog post:
|
| 107 | #
|
| 108 | # Conditions for the problem:
|
| 109 | # - using errexit (pipefail)
|
| 110 | # - but you want to test if a FUNCTION failed. If you disable errexit, you are
|
| 111 | # changing the semantics of the function!
|
| 112 | #
|
| 113 | # Solution:
|
| 114 | #
|
| 115 | # 1. Use the argv dispatch pattern
|
| 116 | # 2. Use $0 $func_name || status=$?
|
| 117 |
|
| 118 | # -----------------------------------------------------------------------------
|
| 119 |
|
| 120 | # Another different that went away with the FIXED: A case where the stricter
|
| 121 | # behavior of OSH's errexit was triggered.
|
| 122 |
|
| 123 | # Can't set 'errexit' in a context where it's disabled (if, !, && ||,
|
| 124 | # while/until conditions)
|
| 125 | #
|
| 126 | # Arguably this is exposing a bug? errexit is already disabled? May have to
|
| 127 | # revisit this.
|
| 128 |
|
| 129 | test-case-that-sets-errexit() {
|
| 130 | set +o errexit
|
| 131 | echo hi
|
| 132 | }
|
| 133 |
|
| 134 | osh-stricter() {
|
| 135 | run-other-suite-for-release-OLD osh-stricter test-case-that-sets-errexit
|
| 136 | }
|
| 137 |
|
| 138 | "$@"
|
| 139 |
|