| 1 | #
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| 2 | # POSIX rule about special builtins pointed at:
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| 3 | #
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| 4 | # https://www.reddit.com/r/oilshell/comments/5ykpi3/oildev_is_alive/
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| 5 |
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| 6 | #### : is special and prefix assignments persist after special builtins
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| 7 | case $SH in
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| 8 | dash|zsh|*osh)
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| 9 | ;;
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| 10 | *)
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| 11 | # for bash
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| 12 | set -o posix
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| 13 | ;;
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| 14 | esac
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| 15 | foo=bar :
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| 16 | echo foo=$foo
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| 17 | ## STDOUT:
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| 18 | foo=bar
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| 19 | ## END
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| 20 | ## BUG zsh STDOUT:
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| 21 | foo=
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| 22 | ## END
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| 23 |
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| 24 | #### readonly is special and prefix assignments persist
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| 25 |
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| 26 | # Bash only implements it behind the posix option
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| 27 | case $SH in
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| 28 | dash|zsh|*osh)
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| 29 | ;;
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| 30 | *)
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| 31 | # for bash
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| 32 | set -o posix
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| 33 | ;;
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| 34 | esac
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| 35 | foo=bar readonly spam=eggs
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| 36 | echo foo=$foo
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| 37 | echo spam=$spam
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| 38 |
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| 39 | # should NOT be exported
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| 40 | printenv.py foo
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| 41 | printenv.py spam
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| 42 | ## STDOUT:
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| 43 | foo=bar
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| 44 | spam=eggs
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| 45 | None
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| 46 | None
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| 47 | ## END
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| 48 | ## BUG bash STDOUT:
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| 49 | foo=bar
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| 50 | spam=eggs
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| 51 | bar
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| 52 | None
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| 53 | ## END
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| 54 |
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| 55 | #### true is not special
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| 56 | foo=bar true
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| 57 | echo $foo
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| 58 | ## stdout:
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| 59 |
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| 60 | #### Shift is special and the whole script exits if it returns non-zero
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| 61 | test -n "$BASH_VERSION" && set -o posix
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| 62 | set -- a b
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| 63 | shift 3
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| 64 | echo status=$?
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| 65 | ## stdout-json: ""
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| 66 | ## status: 1
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| 67 | ## OK dash status: 2
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| 68 | ## BUG bash/zsh status: 0
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| 69 | ## BUG bash/zsh STDOUT:
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| 70 | status=1
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| 71 | ## END
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| 72 |
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| 73 | #### set is special and fails, even if using || true
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| 74 | shopt -s invalid_ || true
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| 75 | echo ok
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| 76 | set -o invalid_ || true
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| 77 | echo should not get here
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| 78 | ## STDOUT:
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| 79 | ok
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| 80 | ## END
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| 81 | ## status: 1
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| 82 | ## OK dash status: 2
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| 83 | ## BUG bash status: 0
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| 84 | ## BUG bash STDOUT:
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| 85 | ok
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| 86 | should not get here
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| 87 | ## END
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| 88 |
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| 89 | #### Special builtins can't be redefined as functions
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| 90 | # bash manual says they are 'found before' functions.
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| 91 | test -n "$BASH_VERSION" && set -o posix
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| 92 | export() {
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| 93 | echo 'export func'
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| 94 | }
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| 95 | export hi
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| 96 | echo status=$?
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| 97 | ## status: 2
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| 98 | ## BUG mksh/zsh status: 0
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| 99 | ## BUG mksh/zsh stdout: status=0
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| 100 |
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| 101 | #### Non-special builtins CAN be redefined as functions
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| 102 | test -n "$BASH_VERSION" && set -o posix
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| 103 | true() {
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| 104 | echo 'true func'
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| 105 | }
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| 106 | true hi
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| 107 | echo status=$?
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| 108 | ## STDOUT:
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| 109 | true func
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| 110 | status=0
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| 111 | ## END
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