fish-shell/tests/checks/cmdsub-limit.fish
ridiculousfish 534bc66a43 Add a test for background procs in cmdsubs
This adds a test to ensure that if a long running background process is
launched from a command substitution, that process does not cause the
cmdsub to hang. That could easily happen if we just wait for the pipe to
close; this is verifying that we are also checking for the job to complete.
2021-01-07 11:38:52 -08:00

75 lines
2.3 KiB
Fish

# RUN: %fish %s
# This tests various corner cases involving command substitution.
# Test cmdsubs which spawn background processes - see #7559.
# If this hangs, it means that fish keeps trying to read from the write
# end of the cmdsub pipe (which has escaped).
# FIXME: we need to mark full job control for sleep to get its own pgid;
# otherwise $last_pid will return fish's pgid! It's always been so!
status job-control full
echo (command sleep 1000000 & ; set -g sleep_pid $last_pid ; echo local)
# CHECK: local
echo $sleep_pid
# CHECK: {{[1-9]\d*}}
kill $sleep_pid ; echo $status
# CHECK: 0
status job-control interactive
# Test limiting the amount of data we'll substitute.
set fish_read_limit 512
function subme
set -l x (string repeat -n $argv x)
echo $x
end
# Command sub just under the limit should succeed.
set a (subme 511)
set --show a
#CHECK: $a: set in global scope, unexported, with 1 elements
#CHECK: $a[1]: |{{x{510}x}}|
# Command sub at the limit should fail
set b (string repeat -n 512 x)
set saved_status $status
test $saved_status -eq 122
or echo expected status 122, saw $saved_status >&2
set --show b
#CHECKERR: {{.*}}: Too much data emitted by command substitution so it was discarded
#CHECKERR: set b (string repeat -n 512 x)
#CHECKERR: ^
# Command sub over the limit should fail
set c (subme 513)
set --show c
#CHECK: $c: set in global scope, unexported, with 1 elements
#CHECK: $c[1]: ||
#CHECKERR: {{.*}}: Too much data emitted by command substitution so it was discarded
#CHECKERR: set -l x (string repeat -n $argv x)
#CHECKERR: ^
#CHECKERR: in function 'subme' with arguments '513'
#CHECKERR: called on line {{.*}}
#CHECKERR: in command substitution
#CHECKERR: called on line {{.*}}
# Make sure output from builtins outside of command substitution is not affected
string repeat --max 513 a
#CHECK: {{a{512}a}}
# Same builtin in a command substitution is affected
echo this will fail (string repeat --max 513 b) to output anything
set saved_status $status
test $saved_status -eq 122
or echo expected status 122, saw $saved_status >&2
#CHECKERR: {{.*}}: Too much data emitted by command substitution so it was discarded
#CHECKERR: echo this will fail (string repeat --max 513 b) to output anything
#CHECKERR: ^