Explain in 't/README' why it is a bad idea to redirect and verify the stderr of compound commands, in the hope that future contributions will follow this advice and the test suite will keep working with '-x' tracing and /bin/sh.
While at it, since we can now run the test suite with '-x' without needing a Bash version supporting BASH_XTRACEFD, remove the now outdated caution note about non-Bash shells from the description of the '-x' option. Signed-off-by: SZEDER Gábor <szeder....@gmail.com> --- t/README | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) diff --git a/t/README b/t/README index c430e9c52c..615682263e 100644 --- a/t/README +++ b/t/README @@ -84,9 +84,7 @@ appropriately before running "make". -x:: Turn on shell tracing (i.e., `set -x`) during the tests - themselves. Implies `--verbose`. Note that in non-bash shells, - this can cause failures in some tests which redirect and test - the output of shell functions. Use with caution. + themselves. Implies `--verbose`. Ignored in test scripts that set the variable 'test_untraceable' to a non-empty value, unless it's run with a Bash version supporting BASH_XTRACEFD, i.e. v4.1 or later. @@ -455,6 +453,22 @@ Don't: causing the next test to start in an unexpected directory. Do so inside a subshell if necessary. + - save and verify the standard error of compound commands, i.e. group + commands, subshells, and shell functions (except test helper + functions like 'test_must_fail') like this: + + ( cd dir && git cmd ) 2>error && + test_cmp expect error + + When running the test with '-x' tracing, then the trace of commands + executed in the compound command will be included in standard error + as well, quite possibly throwing off the subsequent checks examining + the output. Instead, save only the relevant git command's standard + error: + + ( cd dir && git cmd 2>../error ) && + test_cmp expect error + - Break the TAP output The raw output from your test may be interpreted by a TAP harness. TAP -- 126.96.36.1990.g911b7cc0da