| Message ID | patch-2.4-3a570321770-20210423T072824Z-avarab@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | test-lib-functions.sh: trickery to make -x less verbose | expand |
Ævar Arnfjörð Bjarmason <avarab@gmail.com> writes: > The goal here is to get rid of the verbosity of having e.g. a "test 2 > -ne 2" line for every "test_cmp". We use "$@" as an argument to "test" > to intentionally feed the "test" operator too many arguments if the > functions are called with too many arguments, thus piggy-backing on it > to check the number of arguments we get. > > Before this for each test_cmp invocation we'd emit: > > + test_cmp expect actual > + test 2 -ne 2 > + eval diff -u "$@" > + diff -u expect actual Quite honestly, I do not see what's bad about that and am not all that sympathetic to the cause behind this series. The developer is asking to debug the test script by passing '-x', and see where the test script is broken. Especially since ... > Now we'll get just: > > + test_cmp expect actual > + eval diff -u "$@" > + diff -u expect actual ... we are not removing the 'eval diff -u "$@"' line, I do not think how a few extra trace output lines coming from sanity check hurts all that much. It is worth paying for to have such basic sanity checks expressed in a more natural way (than "oh, this hack would not work when 'one -a two' is used as a path"), I would think. Thanks.
Ævar Arnfjörð Bjarmason wrote: > diff --git a/t/test-lib-functions.sh b/t/test-lib-functions.sh > index 2914b398470..0adb9fd124d 100644 > --- a/t/test-lib-functions.sh > +++ b/t/test-lib-functions.sh > @@ -756,41 +756,43 @@ test_external_without_stderr () { > } > > # debugging-friendly alternatives to "test [-f|-d|-e]" > -# The commands test the existence or non-existence of $1 > +# The commands test the existence or non-existence of > +# a given argument. > +# > +# The pattern of using "$@" to "test" instead of "$1" is not a bug. We > +# are counting on "test" to error on too many arguments if more than > +# one is given. Checking "$#" explicitly would lead to overly verbose > +# -x output. I would consider adding an extra line. In my mind a comment without a line is for the next function, one with a line is for the section. # function comment function_1 () Versus: # section comment function_1 () function_2 () But I agree with the other comments that it's better inside the function. It's an implementation detail. While I think git tries to follow the self-documenting code style, sometimes it's better to just write the comment. > test_path_is_file () { > - test "$#" -ne 1 && BUG "1 param" > - if ! test -f "$1" > + if ! test -f "$@" if ! test -f "$@" # Rely on test to ensure 1 param > then > - echo "File $1 doesn't exist" > - false > + echo "File $* doesn't exist" > + return 1 > fi > } And yes, I would add that comment to every instance where this trick is used. That way people reading the second or third function don't have to scratch their heads, or miraculously read a comment far above. Cheers.
diff --git a/t/test-lib-functions.sh b/t/test-lib-functions.sh index 2914b398470..0adb9fd124d 100644 --- a/t/test-lib-functions.sh +++ b/t/test-lib-functions.sh @@ -756,41 +756,43 @@ test_external_without_stderr () { } # debugging-friendly alternatives to "test [-f|-d|-e]" -# The commands test the existence or non-existence of $1 +# The commands test the existence or non-existence of +# a given argument. +# +# The pattern of using "$@" to "test" instead of "$1" is not a bug. We +# are counting on "test" to error on too many arguments if more than +# one is given. Checking "$#" explicitly would lead to overly verbose +# -x output. test_path_is_file () { - test "$#" -ne 1 && BUG "1 param" - if ! test -f "$1" + if ! test -f "$@" then - echo "File $1 doesn't exist" - false + echo "File $* doesn't exist" + return 1 fi } test_path_is_dir () { - test "$#" -ne 1 && BUG "1 param" - if ! test -d "$1" + if ! test -d "$@" then - echo "Directory $1 doesn't exist" - false + echo "Directory $* doesn't exist" + return 1 fi } test_path_exists () { - test "$#" -ne 1 && BUG "1 param" - if ! test -e "$1" + if ! test -e "$@" then - echo "Path $1 doesn't exist" - false + echo "Path $* doesn't exist" + return 1 fi } # Check if the directory exists and is empty as expected, barf otherwise. test_dir_is_empty () { - test "$#" -ne 1 && BUG "1 param" - test_path_is_dir "$1" && - if test -n "$(ls -a1 "$1" | egrep -v '^\.\.?$')" + test_path_is_dir "$@" && + if test -n "$(ls -a1 "$@" | egrep -v '^\.\.?$')" then - echo "Directory '$1' is not empty, it contains:" + echo "Directory '$*' is not empty, it contains:" ls -la "$1" return 1 fi @@ -798,19 +800,17 @@ test_dir_is_empty () { # Check if the file exists and has a size greater than zero test_file_not_empty () { - test "$#" = 2 && BUG "2 param" - if ! test -s "$1" + if ! test -s "$@" then - echo "'$1' is not a non-empty file." - false + echo "'$*' is not a non-empty file." + return 1 fi } test_path_is_missing () { - test "$#" -ne 1 && BUG "1 param" - if test -e "$1" + if test -e "$@" then - echo "Path $1 exists!" + echo "Path $* exists!" false fi } @@ -1012,7 +1012,6 @@ test_expect_code () { # - not all diff versions understand "-u" test_cmp () { - test "$#" -ne 2 && BUG "2 param" eval "$GIT_TEST_CMP" '"$@"' } @@ -1042,7 +1041,6 @@ test_cmp_config () { # test_cmp_bin - helper to compare binary files test_cmp_bin () { - test "$#" -ne 2 && BUG "2 param" cmp "$@" } @@ -1096,12 +1094,11 @@ verbose () { # otherwise. test_must_be_empty () { - test "$#" -ne 1 && BUG "1 param" - test_path_is_file "$1" && - if test -s "$1" + test_path_is_file "$@" && + if test -s "$@" then - echo "'$1' is not empty, it contains:" - cat "$1" + echo "'$*' is not empty, it contains:" + cat "$@" return 1 fi }
This reverts and amends my my own e7884b353b7 (test-lib-functions: assert correct parameter count, 2021-02-12) in order to improve the -x output. The goal here is to get rid of the verbosity of having e.g. a "test 2 -ne 2" line for every "test_cmp". We use "$@" as an argument to "test" to intentionally feed the "test" operator too many arguments if the functions are called with too many arguments, thus piggy-backing on it to check the number of arguments we get. Before this for each test_cmp invocation we'd emit: + test_cmp expect actual + test 2 -ne 2 + eval diff -u "$@" + diff -u expect actual That "test 2 -ne 2" line is new in my e7884b353b7. As noted in 45a2686441b (test-lib-functions: remove bug-inducing "diagnostics" helper param, 2021-02-12) we had buggy invocations of some of these functions with too many parameters. Now we'll get just: + test_cmp expect actual + eval diff -u "$@" + diff -u expect actual This does not to the "right" thing in cases like: test_path_is_file x -a y Which will now turn into: test -f x -a y I consider that to be OK given the trade-off that any extra checking would produce more verbose trace output. As shown in 45a2686441b we had issues with these functions being invoked with multiple parameters (e.g. a glob) by accident, we don't need to be paranoid in guarding against hostile misuse from our own test suite. While I'm at it change a few functions that relied on a "false" being the last statement in the function to use an explicit "return 1" like the other functions in this file. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> --- t/test-lib-functions.sh | 59 +++++++++++++++++++---------------------- 1 file changed, 28 insertions(+), 31 deletions(-)