Message ID | 328b5d6e76f598590d24b35ec23b5fd854c6cf05.1630503102.git.gitgitgadget@gmail.com (mailing list archive) |
---|---|
State | Superseded |
Headers | show |
Series | test-lib-functions.sh: keep user's HOME, TERM and SHELL for 'test_pause' and 'debug' | expand |
"Philippe Blain via GitGitGadget" <gitgitgadget@gmail.com> writes: > +# Usage: test_pause [options] > +# -t > +# Use your original TERM instead of test-lib.sh's "dumb". > +# This usually restores color output in the invoked shell. > +# WARNING: this can break test reproducibility. > +# -s > +# Invoke $SHELL instead of $TEST_SHELL_PATH > +# WARNING: this can break test reproducibility. > +# -h > +# Use your original HOME instead of test-lib.sh's "$TRASH_DIRECTORY". > +# This allows you to use your regular shell environment and Git aliases. > +# WARNING: this can break test reproducibility. > +# CAUTION: this can overwrite files in your HOME. > +# -a > +# Shortcut for -t -s -h As this is not end-user facing but facing our developer, I do not deeply care, but I find the warnings in this help text problematic. Because a new process instance of $PAUSE_SHELL is run, the options you add when inserting test_pause does not affect what happens in the tests after you exit the $PAUSE_SHELL [*], right? Of course, you can modify the repository or the working tree files used in the test in the $PAUSE_SHELL, and that can break "test reproducibility"---if you run "git ls-files -s" and take its output in a temporary file, a step later in the test that runs "git status" will see an extra untracked file, for example, and such a change may (or may not) unnecessarily break the tests. But it is not anything new introduced by these options. It is inherent to test_pause itself. If we want to add a warning to the help text here, I think it should be written in such a way that it is clear that the warning applies to any use of the test_pause helper, not just to the form with the options. Thanks. [Footnote] * If we had an alternative implementation of test_pause that does not use a separate $PAUSE_SHELL process, but instead like inserting a read-eval-print loop, that would be far more powerful and useful debugging aid. You can not just stop the execution of the test, and observe the files in the test repository and the environment variables---you can also access shell variables and functions. Such a test_pause from another world would deserve a "if you touch anything, the damage is permanent" warning even more than the current one, because you can modify even a shell variable to affect the execution of the test after you leave the paused state.
On Wed, Sep 1, 2021 at 1:26 PM Junio C Hamano <gitster@pobox.com> wrote: > > "Philippe Blain via GitGitGadget" <gitgitgadget@gmail.com> writes: > > > +# Usage: test_pause [options] > > +# -t > > +# Use your original TERM instead of test-lib.sh's "dumb". > > +# This usually restores color output in the invoked shell. > > +# WARNING: this can break test reproducibility. > > +# -s > > +# Invoke $SHELL instead of $TEST_SHELL_PATH > > +# WARNING: this can break test reproducibility. > > +# -h > > +# Use your original HOME instead of test-lib.sh's "$TRASH_DIRECTORY". > > +# This allows you to use your regular shell environment and Git aliases. > > +# WARNING: this can break test reproducibility. > > +# CAUTION: this can overwrite files in your HOME. > > +# -a > > +# Shortcut for -t -s -h > > As this is not end-user facing but facing our developer, I do not > deeply care, but I find the warnings in this help text problematic. > > Because a new process instance of $PAUSE_SHELL is run, the options > you add when inserting test_pause does not affect what happens in > the tests after you exit the $PAUSE_SHELL [*], right? I think the warning was less about what happens after test_pause is complete and the testcase resumes, and more intended to convey that if the user tries to manually copy & paste snippets of code from the test into $PAUSE_SHELL, then the use of these flags can cause the result of those pasted commands to differ. If so, a small rewording might be in order, e.g. "WARNING: this can cause commands run in the paused shell to give different results". I'd also say the CAUTION would perhaps benefit from some rewording (since the option itself doesn't cause files to be overwritten), e.g. "CAUTION: using this option and copying commands from the test script into the paused shell might result in files in your HOME being overwritten". > Of course, you can modify the repository or the working tree files > used in the test in the $PAUSE_SHELL, and that can break "test > reproducibility"---if you run "git ls-files -s" and take its output > in a temporary file, a step later in the test that runs "git status" > will see an extra untracked file, for example, and such a change may > (or may not) unnecessarily break the tests. > > But it is not anything new introduced by these options. It is > inherent to test_pause itself. > > If we want to add a warning to the help text here, I think it should > be written in such a way that it is clear that the warning applies > to any use of the test_pause helper, not just to the form with the > options. > > Thanks. > > > [Footnote] > > * If we had an alternative implementation of test_pause that does > not use a separate $PAUSE_SHELL process, but instead like > inserting a read-eval-print loop, that would be far more powerful > and useful debugging aid. You can not just stop the execution of > the test, and observe the files in the test repository and the > environment variables---you can also access shell variables and > functions. > > Such a test_pause from another world would deserve a "if you touch > anything, the damage is permanent" warning even more than the > current one, because you can modify even a shell variable to > affect the execution of the test after you leave the paused state.
Elijah Newren <newren@gmail.com> writes: >> Because a new process instance of $PAUSE_SHELL is run, the options >> you add when inserting test_pause does not affect what happens in >> the tests after you exit the $PAUSE_SHELL [*], right? > > I think the warning was less about what happens after test_pause is > complete and the testcase resumes, and more intended to convey that if > the user tries to manually copy & paste snippets of code from the test > into $PAUSE_SHELL, then the use of these flags can cause the result of > those pasted commands to differ. But the difference of TERM and SHELL are much smaller issue when one cuts and pastes the lines from the test script. Even if you do not use -s or -t options, shell variables and helpers won't be available to the interactive session given by test_pause, and that is a much bigger difference between the "real" shell environment that is running the tests and the user's shell environment test_pause gives us. That is why I think the WARNING should be attached _directly_ to the description of test_pause and not to individual "this uses different X environment compared to the real shell environment running the tests" options. The updated $HOME does deserve a special mention, as .gitconfig from it would further affect the tests and hide the bug you are hunting for, and the CAUTION is a good thing to have, even if you do not plan to modify anything in the test_pause sight-seeing session.
Hi Elijah and Junio, Le 2021-09-01 à 19:09, Junio C Hamano a écrit : > Elijah Newren <newren@gmail.com> writes: > >>> Because a new process instance of $PAUSE_SHELL is run, the options >>> you add when inserting test_pause does not affect what happens in >>> the tests after you exit the $PAUSE_SHELL [*], right? >> >> I think the warning was less about what happens after test_pause is >> complete and the testcase resumes, and more intended to convey that if >> the user tries to manually copy & paste snippets of code from the test >> into $PAUSE_SHELL, then the use of these flags can cause the result of >> those pasted commands to differ. Yes, I added the warnings based on the reticence I got in v1 to change the behaviour without adding flags. > > But the difference of TERM and SHELL are much smaller issue when one > cuts and pastes the lines from the test script. Even if you do not > use -s or -t options, shell variables and helpers won't be available > to the interactive session given by test_pause, and that is a much > bigger difference between the "real" shell environment that is > running the tests and the user's shell environment test_pause gives > us. That is why I think the WARNING should be attached _directly_ > to the description of test_pause and not to individual "this uses > different X environment compared to the real shell environment > running the tests" options. OK, I can make that tweak. Le 2021-09-01 à 17:52, Elijah Newren a écrit : -- snip -- > those pasted commands to differ. If so, a small rewording might be in > order, e.g. "WARNING: this can cause commands run in the paused shell > to give different results". I'd also say the CAUTION would perhaps > benefit from some rewording (since the option itself doesn't cause > files to be overwritten), e.g. "CAUTION: using this option and copying > commands from the test script into the paused shell might result in > files in your HOME being overwritten". Thanks for these suggestions, that wording does seem clearer. Philippe.
diff --git a/t/test-lib-functions.sh b/t/test-lib-functions.sh index 1884177e293..4b667dc7e76 100644 --- a/t/test-lib-functions.sh +++ b/t/test-lib-functions.sh @@ -137,9 +137,51 @@ test_tick () { # Stop execution and start a shell. This is useful for debugging tests. # # Be sure to remove all invocations of this command before submitting. +# +# Usage: test_pause [options] +# -t +# Use your original TERM instead of test-lib.sh's "dumb". +# This usually restores color output in the invoked shell. +# WARNING: this can break test reproducibility. +# -s +# Invoke $SHELL instead of $TEST_SHELL_PATH +# WARNING: this can break test reproducibility. +# -h +# Use your original HOME instead of test-lib.sh's "$TRASH_DIRECTORY". +# This allows you to use your regular shell environment and Git aliases. +# WARNING: this can break test reproducibility. +# CAUTION: this can overwrite files in your HOME. +# -a +# Shortcut for -t -s -h test_pause () { - "$TEST_SHELL_PATH" <&6 >&5 2>&7 + PAUSE_TERM=$TERM && + PAUSE_SHELL=$TEST_SHELL_PATH && + PAUSE_HOME=$HOME && + while test $# != 0 + do + case "$1" in + -t) + PAUSE_TERM="$USER_TERM" + ;; + -s) + PAUSE_SHELL="$SHELL" + ;; + -h) + PAUSE_HOME="$USER_HOME" + ;; + -a) + PAUSE_TERM="$USER_TERM" + PAUSE_SHELL="$SHELL" + PAUSE_HOME="$USER_HOME" + ;; + *) + break + ;; + esac + shift + done && + TERM="$PAUSE_TERM" HOME="$PAUSE_HOME" "$PAUSE_SHELL" <&6 >&5 2>&7 } # Wrap git with a debugger. Adding this to a command can make it easier diff --git a/t/test-lib.sh b/t/test-lib.sh index abcfbed6d61..132618991e2 100644 --- a/t/test-lib.sh +++ b/t/test-lib.sh @@ -585,8 +585,9 @@ else } fi +USER_TERM="$TERM" TERM=dumb -export TERM +export TERM USER_TERM error () { say_color error "error: $*" @@ -1380,9 +1381,10 @@ then fi # Last-minute variable setup +USER_HOME="$HOME" HOME="$TRASH_DIRECTORY" GNUPGHOME="$HOME/gnupg-home-not-used" -export HOME GNUPGHOME +export HOME GNUPGHOME USER_HOME # Test repository rm -fr "$TRASH_DIRECTORY" || {