hook: don't crash on syntax errors in python hooks We had some real-world cases where syntax errors in Python hooks would crash the whole process and leave it in an indeterminate state. Handle those better.

hook: for python hook exceptions, add note to run with --traceback Just like with ImportErrors, it isn't obvious that --traceback will produce helpful debugging output here.

hook: add tests for failing post- python hooks I couldn't find any tests for this.

hook: even fewer parentheses for load errors Missed this one.

destutil: document various failure cases We document what various conditional branch mean and clarify that they are exclusive (since they all end up in with exception raised).

destutil: consistently retrieve 'p1' and 'branch' We already read p1 from the dirstate so let's read the branch from it too.

merge: give priority to "not at head" failures for bare 'hg merge' We refuse to pick a destination for a bare 'hg merge' if the working copy is not at head. This is meant to prevent strange merge from user who forget to update. (Moreover, such merge does not reduce actually the number of heads) However, we were doing that as the last possible failure type. So user were recommended to merge with an explicit head (from this bad location) if the branch had too many heads. We now make "not on branch heads" class of failure the first things to check and fail on. The one test that change was actually trying to check for these failure (and did not). The new test output is correct.

destutil: extract all 'mergedest' abort messages into a dictionary We plan to be able to reuse this function for rebase. The error message explicitly refers to "merge" in multiple places. So we'll need to be able to use different messages. The first step of that is to extract all messages in a dedicated dictionary and use them indirectly. As a side effect it clarifies the actual function and opens the way to various cleanups and fixes in future changesets.

tests: add an explicit destination in some rebase tests As we will make 'rebase' behave more like 'merge', it will no longer pick 'max(branch(.))' as the default destination. We have to hard code the expected destination is multiple tests where it matters. After a careful inspection none of theses tests really cares about the default destination behavior and just omitted one out of laziness.

tests: remove third head in some of the 'rebase-parameters' tests These tests do not care about that extra branch at all. In future changeset we will make rebase behave like merge and abort in case of an ambiguous destination (eg: multiple other heads) and that extra branch will make the command invocation breaks. We preventively remove this extra branch from the relevant tests in an independant changeset to reduce noise and increase confidence in the final change.

run-tests: allow to specify executable of any name by --with-hg If the executable is not named as "hg", TTest runner inserts alias. This way, we can run tests with chg. But it is still warned because the alias does not always work. We do "$BINDIR"/hg in a few places.

run-tests: drop redundant assignment to BINDIR We do it a few lines after.

run-tests: cast --with-hg option to bytes consistently at parseargs() parseargs() sets bytes to options.with_hg if --local is specified, so do the same for --with-hg.

run-tests: do not compare bytes with str while ordering tests It failed on Python 3.

clonebundles: use absolute_import

churn: use absolute_import

children: use absolute_import

censor: use absolute_import

bugzilla: use absolute_import

blackbox: use absolute_import

acl: use absolute_import Continuing the march towards Python 3.

checkunknown: audit path before checking if it's a file or link Previously we would lstat the file to see if it was a file or a link before attempting to process it. If the file happened to exist across a symlink, and if that symlink was pointing to a network file system, that check could be very expensive. The new logic audit's the path to avoid symlinks before performing the lstat on the file itself. In our situation, this shaved 10 minutes off of certain hg updates. 300 files * (2 seconds - the network filesystem lookup time)

pathauditor: change parts verification order to be root first Previously, when we verified the parts of a path in the auditor, we would validate the deepest directory first, then it's parent, and so on up to the root. If there happened to be a symlink in the chain, that meant our first check would likely traverse that symlink. In some cases that symlink might point to a network filesystem that is expensive, and therefore this simple check could be very slow. The fix is to check the path parts starting at the root and working our way down. This has a minor performance difference in that we used to be able to short circuit from the audit if we reached a directory that had already been checked. Now we can't, but the cost is N dictionary look ups, where N is the number of parts in the path, which should be fairly minor.

chg: forward job control signals to worker process (issue5051) This is necessary to suspend/resume long pulls, interactive curses session, etc. The implementation is based on emacsclient, but our version doesn't test if chg process is foreground or not before propagating SIGCONT. This is because chg isn't always an interactive session. If we copy the SIGTTIN/SIGTTOU emulation from emacsclient, non-interactive session can't be moved to a background job. $ chg pull ^Z suspended $ bg %1 [1] continued [1] suspended (tty input) # wrong https://github.com/emacs-mirror/emacs/blob/0e96320/lib-src/emacsclient.c#L1094

chg: verify return value of sigaction() and sigemptyset() They should never fail, but it couldn't hurt to be a paranoid.

chg: initialize sigaction fields more reliably It seems calling memset() and sigemptyset() is common pattern to initialize sigaction. And strictly speaking, sigset_t must be initialized by sigemptyset() or sigfillset(). I saw git and uwsgi do that way, so let's follow them.

tests: confirm that a badly documented extension doesn't cause a crash An external extension whose docstring doesn't conform to Mercurial standards used to cause crashes. Test that we omit such extensions when you do a keyword search.

bookmarks: avoid creating a nested repository during testing This helps the test to pass with hgwatchman, which would otherwise need to be taught about a nested .hg directory. hgwatchman already blacklists test-nested-repo.t which covers the actual usecase

dispatch: strip command line options like config file options Currently, whitespace in command line --config options are considered significant while whitespace in config files are not considered significant. This diff strips the leading and trailing whitespace from command line config options.

hook: for python hook ImportErrors, add note to run with --traceback I personally found it completely non-obvious that --traceback prints out stack traces for failed imports.