worker: rewrite error handling so os._exit covers all cases Previously the worker error handling is like: pid = os.fork() --+ if pid == 0: | .... | problematic .... --+ try: --+ .... | worker error handling --+ If a signal arrives when Python is executing the "problematic" lines, an external error handling (dispatch.py) will take over the control flow and it's no longer guaranteed "os._exit" is called (see 86cd09bc13ba for why it is necessary). This patch rewrites the error handling so it covers all possible code paths for a worker even during fork. Note: "os.getpid() == parentpid" is used to test if the process is parent or not intentionally, instead of checking "pid", because "pid = os.fork()" may be not atomic - it's possible that that a signal hits the worker before the assignment completes [1]. The newly added test replaces "os.fork" to exercise that extreme case. [1]: CPython compiles "pid = os.fork()" to 2 byte codes: "CALL_FUNCTION" and "STORE_FAST", so it's probably not atomic: def f(): pid = os.fork() dis.dis(f) 2 0 LOAD_GLOBAL 0 (os) 3 LOAD_ATTR 1 (fork) 6 CALL_FUNCTION 0 9 STORE_FAST 0 (pid) 12 LOAD_CONST 0 (None) 15 RETURN_VALUE

dispatch: take over SignalInterrupt handling from scmutil dispatch handles KeyboardInterrupt already. This makes the code more consistent, and makes worker not print "killed!" if it receives SIGTERM in most cases (in rare cases there is still "killed!" printed, which will be fixed by the next patch).

merge stable into default

Added signature for changeset bb96d4a49743

Added tag 4.2 for changeset bb96d4a49743

merge with i18n

i18n-ja: synchronized with 6e0368b6e0bb

pager: drop the support for 'pager.enable=<bool>' This option was never released except for a release candidate. Dropping compatibility with this option will free the 'pager.enable' config option for other usage in the future.

pager: rename 'pager.enable' to 'ui.paginate' This aligns with what we do for color (see 7fec37746417). Pager is a central enough notion that having the master config in the [ui] section makes senses. It will helps with consistency, discoverability. It will also help having a simple and clear example hgrc mentioning pager. The previous form of the option had never been released in a non-rc version but we keep it around for convenience. If both are set, 'ui.pager' take priority.

color: special case 'always' in 'ui.color' This lift the confusing case, where 'ui.color=always' would actually not always use color.

color: turn 'ui.color' into a boolean (auto or off) Previously, 'ui.color=yes' meant "always show color", While "ui.color=auto" meant "use color automatically when it appears sensible". This feels problematic to some people because if an administrator has disabled color with "ui.color=off", and a user turn it back on using "color=on", it will get surprised (because it breaks their output when redirected to a file.) This patch changes ui.color=true to only move the default value of --color from "never" to "auto". I'm not really in favor of this changes as I suspect the above case will be pretty rare and I would rather keep the logic simpler. However, I'm providing this patch to help the 4.2 release in the case were others decide to make this changes. Users that want to force colors without specifying --color on the command line can use the 'ui.formatted' config knob, which had to be enabled in a handful of tests for this patch. Nice summary table (credit: Augie Fackler) That is, before this patch: +--------------------+--------------------+--------------------+ | | not a tty | a tty | | | --color not set | --color not set | | | | | +--------------------+--------------------+--------------------+ | [ui] | | | | color (not set) | no color | no color | | | | | +--------------------+--------------------+--------------------+ | [ui] | | | | color = auto | no color | color | | | | | +--------------------+--------------------+--------------------+ | [ui] | | | | color = yes | *color* | color | | | | | +--------------------+--------------------+--------------------+ | [ui] | | | | color = no | no color | no color | | | | | +--------------------+--------------------+--------------------+ (if --color is specified, it always clobbers the setting in [ui]) and after this patch: +--------------------+--------------------+--------------------+ | | not a tty | a tty | | | --color not set | --color not set | | | | | +--------------------+--------------------+--------------------+ | [ui] | | | | color (not set) | no color | no color | | | | | +--------------------+--------------------+--------------------+ | [ui] | | | | color = auto | no color | color | | | | | +--------------------+--------------------+--------------------+ | [ui] | | | | color = yes | *no color* | color | | | | | +--------------------+--------------------+--------------------+ | [ui] | | | | color = no | no color | no color | | | | | +--------------------+--------------------+--------------------+ (if --color is specified, it always clobbers the setting in [ui])

pager: document the 'pager.enable' option The 'config' helps was missing help about pager enabling/disabling.

pager: advertise the config option in the default hgrc Same as for 'ui.color', this is a critical part of the UI and we want user to find this config knob easily.

pager: document the 'pager' config section There as a 'hg help pager' section but the 'hg help config.pager' was missing.

pager: test the 'enable' config option While poking at this option I realised it was not tested.

config: drop pager from the recommended extension The extension is deprecated, we should having exposing it to users.