From 89cd24937e1b0dd183082b1bbc05d0a67f33ad98 Mon Sep 17 00:00:00 2001 From: alisdair sullivan Date: Tue, 20 May 2014 06:35:40 +0000 Subject: improve behaviour of `rebar shell` attempt to emulate the behavior of `erl -pa ebin -pa deps/*/ebin` fix error messages and formatting issues of `rebar shell` by shutting down and restarting the user subsystem in a mode more hospitable to the shell than the simple user started when run as an escript. emulate `error_logger` behaviour when the shell is run via `erl` add documentation of the shell command limitations: the erlang interrupt handler is not enabled when running as an escript and there is no interface to re-enable it via erlang code. this means `ctrl-c` will immediately exit the running process unlike when running the shell via `erl`. `ctrl-g` is, however, unaffected the user subsystem is killed and restarted but not supervised. if your code somehow relies on the user subsystem crashing and restarting `rebar shell` may interfere with it's operation --- src/rebar.erl | 3 +++ src/rebar_shell.erl | 55 +++++++++++++++++++++++++++++++++-------------------- 2 files changed, 37 insertions(+), 21 deletions(-) (limited to 'src') diff --git a/src/rebar.erl b/src/rebar.erl index d5d6c77..a43da5f 100644 --- a/src/rebar.erl +++ b/src/rebar.erl @@ -409,6 +409,9 @@ qc Test QuickCheck properties xref Run cross reference analysis +shell Start a shell similar to + 'erl -pa ebin -pa deps/*/ebin' + help Show the program options version Show version information ">>, diff --git a/src/rebar_shell.erl b/src/rebar_shell.erl index 2dbf4a0..348e540 100644 --- a/src/rebar_shell.erl +++ b/src/rebar_shell.erl @@ -30,27 +30,40 @@ -include("rebar.hrl"). --export([shell/2]). +-export([shell/2, info/2]). + +%% NOTE: +%% this is an attempt to replicate `erl -pa ./ebin -pa deps/*/ebin`. it is +%% mostly successful but does stop and then restart the user io system to get +%% around issues with rebar being an escript and starting in `noshell` mode. +%% it also lacks the ctrl-c interrupt handler that `erl` features. ctrl-c will +%% immediately kill the script. ctrl-g, however, works fine shell(_Config, _AppFile) -> - ?CONSOLE("NOTICE: Using experimental 'shell' command~n", []), - %% backwards way to say we only want this executed - %% for the "top level" directory - case is_deps_dir(rebar_utils:get_cwd()) of - false -> - true = code:add_pathz(rebar_utils:ebin_dir()), - user_drv:start(), - %% this call never returns (until user quits shell) - shell:server(false, false); - true -> - ok - end, - ok. + true = code:add_pathz(rebar_utils:ebin_dir()), + %% terminate the current user + ok = supervisor:terminate_child(kernel_sup, user), + %% start a new shell (this also starts a new user under the correct group) + user_drv:start(), + %% enable error_logger's tty output + ok = error_logger:swap_handler(tty), + %% disable the simple error_logger (which may have been added multiple + %% times). removes at most the error_logger added by init and the + %% error_logger added by the tty handler + ok = remove_error_handler(3), + %% this call never returns (until user quits shell) + timer:sleep(infinity). + +info(help, shell) -> + ?CONSOLE( + "Start a shell with project and deps preloaded similar to~n" + "'erl -pa ebin -pa deps/*/ebin'.~n", + []). -is_deps_dir(Dir) -> - case lists:reverse(filename:split(Dir)) of - [_, "deps" | _] -> - true; - _V -> - false - end. +remove_error_handler(0) -> + ?WARN("Unable to remove simple error_logger handler~n", []); +remove_error_handler(N) -> + case gen_event:delete_handler(error_logger, error_logger, []) of + {error, module_not_found} -> ok; + {error_logger, _} -> remove_error_handler(N-1) + end. \ No newline at end of file -- cgit v1.1