rebar3WithPlugins: add ability to ignore dependencies

pkgs/development/beam-modules/rebar3-release.nix

···
 
     inherit src;
 
+    REBAR_IGNORE_DEPS = beamDeps != [ ];
+
     configurePhase = ''
       runHook preConfigure
       ${lib.optionalString (checkouts != null)
       "cp --no-preserve=all -R ${checkouts}/_checkouts ."}
-      ${# Prevent rebar3 from trying to manage deps
-      lib.optionalString (beamDeps != [ ]) ''
-        erl -noshell -eval '
-          {ok, Terms0} = file:consult("rebar.config"),
-          Terms = lists:keydelete(deps, 1, Terms0),
-          ok = file:write_file("rebar.config", [io_lib:format("~tp.~n", [T]) || T <- Terms]),
-          init:stop(0)
-        '
-        rm -f rebar.lock
-      ''}
       runHook postConfigure
     '';
 

pkgs/development/tools/build-managers/rebar3/default.nix

···
           {ok, _} = zip:extract(Archive, [{cwd, "'$out/lib'"}]),
           init:stop(0)
         '
+        cp ${./rebar_ignore_deps.erl} rebar_ignore_deps.erl
+        erlc -o $out/lib/rebar/ebin rebar_ignore_deps.erl
         mkdir -p $out/bin
         makeWrapper ${erlang}/bin/erl $out/bin/rebar3 \
-          --set REBAR_GLOBAL_PLUGINS "${toString globalPluginNames}" \
+          --set REBAR_GLOBAL_PLUGINS "${toString globalPluginNames} rebar_ignore_deps" \
           --suffix-each ERL_LIBS ":" "$out/lib ${toString pluginLibDirs}" \
           --add-flags "+sbtu +A1 -noshell -boot start_clean -s rebar3 main -extra"
       '';

pkgs/development/tools/build-managers/rebar3/rebar_ignore_deps.erl

···
+%% This module, when loaded as a plugin, overrides the default `install_deps`
+%% provider and erases the dependencies from the rebar3 state, when
+%% REBAR_IGNORE_DEPS is true.
+
+-module(rebar_ignore_deps).
+
+-export([init/1, do/1, format_error/1]).
+
+init(State0) ->
+    case os:getenv("REBAR_IGNORE_DEPS", "") of
+        "" ->
+            {ok, State0};
+        _ ->
+            do_init(State0)
+    end.
+
+do_init(State0) ->
+    State1 = rebar_state:allow_provider_overrides(State0, true),
+    Provider = providers:create(
+                 [
+                  {name, install_deps}, %% override the default install_deps provider
+                  {module, ?MODULE},
+                  {bare, false},
+                  {deps, [app_discovery]},
+                  {example, undefined},
+                  {opts, []},
+                  {short_desc, ""},
+                  {desc, ""}
+                 ]),
+    State2 = rebar_state:add_provider(State1, Provider),
+    {ok, rebar_state:allow_provider_overrides(State2, false)}.
+
+do(State0) ->
+    io:format("Ignoring deps...~n"),
+    Profiles = rebar_state:current_profiles(State0),
+    State = lists:foldl(fun(P, Acc0) ->
+                                 Acc = rebar_state:set(Acc0, {deps, P}, []),
+                                 rebar_state:set(Acc, {parsed_deps, P}, [])
+                         end, State0, Profiles),
+    {ok, State}.
+
+format_error(Reason) ->
+    io_lib:format("~p", [Reason]).