install project app plugins after discovering them not before

src/rebar3.erl

@@ -123,7 +123,7 @@ run_aux(State, RawArgs) ->
     {ok, Providers} = application:get_env(rebar, providers),
     %% Providers can modify profiles stored in opts, so set default after initializing providers
     State5 = rebar_state:create_logic_providers(Providers, State4),
-    State6 = rebar_plugins:project_apps_install(State5),
+    State6 = rebar_plugins:top_level_install(State5),
     State7 = rebar_state:default(State6, rebar_state:opts(State6)),
 
     {Task, Args} = parse_args(RawArgs),

src/rebar_plugins.erl

@@ -3,7 +3,8 @@
 
 -module(rebar_plugins).
 
--export([project_apps_install/1
+-export([top_level_install/1
+        ,project_apps_install/1
         ,install/2
         ,handle_plugins/3
         ,handle_plugins/4]).
@@ -14,11 +15,18 @@
 %% Public API
 %% ===================================================================
 
+-spec top_level_install(rebar_state:t()) -> rebar_state:t().
+top_level_install(State) ->
+    Profiles = rebar_state:current_profiles(State),
+    lists:foldl(fun(Profile, StateAcc) ->
+                        Plugins = rebar_state:get(State, {plugins, Profile}, []),
+                        handle_plugins(Profile, Plugins, StateAcc)
+                end, State, Profiles).
+
 -spec project_apps_install(rebar_state:t()) -> rebar_state:t().
 project_apps_install(State) ->
     Profiles = rebar_state:current_profiles(State),
     ProjectApps = rebar_state:project_apps(State),
-
     lists:foldl(fun(Profile, StateAcc) ->
                         Plugins = rebar_state:get(State, {plugins, Profile}, []),
                         StateAcc1 = handle_plugins(Profile, Plugins, StateAcc),

src/rebar_prv_app_discovery.erl

@@ -36,7 +36,8 @@ do(State) ->
     LibDirs = rebar_dir:lib_dirs(State),
     try
         State1 = rebar_app_discover:do(State, LibDirs),
-        {ok, State1}
+        State2 = rebar_plugins:project_apps_install(State1),
+        {ok, State2}
     catch
         throw:{error, {rebar_packages, Error}} ->
             {error, {rebar_packages, Error}};

test/rebar_plugins_SUITE.erl

@@ -10,7 +10,8 @@
          compile_global_plugins/1,
          complex_plugins/1,
          list/1,
-         upgrade/1]).
+         upgrade/1,
+         sub_app_plugins/1]).
 
 -include_lib("common_test/include/ct.hrl").
 -include_lib("eunit/include/eunit.hrl").
@@ -32,7 +33,7 @@ end_per_testcase(_, _Config) ->
     catch meck:unload().
 
 all() ->
-    [compile_plugins, compile_global_plugins, complex_plugins, list, upgrade].
+    [compile_plugins, compile_global_plugins, complex_plugins, list, upgrade, sub_app_plugins].
 
 %% Tests that compiling a project installs and compiles the plugins of deps
 compile_plugins(Config) ->
@@ -208,3 +209,34 @@ upgrade(Config) ->
         Config, RConf, ["plugins", "upgrade", PkgName],
         {ok, [{app, Name}, {plugin, PkgName, <<"0.1.3">>}]}
      ).
+
+sub_app_plugins(Config) ->
+    AppDir = ?config(apps, Config),
+
+    Name = rebar_test_utils:create_random_name("sub_app1_"),
+    Vsn = rebar_test_utils:create_random_vsn(),
+
+    DepName = rebar_test_utils:create_random_name("dep1_"),
+    PluginName = rebar_test_utils:create_random_name("plugin1_"),
+
+    mock_pkg_resource:mock([{pkgdeps, [{{list_to_binary(DepName), list_to_binary(Vsn)}, []},
+                                       {{list_to_binary(PluginName), list_to_binary(Vsn)}, []}]}]),
+
+    SubAppsDir = filename:join([AppDir, "apps", Name]),
+
+    rebar_test_utils:create_app(SubAppsDir, Name, Vsn, [kernel, stdlib]),
+    rebar_test_utils:create_config(SubAppsDir, [{deps, [{list_to_binary(DepName), list_to_binary(Vsn)}]},
+                                                {plugins, [list_to_atom(PluginName)]}]),
+
+    RConfFile =
+        rebar_test_utils:create_config(AppDir,
+                                       [{deps, [
+                                               list_to_atom(DepName)
+                                               ]}]),
+    {ok, RConf} = file:consult(RConfFile),
+
+    %% Build with deps.
+    rebar_test_utils:run_and_check(
+      Config, RConf, ["compile"],
+      {ok, [{app, Name}, {dep, DepName}, {plugin, PluginName}]}
+     ).