Merge pull request #1596 from ferd/local-apps-override-deps

Allow top-level apps to take precedence over deps

src/rebar_app_utils.erl

@@ -34,6 +34,7 @@
          validate_application_info/2,
          parse_deps/5,
          parse_deps/6,
+         expand_deps_sources/2,
          dep_to_app/7,
          format_error/1]).
 
@@ -227,7 +228,7 @@ dep_to_app(Parent, DepsDir, Name, Vsn, Source, IsLock, State) ->
                                     not_found ->
                                         rebar_app_info:new(Parent, Name, Vsn, Dir, [])
                                 end,
-                                update_source(AppInfo0, Source, State)
+                                rebar_app_info:source(AppInfo0, Source)
                     end,
     C = rebar_config:consult(rebar_app_info:dir(AppInfo)),
     AppInfo1 = rebar_app_info:update_opts(AppInfo, rebar_app_info:opts(AppInfo), C),
@@ -238,6 +239,13 @@ dep_to_app(Parent, DepsDir, Name, Vsn, Source, IsLock, State) ->
     AppInfo5 = rebar_app_info:profiles(AppInfo4, [default]),
     rebar_app_info:is_lock(AppInfo5, IsLock).
 
+%% @doc Takes a given application app_info record along with the project.
+%% If the app is a package, resolve and expand the package definition.
+-spec expand_deps_sources(rebar_app_info:t(), rebar_state:t()) ->
+    rebar_app_info:t().
+expand_deps_sources(Dep, State) ->
+    update_source(Dep, rebar_app_info:source(Dep), State).
+
 %% @doc sets the source for a given dependency or app along with metadata
 %% around version if required.
 -spec update_source(rebar_app_info:t(), Source, rebar_state:t()) ->

src/rebar_prv_install_deps.erl

@@ -140,7 +140,9 @@ handle_deps_as_profile(Profile, State, Deps, Upgrade) ->
     DepsDir = profile_dep_dir(State, Profile),
     Deps1 = rebar_app_utils:parse_deps(DepsDir, Deps, State, Locks, Level),
     ProfileLevelDeps = [{Profile, Deps1, Level}],
-    handle_profile_level(ProfileLevelDeps, [], sets:new(), Upgrade, Locks, State).
+    RootSeen = sets:from_list([rebar_app_info:name(AppInfo)
+                               || AppInfo <- rebar_state:project_apps(State)]),
+    handle_profile_level(ProfileLevelDeps, [], RootSeen, RootSeen, Upgrade, Locks, State).
 
 %% ===================================================================
 %% Internal functions
@@ -153,7 +155,9 @@ deps_per_profile(Profiles, Upgrade, State) ->
     Deps = lists:foldl(fun(Profile, DepAcc) ->
                                [parsed_profile_deps(State, Profile, Level) | DepAcc]
                        end, [], Profiles),
-    handle_profile_level(Deps, [], sets:new(), Upgrade, Locks, State).
+    RootSeen = sets:from_list([rebar_app_info:name(AppInfo)
+                               || AppInfo <- rebar_state:project_apps(State)]),
+    handle_profile_level(Deps, [], RootSeen, RootSeen, Upgrade, Locks, State).
 
 parsed_profile_deps(State, Profile, Level) ->
     ParsedDeps = rebar_state:get(State, {parsed_deps, Profile}, []),
@@ -162,17 +166,27 @@ parsed_profile_deps(State, Profile, Level) ->
 %% Level-order traversal of all dependencies, across profiles.
 %% If profiles x,y,z are present, then the traversal will go:
 %% x0, y0, z0, x1, y1, z1, ..., xN, yN, zN.
-handle_profile_level([], Apps, _Seen, _Upgrade, _Locks, State) ->
+%%
+%% There are two 'seen' sets: one for the top-level apps (`RootSeen') and
+%% one for all dependencies (`Seen'). The former is used to know when
+%% to skip the resolving of dependencies altogether (since they're already
+%% top-level apps), while the latter is used to prevent reprocessing
+%% deps more than one.
+handle_profile_level([], Apps, _RootSeen, _Seen, _Upgrade, _Locks, State) ->
     {Apps, State};
-handle_profile_level([{Profile, Deps, Level} | Rest], Apps, Seen, Upgrade, Locks, State) ->
+handle_profile_level([{Profile, Deps, Level} | Rest], Apps, RootSeen, Seen, Upgrade, Locks, State) ->
+    Deps0 = [rebar_app_utils:expand_deps_sources(Dep, State)
+             || Dep <- Deps,
+                %% skip top-level apps being double-declared
+                not sets:is_element(rebar_app_info:name(Dep), RootSeen)],
     {Deps1, Apps1, State1, Seen1} =
-        update_deps(Profile, Level, Deps, Apps
+        update_deps(Profile, Level, Deps0, Apps
                    ,State, Upgrade, Seen, Locks),
     Deps2 = case Deps1 of
         [] -> Rest;
         _ -> Rest ++ [{Profile, Deps1, Level+1}]
     end,
-    handle_profile_level(Deps2, Apps1, sets:union(Seen, Seen1), Upgrade, Locks, State1).
+    handle_profile_level(Deps2, Apps1, RootSeen, sets:union(Seen, Seen1), Upgrade, Locks, State1).
 
 find_cycles(Apps) ->
     case rebar_digraph:compile_order(Apps) of

test/rebar_deps_SUITE.erl

@@ -7,7 +7,7 @@ all() -> [sub_app_deps, newly_added_dep, newly_added_after_empty_lock,
           http_proxy_settings, https_proxy_settings,
           http_os_proxy_settings, https_os_proxy_settings,
           semver_matching_lt, semver_matching_lte, semver_matching_gt,
-          valid_version, {group, git}, {group, pkg}].
+          valid_version, top_override, {group, git}, {group, pkg}].
 
 groups() ->
     [{all, [], [flat, pick_highest_left, pick_highest_right,
@@ -47,6 +47,8 @@ init_per_testcase(newly_added_dep, Config) ->
     rebar_test_utils:init_rebar_state(Config);
 init_per_testcase(sub_app_deps, Config) ->
     rebar_test_utils:init_rebar_state(Config);
+init_per_testcase(top_override, Config) ->
+    rebar_test_utils:init_rebar_state(Config);
 init_per_testcase(http_proxy_settings, Config) ->
     %% Create private rebar.config
     Priv = ?config(priv_dir, Config),
@@ -255,6 +257,32 @@ circular1(Config) -> run(Config).
 circular2(Config) -> run(Config).
 circular_skip(Config) -> run(Config).
 
+%% Test that a top-level application overtakes dependencies, and
+%% works even if said deps do not exist.
+top_override(Config) ->
+    AppDir = ?config(apps, Config),
+    ct:pal("dir: ~p", [AppDir]),
+    Name1 = rebar_test_utils:create_random_name("sub_app1_"),
+    Name2 = rebar_test_utils:create_random_name("sub_app2_"),
+    SubAppsDir1 = filename:join([AppDir, "apps", Name1]),
+    SubAppsDir2 = filename:join([AppDir, "apps", Name2]),
+    Vsn = rebar_test_utils:create_random_vsn(),
+    rebar_test_utils:create_app(SubAppsDir1, Name1, Vsn, [kernel, stdlib]),
+    rebar_test_utils:create_app(SubAppsDir2, Name2, Vsn, [kernel, stdlib]),
+    rebar_test_utils:create_config(
+      SubAppsDir1,
+      [{deps, [list_to_atom(Name2)]}]
+     ),
+    rebar_test_utils:create_config(
+      SubAppsDir2,
+      [{deps, [{list_to_atom(Name1),
+                {git, "https://example.org", {branch, "master"}}}]}]
+    ),
+    rebar_test_utils:run_and_check(
+      Config, [], ["compile"],
+      {ok, [{app, Name1}, {app,Name2}]}
+    ).
+
 %% Test that the deps of project apps that have their own rebar.config
 %% are included, but that top level rebar.config deps take precedence
 sub_app_deps(Config) ->