Initial tests for dependency resolving

- Reworked the helpers for existing suites and expanded them
- Created a mock git resource module to test for its dependency fetching
- Added a test suite for dependency resolving with first checks for
  common cases (https://gist.github.com/ferd/197cc5c0b85aae370436)

Left to do would include:

- Verify warnings
- Verify failures
- Verify dependency updates resolving

rebar.config

@@ -30,7 +30,8 @@
        {relx, "",
         {git, "https://github.com/tsloughter/relx.git",
          {branch, "format_error1"}}},
-       {getopt, "", {git, "https://github.com/jcomellas/getopt.git", {branch, "master"}}}]}.
+       {getopt, "", {git, "https://github.com/jcomellas/getopt.git", {branch, "master"}}},
+       {meck, "", {git, "https://github.com/eproxus/meck.git", {tag, "0.8.2"}}}]}.
 
 {erlydtl_opts, [{doc_root, "priv/templates"},
                 {compiler_options, [report, return, debug_info]}]}.

test/mock_git_resource.erl

@@ -0,0 +1,129 @@
+%%% Mock a git resource and create an app magically for each URL submitted.
+-module(mock_git_resource).
+-export([mock/0, mock/1, unmock/0]).
+-define(MOD, rebar_git_resource).
+
+%%%%%%%%%%%%%%%%%
+%%% Interface %%%
+%%%%%%%%%%%%%%%%%
+
+%% @doc same as `mock([])'.
+mock() -> mock([]).
+
+%% @doc Mocks a fake version of the git resource fetcher that creates
+%% empty applications magically, rather than trying to download them.
+%% Specific config options are explained in each of the private functions.
+-spec mock(Opts) -> ok when
+    Opts :: [Option],
+    Option :: {update, [App]}
+            | {default_vsn, Vsn}
+            | {override_vsn, [{App, Vsn}]}
+            | {deps, [{App, [Dep]}]},
+    App :: string(),
+    Dep :: {App, string(), {git, string()} | {git, string(), term()}},
+    Vsn :: string().
+mock(Opts) ->
+    meck:new(?MOD, [no_link]),
+    mock_lock(Opts),
+    mock_update(Opts),
+    mock_vsn(Opts),
+    mock_download(Opts),
+    ok.
+
+unmock() ->
+    meck:unload(?MOD).
+
+%%%%%%%%%%%%%%%
+%%% Private %%%
+%%%%%%%%%%%%%%%
+
+%% @doc creates values for a lock file. The refs are fake, but
+%% tags and existing refs declared for a dependency are preserved.
+mock_lock(_) ->
+    meck:expect(
+        ?MOD, lock,
+        fun(_AppDir, Git) ->
+            case Git of
+                {git, Url, {tag, Ref}} -> {git, Url, {ref, Ref}};
+                {git, Url, {ref, Ref}} -> {git, Url, {ref, Ref}};
+                {git, Url} -> {git, Url, {ref, "fake-ref"}};
+                {git, Url, _} -> {git, Url, {ref, "fake-ref"}}
+            end
+        end).
+
+%% @doc The config passed to the `mock/2' function can specify which apps
+%% should be updated on a per-name basis: `{update, ["App1", "App3"]}'.
+mock_update(Opts) ->
+    ToUpdate = proplists:get_value(update, Opts, []),
+    meck:expect(
+        ?MOD, needs_update,
+        fun(_Dir, {git, Url, _Ref}) ->
+            App = app(Url),
+            lists:member(App, ToUpdate)
+        end).
+
+%% @doc Tries to fetch a version from the `*.app.src' file or otherwise
+%% just returns random stuff, avoiding to check for the presence of git.
+%% This probably breaks the assumption that stable references are returned.
+%%
+%% This function can't respect the `override_vsn' option because if the
+%% .app.src file isn't there, we can't find the app name either.
+mock_vsn(Opts) ->
+    Default = proplists:get_value(default_vsn, Opts, "0.0.0"),
+    meck:expect(
+        ?MOD, make_vsn,
+        fun(Dir) ->
+            case filelib:wildcard("*.app.src", filename:join([Dir,"src"])) of
+                [AppSrc] ->
+                    {ok, App} = file:consult(AppSrc),
+                    Vsn = proplists:get_value(vsn, App),
+                    {plain, Vsn};
+                _ ->
+                    {plain, Default}
+            end
+        end).
+
+%% @doc For each app to download, create a dummy app on disk instead.
+%% The configuration for this one (passed in from `mock/1') includes:
+%%
+%% - Specify a version, branch, ref, or tag via the `{git, URL, {_, Vsn}'
+%%   format to specify a path.
+%% - If there is no version submitted (`{git, URL}'), the function instead
+%%   reads from the `override_vsn' proplist (`{override_vsn, {"App1","1.2.3"}'),
+%%   and otherwise uses the value associated with `default_vsn'.
+%% - Dependencies for each application must be passed of the form:
+%%   `{deps, [{"app1", [{app2, ".*", {git, ...}}]}]}' -- basically
+%%   the `deps' option takes a key/value list of terms to output directly
+%%   into a `rebar.config' file to describe dependencies.
+mock_download(Opts) ->
+    Deps = proplists:get_value(deps, Opts, []),
+    Default = proplists:get_value(default_vsn, Opts, "0.0.0"),
+    Overrides = proplists:get_value(override_vsn, Opts, []),
+    meck:expect(
+        ?MOD, download,
+        fun (Dir, Git) ->
+            {git, Url, {_, Vsn}} = normalize_git(Git, Overrides, Default),
+            filelib:ensure_dir(Dir),
+            App = app(Url),
+            AppDeps = proplists:get_value(App, Deps, []),
+            rebar_test_utils:create_app(
+                Dir, App, Vsn,
+                [element(1,D) || D  <- AppDeps]
+            ),
+            rebar_test_utils:create_config(Dir, [{deps, AppDeps}]),
+            {ok, 'WHATEVER'}
+        end).
+
+%%%%%%%%%%%%%%%
+%%% Helpers %%%
+%%%%%%%%%%%%%%%
+app(Path) ->
+    filename:basename(Path, ".git").
+
+normalize_git({git, Url}, Overrides, Default) ->
+    Vsn = proplists:get_value(app(Url), Overrides, Default),
+    {git, Url, {tag, Vsn}};
+normalize_git({git, Url, Branch}, _, _) when is_list(Branch) ->
+    {git, Url, {branch, Branch}};
+normalize_git(Git, _, _) ->
+    Git.

test/rebar_compile_SUITE.erl

@@ -10,7 +10,6 @@
 -include_lib("common_test/include/ct.hrl").
 -include_lib("eunit/include/eunit.hrl").
 -include_lib("kernel/include/file.hrl").
--include_lib("kernel/include/file.hrl").
 
 suite() ->
     [].
@@ -22,95 +21,17 @@ end_per_suite(_Config) ->
     ok.
 
 init_per_testcase(_, Config) ->
-    DataDir = proplists:get_value(data_dir, Config),
-    AppsDir = filename:join([DataDir, create_random_name("apps_dir1_")]),
-    ok = ec_file:mkdir_p(AppsDir),
-    Verbosity = rebar3:log_level(),
-    rebar_log:init(command_line, Verbosity),
-    State = rebar_state:new(),
-    [{apps, AppsDir}, {state, State} | Config].
+    rebar_test_utils:init_rebar_state(Config).
 
 all() ->
     [build_basic_app].
 
 build_basic_app(Config) ->
-    AppDir = proplists:get_value(apps, Config),
-
-    Name = create_random_name("app1_"),
-    Vsn = create_random_vsn(),
-    create_app(AppDir, Name, Vsn, [kernel, stdlib]),
-
-    run_and_check(Config, [], "compile", [{app, Name}]).
-
-%%%===================================================================
-%%% Helper Functions
-%%%===================================================================
-
-run_and_check(Config, RebarConfig, Command, Expect) ->
-    AppDir = proplists:get_value(apps, Config),
-    State = proplists:get_value(state, Config),
-
-    rebar3:run(rebar_state:new(State, RebarConfig, AppDir), Command),
-
-    lists:foreach(fun({app, Name}) ->
-                          [App] = rebar_app_discover:find_apps([AppDir]),
-                          ?assertEqual(Name, ec_cnv:to_list(rebar_app_info:name(App)))
-                  end, Expect).
-
-create_app(AppDir, Name, Vsn, Deps) ->
-    write_src_file(AppDir, Name),
-    write_app_src_file(AppDir, Name, Vsn, Deps),
-    rebar_app_info:new(Name, Vsn, AppDir, Deps).
-
-create_empty_app(AppDir, Name, Vsn, Deps) ->
-    write_app_file(AppDir, Name, Vsn, Deps),
-    rebar_app_info:new(Name, Vsn, AppDir, Deps).
-
-write_beam_file(Dir, Name) ->
-    Beam = filename:join([Dir, "ebin", "not_a_real_beam" ++ Name ++ ".beam"]),
-    ok = filelib:ensure_dir(Beam),
-    ok = ec_file:write_term(Beam, testing_purposes_only).
-
-write_src_file(Dir, Name) ->
-    Erl = filename:join([Dir, "src", "not_a_real_src" ++ Name ++ ".erl"]),
-    ok = filelib:ensure_dir(Erl),
-    ok = ec_file:write(Erl, erl_src_file("not_a_real_src" ++ Name ++ ".erl")).
-
-write_app_file(Dir, Name, Version, Deps) ->
-    Filename = filename:join([Dir, "ebin", Name ++ ".app"]),
-    ok = filelib:ensure_dir(Filename),
-    ok = ec_file:write_term(Filename, get_app_metadata(ec_cnv:to_list(Name), Version, Deps)).
-
-write_app_src_file(Dir, Name, Version, Deps) ->
-    Filename = filename:join([Dir, "src", Name ++ ".app.src"]),
-    ok = filelib:ensure_dir(Filename),
-    ok = ec_file:write_term(Filename, get_app_metadata(ec_cnv:to_list(Name), Version, Deps)).
-
-get_app_metadata(Name, Vsn, Deps) ->
-    {application, erlang:list_to_atom(Name),
-     [{description, ""},
-      {vsn, Vsn},
-      {modules, []},
-      {included_applications, []},
-      {registered, []},
-      {applications, Deps}]}.
-
-create_random_name(Name) ->
-    random:seed(erlang:now()),
-    Name ++ erlang:integer_to_list(random:uniform(1000000)).
+    AppDir = ?config(apps, Config),
 
-create_random_vsn() ->
-    random:seed(erlang:now()),
-    lists:flatten([erlang:integer_to_list(random:uniform(100)),
-                   ".", erlang:integer_to_list(random:uniform(100)),
-                   ".", erlang:integer_to_list(random:uniform(100))]).
+    Name = rebar_test_utils:create_random_name("app1_"),
+    Vsn = rebar_test_utils:create_random_vsn(),
+    rebar_test_utils:create_app(AppDir, Name, Vsn, [kernel, stdlib]),
 
-write_config(Filename, Values) ->
-    ok = filelib:ensure_dir(Filename),
-    ok = ec_file:write(Filename,
-                       [io_lib:format("~p.\n", [Val]) || Val <- Values]).
+    rebar_test_utils:run_and_check(Config, [], "compile", [{app, Name}]).
 
-erl_src_file(Name) ->
-    io_lib:format("-module(~s).\n"
-                 "-export([main/0]).\n"
-                 "main() -> ok.\n", [filename:basename(Name, ".erl")]).

test/rebar_deps_SUITE.erl

@@ -0,0 +1,85 @@
+%%% TODO: check that warnings are appearing
+-module(rebar_deps_SUITE).
+-compile(export_all).
+-include_lib("common_test/include/ct.hrl").
+-include_lib("eunit/include/eunit.hrl").
+
+all() -> [flat, pick_highest_left, pick_highest_right, pick_earliest].
+
+init_per_suite(Config) ->
+    application:start(meck),
+    Config.
+
+end_per_suite(_Config) ->
+    application:stop(meck).
+
+init_per_testcase(Case, Config) ->
+    {Deps, Expect} = deps(Case),
+    [{expect,
+      [case Dep of
+        {N,V} -> {dep, N, V};
+        N -> {dep, N}
+       end || Dep <- Expect]}
+     | setup_project(Case, Config, expand_deps(Deps))].
+
+deps(flat) ->
+    {[{"B", []},
+      {"C", []}],
+     ["B", "C"]};
+deps(pick_highest_left) ->
+    {[{"B", [{"C", "2", []}]},
+      {"C", "1", []}],
+     ["B", {"C", "1"}]}; % Warn C2
+deps(pick_highest_right) ->
+    {[{"B", "1", []},
+      {"C", [{"B", "2", []}]}],
+     [{"B","1"}, "C"]}; % Warn B2
+deps(pick_earliest) ->
+    {[{"B", [{"D", "1", []}]},
+      {"C", [{"D", "2", []}]}],
+     ["B","C",{"D","1"}]}. % Warn D2
+
+end_per_testcase(_, Config) ->
+    mock_git_resource:unmock(),
+    meck:unload(),
+    Config.
+
+expand_deps([]) -> [];
+expand_deps([{Name, Deps} | Rest]) ->
+    Dep = {Name, ".*", {git, "https://example.org/user/"++Name++".git", "master"}},
+    [{Dep, expand_deps(Deps)} | expand_deps(Rest)];
+expand_deps([{Name, Vsn, Deps} | Rest]) ->
+    Dep = {Name, Vsn, {git, "https://example.org/user/"++Name++".git", {tag, Vsn}}},
+    [{Dep, expand_deps(Deps)} | expand_deps(Rest)].
+
+setup_project(Case, Config0, Deps) ->
+    Config = rebar_test_utils:init_rebar_state(Config0, atom_to_list(Case)),
+    AppDir = ?config(apps, Config),
+    TopDeps = top_level_deps(Deps),
+    RebarConf = rebar_test_utils:create_config(AppDir, [{deps, TopDeps}]),
+    mock_git_resource:mock([{deps, flat_deps(Deps)}]),
+    [{rebarconfig, RebarConf} | Config].
+
+
+flat_deps([]) -> [];
+flat_deps([{{Name,_Vsn,_Ref}, Deps} | Rest]) ->
+    [{Name, top_level_deps(Deps)}]
+    ++
+    flat_deps(Deps)
+    ++
+    flat_deps(Rest).
+
+top_level_deps(Deps) -> [{list_to_atom(Name),Vsn,Ref} || {{Name,Vsn,Ref},_} <- Deps].
+
+%%% TESTS %%%
+flat(Config) -> run(Config).
+pick_highest_left(Config) -> run(Config).
+pick_highest_right(Config) -> run(Config).
+pick_earliest(Config) -> run(Config).
+
+run(Config) ->
+    {ok, RebarConfig} = file:consult(?config(rebarconfig, Config)),
+    rebar_test_utils:run_and_check(
+        Config, RebarConfig, "install_deps", ?config(expect, Config)
+    ).
+

test/rebar_test_utils.erl

@@ -0,0 +1,138 @@
+-module(rebar_test_utils).
+-include_lib("common_test/include/ct.hrl").
+-include_lib("eunit/include/eunit.hrl").
+-export([init_rebar_state/1, init_rebar_state/2, run_and_check/4]).
+-export([create_app/4, create_empty_app/4, create_config/2]).
+-export([create_random_name/1, create_random_vsn/0]).
+
+%%%%%%%%%%%%%%
+%%% Public %%%
+%%%%%%%%%%%%%%
+
+%% @doc {@see init_rebar_state/2}
+init_rebar_state(Config) -> init_rebar_state(Config, "apps_dir1_").
+
+%% @doc Takes a common test config and a name (string) and sets up
+%% a basic OTP app directory with a pre-configured rebar state to
+%% run tests with.
+init_rebar_state(Config, Name) ->
+    application:load(rebar),
+    DataDir = ?config(priv_dir, Config),
+    AppsDir = filename:join([DataDir, create_random_name(Name)]),
+    ok = ec_file:mkdir_p(AppsDir),
+    Verbosity = rebar3:log_level(),
+    rebar_log:init(command_line, Verbosity),
+    State = rebar_state:new([{base_dir, filename:join([AppsDir, "_build"])}]),
+    [{apps, AppsDir}, {state, State} | Config].
+
+%% @doc Takes common test config, a rebar config ([] if empty), a command to
+%% run ("install_deps", "compile", etc.), and a list of expected applications
+%% and/or dependencies to be present, and verifies whether they are all in
+%% place.
+%%
+%% The expectation list takes elements of the form:
+%% - `{app, Name :: string()}': checks that the app is properly built.
+%% - `{dep, Name :: string()}': checks that the dependency has been fetched.
+%%   Ignores the build status of the dependency.
+%% - `{dep, Name :: string(), Vsn :: string()}': checks that the dependency
+%%   has been fetched, and that a given version has been chosen. Useful to
+%%   test for conflict resolution. Also ignores the build status of the
+%%   dependency.
+%%
+%% This function assumes `init_rebar_state/1-2' has run before, in order to
+%% fetch the `apps' and `state' values from the CT config.
+run_and_check(Config, RebarConfig, Command, Expect) ->
+    %% Assumes init_rebar_state has run first
+    AppDir = ?config(apps, Config),
+    State = ?config(state, Config),
+    {ok,_} = rebar3:run(rebar_state:new(State, RebarConfig, AppDir), Command),
+    BuildDir = filename:join([AppDir, "_build", "default", "lib"]),
+    Deps = rebar_app_discover:find_apps([BuildDir], all),
+    DepsNames = [{ec_cnv:to_list(rebar_app_info:name(App)), App} || App <- Deps],
+    lists:foreach(
+        fun({app, Name}) ->
+                [App] = rebar_app_discover:find_apps([AppDir]),
+                ct:pal("Name: ~p", [Name]),
+                ?assertEqual(Name, ec_cnv:to_list(rebar_app_info:name(App)))
+        ;  ({dep, Name}) ->
+                ct:pal("Name: ~p", [Name]),
+                ?assertNotEqual(false, lists:keyfind(Name, 1, DepsNames))
+        ;  ({dep, Name, Vsn}) ->
+                ct:pal("Name: ~p, Vsn: ~p", [Name, Vsn]),
+                case lists:keyfind(Name, 1, DepsNames) of
+                    false ->
+                        error({app_not_found, Name});
+                    {Name, App} ->
+                        ?assertEqual(Vsn, rebar_app_info:original_vsn(App))
+                end
+        end, Expect).
+
+%% @doc Creates a dummy application including:
+%% - src/<file>.erl
+%% - src/<file>.app.src
+%% And returns a `rebar_app_info' object.
+create_app(AppDir, Name, Vsn, Deps) ->
+    write_src_file(AppDir, Name),
+    write_app_src_file(AppDir, Name, Vsn, Deps),
+    rebar_app_info:new(Name, Vsn, AppDir, Deps).
+
+%% @doc Creates a dummy application including:
+%% - ebin/<file>.app
+%% And returns a `rebar_app_info' object.
+create_empty_app(AppDir, Name, Vsn, Deps) ->
+    write_app_file(AppDir, Name, Vsn, Deps),
+    rebar_app_info:new(Name, Vsn, AppDir, Deps).
+
+%% @doc Creates a rebar.config file. The function accepts a list of terms,
+%% each of which will be dumped as a consult file. For example, the list
+%% `[a, b, c]' will return the consult file `a. b. c.'.
+create_config(AppDir, Contents) ->
+    Conf = filename:join([AppDir, "rebar.config"]),
+    ok = filelib:ensure_dir(Conf),
+    Config = lists:flatten([io_lib:fwrite("~p.~n", [Term]) || Term <- Contents]),
+    ok = ec_file:write(Conf, Config),
+    Conf.
+
+%% @doc Util to create a random variation of a given name.
+create_random_name(Name) ->
+    random:seed(erlang:now()),
+    Name ++ erlang:integer_to_list(random:uniform(1000000)).
+
+%% @doc Util to create a random variation of a given version.
+create_random_vsn() ->
+    random:seed(erlang:now()),
+    lists:flatten([erlang:integer_to_list(random:uniform(100)),
+                   ".", erlang:integer_to_list(random:uniform(100)),
+                   ".", erlang:integer_to_list(random:uniform(100))]).
+
+%%%%%%%%%%%%%%%
+%%% Helpers %%%
+%%%%%%%%%%%%%%%
+write_src_file(Dir, Name) ->
+    Erl = filename:join([Dir, "src", "not_a_real_src" ++ Name ++ ".erl"]),
+    ok = filelib:ensure_dir(Erl),
+    ok = ec_file:write(Erl, erl_src_file("not_a_real_src" ++ Name ++ ".erl")).
+
+write_app_file(Dir, Name, Version, Deps) ->
+    Filename = filename:join([Dir, "ebin", Name ++ ".app"]),
+    ok = filelib:ensure_dir(Filename),
+    ok = ec_file:write_term(Filename, get_app_metadata(ec_cnv:to_list(Name), Version, Deps)).
+
+write_app_src_file(Dir, Name, Version, Deps) ->
+    Filename = filename:join([Dir, "src", Name ++ ".app.src"]),
+    ok = filelib:ensure_dir(Filename),
+    ok = ec_file:write_term(Filename, get_app_metadata(ec_cnv:to_list(Name), Version, Deps)).
+
+erl_src_file(Name) ->
+    io_lib:format("-module(~s).\n"
+                 "-export([main/0]).\n"
+                 "main() -> ok.\n", [filename:basename(Name, ".erl")]).
+
+get_app_metadata(Name, Vsn, Deps) ->
+    {application, erlang:list_to_atom(Name),
+     [{description, ""},
+      {vsn, Vsn},
+      {modules, []},
+      {included_applications, []},
+      {registered, []},
+      {applications, Deps}]}.