Handle force flags in leading position

The checking of flags and the parsing of arguments is separated up.

src/rebar_prv_new.erl

@@ -32,7 +32,7 @@ init(State) ->
 
 -spec do(rebar_state:t()) -> {ok, rebar_state:t()} | {error, string()}.
 do(State) ->
-    case rebar_state:command_args(State) of
+    case strip_flags(rebar_state:command_args(State)) of
         ["help"] ->
             ?CONSOLE("Call `rebar3 new help <template>` for a detailed description~n", []),
             show_short_templates(rebar_templater:list_templates(State)),
@@ -72,6 +72,10 @@ info() ->
       "Valid command line options:~n"
       "  <template> [var=foo,...]~n", []).
 
+strip_flags([]) -> [];
+strip_flags(["-"++_|Opts]) -> strip_flags(Opts);
+strip_flags([Opt | Opts]) -> [Opt | strip_flags(Opts)].
+
 is_forced(State) ->
     {Args, _} = rebar_state:command_parsed_args(State),
     case proplists:get_value(force, Args) of

test/rebar_new_SUITE.erl

@@ -6,7 +6,8 @@
 -include_lib("common_test/include/ct.hrl").
 -include_lib("eunit/include/eunit.hrl").
 
-all() -> [app_git_user, app_hg_user, app_with_fallbacks].
+all() -> [app_git_user, app_hg_user, app_with_fallbacks,
+          app_with_flags1, app_with_flags2].
 
 
 init_per_testcase(Case, Config0) ->
@@ -95,6 +96,42 @@ app_hg_user(Config) ->
        {filename:join(["src", Name++"_app.erl"]), [Name]}
       ]).
 
+app_with_flags1(Config) ->
+    Name = ?config(name, Config),
+    rebar_test_utils:run_and_check(
+      Config, [],
+      ["new", "test_app", "-f", Name],
+      {ok, []}
+     ),
+    validate_files(
+      Config, Name,
+      [{"LICENSE", []},
+       {"README.md", []},
+       {".gitignore", []},
+       {"rebar.config", []},
+       {filename:join(["src", Name++".app.src"]), [Name]},
+       {filename:join(["src", Name++"_sup.erl"]), [Name]},
+       {filename:join(["src", Name++"_app.erl"]), [Name]}
+      ]).
+
+app_with_flags2(Config) ->
+    Name = ?config(name, Config),
+    rebar_test_utils:run_and_check(
+      Config, [],
+      ["new", "-f", "test_app", Name],
+      {ok, []}
+     ),
+    validate_files(
+      Config, Name,
+      [{"LICENSE", []},
+       {"README.md", []},
+       {".gitignore", []},
+       {"rebar.config", []},
+       {filename:join(["src", Name++".app.src"]), [Name]},
+       {filename:join(["src", Name++"_sup.erl"]), [Name]},
+       {filename:join(["src", Name++"_app.erl"]), [Name]}
+      ]).
+
 validate_files(_Config, Name, Checks) ->
     [begin
         Path = filename:join([Name, File]),