Merge pull request #31 from inaka/jfacorro.3.cli.tool

[#3] Implemented a command line interface for Elvis.

.gitignore

@@ -7,3 +7,6 @@ ebin
 *.plt
 erl_crash.dump
 logs
+
+# Ignore elvis escript
+elvis

Makefile

@@ -1,9 +1,10 @@
 PROJECT = elvis
 
-DEPS = lager sync
+DEPS = lager sync getopt
 
-dep_lager = https://github.com/basho/lager.git master
+dep_lager = https://github.com/basho/lager.git 2.0.3
 dep_sync = https://github.com/rustyio/sync.git master
+dep_getopt = https://github.com/jcomellas/getopt v0.8.2
 
 include erlang.mk
 
@@ -17,3 +18,8 @@ ERLC_OPTS += +warn_export_vars +warn_exported_vars +warn_missing_spec +warn_unty
 TEST_ERLC_OPTS += +'{parse_transform, lager_transform}'
 CT_SUITES = elvis
 CT_OPTS = -cover test/elvis.coverspec  -erl_args -config config/test
+
+# Builds the elvis escript.
+escript: all
+	rebar escriptize
+	./elvis help

config/elvis-test.config

@@ -0,0 +1,9 @@
+[
+ {src_dirs, ["../../src"]},
+ {rules,
+  [
+   {elvis_style, line_length, [80]},
+   {elvis_style, no_tabs, []}
+  ]
+ }
+].

config/elvis.config

@@ -0,0 +1,9 @@
+[
+ {src_dirs, ["src", "test"]},
+ {rules,
+  [
+   {elvis_style, line_length, [80]},
+   {elvis_style, no_tabs, []}
+  ]
+ }
+].

rebar.config

@@ -21,6 +21,9 @@
 {deps_dir, "deps"}.
 {deps,
  [
-  {lager, "2.*", {git, "git@github.com:basho/lager.git", "2.0.0"}}
+  {lager, "2.*", {git, "git@github.com:basho/lager.git", "2.0.0"}},
+  {getopt, "0.*", {git, "git@github.com:jcomellas/getopt.git", "v0.8.2"}}
  ]
 }.
+{escript_name, "elvis"}.
+{escript_incl_apps, [getopt]}.

src/elvis.erl

@@ -2,24 +2,43 @@
 
 %% Public API
 
+-export([
+         main/1
+        ]).
+
 -export([
          rock/0,
          rock/1
         ]).
 
+-define(APP_NAME, "elvis").
+
 -export_type([
               config/0
              ]).
 
 -type config() :: [{atom(), term()}].
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-%% Public API
+%%% Public API
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
+-spec main([string()]) -> ok.
+main(Args) ->
+    OptSpecList = option_spec_list(),
+    case getopt:parse(OptSpecList, Args) of
+        {ok, {[], []}} ->
+            help();
+        {ok, {Options, Commands}} ->
+            process_options(Options, Commands);
+        {error, {Reason, Data}} ->
+            io:format("Error: ~s ~p~n~n", [Reason, Data]),
+            help()
+    end.
+
 -spec rock() -> ok.
 rock() ->
-    Config = application:get_all_env(elvis),
+    Config = default_config(),
     rock(Config).
 
 -spec rock(config()) -> ok.
@@ -32,9 +51,11 @@ rock(Config) ->
     end.
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-%% Private
+%%% Private
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
+%%% Rocking it hard
+
 -spec run(config()) -> ok.
 run(Config) ->
     SrcDirs = elvis_utils:source_dirs(Config),
@@ -54,3 +75,90 @@ apply_rule({Module, Function, Args}, {Result, Config, FilePath}) ->
     Results = Module:Function(Config, FilePath, Args),
     RuleResult = elvis_result:new(rule, Function, Results),
     {[RuleResult | Result], Config, FilePath}.
+
+
+%%% Command Line Interface
+
+-spec option_spec_list() -> [getopt:option_spec()].
+option_spec_list() ->
+    Commands = "Provide the path to the configuration file.",
+    [
+     {help, $h, "help", undefined, "Show this help information."},
+     {config, $c, "config", string, Commands},
+     {commands, undefined, "commands", undefined, "Show available commands."}
+    ].
+
+-spec process_options([atom()], [string()]) -> ok.
+process_options(Options, Commands) ->
+    try
+        Config = default_config(),
+        process_options(Options, Commands, Config)
+    catch
+        throw:Exception ->
+            io:format("Error: ~p.~n", [Exception])
+    end.
+
+-spec process_options([atom()], [string()], config()) -> ok.
+process_options([help | Opts], Cmds, Config) ->
+    help(),
+    process_options(Opts, Cmds, Config);
+process_options([{config, Path} | Opts], Cmds, _) ->
+    Config = config(Path),
+    process_options(Opts, Cmds, Config);
+process_options([commands | Opts], Cmds, Config) ->
+    commands(),
+    process_options(Opts, Cmds, Config);
+process_options([], Cmds, Config) ->
+    process_commands(Cmds, Config).
+
+-spec process_commands([string()], config()) -> ok.
+process_commands(["rock" | Cmds], Config) ->
+    rock(Config),
+    process_commands(Cmds, Config);
+process_commands(["help" | Cmds], Config) ->
+    Config = help(Config),
+    process_commands(Cmds, Config);
+process_commands([], _Config) ->
+    ok;
+process_commands([_Cmd | _Cmds], _Config) ->
+    throw(unrecognized_or_unimplemened_command).
+
+-spec default_config() -> config().
+default_config() ->
+    case file:consult("./elvis.config") of
+        {ok, [Config]} ->
+            Config;
+        {error, enoent} ->
+            application:get_all_env(elvis);
+        {error, Reason} ->
+            throw(Reason)
+    end.
+
+%%% Options
+
+-spec help() -> ok.
+help() ->
+    OptSpecList = option_spec_list(),
+    getopt:usage(OptSpecList, ?APP_NAME, standard_io).
+
+-spec help(config()) -> config().
+help(Config) ->
+    help(),
+    Config.
+
+-spec config(string()) -> config().
+config(Path) ->
+    case file:consult(Path) of
+        {ok, [Config]} ->
+            Config;
+        {error, Reason} ->
+            throw(Reason)
+    end.
+
+-spec commands() -> ok.
+commands() ->
+    Commands = <<"Elvis will do the following things for you when asked nicely:
+
+rock             Rock your socks off by running all rules to your source files.
+">>,
+   io:put_chars(Commands).

test/elvis_SUITE.erl

@@ -13,7 +13,13 @@
          check_configuration/1,
          find_file_and_check_src/1,
          verify_line_length_rule/1,
-         verify_no_tabs_rule/1
+         verify_no_tabs_rule/1,
+         main_help/1,
+         main_commands/1,
+         main_config/1,
+         main_rock/1,
+         main_default_config/1,
+         main_unexistent/1
         ]).
 
 -define(EXCLUDED_FUNS,
@@ -34,8 +40,7 @@
 -spec all() -> [atom()].
 all() ->
     Exports = elvis_SUITE:module_info(exports),
-    [F || {F, _} <- Exports,
-          lists:all(fun(E) -> E /= F end, ?EXCLUDED_FUNS)].
+    [F || {F, _} <- Exports, not lists:member(F, ?EXCLUDED_FUNS)].
 
 -spec init_per_suite(config()) -> config().
 init_per_suite(Config) ->
@@ -51,6 +56,9 @@ end_per_suite(Config) ->
 %% Test Cases
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
+%%%%%%%%%%%%%%%
+%%% Rocking
+
 -spec rock_with_empty_config(config()) -> any().
 rock_with_empty_config(_Config) ->
     ok = try
@@ -72,7 +80,13 @@ rock_with_incomplete_config(_Config) ->
 
 -spec rock_with_file_config(config()) -> ok.
 rock_with_file_config(_Config) ->
-    ok = elvis:rock().
+    Fun = fun() -> elvis:rock() end,
+    Expected = "# ../../test/examples/fail_line_length.erl [FAIL]\n",
+    check_first_line_output(Fun, Expected),
+    ok.
+
+%%%%%%%%%%%%%%%
+%%% Utils
 
 -spec check_configuration(config()) -> any().
 check_configuration(_Config) ->
@@ -93,9 +107,8 @@ find_file_and_check_src(_Config) ->
     {ok, <<"-module(small).\n">>} = elvis_utils:src([], Path),
     {error, enoent} = elvis_utils:src([], "doesnt_exist.erl").
 
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-%% Rules
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%%%
+%%% Rules
 
 -spec verify_line_length_rule(config()) -> any().
 verify_line_length_rule(_Config) ->
@@ -124,3 +137,112 @@ verify_no_tabs_rule(_Config) ->
         2 -> ok;
         _ -> tabs_undetected
     end.
+
+%%%%%%%%%%%%%%%
+%%% CLI
+
+-spec main_help(config()) -> any().
+main_help(_Config) ->
+    Expected = "Usage: elvis",
+
+    ShortOptFun = fun() -> elvis:main("-h") end,
+    check_first_line_output(ShortOptFun, Expected, fun starts_with/2),
+
+    LongOptFun = fun() -> elvis:main("--help") end,
+    check_first_line_output(LongOptFun, Expected, fun starts_with/2),
+
+    EmptyFun = fun() -> elvis:main("") end,
+    check_first_line_output(EmptyFun, Expected, fun starts_with/2),
+
+    CmdFun = fun() -> elvis:main("help") end,
+    check_first_line_output(CmdFun, Expected, fun starts_with/2),
+
+    ok.
+
+-spec main_commands(config()) -> any().
+main_commands(_Config) ->
+    Expected = "Elvis will do the following things",
+
+    OptFun = fun() -> elvis:main("--commands") end,
+    check_first_line_output(OptFun, Expected, fun starts_with/2),
+
+    ok.
+
+-spec main_config(config()) -> any().
+main_config(_Config) ->
+    Expected = "Error: missing_option_arg config",
+
+    OptFun = fun() -> elvis:main("-c") end,
+    check_first_line_output(OptFun, Expected, fun starts_with/2),
+
+    EnoentExpected = "Error: enoent.\n",
+    OptEnoentFun = fun() -> elvis:main("-c missing") end,
+    check_first_line_output(OptEnoentFun, EnoentExpected),
+
+    ConfigFileFun = fun() -> elvis:main("-c ../../config/elvis.config") end,
+    check_first_line_output(ConfigFileFun, ""),
+
+    ok.
+
+-spec main_rock(config()) -> any().
+main_rock(_Config) ->
+    ExpectedFail = "# ../../test/examples/fail_line_length.erl [FAIL]\n",
+
+    NoConfigArgs = "rock",
+    NoConfigFun = fun() -> elvis:main(NoConfigArgs) end,
+    check_first_line_output(NoConfigFun, ExpectedFail, fun starts_with/2),
+
+    Expected = "# ../../src/elvis.erl [OK]",
+
+    ConfigArgs = "rock -c ../../config/elvis-test.config",
+    ConfigFun = fun() -> elvis:main(ConfigArgs) end,
+    check_first_line_output(ConfigFun, Expected, fun starts_with/2),
+
+    ok.
+
+-spec main_default_config(config()) -> any().
+main_default_config(_Config) ->
+    Src = "../../config/elvis-test.config",
+    Dest = "./elvis.config",
+    file:copy(Src, Dest),
+
+    Expected = "# ../../src/elvis.erl [OK]",
+    RockFun = fun() -> elvis:main("rock") end,
+    check_first_line_output(RockFun, Expected, fun starts_with/2),
+
+    file:delete(Dest),
+
+    ok.
+
+-spec main_unexistent(config()) -> any().
+main_unexistent(_Config) ->
+    Expected = "Error: unrecognized_or_unimplemened_command.\n",
+
+    UnexistentFun = fun() -> elvis:main("aaarrrghh") end,
+    check_first_line_output(UnexistentFun, Expected),
+
+    ok.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%% Private
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+check_first_line_output(Fun, Expected) ->
+    Equals = fun(Result, Exp) ->
+                 Result = Exp
+             end,
+    check_first_line_output(Fun, Expected, Equals).
+
+check_first_line_output(Fun, Expected, CheckFun) ->
+    ct:capture_start(),
+    Fun(),
+    ct:capture_stop(),
+    Result = case ct:capture_get([]) of
+                 [] -> "";
+                 [Head | _] -> Head
+             end,
+
+    CheckFun(Result, Expected).
+
+starts_with(Result, Expected) ->
+    1 = string:str(Result, Expected).