[erl-frontend] rebar3 wrapper for Erlang projects

Reviewed By: jvillard

Differential Revision: D27767581

fbshipit-source-id: 393f787f5

infer/lib/erlang/erlang.escript

@@ -0,0 +1,146 @@
+#!/usr/bin/env escript
+% Copyright (c) Facebook, Inc. and its affiliates.
+%
+% This source code is licensed under the MIT license found in the
+% LICENSE file in the root directory of this source tree.
+%
+%
+% Usage:
+%     erlang.escript [ast_out_dir] -- rebar3 [args ...]
+%     erlang.escript [ast_out_dir] -- erlc [args ...]
+%
+% This script produces a bash command that makes rebar3 or erlc
+% to execute with [args ...], and in addition to write the JSON
+% representation of the Erlang AST for each file compiled
+% in [ast_out_dir] or - if not provided - in the build
+% directory next to the corresponding compiled beam.
+
+main([]) ->
+    usage();
+main(Args) ->
+    {SArgs, Cmd} = split_args(Args),
+    OutDir =
+        case SArgs of
+            [] -> false;
+            [Dir] -> Dir;
+            _ -> usage()
+        end,
+    ScriptDir = filename:dirname(escript:script_name()),
+    ParseTransformDir = filename:join(ScriptDir, "infer_parse_transform"),
+    case run("rebar3 compile", ParseTransformDir) of
+        0 ->
+            ok;
+        ExitStatus ->
+            io:format("error: `rebar3 compile` in `~s` returned exit code ~p~n", [
+                ParseTransformDir,
+                ExitStatus
+            ]),
+            halt(1)
+    end,
+    LibPath = filename:join(ParseTransformDir, "_build/default/lib"),
+    case Cmd of
+        ["rebar3" | _] ->
+            rebar3(LibPath, OutDir, Cmd);
+        ["erlc" | _] ->
+            erlc(LibPath, OutDir, Cmd);
+        _ ->
+            io:format("error: unrecognized command ~s~n", [string:join(Cmd, " ")]),
+            halt(1)
+    end.
+
+usage() ->
+    io:format("valid arguments:~n"),
+    io:format("  [ast_out_dir] -- rebar3 [args] ...~n"),
+    io:format("  [ast_out_dir] -- erlc [args] ...~n"),
+    halt(1).
+
+load_config_from_list([]) ->
+    false;
+load_config_from_list([H | T]) ->
+    case load_config(H) of
+        {ok, Config} -> Config;
+        _ -> load_config_from_list(T)
+    end.
+
+load_config(ConfigPath) when is_list(ConfigPath) ->
+    case lists:suffix(".script", ConfigPath) of
+        true ->
+            BaseConfigPath = filename:rootname(ConfigPath, ".script"),
+            BaseConfig =
+                case load_config(BaseConfigPath) of
+                    {ok, Config} -> Config;
+                    _ -> []
+                end,
+            file:script(ConfigPath, [{'CONFIG', BaseConfig}, {'SCRIPT', ConfigPath}]);
+        false ->
+            file:consult(ConfigPath)
+    end;
+load_config(_) ->
+    false.
+
+split_args(Args) ->
+    try
+        split_args_rec(Args, [])
+    catch
+        _:_ -> usage()
+    end.
+
+split_args_rec(["--" | RebarCmd], Args) -> {Args, RebarCmd};
+split_args_rec([H | T], Args) -> split_args_rec(T, Args ++ [H]).
+
+run(Command, Dir) ->
+    Port = erlang:open_port(
+        {spawn, Command},
+        [exit_status, {cd, Dir}]
+    ),
+    receive
+        {Port, {exit_status, Status}} -> Status
+    end.
+
+rebar3(LibPath, OutDir, Cmd) ->
+    ConfigPaths = [os:getenv("REBAR_CONFIG"), "rebar.config.script", "rebar.config"],
+    Original =
+        case load_config_from_list(ConfigPaths) of
+            false ->
+                io:format("error: no rebar3 config found~n"),
+                halt(1);
+            Config ->
+                Config
+        end,
+    Altered = inject_parse_transform(Original, OutDir),
+    AltConfigPath = string:trim(os:cmd("mktemp --suffix .script")),
+    file:write_file(AltConfigPath, io_lib:fwrite("~p.~n", [Altered])),
+
+    io:format("ERL_LIBS=\"~s:$ERL_LIBS\" REBAR_CONFIG=\"~s\" ~s~n", [
+        LibPath,
+        AltConfigPath,
+        string:join(Cmd, " ")
+    ]).
+
+erlc(LibPath, OutDir, Cmd) ->
+    [{erl_opts, Options}] = inject_parse_transform([], OutDir),
+    OptionList = ["+'" ++ io_lib:format("~p", [Item]) ++ "'" || Item <- Options],
+    [ErlC | Args] = Cmd,
+    io:format("ERL_LIBS=\"~s:$ERL_LIBS\" ~s ~s ~s~n", [
+        LibPath,
+        ErlC,
+        string:join(OptionList, " "),
+        string:join(Args, " ")
+    ]).
+
+inject_parse_transform(Original, OutDir) ->
+    ErlOpts =
+        case lists:keyfind(erl_opts, 1, Original) of
+            {erl_opts, Opts} -> Opts;
+            false -> []
+        end,
+    ErlOpts1 =
+        ErlOpts ++
+            [{parse_transform, infer_parse_transform}] ++
+            if
+                OutDir =/= false ->
+                    [{ast_outdir, OutDir}];
+                true ->
+                    []
+            end,
+    lists:keystore(erl_opts, 1, Original, {erl_opts, ErlOpts1}).

infer/lib/erlang/erlang.sh

@@ -0,0 +1,18 @@
+#!/bin/bash
+# Copyright (c) Facebook, Inc. and its affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+set -o pipefail
+set -u
+
+basedir=$(dirname "${BASH_SOURCE[0]}")
+out=$("${basedir}"/erlang.escript "$@")
+exit_code=$?
+echo "$out"
+if [ $exit_code = 0 ]; then
+    sh -c "$out"
+    exit $?
+fi
+exit $exit_code

infer/lib/erlang/infer_parse_transform/rebar.config

@@ -0,0 +1,9 @@
+% Copyright (c) Facebook, Inc. and its affiliates.
+%
+% This source code is licensed under the MIT license found in the
+% LICENSE file in the root directory of this source tree.
+
+{erl_opts, []}.
+{deps, [
+    {jsone, {git, "https://github.com/sile/jsone.git", {tag, "1.5.6"}}}
+]}.

infer/lib/erlang/infer_parse_transform/src/infer_parse_transform.app.src

@@ -0,0 +1,16 @@
+% Copyright (c) Facebook, Inc. and its affiliates.
+%
+% This source code is licensed under the MIT license found in the
+% LICENSE file in the root directory of this source tree.
+
+{application, infer_parse_transform,
+ [{description, "parse_transform to dump the Erlang AST as a JSON structure"},
+  {vsn, "0.1.0"},
+  {registered, []},
+  {applications,
+   [kernel,
+    stdlib,
+    jsone
+   ]},
+  {env,[]}
+ ]}.

infer/lib/erlang/infer_parse_transform/src/infer_parse_transform.erl

@@ -0,0 +1,50 @@
+% Copyright (c) Facebook, Inc. and its affiliates.
+%
+% This source code is licensed under the MIT license found in the
+% LICENSE file in the root directory of this source tree.
+
+-module(infer_parse_transform).
+
+-export([parse_transform/2]).
+
+-type forms() :: erl_parse:abstract_form() | erl_parse:form_info().
+
+-spec parse_transform([forms()], [compile:option()]) -> [forms()].
+parse_transform(Forms, Options) ->
+    OutDir =
+        case lists:keyfind(ast_outdir, 1, Options) of
+            {ast_outdir, Dir} ->
+                Dir;
+            _ ->
+                case lists:keyfind(outdir, 1, Options) of
+                    {outdir, Dir} -> Dir;
+                    _ -> error(abort)
+                end
+        end,
+    FileName =
+        case lists:keyfind(file, 3, Forms) of
+            {attribute, _, file, {FilePath, _}} -> filename:basename(FilePath);
+            _ -> error(abort)
+        end,
+    dump_ast_as_json(OutDir, FileName, Forms),
+    Forms.
+
+dump_ast_as_json(Dir, SourceFileName, Forms) ->
+    FileName = filename:rootname(SourceFileName) ++ ".json",
+    FilePath = filename:join(Dir, FileName),
+    Object = ast_to_json(Forms),
+    Contents = jsone:encode(Object),
+    file:write_file(FilePath, Contents).
+
+ast_to_json([]) ->
+    [];
+ast_to_json(Node) when is_list(Node) ->
+    case lists:all(fun(Item) -> is_integer(Item) end, Node) of
+        true -> unicode:characters_to_binary(Node);
+        false -> [ast_to_json(Child) || Child <- Node]
+    end;
+ast_to_json(Node) when is_tuple(Node) ->
+    L = tuple_to_list(Node),
+    ast_to_json(L);
+ast_to_json(Node) ->
+    Node.