%% =====================================================================
%% Licensed under the Apache License, Version 2.0 (the "License"); you may
%% not use this file except in compliance with the License. You may obtain
%% a copy of the License at <http://www.apache.org/licenses/LICENSE-2.0>
%%
%% Unless required by applicable law or agreed to in writing, software
%% distributed under the License is distributed on an "AS IS" BASIS,
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%% See the License for the specific language governing permissions and
%% limitations under the License.
%%
%% Alternatively, you may use this file under the terms of the GNU Lesser
%% General Public License (the "LGPL") as published by the Free Software
%% Foundation; either version 2.1, or (at your option) any later version.
%% If you wish to allow use of your version of this file only under the
%% terms of the LGPL, you should delete the provisions above and replace
%% them with the notice and other provisions required by the LGPL; see
%% <http://www.gnu.org/licenses/>. If you do not delete the provisions
%% above, a recipient may use your version of this file under the terms of
%% either the Apache License or the LGPL.
%%
%% @copyright 1999-2014 Richard Carlsson
%% @author Richard Carlsson <[email protected]>
%% @end
%% =====================================================================
%% @doc Tidies and pretty-prints Erlang source code, removing unused
%% functions, updating obsolete constructs and function calls, etc.
%%
%% Caveats: It is possible that in some intricate uses of macros,
%% the automatic addition or removal of parentheses around uses or
%% arguments could cause the resulting program to be rejected by the
%% compiler; however, we have found no such case in existing
%% code. Programs defining strange macros can usually not be read by
%% this program, and in those cases, no changes will be made.
%%
%% If you really, really want to, you may call it "Inga".
%%
%% Disclaimer: The author accepts no responsibility for errors
%% introduced in code that has been processed by the program. It has
%% been reasonably well tested, but the possibility of errors remains.
%% Keep backups of your original code safely stored, until you feel
%% confident that the new, modified code can be trusted.
%%
%% @type syntaxTree() = erl_syntax:syntaxTree(). An abstract syntax
%% tree. See the {@link erl_syntax} module for details.
%%
%% @type filename() = file:filename().
-module(erl_tidy).
-export([dir/0, dir/1, dir/2, file/1, file/2, module/1, module/2]).
-include_lib("kernel/include/file.hrl").
-define(DEFAULT_BACKUP_SUFFIX, ".bak").
-define(DEFAULT_DIR, "").
-define(DEFAULT_REGEXP, ".*\\.erl$").
%% =====================================================================
-type options() :: [atom() | {atom(), any()}].
%% =====================================================================
dir__defaults() ->
[{follow_links, false},
recursive,
{regexp, ?DEFAULT_REGEXP},
verbose].
%% =====================================================================
%% @spec dir() -> ok
%% @equiv dir("")
-spec dir() -> 'ok'.
dir() ->
dir("").
%% =====================================================================
%% @spec dir(Dir) -> ok
%% @equiv dir(Dir, [])
-spec dir(file:filename()) -> 'ok'.
dir(Dir) ->
dir(Dir, []).
%% =====================================================================
%% @spec dir(Directory::filename(), Options::[term()]) -> ok
%%
%% @doc Tidies Erlang source files in a directory and its
%% subdirectories.
%%
%% Available options:
%% <dl>
%% <dt>{follow_links, boolean()}</dt>
%%
%% <dd>If the value is `true', symbolic directory
%% links will be followed. The default value is
%% `false'.</dd>
%%
%% <dt>{recursive, boolean()}</dt>
%%
%% <dd>If the value is `true', subdirectories will be
%% visited recursively. The default value is
%% `true'.</dd>
%%
%% <dt>{regexp, string()}</dt>
%%
%% <dd>The value denotes a regular expression (see module
%% `re'). Tidying will only be applied to those
%% regular files whose names match this pattern. The default
%% value is `".*\\.erl$"', which matches normal
%% Erlang source file names.</dd>
%%
%% <dt>{test, boolean()}</dt>
%%
%% <dd>If the value is `true', no files will be
%% modified. The default value is `false'.</dd>
%%
%% <dt>{verbose, boolean()}</dt>
%%
%% <dd>If the value is `true', progress messages will
%% be output while the program is running, unless the
%% `quiet' option is `true'. The default
%% value when calling {@link dir/2} is `true'.</dd>
%%
%% </dl>
%%
%% See the function {@link file/2} for further options.
%%
%% @see //stdlib/re
%% @see file/2
-record(dir, {follow_links = false :: boolean(),
recursive = true :: boolean(),
options :: options()}).
-spec dir(file:filename(), options()) -> 'ok'.
dir(Dir, Opts) ->
Opts1 = Opts ++ dir__defaults(),
Env = #dir{follow_links = proplists:get_bool(follow_links, Opts1),
recursive = proplists:get_bool(recursive, Opts1),
options = Opts1},
Regexp = proplists:get_value(regexp, Opts1),
case filename(Dir) of
"" ->
Dir1 = ".";
Dir1 ->
ok
end,
dir_1(Dir1, Regexp, Env).
dir_1(Dir, Regexp, Env) ->
case file:list_dir(Dir) of
{ok, Files} ->
lists:foreach(fun (X) -> dir_2(X, Regexp, Dir, Env) end,
Files);
{error, _} ->
report_error("error reading directory `~ts'",
[filename(Dir)]),
exit(error)
end.
dir_2(Name, Regexp, Dir, Env) ->
File = if Dir =:= "" ->
Name;
true ->
filename:join(Dir, Name)
end,
case file_type(File) of
{value, regular} ->
dir_4(File, Regexp, Env);
{value, directory} when Env#dir.recursive =:= true ->
case is_symlink(Name) of
false ->
dir_3(Name, Dir, Regexp, Env);
true when Env#dir.follow_links =:= true ->
dir_3(Name, Dir, Regexp, Env);
_ ->
ok
end;
_ ->
ok
end.
dir_3(Name, Dir, Regexp, Env) ->
Dir1 = filename:join(Dir, Name),
verbose("tidying directory `~ts'.", [Dir1], Env#dir.options),
dir_1(Dir1, Regexp, Env).
dir_4(File, Regexp, Env) ->
case re:run(File, Regexp) of
{match, _} ->
Opts = [{outfile, File}, {dir, ""} | Env#dir.options],
case catch file(File, Opts) of
{'EXIT', Value} ->
warn("error tidying `~ts'.~n~p", [File,Value], Opts);
_ ->
ok
end;
nomatch ->
ok
end.
file__defaults() ->
[{backup_suffix, ?DEFAULT_BACKUP_SUFFIX},
backups,
{dir, ?DEFAULT_DIR},
{printer, default_printer()},
{quiet, false},
{verbose, false}].
default_printer() ->
fun erl_prettypr:format/2.
%% =====================================================================
%% @spec file(Name) -> ok
%% @equiv file(Name, [])
-spec file(file:filename()) -> 'ok'.
file(Name) ->
file(Name, []).
%% =====================================================================
%% @spec file(Name::filename(), Options::[term()]) -> ok
%%
%% @doc Tidies an Erlang source code file.
%%
%% Available options are:
%% <dl>
%% <dt>{backup_suffix, string()}</dt>
%%
%% <dd>Specifies the file name suffix to be used when a backup
%% file is created; the default value is `".bak"'
%% (cf. the `backups' option).</dd>
%%
%% <dt>{backups, boolean()}</dt>
%%
%% <dd>If the value is `true', existing files will be
%% renamed before new files are opened for writing. The new
%% names are formed by appending the string given by the
%% `backup_suffix' option to the original name. The
%% default value is `true'.</dd>
%%
%% <dt>{dir, filename()}</dt>
%%
%% <dd>Specifies the name of the directory in which the output
%% file is to be written. By default, the current directory is
%% used. If the value is an empty string, the current directory
%% is used. </dd>
%%
%% <dt>{outfile, filename()}</dt>
%%
%% <dd>Specifies the name of the file (without suffix) to which
%% the resulting source code is to be written. If this option is
%% not specified, the `Name' argument is used.</dd>
%%
%% <dt>{printer, Function}</dt>
%% <dd><ul>
%% <li>`Function = (syntaxTree(), [term()]) -> string()'</li>
%% </ul>
%%
%% Specifies a function for prettyprinting Erlang syntax trees.
%% This is used for outputting the resulting module definition.
%% The function is assumed to return formatted text for the given
%% syntax tree, and should raise an exception if an error occurs.
%% The default formatting function calls
%% `erl_prettypr:format/2'.</dd>
%%
%% <dt>{test, boolean()}</dt>
%%
%% <dd>If the value is `true', no files will be modified; this
%% is typically most useful if the `verbose' flag is enabled, to
%% generate reports about the program files without affecting
%% them. The default value is `false'.</dd>
%%
%% <dt>{stdout, boolean()}</dt>
%%
%% <dd>If the value is `true', instead of the file being written
%% to disk it will be printed to stdout. The default value is
%% `false'.</dd>
%%
%% </dl>
%%
%% See the function `module/2' for further options.
%%
%% @see erl_prettypr:format/2
%% @see module/2
-spec file(file:filename(), options()) -> 'ok'.
file(Name, Opts) ->
Parent = self(),
Child = spawn_link(fun () -> file_1(Parent, Name, Opts) end),
receive
{Child, ok} ->
ok;
{Child, {error, Reason}} ->
exit(Reason);
{'EXIT', Child, Reason} ->
exit(Reason)
end.
file_1(Parent, Name, Opts) ->
try file_2(Name, Opts) of
_ ->
Parent ! {self(), ok}
catch
throw:syntax_error -> % ignore syntax errors
Parent ! {self(), ok};
error:Reason ->
Parent ! {self(), {error, Reason}}
end.
file_2(Name, Opts) ->
Opts1 = Opts ++ file__defaults(),
Forms = read_module(Name, Opts1),
Comments = erl_comment_scan:file(Name),
Forms1 = erl_recomment:recomment_forms(Forms, Comments),
Tree = module(Forms1, [{file, Name} | Opts1]),
case proplists:get_bool(test, Opts1) of
true ->
ok;
false ->
case proplists:get_bool(stdout, Opts1) of
true ->
print_module(Tree, Opts1),
ok;
false ->
write_module(Tree, Name, Opts1),
ok
end
end.
read_module(Name, Opts) ->
verbose("reading module `~ts'.", [filename(Name)], Opts),
case epp_dodger:parse_file(Name, [no_fail]) of
{ok, Forms} ->
check_forms(Forms, Name),
Forms;
{error, R} ->
error_read_file(Name),
exit({error, R})
end.
check_forms(Fs, Name) ->
Fun = fun (F) ->
case erl_syntax:type(F) of
error_marker ->
S = case erl_syntax:error_marker_info(F) of
{_, M, D} ->
M:format_error(D);
_ ->
"unknown error"
end,
report_error({Name, erl_syntax:get_pos(F),
"\n ~ts"}, [S]),
exit(error);
_ ->
ok
end
end,
lists:foreach(Fun, Fs).
%% Create the target directory and make a backup file if necessary,
%% then open the file, output the text and close the file
%% safely. Returns the file name.
write_module(Tree, Name, Opts) ->
Name1 = proplists:get_value(outfile, Opts, filename(Name)),
Dir = filename(proplists:get_value(dir, Opts, "")),
File = if Dir =:= "" ->
Name1;
true ->
case file_type(Dir) of
{value, directory} ->
ok;
{value, _} ->
report_error("`~ts' is not a directory.",
[filename(Dir)]),
exit(error);
none ->
case file:make_dir(Dir) of
ok ->
verbose("created directory `~ts'.",
[filename(Dir)], Opts),
ok;
E ->
report_error("failed to create "
"directory `~ts'.",
[filename(Dir)]),
exit({make_dir, E})
end
end,
filename(filename:join(Dir, Name1))
end,
Encoding = [{encoding,Enc} || Enc <- [epp:read_encoding(Name)],
Enc =/= none],
case proplists:get_bool(backups, Opts) of
true ->
backup_file(File, Opts);
false ->
ok
end,
Printer = proplists:get_value(printer, Opts),
FD = open_output_file(File, Encoding),
verbose("writing to file `~ts'.", [File], Opts),
V = (catch {ok, output(FD, Printer, Tree, Opts++Encoding)}),
ok = file:close(FD),
case V of
{ok, _} ->
File;
{'EXIT', R} ->
error_write_file(File),
exit(R);
R ->
error_write_file(File),
throw(R)
end.
print_module(Tree, Opts) ->
Printer = proplists:get_value(printer, Opts),
io:put_chars(Printer(Tree, Opts)).
output(FD, Printer, Tree, Opts) ->
io:put_chars(FD, Printer(Tree, Opts)),
io:nl(FD).
%% file_type(file:filename()) -> {value, Type} | none
file_type(Name) ->
file_type(Name, false).
is_symlink(Name) ->
file_type(Name, true) =:= {value, symlink}.
file_type(Name, Links) ->
V = case Links of
true ->
catch file:read_link_info(Name);
false ->
catch file:read_file_info(Name)
end,
case V of
{ok, Env} ->
{value, Env#file_info.type};
{error, enoent} ->
none;
{error, R} ->
error_read_file(Name),
exit({error, R});
{'EXIT', R} ->
error_read_file(Name),
exit(R);
R ->
error_read_file(Name),
throw(R)
end.
open_output_file(FName, Options) ->
case catch file:open(FName, [write]++Options) of
{ok, FD} ->
FD;
{error, R} ->
error_open_output(FName),
exit({error, R});
{'EXIT', R} ->
error_open_output(FName),
exit(R);
R ->
error_open_output(FName),
exit(R)
end.
%% If the file exists, rename it by appending the given suffix to the
%% file name.
backup_file(Name, Opts) ->
case file_type(Name) of
{value, regular} ->
backup_file_1(Name, Opts);
{value, _} ->
error_backup_file(Name),
exit(error);
none ->
ok
end.
%% The file should exist and be a regular file here.
backup_file_1(Name, Opts) ->
Suffix = proplists:get_value(backup_suffix, Opts, ""),
Dest = filename:join(filename:dirname(Name),
filename:basename(Name) ++ Suffix),
case catch file:rename(Name, Dest) of
ok ->
verbose("made backup of file `~ts'.", [Name], Opts);
{error, R} ->
error_backup_file(Name),
exit({error, R});
{'EXIT', R} ->
error_backup_file(Name),
exit(R);
R ->
error_backup_file(Name),
throw(R)
end.
%% =====================================================================
%% @spec module(Forms) -> syntaxTree()
%% @equiv module(Forms, [])
-spec module(erl_syntax:forms()) -> erl_syntax:syntaxTree().
module(Forms) ->
module(Forms, []).
%% =====================================================================
%% @spec module(Forms, Options::[term()]) -> syntaxTree()
%%
%% Forms = syntaxTree() | [syntaxTree()]
%%
%% @doc Tidies a syntax tree representation of a module
%% definition. The given `Forms' may be either a single
%% syntax tree of type `form_list', or a list of syntax
%% trees representing "program forms". In either case,
%% `Forms' must represent a single complete module
%% definition. The returned syntax tree has type
%% `form_list' and represents a tidied-up version of the
%% same source code.
%%
%% Available options are:
%% <dl>
%% <dt>{auto_export_vars, boolean()}</dt>
%%
%% <dd>If the value is `true', all matches
%% "`{V1, ..., Vn} = E'" where `E' is a
%% case-, if- or receive-expression whose branches all return
%% n-tuples (or explicitly throw exceptions) will be rewritten
%% to bind and export the variables `V1', ...,
%% `Vn' directly. The default value is `false'.
%%
%% For example:
%% <pre>
%% {X, Y} = case ... of
%% ... -> {17, foo()};
%% ... -> {42, bar()}
%% end
%% </pre>
%% will be rewritten to:
%% <pre>
%% case ... of
%% ... -> X = 17, Y = foo(), {X, Y};
%% ... -> X = 42, Y = bar(), {X, Y}
%% end
%% </pre></dd>
%%
%% <dt>{auto_list_comp, boolean()}</dt>
%%
%% <dd>If the value is `true', calls to `lists:map/2' and
%% `lists:filter/2' will be rewritten using list comprehensions.
%% The default value is `true'.</dd>
%%
%% <dt>{file, string()}</dt>
%%
%% <dd>Specifies the name of the file from which the source code
%% was taken. This is only used for generation of error
%% reports. The default value is the empty string.</dd>
%%
%% <dt>{idem, boolean()}</dt>
%%
%% <dd>If the value is `true', all options that affect how the
%% code is modified are set to "no changes". For example, to
%% only update guard tests, and nothing else, use the options
%% `[new_guard_tests, idem]'. (Recall that options closer to the
%% beginning of the list have higher precedence.)</dd>
%%
%% <dt>{keep_unused, boolean()}</dt>
%%
%% <dd>If the value is `true', unused functions will
%% not be removed from the code. The default value is
%% `false'.</dd>
%%
%% <dt>{new_guard_tests, boolean()}</dt>
%%
%% <dd>If the value is `true', guard tests will be updated to
%% use the new names, e.g. "`is_integer(X)'" instead of
%% "`integer(X)'". The default value is `true'. See also
%% `old_guard_tests'.</dd>
%%
%% <dt>{no_imports, boolean()}</dt>
%%
%% <dd>If the value is `true', all import statements will be
%% removed and calls to imported functions will be expanded to
%% explicit remote calls. The default value is `false'.</dd>
%%
%% <dt>{old_guard_tests, boolean()}</dt>
%%
%% <dd>If the value is `true', guard tests will be changed to
%% use the old names instead of the new ones, e.g.
%% "`integer(X)'" instead of "`is_integer(X)'". The default
%% value is `false'. This option overrides the `new_guard_tests'
%% option.</dd>
%%
%% <dt>{quiet, boolean()}</dt>
%%
%% <dd>If the value is `true', all information
%% messages and warning messages will be suppressed. The default
%% value is `false'.</dd>
%%
%% <dt>{rename, [{{atom(), atom(), integer()},
%% {atom(), atom()}}]}</dt>
%%
%% <dd>The value is a list of pairs, associating tuples
%% `{Module, Name, Arity}' with tuples `{NewModule, NewName}',
%% specifying renamings of calls to remote functions. By
%% default, the value is the empty list.
%%
%% The renaming affects only remote calls (also when
%% disguised by import declarations); local calls within a
%% module are not affected, and no function definitions are
%% renamed. Since the arity cannot change, the new name is
%% represented by `{NewModule, NewName}' only. Only
%% calls matching the specified arity will match; multiple
%% entries are necessary for renaming calls to functions that
%% have the same module and function name, but different
%% arities.
%%
%% This option can also be used to override the default
%% renaming of calls which use obsolete function names.</dd>
%%
%% <dt>{verbose, boolean()}</dt>
%%
%% <dd>If the value is `true', progress messages will be output
%% while the program is running, unless the `quiet' option is
%% `true'. The default value is `false'.</dd>
%%
%% </dl>
-spec module(erl_syntax:forms(), [term()]) -> erl_syntax:syntaxTree().
module(Forms, Opts) when is_list(Forms) ->
module(erl_syntax:form_list(Forms), Opts);
module(Forms, Opts) ->
Opts1 = proplists:expand(module__expansions(), Opts)
++ module__defaults(),
File = proplists:get_value(file, Opts1, ""),
Forms1 = erl_syntax:flatten_form_list(Forms),
module_1(Forms1, File, Opts1).
module__defaults() ->
[{auto_export_vars, false},
{auto_list_comp, true},
{keep_unused, false},
{new_guard_tests, true},
{no_imports, false},
{old_guard_tests, false},
{quiet, false},
{verbose, false}].
module__expansions() ->
[{idem, [{auto_export_vars, false},
{auto_list_comp, false},
{keep_unused, true},
{new_guard_tests, false},
{no_imports, false},
{old_guard_tests, false}]}].
module_1(Forms, File, Opts) ->
Info = analyze_forms(Forms, File),
Module = get_module_name(Info, File),
Attrs = get_module_attributes(Info),
Exports = get_module_exports(Info),
Imports = get_module_imports(Info),
Opts1 = check_imports(Imports, Opts, File),
Fs = erl_syntax:form_list_elements(Forms),
{Names, Defs} = collect_functions(Fs),
Exports1 = check_export_all(Attrs, Names, Exports),
Roots = ordsets:union(ordsets:from_list(Exports1),
hidden_uses(Fs, Imports)),
{Names1, Used, Imported, Defs1} = visit_used(Names, Defs, Roots,
Imports, Module,
Opts1),
Fs1 = update_forms(Fs, Defs1, Imported, Opts1),
Fs2 = filter_forms(Fs1, Names1, Used, Opts1),
rewrite(Forms, erl_syntax:form_list(Fs2)).
analyze_forms(Forms, File) ->
case catch {ok, erl_syntax_lib:analyze_forms(Forms)} of
{ok, L1} ->
L1;
syntax_error ->
report_error({File, 0, "syntax error."}),
throw(syntax_error);
{'EXIT', R} ->
exit(R);
R ->
throw(R)
end.
-spec get_module_name([erl_syntax_lib:info_pair()], string()) -> atom().
get_module_name(List, File) ->
case lists:keyfind(module, 1, List) of
{module, M} ->
M;
_ ->
report_error({File, 0,
"cannot determine module name."}),
exit(error)
end.
get_module_attributes(List) ->
case lists:keyfind(attributes, 1, List) of
{attributes, As} ->
As;
_ ->
[]
end.
-spec get_module_exports([erl_syntax_lib:info_pair()]) -> [{atom(), arity()}].
get_module_exports(List) ->
case lists:keyfind(exports, 1, List) of
{exports, Es} ->
Es;
_ ->
[]
end.
-spec get_module_imports([erl_syntax_lib:info_pair()]) -> [{atom(), atom()}].
get_module_imports(List) ->
case lists:keyfind(imports, 1, List) of
{imports, Is} ->
flatten_imports(Is);
_ ->
[]
end.
compile_attrs(As) ->
lists:append([if is_list(T) -> T; true -> [T] end
|| {compile, T} <- As]).
-spec flatten_imports([{atom(), [atom()]}]) -> [{atom(), atom()}].
flatten_imports(Is) ->
[{F, M} || {M, Fs} <- Is, F <- Fs].
check_imports(Is, Opts, File) ->
case check_imports_1(lists:sort(Is)) of
true ->
Opts;
false ->
case proplists:get_bool(no_imports, Opts) of
true ->
warn({File, 0,
"conflicting import declarations - "
"will not expand imports."},
[], Opts),
%% prevent expansion of imports
[{no_imports, false} | Opts];
false ->
Opts
end
end.
-spec check_imports_1([{atom(), atom()}]) -> boolean().
check_imports_1([{F, M1}, {F, M2} | _Is]) when M1 =/= M2 ->
false;
check_imports_1([_ | Is]) ->
check_imports_1(Is);
check_imports_1([]) ->
true.
check_export_all(Attrs, Names, Exports) ->
case lists:member(export_all, compile_attrs(Attrs)) of
true ->
Exports ++ sets:to_list(Names);
false ->
Exports
end.
filter_forms(Fs, Names, Used, Opts) ->
Keep = case proplists:get_bool(keep_unused, Opts) of
true ->
Names;
false ->
Used
end,
[F || F <- Fs, keep_form(F, Keep, Opts)].
keep_form(Form, Used, Opts) ->
case erl_syntax:type(Form) of
function ->
N = erl_syntax_lib:analyze_function(Form),
case sets:is_element(N, Used) of
false ->
{F, A} = N,
File = proplists:get_value(file, Opts, ""),
report({File, erl_syntax:get_pos(Form),
"removing unused function `~w/~w'."},
[F, A], Opts),
false;
true ->
true
end;
attribute ->
case erl_syntax_lib:analyze_attribute(Form) of
{file, _} ->
false;
_ ->
true
end;
error_marker ->
false;
warning_marker ->
false;
eof_marker ->
false;
_ ->
true
end.
collect_functions(Forms) ->
lists:foldl(
fun (F, {Names, Defs}) ->
case erl_syntax:type(F) of
function ->
N = erl_syntax_lib:analyze_function(F),
{sets:add_element(N, Names),
dict:store(N, {F, []}, Defs)};
_ ->
{Names, Defs}
end
end,
{sets:new(), dict:new()},
Forms).
update_forms([F | Fs], Defs, Imports, Opts) ->
case erl_syntax:type(F) of
function ->
N = erl_syntax_lib:analyze_function(F),
{F1, Fs1} = dict:fetch(N, Defs),
[F1 | lists:reverse(Fs1)] ++ update_forms(Fs, Defs, Imports,
Opts);
attribute ->
[update_attribute(F, Imports, Opts)
| update_forms(Fs, Defs, Imports, Opts)];
_ ->
[F | update_forms(Fs, Defs, Imports, Opts)]
end;
update_forms([], _, _, _) ->
[].
update_attribute(F, Imports, Opts) ->
case erl_syntax_lib:analyze_attribute(F) of
{import, {M, Ns}} ->
Ns1 = ordsets:from_list([N || N <- Ns,
sets:is_element(N, Imports)]),
case ordsets:subtract(ordsets:from_list(Ns), Ns1) of
[] ->
ok;
Names ->
File = proplists:get_value(file, Opts, ""),
report({File, erl_syntax:get_pos(F),
"removing unused imports:~s"},
[[io_lib:fwrite("\n\t`~w:~w/~w'", [M, N, A])
|| {N, A} <- Names]], Opts)
end,
Is = [make_fname(N) || N <- Ns1],
if Is =:= [] ->
%% This will be filtered out later.
erl_syntax:warning_marker(deleted);
true ->
F1 = erl_syntax:attribute(erl_syntax:atom(import),
[erl_syntax:atom(M),
erl_syntax:list(Is)]),
rewrite(F, F1)
end;
{export, Ns} ->
Es = [make_fname(N) || N <- ordsets:from_list(Ns)],
F1 = erl_syntax:attribute(erl_syntax:atom(export),
[erl_syntax:list(Es)]),
rewrite(F, F1);
_ ->
F
end.
make_fname({F, A}) ->
erl_syntax:arity_qualifier(erl_syntax:atom(F),
erl_syntax:integer(A)).
hidden_uses(Fs, Imports) ->
Used = lists:foldl(fun (F, S) ->
case erl_syntax:type(F) of
attribute ->
hidden_uses_1(F, S);
_ ->
S
end
end,
[], Fs),
ordsets:subtract(Used, ordsets:from_list([F || {F, _M} <- Imports])).
hidden_uses_1(Tree, Used) ->
erl_syntax_lib:fold(fun hidden_uses_2/2, Used, Tree).
hidden_uses_2(Tree, Used) ->
case erl_syntax:type(Tree) of
application ->
F = erl_syntax:application_operator(Tree),
case erl_syntax:type(F) of
atom ->
As = erl_syntax:application_arguments(Tree),
N = {erl_syntax:atom_value(F), length(As)},
case is_auto_imported(N) of
true ->
Used;
false ->
ordsets:add_element(N, Used)
end;
_ ->
Used
end;
implicit_fun ->
F = erl_syntax:implicit_fun_name(Tree),
case catch {ok, erl_syntax_lib:analyze_function_name(F)} of
{ok, {Name, Arity} = N}
when is_atom(Name), is_integer(Arity) ->
ordsets:add_element(N, Used);
_ ->
Used
end;
_ ->
Used
end.
-type fa() :: {atom(), arity()}.
-type context() :: 'guard_expr' | 'guard_test' | 'normal'.
-record(env, {file :: file:filename(),
module :: atom(),
current :: fa() | 'undefined',
imports = dict:new() :: dict:dict(atom(), atom()),
context = normal :: context(),
verbosity = 1 :: 0 | 1 | 2,
quiet = false :: boolean(),
no_imports = false :: boolean(),
spawn_funs = false :: boolean(),
auto_list_comp = true :: boolean(),
auto_export_vars = false :: boolean(),
new_guard_tests = true :: boolean(),
old_guard_tests = false :: boolean()}).
-record(st, {varc :: non_neg_integer() | 'undefined',
used = sets:new() :: sets:set({atom(), arity()}),
imported :: sets:set({atom(), arity()}),
vars :: sets:set(atom()) | 'undefined',
functions :: sets:set({atom(), arity()}),
new_forms = [] :: [erl_syntax:syntaxTree()],
rename :: dict:dict(mfa(), {atom(), atom()})}).
visit_used(Names, Defs, Roots, Imports, Module, Opts) ->
File = proplists:get_value(file, Opts, ""),
NoImports = proplists:get_bool(no_imports, Opts),
Rename = proplists:append_values(rename, Opts),
loop(Roots, sets:new(), Defs,
#env{file = File,
module = Module,
imports = dict:from_list(Imports),
verbosity = verbosity(Opts),
no_imports = NoImports,
spawn_funs = proplists:get_bool(spawn_funs, Opts),
auto_list_comp = proplists:get_bool(auto_list_comp, Opts),
auto_export_vars = proplists:get_bool(auto_export_vars,
Opts),
new_guard_tests = proplists:get_bool(new_guard_tests,
Opts),
old_guard_tests = proplists:get_bool(old_guard_tests,
Opts)},
#st{used = sets:from_list(Roots),
imported = sets:new(),
functions = Names,
rename = dict:from_list([X || {F1, F2} = X <- Rename,
is_remote_name(F1),
is_atom_pair(F2)])}).
loop([F | Work], Seen0, Defs0, Env, St0) ->
case sets:is_element(F, Seen0) of
true ->
loop(Work, Seen0, Defs0, Env, St0);
false ->
Seen1 = sets:add_element(F, Seen0),
case dict:find(F, Defs0) of
{ok, {Form, Fs}} ->
Vars = erl_syntax_lib:variables(Form),
Form1 = erl_syntax_lib:annotate_bindings(Form, []),
{Form2, St1} = visit(Form1, Env#env{current = F},
St0#st{varc = 1,
used = sets:new(),
vars = Vars,
new_forms = []}),
Fs1 = St1#st.new_forms ++ Fs,
Defs1 = dict:store(F, {Form2, Fs1}, Defs0),
Used = St1#st.used,
Work1 = sets:to_list(Used) ++ Work,
St2 = St1#st{used = sets:union(Used, St0#st.used)},
loop(Work1, Seen1, Defs1, Env, St2);
error ->
%% Quietly ignore any names that have no definition.
loop(Work, Seen1, Defs0, Env, St0)
end
end;
loop([], _, Defs, _, St) ->
{St#st.functions, St#st.used, St#st.imported, Defs}.
visit(Tree, Env, St0) ->
case erl_syntax:type(Tree) of
application ->
visit_application(Tree, Env, St0);
infix_expr ->
visit_infix_expr(Tree, Env, St0);
prefix_expr ->
visit_prefix_expr(Tree, Env, St0);
implicit_fun ->
visit_implicit_fun(Tree, Env, St0);
clause ->
visit_clause(Tree, Env, St0);
list_comp ->
visit_list_comp(Tree, Env, St0);
match_expr ->
visit_match_expr(Tree, Env, St0);
_ ->
visit_other(Tree, Env, St0)
end.
visit_other(Tree, Env, St) ->
F = fun (T, S) -> visit(T, Env, S) end,
erl_syntax_lib:mapfold_subtrees(F, St, Tree).
visit_list(Ts, Env, St0) ->
lists:mapfoldl(fun (T, S) -> visit(T, Env, S) end, St0, Ts).
visit_implicit_fun(Tree, _Env, St0) ->
F = erl_syntax:implicit_fun_name(Tree),
case catch {ok, erl_syntax_lib:analyze_function_name(F)} of
{ok, {Name, Arity} = N}
when is_atom(Name), is_integer(Arity) ->
Used = sets:add_element(N, St0#st.used),
{Tree, St0#st{used = Used}};
_ ->
%% symbolic funs do not count as uses of a function
{Tree, St0}
end.
visit_clause(Tree, Env, St0) ->
%% We do not visit the patterns (for now, anyway).
Ps = erl_syntax:clause_patterns(Tree),
{G, St1} = case erl_syntax:clause_guard(Tree) of
none ->
{none, St0};
G0 ->
visit(G0, Env#env{context = guard_test}, St0)
end,
{B, St2} = visit_list(erl_syntax:clause_body(Tree), Env, St1),
{rewrite(Tree, erl_syntax:clause(Ps, G, B)), St2}.
visit_infix_expr(Tree, #env{context = guard_test}, St0) ->
%% Detect transition from guard test to guard expression.
visit_other(Tree, #env{context = guard_expr, file = ""}, St0);
visit_infix_expr(Tree, Env, St0) ->
visit_other(Tree, Env, St0).
visit_prefix_expr(Tree, #env{context = guard_test}, St0) ->
%% Detect transition from guard test to guard expression.
visit_other(Tree, #env{context = guard_expr, file = ""}, St0);
visit_prefix_expr(Tree, Env, St0) ->
visit_other(Tree, Env, St0).
visit_application(Tree, Env, St0) ->
Env1 = case Env of
#env{context = guard_test} ->
Env#env{context = guard_expr};
_ ->
Env
end,
{F, St1} = visit(erl_syntax:application_operator(Tree), Env1, St0),
{As, St2} = visit_list(erl_syntax:application_arguments(Tree), Env1,
St1),
case erl_syntax:type(F) of
atom ->
visit_atom_application(F, As, Tree, Env, St2);
implicit_fun ->
visit_named_fun_application(F, As, Tree, Env, St2);
fun_expr ->
visit_lambda_application(F, As, Tree, Env, St2);
_ ->
visit_nonlocal_application(F, As, Tree, Env, St2)
end.
visit_application_final(F, As, Tree, St0) ->
{rewrite(Tree, erl_syntax:application(F, As)), St0}.
revisit_application(F, As, Tree, Env, St0) ->
visit(rewrite(Tree, erl_syntax:application(F, As)), Env, St0).
visit_atom_application(F, As, Tree, #env{context = guard_test} = Env,
St0) ->
N = erl_syntax:atom_value(F),
A = length(As),
N1 = case Env#env.old_guard_tests of
true ->
reverse_guard_test(N, A);
false ->
case Env#env.new_guard_tests of
true ->
rewrite_guard_test(N, A);
false ->
N
end
end,
if N1 =/= N ->
report({Env#env.file, erl_syntax:get_pos(F),
"changing guard test `~w' to `~w'."},
[N, N1], Env#env.verbosity);
true ->
ok
end,
%% No need to revisit here.
F1 = rewrite(F, erl_syntax:atom(N1)),
visit_application_final(F1, As, Tree, St0);
visit_atom_application(F, As, Tree, #env{context = guard_expr}, St0) ->
%% Atom applications in guard expressions are never local calls.
visit_application_final(F, As, Tree, St0);
visit_atom_application(F, As, Tree, Env, St0) ->
N = {erl_syntax:atom_value(F), length(As)},
case is_auto_imported(N) of
true ->
visit_bif_call(N, F, As, Tree, Env, St0);
false ->
case is_imported(N, Env) of
true ->
visit_import_application(N, F, As, Tree, Env, St0);
false ->
Used = sets:add_element(N, St0#st.used),
visit_application_final(F, As, Tree,
St0#st{used = Used})
end
end.
visit_import_application({N, A} = Name, F, As, Tree, Env, St0) ->
M = dict:fetch(Name, Env#env.imports),
Expand = case Env#env.no_imports of
true ->
true;
false ->
auto_expand_import({M, N, A}, St0)
end,
case Expand of
true ->
report({Env#env.file, erl_syntax:get_pos(F),
"expanding call to imported function `~w:~w/~w'."},
[M, N, A], Env#env.verbosity),
F1 = erl_syntax:module_qualifier(erl_syntax:atom(M),
erl_syntax:atom(N)),
revisit_application(rewrite(F, F1), As, Tree, Env, St0);
false ->
Is = sets:add_element(Name, St0#st.imported),
visit_application_final(F, As, Tree, St0#st{imported = Is})
end.
visit_bif_call({apply, 2}, F, [E, Args] = As, Tree, Env, St0) ->
case erl_syntax:is_proper_list(Args) of
true ->
report({Env#env.file, erl_syntax:get_pos(F),
"changing use of `apply/2' "
"to direct function call."},
[], Env#env.verbosity),
As1 = erl_syntax:list_elements(Args),
revisit_application(E, As1, Tree, Env, St0);
false ->
visit_application_final(F, As, Tree, St0)
end;
visit_bif_call({apply, 3}, F, [M, N, Args] = As, Tree, Env, St0) ->
case erl_syntax:is_proper_list(Args) of
true ->
report({Env#env.file, erl_syntax:get_pos(F),
"changing use of `apply/3' "
"to direct remote call."},
[], Env#env.verbosity),
F1 = rewrite(F, erl_syntax:module_qualifier(M, N)),
As1 = erl_syntax:list_elements(Args),
visit_nonlocal_application(F1, As1, Tree, Env, St0);
false ->
visit_application_final(F, As, Tree, St0)
end;
visit_bif_call({spawn, 3} = N, F, [_, _, _] = As, Tree, Env, St0) ->
visit_spawn_call(N, F, [], As, Tree, Env, St0);
visit_bif_call({spawn_link, 3} = N, F, [_, _, _] = As, Tree, Env,
St0) ->
visit_spawn_call(N, F, [], As, Tree, Env, St0);
visit_bif_call({spawn, 4} = N, F, [A | [_, _, _] = As], Tree, Env,
St0) ->
visit_spawn_call(N, F, [A], As, Tree, Env, St0);
visit_bif_call({spawn_link, 4} = N, F, [A | [_, _, _] = As], Tree, Env,
St0) ->
visit_spawn_call(N, F, [A], As, Tree, Env, St0);
visit_bif_call(_, F, As, Tree, _Env, St0) ->
visit_application_final(F, As, Tree, St0).
visit_spawn_call({N, A}, F, Ps, [A1, A2, A3] = As, Tree,
#env{spawn_funs = true} = Env, St0) ->
case erl_syntax:is_proper_list(A3) of
true ->
report({Env#env.file, erl_syntax:get_pos(F),
"changing use of `~w/~w' to `~w/~w' with a fun."},
[N, A, N, 1 + length(Ps)], Env#env.verbosity),
F1 = case erl_syntax:is_atom(A1, Env#env.module) of
true ->
A2; % calling self
false ->
clone(A1,
erl_syntax:module_qualifier(A1, A2))
end,
%% Need to do some scoping tricks here to make sure the
%% arguments are evaluated by the parent, not by the spawned
%% process.
As1 = erl_syntax:list_elements(A3),
{Vs, St1} = new_variables(length(As1), St0),
E1 = clone(F1, erl_syntax:application(F1, Vs)),
C1 = clone(E1, erl_syntax:clause([], [E1])),
E2 = clone(C1, erl_syntax:fun_expr([C1])),
C2 = clone(E2, erl_syntax:clause(Vs, [], [E2])),
E3 = clone(C2, erl_syntax:fun_expr([C2])),
E4 = clone(E3, erl_syntax:application(E3, As1)),
E5 = erl_syntax_lib:annotate_bindings(E4, get_env(A1)),
{E6, St2} = visit(E5, Env, St1),
F2 = rewrite(F, erl_syntax:atom(N)),
visit_nonlocal_application(F2, Ps ++ [E6], Tree, Env, St2);
false ->
visit_application_final(F, Ps ++ As, Tree, St0)
end;
visit_spawn_call(_, F, Ps, As, Tree, _Env, St0) ->
visit_application_final(F, Ps ++ As, Tree, St0).
visit_named_fun_application(F, As, Tree, Env, St0) ->
Name = erl_syntax:implicit_fun_name(F),
case catch {ok, erl_syntax_lib:analyze_function_name(Name)} of
{ok, {A, N}} when is_atom(A), is_integer(N), N =:= length(As) ->
case is_nonlocal({A, N}, Env) of
true ->
%% Making this a direct call would be an error.
visit_application_final(F, As, Tree, St0);
false ->
report({Env#env.file, erl_syntax:get_pos(F),
"changing application of implicit fun "
"to direct local call."},
[], Env#env.verbosity),
Used = sets:add_element({A, N}, St0#st.used),
F1 = rewrite(F, erl_syntax:atom(A)),
revisit_application(F1, As, Tree, Env,
St0#st{used = Used})
end;
_ ->
visit_application_final(F, As, Tree, St0)
end.
visit_lambda_application(F, As, Tree, Env, St0) ->
A = erl_syntax:fun_expr_arity(F),
case A =:= length(As) of
true ->
report({Env#env.file, erl_syntax:get_pos(F),
"changing application of fun-expression "
"to local function call."},
[], Env#env.verbosity),
{Base, _} = Env#env.current,
Free = [erl_syntax:variable(V) || V <- get_free_vars(F)],
N = length(Free),
A1 = A + N,
{Name, St1} = new_fname({Base, A1}, St0),
Cs = augment_clauses(erl_syntax:fun_expr_clauses(F), Free),
F1 = erl_syntax:atom(Name),
New = rewrite(F, erl_syntax:function(F1, Cs)),
Used = sets:add_element({Name, A1}, St1#st.used),
Forms = [New | St1#st.new_forms],
St2 = St1#st{new_forms = Forms, used = Used},
visit_application_final(F1, As ++ Free, Tree, St2);
false ->
warn({Env#env.file, erl_syntax:get_pos(F),
"arity mismatch in fun-expression application."},
[], Env#env.verbosity),
visit_application_final(F, As, Tree, St0)
end.
augment_clauses(Cs, Vs) ->
[begin
Ps = erl_syntax:clause_patterns(C),
G = erl_syntax:clause_guard(C),
Es = erl_syntax:clause_body(C),
rewrite(C, erl_syntax:clause(Ps ++ Vs, G, Es))
end
|| C <- Cs].
visit_nonlocal_application(F, As, Tree, Env, St0) ->
case erl_syntax:type(F) of
tuple ->
case erl_syntax:tuple_elements(F) of
[X1, X2] ->
report({Env#env.file, erl_syntax:get_pos(F),
"changing application of 2-tuple "
"to direct remote call."},
[], Env#env.verbosity),
F1 = erl_syntax:module_qualifier(X1, X2),
revisit_application(rewrite(F, F1), As, Tree, Env,
St0);
_ ->
visit_application_final(F, As, Tree, St0)
end;
module_qualifier ->
case catch {ok, erl_syntax_lib:analyze_function_name(F)} of
{ok, {M, N}} when is_atom(M), is_atom(N) ->
visit_remote_application({M, N, length(As)}, F, As,
Tree, Env, St0);
_ ->
visit_application_final(F, As, Tree, St0)
end;
_ ->
visit_application_final(F, As, Tree, St0)
end.
%% --- lists:append/2 and lists:subtract/2 ---
visit_remote_application({lists, append, 2}, F, [A1, A2], Tree, Env,
St0) ->
report({Env#env.file, erl_syntax:get_pos(F),
"replacing call to `lists:append/2' "
"with the `++' operator."},
[], Env#env.verbosity),
Tree1 = erl_syntax:infix_expr(A1, erl_syntax:operator('++'), A2),
visit(rewrite(Tree, Tree1), Env, St0);
visit_remote_application({lists, subtract, 2}, F, [A1, A2], Tree, Env,
St0) ->
report({Env#env.file, erl_syntax:get_pos(F),
"replacing call to `lists:subtract/2' "
"with the `--' operator."},
[], Env#env.verbosity),
Tree1 = erl_syntax:infix_expr(A1, erl_syntax:operator('--'), A2),
visit(rewrite(Tree, Tree1), Env, St0);
%% --- lists:map/2 and lists:filter/2 ---
visit_remote_application({lists, filter, 2}, F, [A1, A2] = As, Tree,
Env, St0) ->
case Env#env.auto_list_comp
and (erl_syntax:type(A1) =/= variable)
and (get_var_exports(A1) =:= [])
and (get_var_exports(A2) =:= []) of
true ->
report({Env#env.file, erl_syntax:get_pos(F),
"replacing call to `lists:filter/2' "
"with a list comprehension."},
[], Env#env.verbosity),
{V, St1} = new_variable(St0),
G = clone(A2, erl_syntax:generator(V, A2)),
T = clone(A1, erl_syntax:application(A1, [V])),
L = erl_syntax:list_comp(V, [G, T]),
L1 = erl_syntax_lib:annotate_bindings(L, get_env(Tree)),
visit(rewrite(Tree, L1), Env, St1);
false ->
visit_application_final(F, As, Tree, St0)
end;
visit_remote_application({lists, map, 2}, F, [A1, A2] = As, Tree, Env,
St0) ->
case Env#env.auto_list_comp
and (erl_syntax:type(A1) =/= variable)
and (get_var_exports(A1) =:= [])
and (get_var_exports(A2) =:= []) of
true ->
report({Env#env.file, erl_syntax:get_pos(F),
"replacing call to `lists:map/2' "
"with a list comprehension."},
[], Env#env.verbosity),
{V, St1} = new_variable(St0),
T = clone(A1, erl_syntax:application(A1, [V])),
G = clone(A2, erl_syntax:generator(V, A2)),
L = erl_syntax:list_comp(T, [G]),
L1 = erl_syntax_lib:annotate_bindings(L, get_env(Tree)),
visit(rewrite(Tree, L1), Env, St1);
false ->
visit_application_final(F, As, Tree, St0)
end;
%% --- all other functions ---
visit_remote_application({M, N, A} = Name, F, As, Tree, Env, St) ->
case is_auto_imported(Name) of
true ->
%% We don't remove the qualifier - it might be there for the
%% sake of clarity.
visit_bif_call({N, A}, F, As, Tree, Env, St);
false ->
case rename_remote_call(Name, St) of
{M1, N1} ->
report({Env#env.file, erl_syntax:get_pos(F),
"updating obsolete call to `~w:~w/~w' "
"to use `~w:~w/~w' instead."},
[M, N, A, M1, N1, A], Env#env.verbosity),
M2 = erl_syntax:atom(M1),
N2 = erl_syntax:atom(N1),
F1 = erl_syntax:module_qualifier(M2, N2),
revisit_application(rewrite(F, F1), As, Tree, Env,
St);
false ->
visit_application_final(F, As, Tree, St)
end
end.
-spec auto_expand_import(mfa(), #st{}) -> boolean().
auto_expand_import({lists, append, 2}, _St) -> true;
auto_expand_import({lists, subtract, 2}, _St) -> true;
auto_expand_import({lists, filter, 2}, _St) -> true;
auto_expand_import({lists, map, 2}, _St) -> true;
auto_expand_import(Name, St) ->
case is_auto_imported(Name) of
true ->
true;
false ->
rename_remote_call(Name, St) =/= false
end.
visit_list_comp(Tree, Env, St0) ->
Es = erl_syntax:list_comp_body(Tree),
{Es1, St1} = visit_list_comp_body(Es, Env, St0),
{T, St2} = visit(erl_syntax:list_comp_template(Tree), Env, St1),
{rewrite(Tree, erl_syntax:list_comp(T, Es1)), St2}.
visit_list_comp_body_join(Env) ->
fun (E, St0) ->
case is_generator(E) of
true ->
visit_generator(E, Env, St0);
false ->
visit_filter(E, Env, St0)
end
end.
visit_list_comp_body(Es, Env, St0) ->
lists:mapfoldl(visit_list_comp_body_join(Env), St0, Es).
%% 'visit_filter' also handles uninteresting generators.
visit_filter(E, Env, St0) ->
visit(E, Env, St0).
%% "interesting" generators have the form V <- [V || ...]; this can be
%% unfolded as long as no bindings become erroneously shadowed.
visit_generator(G, Env, St0) ->
P = erl_syntax:generator_pattern(G),
case erl_syntax:type(P) of
variable ->
B = erl_syntax:generator_body(G),
case erl_syntax:type(B) of
list_comp ->
T = erl_syntax:list_comp_template(B),
case erl_syntax:type(T) of
variable ->
visit_generator_1(G, Env, St0);
_ ->
visit_filter(G, Env, St0)
end;
_ ->
visit_filter(G, Env, St0)
end;
_ ->
visit_filter(G, Env, St0)
end.
visit_generator_1(G, Env, St0) ->
recommend({Env#env.file, erl_syntax:get_pos(G),
"unfold that this nested list comprehension can be unfolded "
"by hand to get better efficiency."},
[], Env#env.verbosity),
visit_filter(G, Env, St0).
visit_match_expr(Tree, Env, St0) ->
%% We do not visit the pattern (for now, anyway).
P = erl_syntax:match_expr_pattern(Tree),
{B, St1} = visit(erl_syntax:match_expr_body(Tree), Env, St0),
case erl_syntax:type(P) of
tuple ->
Ps = erl_syntax:tuple_elements(P),
case lists:all(fun is_variable/1, Ps) of
true ->
Vs = lists:sort([erl_syntax:variable_name(X)
|| X <- Ps]),
case ordsets:is_set(Vs) of
true ->
Xs = get_var_exports(B),
case ordsets:intersection(Vs, Xs) of
[] ->
visit_match_body(Ps, P, B, Tree,
Env, St1);
_ ->
visit_match_expr_final(P, B, Tree,
Env, St1)
end;
false ->
visit_match_expr_final(P, B, Tree, Env, St1)
end;
false ->
visit_match_expr_final(P, B, Tree, Env, St1)
end;
_ ->
visit_match_expr_final(P, B, Tree, Env, St1)
end.
visit_match_expr_final(P, B, Tree, _Env, St0) ->
{rewrite(Tree, erl_syntax:match_expr(P, B)), St0}.
visit_match_body(_Ps, P, B, Tree, #env{auto_export_vars = false} = Env,
St0) ->
visit_match_expr_final(P, B, Tree, Env, St0);
visit_match_body(Ps, P, B, Tree, Env, St0) ->
case erl_syntax:type(B) of
case_expr ->
Cs = erl_syntax:case_expr_clauses(B),
case multival_clauses(Cs, length(Ps), Ps) of
{true, Cs1} ->
report_export_vars(Env#env.file,
erl_syntax:get_pos(B),
"case", Env#env.verbosity),
A = erl_syntax:case_expr_argument(B),
Tree1 = erl_syntax:case_expr(A, Cs1),
{rewrite(Tree, Tree1), St0};
false ->
visit_match_expr_final(P, B, Tree, Env, St0)
end;
if_expr ->
Cs = erl_syntax:if_expr_clauses(B),
case multival_clauses(Cs, length(Ps), Ps) of
{true, Cs1} ->
report_export_vars(Env#env.file,
erl_syntax:get_pos(B),
"if", Env#env.verbosity),
Tree1 = erl_syntax:if_expr(Cs1),
{rewrite(Tree, Tree1), St0};
false ->
visit_match_expr_final(P, B, Tree, Env, St0)
end;
cond_expr ->
Cs = erl_syntax:cond_expr_clauses(B),
case multival_clauses(Cs, length(Ps), Ps) of
{true, Cs1} ->
report_export_vars(Env#env.file,
erl_syntax:get_pos(B),
"cond", Env#env.verbosity),
Tree1 = erl_syntax:cond_expr(Cs1),
{rewrite(Tree, Tree1), St0};
false ->
visit_match_expr_final(P, B, Tree, Env, St0)
end;
receive_expr ->
%% Handle the timeout case as an extra clause.
As = erl_syntax:receive_expr_action(B),
C = erl_syntax:clause([], As),
Cs = erl_syntax:receive_expr_clauses(B),
case multival_clauses([C | Cs], length(Ps), Ps) of
{true, [C1 | Cs1]} ->
report_export_vars(Env#env.file,
erl_syntax:get_pos(B),
"receive", Env#env.verbosity),
T = erl_syntax:receive_expr_timeout(B),
As1 = erl_syntax:clause_body(C1),
Tree1 = erl_syntax:receive_expr(Cs1, T, As1),
{rewrite(Tree, Tree1), St0};
false ->
visit_match_expr_final(P, B, Tree, Env, St0)
end;
_ ->
visit_match_expr_final(P, B, Tree, Env, St0)
end.
multival_clauses(Cs, N, Vs) ->
multival_clauses(Cs, N, Vs, []).
multival_clauses([C | Cs], N, Vs, Cs1) ->
case erl_syntax:clause_body(C) of
[] ->
false;
Es ->
E = lists:last(Es),
case erl_syntax:type(E) of
tuple ->
Ts = erl_syntax:tuple_elements(E),
if length(Ts) =:= N ->
Bs = make_matches(E, Vs, Ts),
Es1 = replace_last(Es, Bs),
Ps = erl_syntax:clause_patterns(C),
G = erl_syntax:clause_guard(C),
C1 = erl_syntax:clause(Ps, G, Es1),
multival_clauses(Cs, N, Vs,
[rewrite(C, C1) | Cs1]);
true ->
false
end;
_ ->
case erl_syntax_lib:is_fail_expr(E) of
true ->
%% We must add dummy bindings here so we
%% don't introduce compilation errors due to
%% "unsafe" variable exports.
Bs = make_matches(Vs,
erl_syntax:atom(false)),
Es1 = replace_last(Es, Bs ++ [E]),
Ps = erl_syntax:clause_patterns(C),
G = erl_syntax:clause_guard(C),
C1 = erl_syntax:clause(Ps, G, Es1),
multival_clauses(Cs, N, Vs,
[rewrite(C, C1) | Cs1]);
false ->
false
end
end
end;
multival_clauses([], _N, _Vs, Cs) ->
{true, lists:reverse(Cs)}.
make_matches(E, Vs, Ts) ->
case make_matches(Vs, Ts) of
[] ->
[];
[B | Bs] ->
[rewrite(E, B) | Bs] % preserve comments on E (but not B)
end.
make_matches([V | Vs], [T | Ts]) ->
[erl_syntax:match_expr(V, T) | make_matches(Vs, Ts)];
make_matches([V | Vs], T) when T =/= [] ->
[erl_syntax:match_expr(V, T) | make_matches(Vs, T)];
make_matches([], _) ->
[].
rename_remote_call(F, St) ->
case dict:find(F, St#st.rename) of
error ->
rename_remote_call_1(F);
{ok, F1} -> F1
end.
-spec rename_remote_call_1(mfa()) -> {atom(), atom()} | 'false'.
rename_remote_call_1({dict, dict_to_list, 1}) -> {dict, to_list};
rename_remote_call_1({dict, list_to_dict, 1}) -> {dict, from_list};
rename_remote_call_1({erl_eval, arg_list, 2}) -> {erl_eval, expr_list};
rename_remote_call_1({erl_eval, arg_list, 3}) -> {erl_eval, expr_list};
rename_remote_call_1({erl_eval, seq, 2}) -> {erl_eval, exprs};
rename_remote_call_1({erl_eval, seq, 3}) -> {erl_eval, exprs};
rename_remote_call_1({erl_pp, seq, 1}) -> {erl_eval, seq};
rename_remote_call_1({erl_pp, seq, 2}) -> {erl_eval, seq};
rename_remote_call_1({erlang, info, 1}) -> {erlang, system_info};
rename_remote_call_1({io, parse_erl_seq, 1}) -> {io, parse_erl_exprs};
rename_remote_call_1({io, parse_erl_seq, 2}) -> {io, parse_erl_exprs};
rename_remote_call_1({io, parse_erl_seq, 3}) -> {io, parse_erl_exprs};
rename_remote_call_1({io, scan_erl_seq, 1}) -> {io, scan_erl_exprs};
rename_remote_call_1({io, scan_erl_seq, 2}) -> {io, scan_erl_exprs};
rename_remote_call_1({io, scan_erl_seq, 3}) -> {io, scan_erl_exprs};
rename_remote_call_1({io_lib, reserved_word, 1}) -> {erl_scan, reserved_word};
rename_remote_call_1({io_lib, scan, 1}) -> {erl_scan, string};
rename_remote_call_1({io_lib, scan, 2}) -> {erl_scan, string};
rename_remote_call_1({io_lib, scan, 3}) -> {erl_scan, tokens};
rename_remote_call_1({orddict, dict_to_list, 1}) -> {orddict, to_list};
rename_remote_call_1({orddict, list_to_dict, 1}) -> {orddict, from_list};
rename_remote_call_1({ordsets, list_to_set, 1}) -> {ordsets, from_list};
rename_remote_call_1({ordsets, new_set, 0}) -> {ordsets, new};
rename_remote_call_1({ordsets, set_to_list, 1}) -> {ordsets, to_list};
rename_remote_call_1({ordsets, subset, 2}) -> {ordsets, is_subset};
rename_remote_call_1({sets, list_to_set, 1}) -> {sets, from_list};
rename_remote_call_1({sets, new_set, 0}) -> {sets, new};
rename_remote_call_1({sets, set_to_list, 1}) -> {sets, to_list};
rename_remote_call_1({sets, subset, 2}) -> {sets, is_subset};
rename_remote_call_1({string, index, 2}) -> {string, str};
rename_remote_call_1({unix, cmd, 1}) -> {os, cmd};
rename_remote_call_1(_) -> false.
-spec rewrite_guard_test(atom(), arity()) -> atom().
rewrite_guard_test(atom, 1) -> is_atom;
rewrite_guard_test(binary, 1) -> is_binary;
rewrite_guard_test(constant, 1) -> is_constant;
rewrite_guard_test(float, 1) -> is_float;
rewrite_guard_test(function, 1) -> is_function;
rewrite_guard_test(function, 2) -> is_function;
rewrite_guard_test(integer, 1) -> is_integer;
rewrite_guard_test(list, 1) -> is_list;
rewrite_guard_test(number, 1) -> is_number;
rewrite_guard_test(pid, 1) -> is_pid;
rewrite_guard_test(port, 1) -> is_port;
rewrite_guard_test(reference, 1) -> is_reference;
rewrite_guard_test(tuple, 1) -> is_tuple;
rewrite_guard_test(record, 2) -> is_record;
rewrite_guard_test(record, 3) -> is_record;
rewrite_guard_test(N, _A) -> N.
-spec reverse_guard_test(atom(), arity()) -> atom().
reverse_guard_test(is_atom, 1) -> atom;
reverse_guard_test(is_binary, 1) -> binary;
reverse_guard_test(is_constant, 1) -> constant;
reverse_guard_test(is_float, 1) -> float;
reverse_guard_test(is_function, 1) -> function;
reverse_guard_test(is_function, 2) -> function;
reverse_guard_test(is_integer, 1) -> integer;
reverse_guard_test(is_list, 1) -> list;
reverse_guard_test(is_number, 1) -> number;
reverse_guard_test(is_pid, 1) -> pid;
reverse_guard_test(is_port, 1) -> port;
reverse_guard_test(is_reference, 1) -> reference;
reverse_guard_test(is_tuple, 1) -> tuple;
reverse_guard_test(is_record, 2) -> record;
reverse_guard_test(is_record, 3) -> record;
reverse_guard_test(N, _A) -> N.
%% =====================================================================
%% Utility functions
is_remote_name({M,F,A}) when is_atom(M), is_atom(F), is_integer(A) -> true;
is_remote_name(_) -> false.
is_atom_pair({M,F}) when is_atom(M), is_atom(F) -> true;
is_atom_pair(_) -> false.
replace_last([_E], Xs) ->
Xs;
replace_last([E | Es], Xs) ->
[E | replace_last(Es, Xs)].
is_generator(E) ->
erl_syntax:type(E) =:= generator.
is_variable(E) ->
erl_syntax:type(E) =:= variable.
new_variables(N, St0) when N > 0 ->
{V, St1} = new_variable(St0),
{Vs, St2} = new_variables(N - 1, St1),
{[V | Vs], St2};
new_variables(0, St) ->
{[], St}.
new_variable(St0) ->
Fun = fun (N) ->
list_to_atom("V" ++ integer_to_list(N))
end,
Vs = St0#st.vars,
{Name, N} = new_name(St0#st.varc, Fun, Vs),
St1 = St0#st{varc = N + 1, vars = sets:add_element(Name, Vs)},
{erl_syntax:variable(Name), St1}.
new_fname({F, A}, St0) ->
Base = atom_to_list(F),
Fun = fun (N) ->
{list_to_atom(Base ++ "_" ++ integer_to_list(N)), A}
end,
Fs = St0#st.functions,
{{F1, _A} = Name, _N} = new_name(1, Fun, Fs),
{F1, St0#st{functions = sets:add_element(Name, Fs)}}.
new_name(N, F, Set) ->
Name = F(N),
case sets:is_element(Name, Set) of
true ->
new_name(N + 1, F, Set);
false ->
{Name, N}
end.
is_imported(F, Env) ->
dict:is_key(F, Env#env.imports).
is_auto_imported({erlang, N, A}) ->
is_auto_imported({N, A});
is_auto_imported({_, _N, _A}) ->
false;
is_auto_imported({N, A}) ->
erl_internal:bif(N, A).
is_nonlocal(N, Env) ->
case is_imported(N, Env) of
true ->
true;
false ->
is_auto_imported(N)
end.
get_var_exports(Node) ->
get_var_exports_1(erl_syntax:get_ann(Node)).
get_var_exports_1([{bound, B} | _Bs]) -> B;
get_var_exports_1([_ | Bs]) -> get_var_exports_1(Bs);
get_var_exports_1([]) -> [].
get_free_vars(Node) ->
get_free_vars_1(erl_syntax:get_ann(Node)).
get_free_vars_1([{free, B} | _Bs]) -> B;
get_free_vars_1([_ | Bs]) -> get_free_vars_1(Bs);
get_free_vars_1([]) -> [].
filename([C | T]) when is_integer(C), C > 0 ->
[C | filename(T)];
filename([H|T]) ->
filename(H) ++ filename(T);
filename([]) ->
[];
filename(N) when is_atom(N) ->
atom_to_list(N);
filename(N) ->
report_error("bad filename: `~P'.", [N, 25]),
exit(error).
get_env(Tree) ->
case lists:keyfind(env, 1, erl_syntax:get_ann(Tree)) of
{env, Env} ->
Env;
_ ->
[]
end.
rewrite(Source, Target) ->
erl_syntax:copy_attrs(Source, Target).
clone(Source, Target) ->
erl_syntax:copy_pos(Source, Target).
%% =====================================================================
%% Reporting
report_export_vars(F, L, Type, Opts) ->
report({F, L, "rewrote ~s-expression to export variables."},
[Type], Opts).
error_read_file(Name) ->
report_error("error reading file `~ts'.", [filename(Name)]).
error_write_file(Name) ->
report_error("error writing to file `~ts'.", [filename(Name)]).
error_backup_file(Name) ->
report_error("could not create backup of file `~ts'.",
[filename(Name)]).
error_open_output(Name) ->
report_error("cannot open file `~ts' for output.", [filename(Name)]).
verbosity(Opts) ->
case proplists:get_bool(quiet, Opts) of
true -> 0;
false ->
case proplists:get_value(verbose, Opts) of
true -> 2;
N when is_integer(N) -> N;
_ -> 1
end
end.
report_error(D) ->
report_error(D, []).
report_error({F, L, D}, Vs) ->
report({F, L, {error, D}}, Vs);
report_error(D, Vs) ->
report({error, D}, Vs).
%% warn(D, N) ->
%% warn(D, [], N).
warn({F, L, D}, Vs, N) ->
report({F, L, {warning, D}}, Vs, N);
warn(D, Vs, N) ->
report({warning, D}, Vs, N).
recommend(D, Vs, N) ->
report({recommend, D}, Vs, N).
verbose(D, Vs, N) ->
report(2, D, Vs, N).
report(D, Vs) ->
report(D, Vs, 1).
report(D, Vs, N) ->
report(1, D, Vs, N).
report(Level, _D, _Vs, N) when is_integer(N), N < Level ->
ok;
report(_Level, D, Vs, N) when is_integer(N) ->
io:put_chars(format(D, Vs));
report(Level, D, Vs, Options) when is_list(Options) ->
report(Level, D, Vs, verbosity(Options)).
format({error, D}, Vs) ->
["error: ", format(D, Vs)];
format({warning, D}, Vs) ->
["warning: ", format(D, Vs)];
format({recommend, D}, Vs) ->
["recommendation: ", format(D, Vs)];
format({"", L, D}, Vs) when is_integer(L), L > 0 ->
[io_lib:fwrite("~w: ", [L]), format(D, Vs)];
format({"", _L, D}, Vs) ->
format(D, Vs);
format({F, L, D}, Vs) when is_integer(L), L > 0 ->
[io_lib:fwrite("~ts:~w: ", [filename(F), L]), format(D, Vs)];
format({F, _L, D}, Vs) ->
[io_lib:fwrite("~ts: ", [filename(F)]), format(D, Vs)];
format(S, Vs) when is_list(S) ->
[io_lib:fwrite(S, Vs), $\n].
%% =====================================================================
