File 3381-Handle-macros-in-patterns.patch of Package erlang
From f098f67215a484a17837fede5b9c0c7a23c4c411 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?P=C3=A9ter=20G=C3=B6m=C3=B6ri?= <gomoripeti@gmail.com>
Date: Mon, 11 Jan 2021 02:40:15 +0100
Subject: [PATCH] Handle macros in patterns
The dodger used to replace a macro with a local function call. That works in
expressions but not in patterns like function heads or catch patterns. Instead
of a function call a tuple syntax is used which works in more places.
This change is motivated by the commonly used `?EXCEPTION` macro
```
try
...
catch
?EXCEPTION(Class, Reason, StackToken) ->
...
end.
```
Open source examples:
https://github.com/devinus/poolboy/commit/5d40cc517edc9bb8ee70756544167b63f66662f0
https://github.com/eproxus/meck/commit/558e925b48ce257b12e381080c851dc49c87d7bb
Fixes ERL-1429
---
lib/syntax_tools/src/epp_dodger.erl | 65 ++++++++++++-------
lib/syntax_tools/test/syntax_tools_SUITE.erl | 34 +++++++++-
.../epp_dodger_clever.erl | 12 ++++
.../syntax_tools_test.erl | 19 +++++-
4 files changed, 101 insertions(+), 29 deletions(-)
create mode 100644 lib/syntax_tools/test/syntax_tools_SUITE_data/epp_dodger_clever.erl
diff --git a/lib/syntax_tools/src/epp_dodger.erl b/lib/syntax_tools/src/epp_dodger.erl
index da22a91de0..8ee6368868 100644
--- a/lib/syntax_tools/src/epp_dodger.erl
+++ b/lib/syntax_tools/src/epp_dodger.erl
@@ -544,6 +544,7 @@ quickscan_macros([{'?',_}, {Type, _, _}=N | [{'(',_}|_]=Ts],
Ts1 = case skip_macro_args(Ts) of
{_, [{'->',_} | _] = Ts2} -> Ts2;
{_, [{'when',_} | _] = Ts2} -> Ts2;
+ {_, [{':',_} | _] = Ts2} -> Ts2;
_ -> Ts %% assume macro without arguments
end,
quickscan_macros_1(N, Ts1, As);
@@ -705,6 +706,8 @@ scan_macros([{'?', L}, {Type, _, _}=N | [{'(',_}|_]=Ts],
macro_call(Args, L, N, Rest, As, Opt);
[{'when',_} | _] ->
macro_call(Args, L, N, Rest, As, Opt);
+ [{':',_} | _] ->
+ macro_call(Args, L, N, Rest, As, Opt);
_ ->
macro(L, N, Ts, As, Opt)
end;
@@ -722,7 +725,7 @@ scan_macros([T | Ts], As, Opt) ->
scan_macros([], As, _Opt) ->
lists:reverse(As).
-%% Rewriting to a call which will be recognized by the post-parse pass
+%% Rewriting to a tuple which will be recognized by the post-parse pass
%% (we insert parentheses to preserve the precedences when parsing).
macro(L, {Type, _, A}, Rest, As, Opt) ->
@@ -731,17 +734,28 @@ macro(L, {Type, _, A}, Rest, As, Opt) ->
macro_call([{'(',_}, {')',_}], L, {_, Ln, _}=N, Rest, As, Opt) ->
{Open, Close} = parentheses(As),
scan_macros_1([], Rest,
- lists:reverse(Open ++ [{atom,L,?macro_call},
- {'(',L}, N, {')',Ln}] ++ Close,
- As), Opt);
+ %% {'?macro_call', N }
+ lists:reverse(Open ++ [{'{', L},
+ {atom, L, ?macro_call},
+ {',', L},
+ N,
+ {'}', Ln}] ++ Close,
+ As), Opt);
macro_call([{'(',_} | Args], L, {_, Ln, _}=N, Rest, As, Opt) ->
{Open, Close} = parentheses(As),
+ %% drop closing parenthesis
+ {')', _} = lists:last(Args), %% assert
+ Args1 = lists:droplast(Args),
%% note that we must scan the argument list; it may not be skipped
- scan_macros_1(Args ++ Close,
- Rest,
- lists:reverse(Open ++ [{atom,L,?macro_call},
- {'(',L}, N, {',',Ln}],
- As), Opt).
+ scan_macros_1(Args1 ++ [{'}', Ln} | Close],
+ Rest,
+ %% {'?macro_call', N, Arg1, ... }
+ lists:reverse(Open ++ [{'{', L},
+ {atom, L, ?macro_call},
+ {',', L},
+ N,
+ {',', Ln}],
+ As), Opt).
macro_atom(atom, A) ->
list_to_atom(?atom_prefix ++ atom_to_list(A));
@@ -798,21 +812,24 @@ rewrite(Node) ->
_ ->
Node
end;
- application ->
- F = erl_syntax:application_operator(Node),
- case erl_syntax:type(F) of
- atom ->
- case erl_syntax:atom_value(F) of
- ?macro_call ->
- [A | As] = erl_syntax:application_arguments(Node),
- M = erl_syntax:macro(A, rewrite_list(As)),
- erl_syntax:copy_pos(Node, M);
- _ ->
- rewrite_1(Node)
- end;
- _ ->
- rewrite_1(Node)
- end;
+ tuple ->
+ case erl_syntax:tuple_elements(Node) of
+ [MagicWord, A | As] ->
+ case erl_syntax:type(MagicWord) of
+ atom ->
+ case erl_syntax:atom_value(MagicWord) of
+ ?macro_call ->
+ M = erl_syntax:macro(A, rewrite_list(As)),
+ erl_syntax:copy_pos(Node, M);
+ _ ->
+ rewrite_1(Node)
+ end;
+ _ ->
+ rewrite_1(Node)
+ end;
+ _ ->
+ rewrite_1(Node)
+ end;
_ ->
rewrite_1(Node)
end.
diff --git a/lib/syntax_tools/test/syntax_tools_SUITE.erl b/lib/syntax_tools/test/syntax_tools_SUITE.erl
index 9baf36ce11..14a7912642 100644
--- a/lib/syntax_tools/test/syntax_tools_SUITE.erl
+++ b/lib/syntax_tools/test/syntax_tools_SUITE.erl
@@ -25,7 +25,8 @@
%% Test cases
-export([app_test/1,appup_test/1,smoke_test/1,revert/1,revert_map/1,
revert_map_type/1,wrapped_subtrees/1,
- t_abstract_type/1,t_erl_parse_type/1,t_type/1, t_epp_dodger/1,
+ t_abstract_type/1,t_erl_parse_type/1,t_type/1,
+ t_epp_dodger/1,t_epp_dodger_clever/1,
t_comment_scan/1,t_igor/1,t_erl_tidy/1,t_prettypr/1]).
suite() -> [{ct_hooks,[ts_install_cth]}].
@@ -33,7 +34,8 @@ suite() -> [{ct_hooks,[ts_install_cth]}].
all() ->
[app_test,appup_test,smoke_test,revert,revert_map,revert_map_type,
wrapped_subtrees,
- t_abstract_type,t_erl_parse_type,t_type,t_epp_dodger,
+ t_abstract_type,t_erl_parse_type,t_type,
+ t_epp_dodger,t_epp_dodger_clever,
t_comment_scan,t_igor,t_erl_tidy,t_prettypr].
groups() ->
@@ -330,6 +332,13 @@ t_epp_dodger(Config) when is_list(Config) ->
ok = test_epp_dodger(Filenames,DataDir,PrivDir),
ok.
+t_epp_dodger_clever(Config) when is_list(Config) ->
+ DataDir = ?config(data_dir, Config),
+ PrivDir = ?config(priv_dir, Config),
+ Filenames = ["epp_dodger_clever.erl"],
+ ok = test_epp_dodger_clever(Filenames,DataDir,PrivDir),
+ ok.
+
t_comment_scan(Config) when is_list(Config) ->
DataDir = ?config(data_dir, Config),
Filenames = test_files(),
@@ -447,9 +456,30 @@ test_epp_dodger([Filename|Files],DataDir,PrivDir) ->
ok = pretty_print_parse_forms(FsForms,PrivDir,Filename),
test_epp_dodger(Files,DataDir,PrivDir).
+test_epp_dodger_clever([], _, _) -> ok;
+test_epp_dodger_clever([Filename|Files],DataDir,PrivDir) ->
+ io:format("Parsing ~p~n", [Filename]),
+ InFile = filename:join(DataDir, Filename),
+ Parsers = [{fun(File) ->
+ epp_dodger:parse_file(File, [clever])
+ end, parse_file},
+ {fun(File) ->
+ epp_dodger:quick_parse_file(File, [clever])
+ end, quick_parse_file}],
+ FsForms = parse_with(Parsers, InFile),
+ ok = pretty_print_parse_forms(FsForms,PrivDir,Filename),
+ test_epp_dodger_clever(Files,DataDir,PrivDir).
+
parse_with([],_) -> [];
parse_with([{Fun,ParserType}|Funs],File) ->
{ok, Fs} = Fun(File),
+ ErrorMarkers = [begin
+ print_error_markers(F, File),
+ F
+ end
+ || F <- Fs,
+ erl_syntax:type(F) =:= error_marker],
+ [] = ErrorMarkers,
[{Fs,ParserType}|parse_with(Funs,File)].
pretty_print_parse_forms([],_,_) -> ok;
diff --git a/lib/syntax_tools/test/syntax_tools_SUITE_data/epp_dodger_clever.erl b/lib/syntax_tools/test/syntax_tools_SUITE_data/epp_dodger_clever.erl
new file mode 100644
index 0000000000..4a3be06d98
--- /dev/null
+++ b/lib/syntax_tools/test/syntax_tools_SUITE_data/epp_dodger_clever.erl
@@ -0,0 +1,12 @@
+-module(epp_dodger_clever).
+
+-export([foo1/0]).
+
+-define(macro_string, "hello world").
+
+foo1() ->
+ % string combining ?
+ [?macro_string
+ "hello world ",
+ "more hello"
+ ?macro_string].
diff --git a/lib/syntax_tools/test/syntax_tools_SUITE_data/syntax_tools_test.erl b/lib/syntax_tools/test/syntax_tools_SUITE_data/syntax_tools_test.erl
index dd3f88d7a8..b8a21ef0ab 100644
--- a/lib/syntax_tools/test/syntax_tools_SUITE_data/syntax_tools_test.erl
+++ b/lib/syntax_tools/test/syntax_tools_SUITE_data/syntax_tools_test.erl
@@ -6,7 +6,7 @@
-module(syntax_tools_test).
--export([foo1/0,foo2/2,foo3/0,foo4/3,foo5/1]).
+-export([foo1/0,foo2/2,foo3/0,foo4/3,foo5/1,foo6/2]).
-include_lib("kernel/include/file.hrl").
-record(state, { a, b, c, d}).
@@ -24,6 +24,7 @@
-define(macro_string, "hello world").
-define(macro_argument1(X), (X + 3)).
-define(macro_argument2(X,Y), (X + 3 * Y)).
+-define(macro_argument3(X), {error, X}).
-define(macro_block(X), begin X end).
-define(macro_if(X1,X2), if X1 -> X2; true -> none end).
@@ -48,8 +49,7 @@ foo1() ->
%% macro test
foo2(A,B) ->
% string combining ?
- [?macro_string, ?macro_string
- ?macro_string,
+ [?macro_string, ?macro_string ++
"hello world "
"more hello",
[?macro_simple1,
@@ -113,3 +113,16 @@ foo5(A) ->
error:?macro_simple5 ->
nope
end.
+
+%% macros in patterns
+foo6(?MACRO_SIMPLE2, ?macro_argument3(A)) ->
+ try foo2(A,A) of
+ R -> R
+ catch
+ ?macro_argument3(B) ->
+ B;
+ error:?macro_argument3(B) ->
+ B;
+ error:?macro_argument3(B):_ ->
+ B
+ end.
--
2.26.2
