Make sure the Erlang shell prompt can handle Unicode

4 files changed, 28 insertions, 20 deletions

diff --git a/lib/kernel/src/group.erl b/lib/kernel/src/group.erl
index f92c6f7208..4d2e31a429 100644
--- a/lib/kernel/src/group.erl
+++ b/lib/kernel/src/group.erl
@@ -424,7 +424,7 @@ get_password_chars(Drv,Buf) ->
     end.
 
 get_chars(Prompt, M, F, Xa, Drv, Buf, Encoding) ->
-    Pbs = prompt_bytes(Prompt),
+    Pbs = prompt_bytes(Prompt, Encoding),
     get_chars_loop(Pbs, M, F, Xa, Drv, Buf, start, Encoding).
 
 get_chars_loop(Pbs, M, F, Xa, Drv, Buf0, State, Encoding) ->
@@ -688,9 +688,9 @@ edit_password([Char|Cs],Chars) ->
     edit_password(Cs,[Char|Chars]).
 
 %% prompt_bytes(Prompt)
-%%  Return a flat list of bytes for the Prompt.
-prompt_bytes(Prompt) ->
-    lists:flatten(io_lib:format_prompt(Prompt)).
+%%  Return a flat list of characters for the Prompt.
+prompt_bytes(Prompt, Encoding) ->
+    lists:flatten(io_lib:format_prompt(Prompt, Encoding)).
 
 cast(L, binary,latin1) when is_list(L) ->
     list_to_binary(L);
diff --git a/lib/kernel/src/user.erl b/lib/kernel/src/user.erl
index 629b7ae67f..d6449d9e5e 100644
--- a/lib/kernel/src/user.erl
+++ b/lib/kernel/src/user.erl
@@ -673,8 +673,9 @@ get_chars_more(State, M, F, Xa, Port, Q, Enc) ->
 prompt(_Port, '') -> ok;
 
 prompt(Port, Prompt) ->
-    put_port(wrap_characters_to_binary(io_lib:format_prompt(Prompt),
-                                       unicode, get(encoding)),
+    Encoding = get(encoding),
+    put_port(wrap_characters_to_binary(io_lib:format_prompt(Prompt, Encoding),
+                                       unicode, Encoding),
              Port).
 
 %% Convert error code to make it look as before
diff --git a/lib/stdlib/src/io.erl b/lib/stdlib/src/io.erl
index bc1727c027..ecf2aeb375 100644
--- a/lib/stdlib/src/io.erl
+++ b/lib/stdlib/src/io.erl
@@ -73,9 +73,9 @@ o_request(Io, Request, Func) ->
 put_chars(Chars) ->
     put_chars(default_output(), Chars).
 
--spec put_chars(IoDevice, IoData) -> 'ok' when
+-spec put_chars(IoDevice, CharData) -> 'ok' when
       IoDevice :: device(),
-      IoData :: unicode:chardata().
+      CharData :: unicode:chardata().
 
 put_chars(Io, Chars) ->
     o_request(Io, {put_chars,unicode,Chars}, put_chars).
diff --git a/lib/stdlib/src/io_lib.erl b/lib/stdlib/src/io_lib.erl
index 461da422ef..44c1d2132a 100644
--- a/lib/stdlib/src/io_lib.erl
+++ b/lib/stdlib/src/io_lib.erl
@@ -62,7 +62,7 @@
 -export([fwrite/2,fread/2,fread/3,format/2]).
 -export([print/1,print/4,indentation/2]).
 
--export([write/1,write/2,write/3,nl/0,format_prompt/1]).
+-export([write/1,write/2,write/3,nl/0,format_prompt/1,format_prompt/2]).
 -export([write_atom/1,write_string/1,write_string/2,write_unicode_string/1,
          write_unicode_string/2, write_char/1, write_unicode_char/1]).
 
@@ -178,27 +178,34 @@ indentation(Chars, Current) ->
 
 
 %% Format an IO-request prompt (handles formatting errors safely).
-%% Atoms, binaries, and iolists can be used as-is, and will be
-%% printed without any additional quotes.
-%% Note that the output is a deep string, and not an iolist (i.e.,
-%% it may be deep, but never contains binaries, due to the "~s").
+%% Atoms, binaries, and iolists (or unicode:charlist()) can be used
+%% as-is, and will be printed without any additional quotes.
 
 -spec format_prompt(term()) -> chars().
 
-format_prompt({format,Format,Args}) ->
-    format_prompt(Format,Args);
-format_prompt(Prompt)
-  when is_list(Prompt); is_atom(Prompt); is_binary(Prompt) ->
-    format_prompt("~ts", [Prompt]);
 format_prompt(Prompt) ->
-    format_prompt("~tp", [Prompt]).
+    format_prompt(Prompt, latin1).
+
+-spec format_prompt(term(), atom()) -> chars().
+
+format_prompt({format,Format,Args}, _Encoding) ->
+    do_format_prompt(Format, Args);
+format_prompt(Prompt, Encoding)
+  when is_list(Prompt); is_atom(Prompt); is_binary(Prompt) ->
+    do_format_prompt(add_modifier(Encoding, "s"), [Prompt]);
+format_prompt(Prompt, Encoding) ->
+    do_format_prompt(add_modifier(Encoding, "p"), [Prompt]).
 
-format_prompt(Format, Args) ->
+do_format_prompt(Format, Args) ->
     case catch io_lib:format(Format, Args) of
 	{'EXIT',_} -> "???";
 	List -> List
     end.
 
+add_modifier(latin1, C) ->
+    "~"++C;
+add_modifier(_, C) ->
+    "~t"++C.
 
 %% write(Term)
 %% write(Term, Depth)