OTP-8657 New Erlang scanner tokens: '..' and '...'

The Erlang scanner has been augmented with two new tokens: .. and ....

3 files changed, 18 insertions, 9 deletions

diff --git a/lib/stdlib/src/erl_parse.yrl b/lib/stdlib/src/erl_parse.yrl
index 5287f55e59..141ee18afd 100644
--- a/lib/stdlib/src/erl_parse.yrl
+++ b/lib/stdlib/src/erl_parse.yrl
@@ -61,7 +61,7 @@ char integer float atom string var
 '++' '--'
 '==' '/=' '=<' '<' '>=' '>' '=:=' '=/=' '<='
 '<<' '>>'
-'!' '=' '::'
+'!' '=' '::' '..' '...'
 'spec' % helper
 dot.
 
@@ -135,7 +135,7 @@ type -> atom ':' atom '(' top_types ')'   : {remote_type, ?line('$1'),
                                              ['$1', '$3', '$5']}.
 type -> '[' ']'                           : {type, ?line('$1'), nil, []}.
 type -> '[' top_type ']'                  : {type, ?line('$1'), list, ['$2']}.
-type -> '[' top_type ',' '.' '.' '.' ']'  : {type, ?line('$1'),
+type -> '[' top_type ',' '...' ']'        : {type, ?line('$1'),
                                              nonempty_list, ['$2']}.
 type -> '{' '}'                           : {type, ?line('$1'), tuple, []}.
 type -> '{' top_types '}'                 : {type, ?line('$1'), tuple, '$2'}.
@@ -144,8 +144,8 @@ type -> '#' atom '{' field_types '}'      : {type, ?line('$1'),
                                              record, ['$2'|'$4']}.
 type -> binary_type                       : '$1'.
 type -> int_type                          : '$1'.
-type -> int_type '.' '.' int_type         : {type, ?line('$1'), range,
-                                             ['$1', '$4']}.
+type -> int_type '..' int_type            : {type, ?line('$1'), range,
+                                             ['$1', '$3']}.
 type -> 'fun' '(' ')'                     : {type, ?line('$1'), 'fun', []}.
 type -> 'fun' '(' fun_type_100 ')'        : '$3'.
 
@@ -153,9 +153,9 @@ int_type -> integer                       : '$1'.
 int_type -> '-' integer                   : abstract(-normalise('$2'),
                                                      ?line('$2')).
 
-fun_type_100 -> '(' '.' '.' '.' ')' '->' top_type
+fun_type_100 -> '(' '...' ')' '->' top_type
                                           : {type, ?line('$1'), 'fun',
-                                             [{type, ?line('$1'), any}, '$7']}.
+                                             [{type, ?line('$1'), any}, '$5']}.
 fun_type_100 -> fun_type                  : '$1'.
 
 fun_type -> '(' ')' '->' top_type  : {type, ?line('$1'), 'fun',
diff --git a/lib/stdlib/src/erl_scan.erl b/lib/stdlib/src/erl_scan.erl
index 1013d54bdc..c179c3d067 100644
--- a/lib/stdlib/src/erl_scan.erl
+++ b/lib/stdlib/src/erl_scan.erl
@@ -442,6 +442,14 @@ scan1([$\%=C|Cs], St, Line, Col, Toks) ->
     scan_comment(Cs, St, Line, Col, Toks, [C]);
 scan1([C|Cs], St, Line, Col, Toks) when ?DIGIT(C) ->
     scan_number(Cs, St, Line, Col, Toks, [C]);
+scan1("..."++Cs, St, Line, Col, Toks) ->
+    tok2(Cs, St, Line, Col, Toks, "...", '...', 3);
+scan1(".."=Cs, _St, Line, Col, Toks) ->
+    {more,{Cs,Col,Toks,Line,[],fun scan/6}};
+scan1(".."++Cs, St, Line, Col, Toks) ->
+    tok2(Cs, St, Line, Col, Toks, "..", '..', 2);
+scan1("."=Cs, _St, Line, Col, Toks) ->
+    {more,{Cs,Col,Toks,Line,[],fun scan/6}};
 scan1([$.=C|Cs], St, Line, Col, Toks) ->
     scan_dot(Cs, St, Line, Col, Toks, [C]);
 scan1([$"|Cs], St, Line, Col, Toks) -> %" Emacs
@@ -644,8 +652,6 @@ scan_dot([$\n=C|Cs], St, Line, Col, Toks, Ncs) ->
 scan_dot([C|Cs], St, Line, Col, Toks, Ncs) when ?WHITE_SPACE(C) ->
     Attrs = attributes(Line, Col, St, Ncs++[C]),
     {ok,[{dot,Attrs}|Toks],Cs,Line,incr_column(Col, 2)};
-scan_dot([]=Cs, _St, Line, Col, Toks, Ncs) ->
-    {more,{Cs,Col,Toks,Line,Ncs,fun scan_dot/6}};
 scan_dot(eof=Cs, St, Line, Col, Toks, Ncs) ->
     Attrs = attributes(Line, Col, St, Ncs),
     {ok,[{dot,Attrs}|Toks],Cs,Line,incr_column(Col, 1)};
diff --git a/lib/stdlib/test/erl_scan_SUITE.erl b/lib/stdlib/test/erl_scan_SUITE.erl
index afeb67eeb1..32eb97bc92 100644
--- a/lib/stdlib/test/erl_scan_SUITE.erl
+++ b/lib/stdlib/test/erl_scan_SUITE.erl
@@ -185,7 +185,7 @@ reserved_words() ->
          'andalso', 'orelse', 'end', 'fun', 'if', 'let', 'of',
          'query', 'receive', 'when', 'bnot', 'not', 'div',
          'rem', 'band', 'and', 'bor', 'bxor', 'bsl', 'bsr',
-         'or', 'xor'] ,
+         'or', 'xor'],
     [begin
          ?line {RW, true} = {RW, erl_scan:reserved_word(RW)},
          S = atom_to_list(RW),
@@ -244,6 +244,9 @@ punctuations() ->
             {'\\',1},{'^',1},{'`',1},{'~',1}],
     ?line test_string("#&*+/:<>?@\\^`~", PTs2),
 
+    ?line test_string(".. ", [{'..',1}]),
+    ?line test("1 .. 2"),
+    ?line test_string("...", [{'...',1}]),
     ok.
 
 comments() ->