From d03da2e9d2a61ae47c9785d7c804e9863cd29321 Mon Sep 17 00:00:00 2001
From: trdthg <trdthg47@gmail.com>
Date: Wed, 10 Jul 2024 06:21:21 +0000
Subject: [PATCH] Fix lexer rule to handle operator of format like `operator +
 comment`

---
 src/lib/lexer.mll                   | 23 +++++++++++++-----
 test/format/default/operator.expect | 36 +++++++++++++++++++++++++++++
 test/format/operator.sail           | 28 ++++++++++++++++++++++
 3 files changed, 81 insertions(+), 6 deletions(-)
 create mode 100644 test/format/default/operator.expect
 create mode 100644 test/format/operator.sail

diff --git a/src/lib/lexer.mll b/src/lib/lexer.mll
index 954abb364..d889d9a91 100644
--- a/src/lib/lexer.mll
+++ b/src/lib/lexer.mll
@@ -172,10 +172,12 @@ let tyvar_start = '\''
 let oper_char = ['!''%''&''*''+''-''.''/'':''<''=''>''@''^''|']
 let oper_char_no_slash = ['!''%''&''*''+''-''.'':''<''=''>''@''^''|']
 let oper_char_no_slash_star = ['!''%''&''+''-''.'':''<''=''>''@''^''|']
-let operator1 = oper_char
-let operator2 = oper_char oper_char_no_slash_star | oper_char_no_slash oper_char
-let operatorn = oper_char oper_char_no_slash_star (oper_char* ('_' ident)?) | oper_char_no_slash oper_char (oper_char* ('_' ident)?) | oper_char ('_' ident)?
-let operator = operator1 | operator2 | operatorn
+let oper_char_no_star = ['!''%''&''+''-''.''/'':''<''=''>''@''^''|']
+let operator_any_start = oper_char (oper_char_no_slash_star oper_char)*
+                        | (oper_char oper_char_no_slash_star)*
+let operator_no_slash_start = oper_char_no_slash (oper_char oper_char_no_slash_star)*
+                            | (oper_char_no_slash_star oper_char)*
+let operator = (operator_any_start | operator_no_slash_start) ('_' ident)?
 let escape_sequence = ('\\' ['\\''\"''\'''n''t''b''r']) | ('\\' digit digit digit) | ('\\' 'x' hexdigit hexdigit)
 let lchar = [^'\n']
 
@@ -188,7 +190,7 @@ rule token comments = parse
       token comments lexbuf }
   | "@"                                 { At }
   | "2" ws "^"                          { TwoCaret }
-  | "^"					{ Caret }
+  | "^"					                        { Caret }
   | "::"                                { ColonColon }
   | ":"                                 { Colon ":" }
   | ","                                 { Comma }
@@ -235,7 +237,16 @@ rule token comments = parse
     { Fixity (InfixL, Big_int.of_string (Char.escaped p), op) }
   | "infixr" ws (digit as p) ws (operator as op)
     { Fixity (InfixR, Big_int.of_string (Char.escaped p), op) }
-  | operator as op                        { OpId op }
+  | operator as op                        { 
+      OpId op }
+  | (operator as op) ['/'] ['*'] {
+      block_comment comments (Lexing.lexeme_start_p lexbuf) (Buffer.create 10) 0 lexbuf;
+      if op = "=" then Eq "=" else OpId op
+    }
+  | (operator as op) ['/'] ['/'] {
+      line_comment comments (Lexing.lexeme_start_p lexbuf) (Buffer.create 10) lexbuf;
+      if op = "=" then Eq "=" else OpId op
+    }
   | tyvar_start startident ident* as i    { TyVar i }
   | "~"                                   { Id "~" }
   | startident ident* as i                { if M.mem i kw_table then
diff --git a/test/format/default/operator.expect b/test/format/default/operator.expect
new file mode 100644
index 000000000..37d688bbc
--- /dev/null
+++ b/test/format/default/operator.expect
@@ -0,0 +1,36 @@
+default Order dec
+$include <prelude.sail>
+
+infix 4 ===_u
+infix 4 =/
+infix 4 ===/_u
+infix 4 /=/=/=_u
+infix 4 ===*_u
+
+val operator ===/_u : forall 'n. (int('n), int('n)) -> bool
+function operator ===/_u(x, y) = x == y
+
+val operator =/ : forall 'n. (int('n), int('n)) -> bool
+function operator =/(x, y) = x == y
+
+function f () = {
+    if eq2_comment == /**/ /**/ 1 then {
+        1
+    };
+
+    if eq_slash =/ 1 then {
+        1
+    };
+
+    let eq_comment =
+        /**/ 1;
+    let eq_comment =
+        //
+        1;
+
+    if eq3_slash ===/_u 1 then {
+        1
+    };
+
+    0
+}
diff --git a/test/format/operator.sail b/test/format/operator.sail
new file mode 100644
index 000000000..054646911
--- /dev/null
+++ b/test/format/operator.sail
@@ -0,0 +1,28 @@
+default Order dec
+$include <prelude.sail>
+
+infix 4 ===_u
+infix 4 =/
+infix 4 ===/_u
+infix 4 /=/=/=_u
+infix 4 ===*_u
+
+val operator ===/_u : forall 'n. (int('n), int('n)) -> bool
+function operator ===/_u(x, y) = x == y
+
+val operator =/ : forall 'n. (int('n), int('n)) -> bool
+function operator =/(x, y) = x == y
+
+function f () = {
+    if eq2_comment /**/==/**/ 1 then { 1 };
+    
+    if eq_slash =/ 1 then { 1 };
+
+    let eq_comment =/**/ 1;
+    let eq_comment =//
+    1;
+
+    if eq3_slash ===/_u 1 then { 1 };
+    
+    0
+}