fix: correct floating point literal parsing

Author: amaanq

grammar.js

@@ -141,7 +141,7 @@ module.exports = grammar({
     decimal_floating_point_literal: _ => token(choice(
       seq(DECIMAL_DIGITS, '.', optional(DECIMAL_DIGITS), optional(seq((/[eE]/), optional(choice('-', '+')), DECIMAL_DIGITS)), optional(/[fFdD]/)),
       seq('.', DECIMAL_DIGITS, optional(seq((/[eE]/), optional(choice('-', '+')), DECIMAL_DIGITS)), optional(/[fFdD]/)),
-      seq(DIGITS, /[eEpP]/, optional(choice('-', '+')), DECIMAL_DIGITS, optional(/[fFdD]/)),
+      seq(DIGITS, /[eE]/, optional(choice('-', '+')), DECIMAL_DIGITS, optional(/[fFdD]/)),
       seq(DIGITS, optional(seq((/[eE]/), optional(choice('-', '+')), DECIMAL_DIGITS)), (/[fFdD]/)),
     )),
 
@@ -152,7 +152,7 @@ module.exports = grammar({
         seq(optional(HEX_DIGITS), '.', HEX_DIGITS),
       ),
       optional(seq(
-        /[eEpP]/,
+        /[pP]/,
         optional(choice('-', '+')),
         DIGITS,
         optional(/[fFdD]/),

test/corpus/literals.txt

@@ -20,13 +20,15 @@ hex integer literals
 0xa_bcd_ef0;
 0Xa_bcd_ef0;
 0X8000L;
+0x7e-0x21;
 
 ---
 
 (program
   (expression_statement (hex_integer_literal))
   (expression_statement (hex_integer_literal))
-  (expression_statement (hex_integer_literal)))
+  (expression_statement (hex_integer_literal))
+  (expression_statement (binary_expression (hex_integer_literal) (hex_integer_literal))))
 
 ======================
 octal integer literals
@@ -77,7 +79,7 @@ floating point literals
 0.0e-4;
 .2e-2;
 0x5.4;
-0x5.4e-10;
+0x5.4p-10;
 
 ---