Fix issue with integer overflow check

Fixes #6025

Author: cristianoc

CHANGELOG.md

@@ -72,6 +72,7 @@ These are only breaking changes for unformatted code.
 - Fix location issue for the treatment of `async` functions where hovering on the body with a type error would show `'a => promise<'a>` everywhere https://github.com/rescript-lang/rescript-compiler/pull/6012
 - Fix formatting of `switch` expressions that contain brace `cases` inside https://github.com/rescript-lang/rescript-compiler/pull/6015
 - Support `@gentype.import` as an alias to `@genType.import` in the compiler https://github.com/rescript-lang/rescript-compiler/pull/6020
+- Fix issue with integer overflow check
 
 #### :nail_care: Polish
 

jscomp/build_tests/super_errors/expected/intoverflow.res.expected

@@ -0,0 +1,33 @@
+
+  Warning number 107
+  /.../fixtures/intoverflow.res:2:15-27
+
+  1 │ let v1: int = 2_147_483_647
+  2 │ let v2: int = 2_147_483_648
+  3 │ let v3: int = 2_147_483_649
+  4 │ let v4: int = -2_147_483_647
+
+  Integer literal exceeds the range of representable integers of type int
+
+
+  Warning number 107
+  /.../fixtures/intoverflow.res:3:15-27
+
+  1 │ let v1: int = 2_147_483_647
+  2 │ let v2: int = 2_147_483_648
+  3 │ let v3: int = 2_147_483_649
+  4 │ let v4: int = -2_147_483_647
+  5 │ let v5: int = -2_147_483_648
+
+  Integer literal exceeds the range of representable integers of type int
+
+
+  Warning number 107
+  /.../fixtures/intoverflow.res:6:16-28
+
+  4 │ let v4: int = -2_147_483_647
+  5 │ let v5: int = -2_147_483_648
+  6 │ let v6: int = -2_147_483_649
+  7 │ 
+
+  Integer literal exceeds the range of representable integers of type int

jscomp/build_tests/super_errors/fixtures/intoverflow.res

@@ -0,0 +1,6 @@
+let v1: int = 2_147_483_647
+let v2: int = 2_147_483_648
+let v3: int = 2_147_483_649
+let v4: int = -2_147_483_647
+let v5: int = -2_147_483_648
+let v6: int = -2_147_483_649

jscomp/frontend/bs_ast_invariant.ml

@@ -89,9 +89,7 @@ let check_constant loc kind (const : Parsetree.constant) =
          affect int ranges
       *)
       try
-        ignore
-          (if String.length s = 0 || s.[0] = '-' then Int32.of_string s
-          else Int32.of_string ("-" ^ s))
+        ignore @@ Int32.of_string s
       with _ -> Bs_warnings.warn_literal_overflow loc)
   | Pconst_integer (_, Some 'n') ->
       Location.raise_errorf ~loc "literal with `n` suffix is not supported"