From 3af842f0e89125e65a87e5752234bf7e0051aa12 Mon Sep 17 00:00:00 2001
From: Mason Remaley <mason@anthropicstudios.com>
Date: Mon, 8 Dec 2025 17:24:17 -0800
Subject: [PATCH] Fixes enums.fromInt failing at compile time on in range but
 invalid values

---
 lib/std/enums.zig | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/std/enums.zig b/lib/std/enums.zig
index 0815a50f38c5f89ac69efe904e471928c13b35f8..76deff5421ad8272804a9fba751442c4a4bc83bc 100644
--- a/lib/std/enums.zig
+++ b/lib/std/enums.zig
@@ -22,7 +22,7 @@ pub fn fromInt(comptime E: type, integer: anytype) ?E {
     // without requiring an inline loop.
     // This generates better machine code.
     for (values(E)) |value| {
-        if (@intFromEnum(value) == integer) return @enumFromInt(integer);
+        if (@intFromEnum(value) == integer) return value;
     }
     return null;
 }
@@ -213,6 +213,7 @@ test fromInt {
         B,
     };
     const E3 = enum(i8) { A, _ };
+    const E4 = enum(u8) { A };
 
     var zero: u8 = 0;
     var one: u16 = 1;
@@ -226,6 +227,10 @@ test fromInt {
     try testing.expectEqual(null, fromInt(E1, one));
     try testing.expectEqual(null, fromInt(E3, 128));
     try testing.expectEqual(null, fromInt(E3, -129));
+
+    // `fromInt` used to produce a compiler error instead of `null` if trying to convert an integer
+    // that wasn't out of range, but also wasn't a valid value.
+    try testing.expectEqual(null, fromInt(E4, 1));
 }
 
 /// A set of enum elements, backed by a bitfield.  If the enum
-- 
2.54.0