Simplified improvement for absint() that always returns an int

src/wp-includes/load.php

@@ -1461,12 +1461,34 @@ function is_multisite() {
  * Converts a value to non-negative integer.
  *
  * @since 2.5.0
+ * @since 7.2.0 The `int` return type was added. Values beyond the integer
+ *              range are now capped at `PHP_INT_MAX` rather than overflowing.
  *
  * @param mixed $maybeint Data you wish to have converted to a non-negative integer.
  * @return int A non-negative integer.
+ * @phpstan-return non-negative-int
  */
-function absint( $maybeint ) {
-	return abs( (int) $maybeint );
+function absint( $maybeint ): int {
+	if ( is_float( $maybeint ) ) {
+		if ( ! is_finite( $maybeint ) ) {
+			// Casting `NAN` or `INF` to int has produced `0` since PHP 7.0.
+			return 0;
+		}
+
+		if ( $maybeint <= (float) PHP_INT_MIN || $maybeint >= (float) PHP_INT_MAX ) {
+			// Casting a float beyond the integer range is unreliable and warns as of PHP 8.5.
+			return PHP_INT_MAX;
+		}
+	}
+
+	$maybeint = (int) $maybeint;
+
+	if ( PHP_INT_MIN === $maybeint ) {
+		// `abs( PHP_INT_MIN )` overflows to a float, as `PHP_INT_MAX` is one less than `-PHP_INT_MIN`.
+		return PHP_INT_MAX;
+	}
+
+	return abs( $maybeint );
 }
 
 /**

tests/phpunit/data/functions/absint-enums.php

@@ -0,0 +1,17 @@
+<?php
+/**
+ * Enum fixtures for the absint() tests.
+ *
+ * Enum syntax requires PHP 8.1, so these are kept out of the test class file,
+ * which must remain parseable on the minimum supported PHP version.
+ *
+ * @see Tests_Functions_Absint
+ */
+
+enum Absint_Test_Pure_Enum {
+	case Hearts;
+}
+
+enum Absint_Test_Backed_Enum: int {
+	case Ace = 1;
+}