internal/intconv: Split

1 files changed, 15 insertions, 0 deletions

diff --git a/internal/intconv/u64_i64.go b/internal/intconv/u64_i64.go
new file mode 100644
index 00000000..59b26a73
--- /dev/null
+++ b/internal/intconv/u64_i64.go
@@ -0,0 +1,15 @@
+package intconv
+
+import (
+	"fmt"
+	"math"
+)
+
+// Uint64ToInt64 converts v to int64, returning an error if it overflows.
+func Uint64ToInt64(v uint64) (int64, error) {
+	if v > math.MaxInt64 {
+		return 0, fmt.Errorf("intconv: uint64 %d overflows int64", v)
+	}
+
+	return int64(v), nil
+}