fix: add test for checkNumeric

Author: robbielyman

src/lib.zig

@@ -3363,21 +3363,22 @@ pub const Lua = opaque {
     /// * Pushes: `0`
     /// * Errors: `explained in text / on purpose`
     pub fn checkNumeric(lua: *Lua, comptime T: type, arg: i32) T {
-        if (@typeInfo(T) == .int) return std.math.cast(T, lua.checkNumber(arg)) orelse {
+        if (comptime @typeInfo(T) != .int) return @floatCast(lua.checkNumber(arg));
+        return std.math.cast(T, lua.checkInteger(arg)) orelse {
             const error_msg = comptime msg: {
                 var buf: [1024]u8 = undefined;
                 const info = @typeInfo(T).int;
                 const signedness = switch (info.signedness) {
                     .unsigned => "u",
                     .signed => "i",
                 };
-                break :msg std.fmt.bufPrintZ(&buf, "Integer argument doesn't fit inside {s}{d} range [{d}, {d}]", .{
+                const output = std.fmt.bufPrintZ(&buf, "integer argument doesn't fit inside {s}{d} range [{d}, {d}]", .{
                     signedness, info.bits, std.math.minInt(T), std.math.maxInt(T),
                 }) catch unreachable;
+                break :msg output[0..output.len :0].*;
             };
-            lua.argError(arg, error_msg);
+            lua.argError(arg, &error_msg);
         };
-        return @floatCast(lua.checkNumber(arg));
     }
 
     /// Checks whether the function argument `arg` is a number and returns this number cast to an i32

src/tests.zig

@@ -3056,12 +3056,38 @@ test "error union for CFn" {
     };
 }
 
-test "pushNumeric and toNumeric" {
+test "checkNumeric and toNumeric" {
+    const error_msg = "bad argument #1 to '?' (integer argument doesn't fit inside u8 range [0, 255])";
+
     const lua: *Lua = try .init(testing.allocator);
     defer lua.deinit();
 
-    const num: u32 = 100;
-    lua.pushInteger(num);
-    const pull = lua.toNumeric(u32, lua.getTop());
-    try std.testing.expectEqual(num, pull);
+    lua.pushFunction(zlua.wrap(struct {
+        fn f(l: *Lua) i32 {
+            _ = l.checkNumeric(u8, 1);
+            return 1;
+        }
+    }.f));
+    const idx = lua.getTop();
+
+    lua.pushValue(idx);
+    lua.pushInteger(128);
+    try lua.protectedCall(.{
+        .args = 1,
+        .results = 1,
+    });
+    const val = lua.toNumeric(u8, lua.getTop());
+    try std.testing.expectEqual(128, val);
+
+    lua.pushValue(idx);
+    lua.pushInteger(256);
+    if (lua.protectedCall(.{
+        .args = 1,
+        .results = 0,
+    })) |_| {
+        return error.ExpectedError;
+    } else |_| {
+        const string = lua.toStringEx(lua.getTop());
+        try std.testing.expectEqualStrings(error_msg, string);
+    }
 }