feat: add comparison functions to the 5.1 api

natecraddock · natecraddock · commit 1bfbc5941766 · 2023-02-15T21:49:24.000-07:00
Adds equal and lessThan
diff --git a/src/ziglua-5.1/lib.zig b/src/ziglua-5.1/lib.zig
@@ -387,6 +387,13 @@ pub const Lua = struct {
         if (c.lua_dump(lua.state, writer, data) != 0) return error.Fail;
     }
 
+    /// Returns true if the two values at the indexes are equal following the semantics of the
+    /// Lua == operator.
+    /// See https://www.lua.org/manual/5.1/manual.html#lua_equal
+    pub fn equal(lua: *Lua, index1: i32, index2: i32) bool {
+        return c.lua_equal(lua.state, index1, index2) == 1;
+    }
+
     /// Raises a Lua error using the value at the top of the stack as the error object
     /// Does a longjump and therefore never returns
     /// See https://www.lua.org/manual/5.4/manual.html#lua_error
@@ -573,6 +580,12 @@ pub const Lua = struct {
         return c.lua_isuserdata(lua.state, index) != 0;
     }
 
+    /// Returns true if the value at index1 is smaller than the value at index2, following the
+    /// semantics of the Lua < operator.
+    pub fn lessThan(lua: *Lua, index1: i32, index2: i32) bool {
+        return c.lua_lessthan(lua.state, index1, index2) == 1;
+    }
+
     /// Loads a Lua chunk without running it
     /// If there are no errors, pushes the compiled chunk on the top of the stack as a function
     /// See https://www.lua.org/manual/5.4/manual.html#lua_load
diff --git a/src/ziglua-5.1/tests.zig b/src/ziglua-5.1/tests.zig
@@ -281,6 +281,21 @@ test "filling and checking the stack" {
     try expectEqual(@as(i32, 40), lua.getTop());
 }
 
+test "comparisions" {
+    var lua = try Lua.init(testing.allocator);
+    defer lua.deinit();
+
+    lua.pushInteger(1);
+    lua.pushInteger(2);
+
+    try testing.expect(!lua.equal(1, 2));
+    try testing.expect(lua.lessThan(1, 2));
+
+    lua.pushInteger(2);
+
+    try testing.expect(lua.equal(2, 3));
+}
+
 test "stack manipulation" {
     var lua = try Lua.init(testing.allocator);
     defer lua.deinit();
