Correctly make vector div by float 0 in a var throw math error in LSL

And add tests so we don't forget it again :)

Fixes #78

Author: HaroldCindy

VM/src/lvmexecute.cpp

@@ -1788,11 +1788,15 @@ static void luau_execute(lua_State* L)
                     setnvalue(ra, res);
                     VM_NEXT();
                 }
-                else if (ttisvector(rb) && ttisnumber(rc) && !LUAU_IS_LSL_VM(L))
+                else if (ttisvector(rb) && ttisnumber(rc))
                 {
-                    // ServerLua: we use different logic in the LSL case.
                     const float* vb = vvalue(rb);
                     float vc = cast_to(float, nvalue(rc));
+                    // ServerLua: In LSL (Mono), vector division by zero is a runtime error.
+                    if (LUAU_UNLIKELY(LUAU_IS_LSL_VM(L) && vc == 0.0))
+                    {
+                        VM_PROTECT(luaG_runerrorL(L, MATH_ERROR_STR));
+                    }
                     setvvalue(ra, vb[0] / vc, vb[1] / vc, vb[2] / vc, vb[3] / vc);
                     VM_NEXT();
                 }

tests/LSL.test.cpp

@@ -1085,8 +1085,11 @@ TEST_CASE("Integer MulAssign Float Valid Contexts")
 TEST_CASE("Division By Zero Error")
 {
     runConformance("div_by_zero.lsl", nullptr, nullptr, nullptr, "Math error");
-    runConformance("float_div_by_zero.lsl", nullptr, nullptr, nullptr, "Math error");
-    runConformance("vector_div_by_zero.lsl", nullptr, nullptr, nullptr, "Math error");
+    runConformance("float_div_by_zero_var.lsl", nullptr, nullptr, nullptr, "Math error");
+    runConformance("float_div_by_zero_k.lsl", nullptr, nullptr, nullptr, "Math error");
+    runConformance("float_div_by_zero_k_rev.lsl", nullptr, nullptr, nullptr, "Math error");
+    runConformance("vector_div_by_zero_k.lsl", nullptr, nullptr, nullptr, "Math error");
+    runConformance("vector_div_by_zero_var.lsl", nullptr, nullptr, nullptr, "Math error");
     runConformance("zero_vector_div_by_zero.lsl", nullptr, nullptr, nullptr, "Math error");
     runConformance("inf_div_inf.lsl", nullptr, nullptr, nullptr, "Math error");
 }

tests/conformance/float_div_by_zero_k.lsl

@@ -0,0 +1,8 @@
+// Test that float division by zero throws a runtime error
+default {
+    state_entry() {
+        float a = 1.0;
+        float c = a / 0.0;  // This should error
+        print((string)c);
+    }
+}

tests/conformance/float_div_by_zero_k_rev.lsl

@@ -0,0 +1,8 @@
+// Test that float division by zero throws a runtime error
+default {
+    state_entry() {
+        float a = 0.0;
+        float c = 1.0 / a;  // This should error
+        print((string)c);
+    }
+}

tests/conformance/float_div_by_zero.lsl …ts/conformance/float_div_by_zero_var.lsltests/conformance/float_div_by_zero.lsl renamed to tests/conformance/float_div_by_zero_var.lsl tests/conformance/float_div_by_zero.lsl renamed to tests/conformance/float_div_by_zero_var.lsl

@@ -0,0 +1,8 @@
+// Test that vector division by zero throws a runtime error
+default {
+    state_entry() {
+        float y = 0.0;
+        vector v = <1, 1, 1> / y;  // This should error
+        print((string)v);
+    }
+}