more unit tests

server/src/tests/__snapshots__/compiler.spec.ts.snap

@@ -450,6 +450,8 @@ Found 1 error in server/src/tests/cases/compiler/typePredicate1.c:7
 "
 `;
 
+exports[`Compiler compiler/typePredicate2.c Reports correct errors for compiler/typePredicate2.c: diags-compiler/typePredicate2.c 1`] = `""`;
+
 exports[`Compiler compiler/unionTypes.c Reports correct errors for compiler/unionTypes.c: diags-compiler/unionTypes.c 1`] = `""`;
 
 exports[`Compiler compiler/utf8.c Reports correct errors for compiler/utf8.c: diags-compiler/utf8.c 1`] = `""`;

server/src/tests/cases/compiler/typePredicate2.c

@@ -0,0 +1,17 @@
+test() {
+    mixed o;
+    if (fn(o)) {        
+        int id = o->query_number();
+    }
+}
+
+/**
+ * 
+ * @param o 
+ * @returns {o is "object.c"}
+ */
+fn(mixed o) {
+    return 1;
+}
+
+// @files: object.c