smalltalk: respondsTo:/isKindOf:/isMemberOf: + 26 tests

lib/smalltalk/eval.sx

@@ -539,6 +539,32 @@
              (= selector "perform:with:with:with:")
              (= selector "perform:with:with:with:with:"))
           (st-send receiver (str (nth args 0)) (slice args 1 (len args))))
+        ;; respondsTo: aSymbol — searches user method dicts only. Native
+        ;; primitive selectors aren't enumerated, so e.g. `42 respondsTo:
+        ;; #+` returns false. (The send still works because dispatch falls
+        ;; through to st-num-send.) Documented limitation.
+        ((= selector "respondsTo:")
+          (let
+            ((sel-str (str (nth args 0)))
+              (target-cls (if (st-class-ref? receiver) (get receiver :name) cls))
+              (class-side? (st-class-ref? receiver)))
+            (not (= (st-method-lookup target-cls sel-str class-side?) nil))))
+        ;; isKindOf: aClass — true iff the receiver's class chain reaches it.
+        ((= selector "isKindOf:")
+          (let
+            ((arg (nth args 0))
+              (target-cls (if (st-class-ref? receiver) "Metaclass" cls)))
+            (cond
+              ((not (st-class-ref? arg)) false)
+              (else (st-class-inherits-from? target-cls (get arg :name))))))
+        ;; isMemberOf: aClass — exact class match.
+        ((= selector "isMemberOf:")
+          (let
+            ((arg (nth args 0))
+              (target-cls (if (st-class-ref? receiver) "Metaclass" cls)))
+            (cond
+              ((not (st-class-ref? arg)) false)
+              (else (= target-cls (get arg :name))))))
         ((or (= cls "SmallInteger") (= cls "Float"))
           (st-num-send receiver selector args))
         ((or (= cls "String") (= cls "Symbol"))