added check for iterator method in foreach (closes #866)

test case contributed by Wareditor

Co-authored-by: Wareditor <[email protected]>

Author: peq

de.peeeq.wurstscript/src/main/java/de/peeeq/wurstscript/attributes/AttrForEachStatement.java

@@ -24,6 +24,13 @@ public static Optional<FuncLink> calcIterator(StmtForIn forEach) {
         // find the 'hasNext' function without parameters
         if (!iteratorFunc.isPresent()) {
             forEach.getIn().addError("For loop target " + itrType + " doesn't provide a iterator() function");
+        } else {
+            FuncLink f = iteratorFunc.get();
+            if (f.isStatic() && !itrType.isStaticRef()) {
+                iterationTarget.addError("Cannot use static iterator method from " + itrType + " on dynamic value.");
+            } else if (!f.isStatic() && itrType.isStaticRef()) {
+                iterationTarget.addError("Cannot use dynamic iterator method from " + itrType + " without a dynamic value.");
+            }
         }
         return iteratorFunc;
     }
@@ -36,6 +43,11 @@ public static Optional<FuncLink> calcHasNext(StmtForEach forEach) {
         Optional<FuncLink> nextFunc = hasNext.stream().filter(nl -> nl.getParameterTypes().isEmpty()).findFirst();
         if (!nextFunc.isPresent()) {
             forEach.getIn().addError("For loop iterator doesn't provide a hasNext() function that returns boolean");
+        } else {
+            FuncLink f = nextFunc.get();
+            if (f.isStatic()) {
+                forEach.addError("Cannot use a foreach loop here, because the 'hasNext' method " + iteratorType + " is static.");
+            }
         }
         return nextFunc;
     }
@@ -49,6 +61,11 @@ public static Optional<FuncLink> calcGetNext(StmtForEach forEach) {
         Optional<FuncLink> nextFunc = next.stream().filter(nl -> nl.getParameterTypes().isEmpty()).findFirst();
         if (!nextFunc.isPresent()) {
             forEach.getIn().addError("Target of for-loop '" + forEach.getIn().attrTyp().getName() + "' doesn't provide a proper next() function");
+        } else {
+            FuncLink f = nextFunc.get();
+            if (f.isStatic()) {
+                forEach.addError("Cannot use a foreach loop here, because the 'next' method " + iteratorType + " is static.");
+            }
         }
         return nextFunc;
     }
@@ -65,6 +82,11 @@ public static Optional<FuncLink> calcClose(StmtForEach forEach) {
         Optional<FuncLink> closeFunc = close.stream().filter(nl -> nl.getParameterTypes().isEmpty()).findFirst();
         if (!closeFunc.isPresent()) {
             forEach.getIn().addError("Target of for-loop <" + forEach.getIn().attrTyp().getName() + " doesn't provide a proper close() function");
+        } else {
+            FuncLink f = closeFunc.get();
+            if (f.isStatic()) {
+                forEach.addError("Cannot use a foreach loop here, because the 'close' method " + iteratorType + " is static.");
+            }
         }
         return closeFunc;
     }

de.peeeq.wurstscript/src/main/java/de/peeeq/wurstscript/types/WurstTypeNamedScope.java

@@ -237,4 +237,4 @@ protected boolean isNullable() {
     }
 
 
-}
+}

de.peeeq.wurstscript/src/test/java/tests/wurstscript/tests/NewFeatureTests.java

@@ -648,6 +648,31 @@ public void testForInCloseBeforeReturn() {
         );
     }
 
+    @Test
+    public void testIteratorStatic() { // see #866
+        testAssertErrorsLines(false, "Cannot use static iterator method from A on dynamic value.",
+            "package Test",
+            "class A",
+            "    static B itr",
+            "    static function iterator() returns B",
+            "        return itr",
+            "    construct()",
+            "        itr = new B()",
+            "",
+            "public class B",
+            "    construct()",
+            "    function hasNext() returns boolean",
+            "        return true",
+            "    function next() returns int",
+            "        return 0",
+            "    function close()",
+            "",
+            "init",
+            "    let list = new A()",
+            "    for i in list"
+        );
+    }
+
     @Test
     public void testIfNotDefinedAnnotation1() {
         testAssertOkLines(true,