fixes #2134

compiler/semfields.nim

@@ -156,7 +156,7 @@ proc semForFields(c: PContext, n: PNode, m: TMagic): PNode =
   dec(c.p.nestedLoopCounter)
   # for TR macros this 'while true: ...; break' loop is pretty bad, so
   # we avoid it now if we can:
-  if hasSonWith(stmts, nkBreakStmt):
+  if containsNode(stmts, {nkBreakStmt}):
     var b = newNodeI(nkBreakStmt, n.info)
     b.add(ast.emptyNode)
     stmts.add(b)

tests/fields/tfields_with_break.nim

@@ -0,0 +1,33 @@
+discard """
+  output: '''(one: 1, two: 2, three: 3)
+1
+2
+3
+(one: 4, two: 5, three: 6)
+4
+(one: 7, two: 8, three: 9)
+7
+8
+9'''
+"""
+
+# bug #2134
+type
+    TestType = object
+        one: int
+        two: int
+        three: int
+
+var
+    ab = TestType(one:1, two:2, three:3)
+    ac = TestType(one:4, two:5, three:6)
+    ad = TestType(one:7, two:8, three:9)
+    tstSeq = [ab, ac, ad]
+
+for tstElement in mitems(tstSeq):
+    echo tstElement
+    for tstField in fields(tstElement):
+        #for tstField in [1,2,4,6]:
+        echo tstField
+        if tstField == 4:
+            break