Unified: Document problematic convenience inheritence corner case

Author: hvitved

unified/ql/test/library-tests/static-name-binding/inheritance.swift

@@ -57,6 +57,18 @@ class M: L {  // $ access=L
 
 class N: L {  // $ access=L
     override init(x: Int) { super.init(x: 0) }  // $ access=Int
+
+    convenience init  // name=N.init_conv
+        (a: Int, b: Int, c: Int)  // $ access=Int
+    {
+        self.init(x: a + b + c)  // $ access=a access=b access=c
+    }
+}
+
+class O: N {  // $ access=N
+    override init(x: Int) {  // $ access=Int
+        super.init(x: x)  // $ access=x
+    }
 }
 
 // Members of base classes can be accessed through derived classes
@@ -94,5 +106,9 @@ func t1() {
 
     let x19 = M.init()  // $ access=M access=M.init access=L.init_conv -- type inference should filter away the `M.init` target
 
-    let x20 = N.init(x: 0)  // $ access=N access=N.init
+    let x20 = N.init(x: 0)  // $ access=N access=N.init access=N.init_conv -- type inference should filter away the `N.init_conv` target
+
+    let x21 = O.init(x: 0)  // $ access=O access=O.init $ MISSING: access=N.init_conv -- type inference should filter away the `N.init_conv` target
+
+    let x22 = O.init(a: 1, b: 2, c: 3)  // $ access=O access=O.init $ MISSING: access=N.init_conv -- type inference should filter away the `O.init` target
 }