Swift: Add tests for array append/insert.

Author: geoffw0

swift/ql/test/library-tests/dataflow/taint/libraries/array.swift

@@ -0,0 +1,43 @@
+
+// --- stubs ---
+
+// --- tests ---
+
+func source(_ label: String) -> Int { return 0 }
+func sink(arg: Any) {}
+
+// ---
+
+func testArray() {
+  let arrClean = Array<Int>()
+
+  var arr1 = Array<Int>()
+  arr1.append(1)
+  sink(arg: arr1[arr1.endIndex - 1])
+  arr1.append(source("int1"))
+  sink(arg: arr1[arr1.endIndex - 1]) // $ tainted=int1
+
+  var arr2 = Array<Int>()
+  arr2.append(contentsOf: arrClean)
+  sink(arg: arr2[arr2.endIndex - 1])
+  arr2.append(contentsOf: arr1)
+  sink(arg: arr2[arr2.endIndex - 1]) // $ tainted=int1
+
+  var arr3 = Array<Int>()
+  arr3.insert(1, at: 0)
+  sink(arg: arr3[0])
+  arr3.insert(source("int3"), at: 0)
+  sink(arg: arr3[0]) // $ tainted=int3
+
+  var arr4 = Array<Int>()
+  arr4.insert(contentsOf: arrClean, at: 0)
+  sink(arg: arr4[0])
+  arr4.insert(contentsOf: arr3, at: 0)
+  sink(arg: arr4[0]) // $ MISSING: tainted=int3
+
+  var arr5 = Array<Int>()
+  arr5.insert(contentsOf: 1...10, at: 0)
+  sink(arg: arr5[arr5.endIndex - 1])
+  arr5.insert(contentsOf: 1...source("int5"), at: 0)
+  sink(arg: arr5[arr5.endIndex - 1]) // $ MISSING: tainted=int5
+}