diff --git a/swift/ql/lib/codeql/swift/dataflow/internal/DataFlowPrivate.qll b/swift/ql/lib/codeql/swift/dataflow/internal/DataFlowPrivate.qll
index c1984e0b80f7..c4a2f2dfd2fd 100644
--- a/swift/ql/lib/codeql/swift/dataflow/internal/DataFlowPrivate.qll
+++ b/swift/ql/lib/codeql/swift/dataflow/internal/DataFlowPrivate.qll
@@ -108,12 +108,20 @@ private module Cached {
       localFlowSsaInput(nodeFrom, def, nodeTo.asDefinition())
     )
     or
+    // flow through writes to inout parameters
     exists(ParamReturnKind kind, ExprCfgNode arg |
       arg = nodeFrom.(InOutUpdateNode).getCall(kind).asCall().getArgument(kind.getIndex()) and
       nodeTo.asDefinition().(Ssa::WriteDefinition).isInoutDef(arg)
     )
     or
+    // flow through `&` (inout argument)
     nodeFrom.asExpr() = nodeTo.asExpr().(InOutExpr).getSubExpr()
+    or
+    // flow through `try!` and similar constructs
+    nodeFrom.asExpr() = nodeTo.asExpr().(AnyTryExpr).getSubExpr()
+    or
+    // flow through `!`
+    nodeFrom.asExpr() = nodeTo.asExpr().(ForceValueExpr).getSubExpr()
   }
 
   /**
diff --git a/swift/ql/lib/codeql/swift/dataflow/internal/TaintTrackingPrivate.qll b/swift/ql/lib/codeql/swift/dataflow/internal/TaintTrackingPrivate.qll
index 58e29b61bba4..1292e0cf1814 100644
--- a/swift/ql/lib/codeql/swift/dataflow/internal/TaintTrackingPrivate.qll
+++ b/swift/ql/lib/codeql/swift/dataflow/internal/TaintTrackingPrivate.qll
@@ -41,6 +41,23 @@ private module Cached {
       nodeTo.asExpr() = interpolated and
       nodeFrom.asExpr() = interpolated.getAppendingExpr()
     )
+    or
+    // allow flow through string concatenation.
+    exists(AddExpr ae |
+      ae.getAnOperand() = nodeFrom.asExpr() and
+      ae = nodeTo.asExpr() and
+      ae.getType().getName() = "String"
+    )
+    or
+    // allow flow through `URL.init`.
+    exists(CallExpr call, ClassDecl c, AbstractFunctionDecl f |
+      c.getName() = "URL" and
+      c.getAMember() = f and
+      f.getName() = ["init(string:)", "init(string:relativeTo:)"] and
+      call.getFunction().(ApplyExpr).getStaticTarget() = f and
+      nodeFrom.asExpr() = call.getAnArgument().getExpr() and
+      nodeTo.asExpr() = call
+    )
   }
 
   /**
diff --git a/swift/ql/src/queries/Security/CWE-079/UnsafeWebViewFetch.ql b/swift/ql/src/queries/Security/CWE-079/UnsafeWebViewFetch.ql
index b952a0c74c38..37bf5ec21c47 100644
--- a/swift/ql/src/queries/Security/CWE-079/UnsafeWebViewFetch.ql
+++ b/swift/ql/src/queries/Security/CWE-079/UnsafeWebViewFetch.ql
@@ -81,30 +81,6 @@ class UnsafeWebViewFetchConfig extends TaintTracking::Configuration {
     node instanceof Sink or
     node.asExpr() = any(Sink s).getBaseUrl()
   }
-
-  override predicate isAdditionalTaintStep(DataFlow::Node node1, DataFlow::Node node2) {
-    // allow flow through `try!` and similar constructs
-    // TODO: this should probably be part of DataFlow / TaintTracking.
-    node1.asExpr() = node2.asExpr().(AnyTryExpr).getSubExpr()
-    or
-    // allow flow through `!`
-    // TODO: this should probably be part of DataFlow / TaintTracking.
-    node1.asExpr() = node2.asExpr().(ForceValueExpr).getSubExpr()
-    or
-    // allow flow through string concatenation.
-    // TODO: this should probably be part of TaintTracking.
-    node2.asExpr().(AddExpr).getAnOperand() = node1.asExpr()
-    or
-    // allow flow through `URL.init`.
-    exists(CallExpr call, ClassDecl c, AbstractFunctionDecl f |
-      c.getName() = "URL" and
-      c.getAMember() = f and
-      f.getName() = ["init(string:)", "init(string:relativeTo:)"] and
-      call.getFunction().(ApplyExpr).getStaticTarget() = f and
-      node1.asExpr() = call.getAnArgument().getExpr() and
-      node2.asExpr() = call
-    )
-  }
 }
 
 from
diff --git a/swift/ql/test/library-tests/dataflow/taint/LocalTaint.expected b/swift/ql/test/library-tests/dataflow/taint/LocalTaint.expected
index 6796c2e8c40a..a7c44e9b5667 100644
--- a/swift/ql/test/library-tests/dataflow/taint/LocalTaint.expected
+++ b/swift/ql/test/library-tests/dataflow/taint/LocalTaint.expected
@@ -1,121 +1,222 @@
-| file://:0:0:0:0 | Phi | test.swift:7:14:7:14 | $interpolation |
-| file://:0:0:0:0 | Phi | test.swift:9:14:9:14 | $interpolation |
-| file://:0:0:0:0 | Phi | test.swift:11:14:11:14 | $interpolation |
-| file://:0:0:0:0 | Phi | test.swift:14:14:14:14 | $interpolation |
-| file://:0:0:0:0 | Phi | test.swift:16:14:16:14 | $interpolation |
-| file://:0:0:0:0 | Phi | test.swift:18:14:18:14 | $interpolation |
-| file://:0:0:0:0 | Phi | test.swift:21:14:21:14 | $interpolation |
-| test.swift:5:7:5:7 | WriteDef | test.swift:7:16:7:16 | x |
-| test.swift:5:11:5:18 | call to source() | test.swift:5:7:5:7 | WriteDef |
-| test.swift:7:13:7:13 | WriteDef | file://:0:0:0:0 | Phi |
-| test.swift:7:14:7:14 | $interpolation | test.swift:7:14:7:14 | &... |
-| test.swift:7:14:7:14 | : &... | test.swift:7:14:7:14 | WriteDef |
-| test.swift:7:14:7:14 | WriteDef | test.swift:7:15:7:15 | $interpolation |
-| test.swift:7:15:7:15 | $interpolation | test.swift:7:15:7:15 | &... |
-| test.swift:7:15:7:15 | : &... | test.swift:7:15:7:15 | WriteDef |
-| test.swift:7:15:7:15 | WriteDef | test.swift:7:18:7:18 | $interpolation |
-| test.swift:7:16:7:16 | x | test.swift:9:16:9:16 | x |
-| test.swift:7:18:7:18 | $interpolation | test.swift:7:18:7:18 | &... |
-| test.swift:7:18:7:18 | : &... | test.swift:7:18:7:18 | WriteDef |
-| test.swift:7:18:7:18 | WriteDef | test.swift:7:13:7:13 | TapExpr |
-| test.swift:9:13:9:13 | WriteDef | file://:0:0:0:0 | Phi |
-| test.swift:9:14:9:14 | $interpolation | test.swift:9:14:9:14 | &... |
-| test.swift:9:14:9:14 | : &... | test.swift:9:14:9:14 | WriteDef |
-| test.swift:9:14:9:14 | WriteDef | test.swift:9:15:9:15 | $interpolation |
-| test.swift:9:15:9:15 | $interpolation | test.swift:9:15:9:15 | &... |
-| test.swift:9:15:9:15 | : &... | test.swift:9:15:9:15 | WriteDef |
-| test.swift:9:15:9:15 | WriteDef | test.swift:9:18:9:18 | $interpolation |
-| test.swift:9:16:9:16 | x | test.swift:9:21:9:21 | x |
-| test.swift:9:18:9:18 | $interpolation | test.swift:9:18:9:18 | &... |
-| test.swift:9:18:9:18 | : &... | test.swift:9:18:9:18 | WriteDef |
-| test.swift:9:18:9:18 | WriteDef | test.swift:9:20:9:20 | $interpolation |
-| test.swift:9:20:9:20 | $interpolation | test.swift:9:20:9:20 | &... |
-| test.swift:9:20:9:20 | : &... | test.swift:9:20:9:20 | WriteDef |
-| test.swift:9:20:9:20 | WriteDef | test.swift:9:23:9:23 | $interpolation |
-| test.swift:9:21:9:21 | x | test.swift:11:16:11:16 | x |
-| test.swift:9:23:9:23 | $interpolation | test.swift:9:23:9:23 | &... |
-| test.swift:9:23:9:23 | : &... | test.swift:9:23:9:23 | WriteDef |
-| test.swift:9:23:9:23 | WriteDef | test.swift:9:13:9:13 | TapExpr |
-| test.swift:11:13:11:13 | WriteDef | file://:0:0:0:0 | Phi |
-| test.swift:11:14:11:14 | $interpolation | test.swift:11:14:11:14 | &... |
-| test.swift:11:14:11:14 | : &... | test.swift:11:14:11:14 | WriteDef |
-| test.swift:11:14:11:14 | WriteDef | test.swift:11:15:11:15 | $interpolation |
-| test.swift:11:15:11:15 | $interpolation | test.swift:11:15:11:15 | &... |
-| test.swift:11:15:11:15 | : &... | test.swift:11:15:11:15 | WriteDef |
-| test.swift:11:15:11:15 | WriteDef | test.swift:11:18:11:18 | $interpolation |
-| test.swift:11:16:11:16 | x | test.swift:11:26:11:26 | x |
-| test.swift:11:18:11:18 | $interpolation | test.swift:11:18:11:18 | &... |
-| test.swift:11:18:11:18 | : &... | test.swift:11:18:11:18 | WriteDef |
-| test.swift:11:18:11:18 | WriteDef | test.swift:11:20:11:20 | $interpolation |
-| test.swift:11:20:11:20 | $interpolation | test.swift:11:20:11:20 | &... |
-| test.swift:11:20:11:20 | : &... | test.swift:11:20:11:20 | WriteDef |
-| test.swift:11:20:11:20 | WriteDef | test.swift:11:23:11:23 | $interpolation |
-| test.swift:11:23:11:23 | $interpolation | test.swift:11:23:11:23 | &... |
-| test.swift:11:23:11:23 | : &... | test.swift:11:23:11:23 | WriteDef |
-| test.swift:11:23:11:23 | WriteDef | test.swift:11:25:11:25 | $interpolation |
-| test.swift:11:25:11:25 | $interpolation | test.swift:11:25:11:25 | &... |
-| test.swift:11:25:11:25 | : &... | test.swift:11:25:11:25 | WriteDef |
-| test.swift:11:25:11:25 | WriteDef | test.swift:11:28:11:28 | $interpolation |
-| test.swift:11:26:11:26 | x | test.swift:16:16:16:16 | x |
-| test.swift:11:28:11:28 | $interpolation | test.swift:11:28:11:28 | &... |
-| test.swift:11:28:11:28 | : &... | test.swift:11:28:11:28 | WriteDef |
-| test.swift:11:28:11:28 | WriteDef | test.swift:11:13:11:13 | TapExpr |
-| test.swift:13:7:13:7 | WriteDef | test.swift:14:16:14:16 | y |
-| test.swift:13:11:13:11 | 42 | test.swift:13:7:13:7 | WriteDef |
-| test.swift:14:13:14:13 | WriteDef | file://:0:0:0:0 | Phi |
-| test.swift:14:14:14:14 | $interpolation | test.swift:14:14:14:14 | &... |
-| test.swift:14:14:14:14 | : &... | test.swift:14:14:14:14 | WriteDef |
-| test.swift:14:14:14:14 | WriteDef | test.swift:14:15:14:15 | $interpolation |
-| test.swift:14:15:14:15 | $interpolation | test.swift:14:15:14:15 | &... |
-| test.swift:14:15:14:15 | : &... | test.swift:14:15:14:15 | WriteDef |
-| test.swift:14:15:14:15 | WriteDef | test.swift:14:18:14:18 | $interpolation |
-| test.swift:14:16:14:16 | y | test.swift:16:27:16:27 | y |
-| test.swift:14:18:14:18 | $interpolation | test.swift:14:18:14:18 | &... |
-| test.swift:14:18:14:18 | : &... | test.swift:14:18:14:18 | WriteDef |
-| test.swift:14:18:14:18 | WriteDef | test.swift:14:13:14:13 | TapExpr |
-| test.swift:16:13:16:13 | WriteDef | file://:0:0:0:0 | Phi |
-| test.swift:16:14:16:14 | $interpolation | test.swift:16:14:16:14 | &... |
-| test.swift:16:14:16:14 | : &... | test.swift:16:14:16:14 | WriteDef |
-| test.swift:16:14:16:14 | WriteDef | test.swift:16:15:16:15 | $interpolation |
-| test.swift:16:15:16:15 | $interpolation | test.swift:16:15:16:15 | &... |
-| test.swift:16:15:16:15 | : &... | test.swift:16:15:16:15 | WriteDef |
-| test.swift:16:15:16:15 | WriteDef | test.swift:16:18:16:18 | $interpolation |
-| test.swift:16:16:16:16 | x | test.swift:18:27:18:27 | x |
-| test.swift:16:18:16:18 | $interpolation | test.swift:16:18:16:18 | &... |
-| test.swift:16:18:16:18 | : &... | test.swift:16:18:16:18 | WriteDef |
-| test.swift:16:18:16:18 | WriteDef | test.swift:16:26:16:26 | $interpolation |
-| test.swift:16:26:16:26 | $interpolation | test.swift:16:26:16:26 | &... |
-| test.swift:16:26:16:26 | : &... | test.swift:16:26:16:26 | WriteDef |
-| test.swift:16:26:16:26 | WriteDef | test.swift:16:29:16:29 | $interpolation |
-| test.swift:16:27:16:27 | y | test.swift:18:16:18:16 | y |
-| test.swift:16:29:16:29 | $interpolation | test.swift:16:29:16:29 | &... |
-| test.swift:16:29:16:29 | : &... | test.swift:16:29:16:29 | WriteDef |
-| test.swift:16:29:16:29 | WriteDef | test.swift:16:13:16:13 | TapExpr |
-| test.swift:18:13:18:13 | WriteDef | file://:0:0:0:0 | Phi |
-| test.swift:18:14:18:14 | $interpolation | test.swift:18:14:18:14 | &... |
-| test.swift:18:14:18:14 | : &... | test.swift:18:14:18:14 | WriteDef |
-| test.swift:18:14:18:14 | WriteDef | test.swift:18:15:18:15 | $interpolation |
-| test.swift:18:15:18:15 | $interpolation | test.swift:18:15:18:15 | &... |
-| test.swift:18:15:18:15 | : &... | test.swift:18:15:18:15 | WriteDef |
-| test.swift:18:15:18:15 | WriteDef | test.swift:18:18:18:18 | $interpolation |
-| test.swift:18:18:18:18 | $interpolation | test.swift:18:18:18:18 | &... |
-| test.swift:18:18:18:18 | : &... | test.swift:18:18:18:18 | WriteDef |
-| test.swift:18:18:18:18 | WriteDef | test.swift:18:26:18:26 | $interpolation |
-| test.swift:18:26:18:26 | $interpolation | test.swift:18:26:18:26 | &... |
-| test.swift:18:26:18:26 | : &... | test.swift:18:26:18:26 | WriteDef |
-| test.swift:18:26:18:26 | WriteDef | test.swift:18:29:18:29 | $interpolation |
-| test.swift:18:29:18:29 | $interpolation | test.swift:18:29:18:29 | &... |
-| test.swift:18:29:18:29 | : &... | test.swift:18:29:18:29 | WriteDef |
-| test.swift:18:29:18:29 | WriteDef | test.swift:18:13:18:13 | TapExpr |
-| test.swift:20:3:20:7 | WriteDef | test.swift:21:16:21:16 | x |
-| test.swift:20:7:20:7 | 0 | test.swift:20:3:20:7 | WriteDef |
-| test.swift:21:13:21:13 | WriteDef | file://:0:0:0:0 | Phi |
-| test.swift:21:14:21:14 | $interpolation | test.swift:21:14:21:14 | &... |
-| test.swift:21:14:21:14 | : &... | test.swift:21:14:21:14 | WriteDef |
-| test.swift:21:14:21:14 | WriteDef | test.swift:21:15:21:15 | $interpolation |
-| test.swift:21:15:21:15 | $interpolation | test.swift:21:15:21:15 | &... |
-| test.swift:21:15:21:15 | : &... | test.swift:21:15:21:15 | WriteDef |
-| test.swift:21:15:21:15 | WriteDef | test.swift:21:18:21:18 | $interpolation |
-| test.swift:21:18:21:18 | $interpolation | test.swift:21:18:21:18 | &... |
-| test.swift:21:18:21:18 | : &... | test.swift:21:18:21:18 | WriteDef |
-| test.swift:21:18:21:18 | WriteDef | test.swift:21:13:21:13 | TapExpr |
+| data.swift:12:6:12:6 | WriteDef | data.swift:16:12:16:12 | dataClean |
+| data.swift:12:18:12:36 | call to ... | data.swift:12:6:12:6 | WriteDef |
+| data.swift:13:6:13:6 | WriteDef | data.swift:14:26:14:26 | dataTainted |
+| data.swift:13:20:13:38 | call to ... | data.swift:13:6:13:6 | WriteDef |
+| data.swift:14:6:14:6 | WriteDef | data.swift:18:12:18:12 | dataTainted2 |
+| data.swift:14:21:14:37 | call to ... | data.swift:14:6:14:6 | WriteDef |
+| data.swift:14:26:14:26 | dataTainted | data.swift:17:12:17:12 | dataTainted |
+| data.swift:16:12:16:12 | dataClean | data.swift:20:33:20:33 | dataClean |
+| file://:0:0:0:0 | Phi | string.swift:7:14:7:14 | $interpolation |
+| file://:0:0:0:0 | Phi | string.swift:9:14:9:14 | $interpolation |
+| file://:0:0:0:0 | Phi | string.swift:11:14:11:14 | $interpolation |
+| file://:0:0:0:0 | Phi | string.swift:14:14:14:14 | $interpolation |
+| file://:0:0:0:0 | Phi | string.swift:16:14:16:14 | $interpolation |
+| file://:0:0:0:0 | Phi | string.swift:18:14:18:14 | $interpolation |
+| file://:0:0:0:0 | Phi | string.swift:21:14:21:14 | $interpolation |
+| string.swift:5:7:5:7 | WriteDef | string.swift:7:16:7:16 | x |
+| string.swift:5:11:5:18 | call to source() | string.swift:5:7:5:7 | WriteDef |
+| string.swift:7:13:7:13 | WriteDef | file://:0:0:0:0 | Phi |
+| string.swift:7:14:7:14 | $interpolation | string.swift:7:14:7:14 | &... |
+| string.swift:7:14:7:14 | : &... | string.swift:7:14:7:14 | WriteDef |
+| string.swift:7:14:7:14 | WriteDef | string.swift:7:15:7:15 | $interpolation |
+| string.swift:7:15:7:15 | $interpolation | string.swift:7:15:7:15 | &... |
+| string.swift:7:15:7:15 | : &... | string.swift:7:15:7:15 | WriteDef |
+| string.swift:7:15:7:15 | WriteDef | string.swift:7:18:7:18 | $interpolation |
+| string.swift:7:16:7:16 | x | string.swift:9:16:9:16 | x |
+| string.swift:7:18:7:18 | $interpolation | string.swift:7:18:7:18 | &... |
+| string.swift:7:18:7:18 | : &... | string.swift:7:18:7:18 | WriteDef |
+| string.swift:7:18:7:18 | WriteDef | string.swift:7:13:7:13 | TapExpr |
+| string.swift:9:13:9:13 | WriteDef | file://:0:0:0:0 | Phi |
+| string.swift:9:14:9:14 | $interpolation | string.swift:9:14:9:14 | &... |
+| string.swift:9:14:9:14 | : &... | string.swift:9:14:9:14 | WriteDef |
+| string.swift:9:14:9:14 | WriteDef | string.swift:9:15:9:15 | $interpolation |
+| string.swift:9:15:9:15 | $interpolation | string.swift:9:15:9:15 | &... |
+| string.swift:9:15:9:15 | : &... | string.swift:9:15:9:15 | WriteDef |
+| string.swift:9:15:9:15 | WriteDef | string.swift:9:18:9:18 | $interpolation |
+| string.swift:9:16:9:16 | x | string.swift:9:21:9:21 | x |
+| string.swift:9:18:9:18 | $interpolation | string.swift:9:18:9:18 | &... |
+| string.swift:9:18:9:18 | : &... | string.swift:9:18:9:18 | WriteDef |
+| string.swift:9:18:9:18 | WriteDef | string.swift:9:20:9:20 | $interpolation |
+| string.swift:9:20:9:20 | $interpolation | string.swift:9:20:9:20 | &... |
+| string.swift:9:20:9:20 | : &... | string.swift:9:20:9:20 | WriteDef |
+| string.swift:9:20:9:20 | WriteDef | string.swift:9:23:9:23 | $interpolation |
+| string.swift:9:21:9:21 | x | string.swift:11:16:11:16 | x |
+| string.swift:9:23:9:23 | $interpolation | string.swift:9:23:9:23 | &... |
+| string.swift:9:23:9:23 | : &... | string.swift:9:23:9:23 | WriteDef |
+| string.swift:9:23:9:23 | WriteDef | string.swift:9:13:9:13 | TapExpr |
+| string.swift:11:13:11:13 | WriteDef | file://:0:0:0:0 | Phi |
+| string.swift:11:14:11:14 | $interpolation | string.swift:11:14:11:14 | &... |
+| string.swift:11:14:11:14 | : &... | string.swift:11:14:11:14 | WriteDef |
+| string.swift:11:14:11:14 | WriteDef | string.swift:11:15:11:15 | $interpolation |
+| string.swift:11:15:11:15 | $interpolation | string.swift:11:15:11:15 | &... |
+| string.swift:11:15:11:15 | : &... | string.swift:11:15:11:15 | WriteDef |
+| string.swift:11:15:11:15 | WriteDef | string.swift:11:18:11:18 | $interpolation |
+| string.swift:11:16:11:16 | x | string.swift:11:26:11:26 | x |
+| string.swift:11:18:11:18 | $interpolation | string.swift:11:18:11:18 | &... |
+| string.swift:11:18:11:18 | : &... | string.swift:11:18:11:18 | WriteDef |
+| string.swift:11:18:11:18 | WriteDef | string.swift:11:20:11:20 | $interpolation |
+| string.swift:11:20:11:20 | $interpolation | string.swift:11:20:11:20 | &... |
+| string.swift:11:20:11:20 | : &... | string.swift:11:20:11:20 | WriteDef |
+| string.swift:11:20:11:20 | WriteDef | string.swift:11:23:11:23 | $interpolation |
+| string.swift:11:23:11:23 | $interpolation | string.swift:11:23:11:23 | &... |
+| string.swift:11:23:11:23 | : &... | string.swift:11:23:11:23 | WriteDef |
+| string.swift:11:23:11:23 | WriteDef | string.swift:11:25:11:25 | $interpolation |
+| string.swift:11:25:11:25 | $interpolation | string.swift:11:25:11:25 | &... |
+| string.swift:11:25:11:25 | : &... | string.swift:11:25:11:25 | WriteDef |
+| string.swift:11:25:11:25 | WriteDef | string.swift:11:28:11:28 | $interpolation |
+| string.swift:11:26:11:26 | x | string.swift:16:16:16:16 | x |
+| string.swift:11:28:11:28 | $interpolation | string.swift:11:28:11:28 | &... |
+| string.swift:11:28:11:28 | : &... | string.swift:11:28:11:28 | WriteDef |
+| string.swift:11:28:11:28 | WriteDef | string.swift:11:13:11:13 | TapExpr |
+| string.swift:13:7:13:7 | WriteDef | string.swift:14:16:14:16 | y |
+| string.swift:13:11:13:11 | 42 | string.swift:13:7:13:7 | WriteDef |
+| string.swift:14:13:14:13 | WriteDef | file://:0:0:0:0 | Phi |
+| string.swift:14:14:14:14 | $interpolation | string.swift:14:14:14:14 | &... |
+| string.swift:14:14:14:14 | : &... | string.swift:14:14:14:14 | WriteDef |
+| string.swift:14:14:14:14 | WriteDef | string.swift:14:15:14:15 | $interpolation |
+| string.swift:14:15:14:15 | $interpolation | string.swift:14:15:14:15 | &... |
+| string.swift:14:15:14:15 | : &... | string.swift:14:15:14:15 | WriteDef |
+| string.swift:14:15:14:15 | WriteDef | string.swift:14:18:14:18 | $interpolation |
+| string.swift:14:16:14:16 | y | string.swift:16:27:16:27 | y |
+| string.swift:14:18:14:18 | $interpolation | string.swift:14:18:14:18 | &... |
+| string.swift:14:18:14:18 | : &... | string.swift:14:18:14:18 | WriteDef |
+| string.swift:14:18:14:18 | WriteDef | string.swift:14:13:14:13 | TapExpr |
+| string.swift:16:13:16:13 | WriteDef | file://:0:0:0:0 | Phi |
+| string.swift:16:14:16:14 | $interpolation | string.swift:16:14:16:14 | &... |
+| string.swift:16:14:16:14 | : &... | string.swift:16:14:16:14 | WriteDef |
+| string.swift:16:14:16:14 | WriteDef | string.swift:16:15:16:15 | $interpolation |
+| string.swift:16:15:16:15 | $interpolation | string.swift:16:15:16:15 | &... |
+| string.swift:16:15:16:15 | : &... | string.swift:16:15:16:15 | WriteDef |
+| string.swift:16:15:16:15 | WriteDef | string.swift:16:18:16:18 | $interpolation |
+| string.swift:16:16:16:16 | x | string.swift:18:27:18:27 | x |
+| string.swift:16:18:16:18 | $interpolation | string.swift:16:18:16:18 | &... |
+| string.swift:16:18:16:18 | : &... | string.swift:16:18:16:18 | WriteDef |
+| string.swift:16:18:16:18 | WriteDef | string.swift:16:26:16:26 | $interpolation |
+| string.swift:16:26:16:26 | $interpolation | string.swift:16:26:16:26 | &... |
+| string.swift:16:26:16:26 | : &... | string.swift:16:26:16:26 | WriteDef |
+| string.swift:16:26:16:26 | WriteDef | string.swift:16:29:16:29 | $interpolation |
+| string.swift:16:27:16:27 | y | string.swift:18:16:18:16 | y |
+| string.swift:16:29:16:29 | $interpolation | string.swift:16:29:16:29 | &... |
+| string.swift:16:29:16:29 | : &... | string.swift:16:29:16:29 | WriteDef |
+| string.swift:16:29:16:29 | WriteDef | string.swift:16:13:16:13 | TapExpr |
+| string.swift:18:13:18:13 | WriteDef | file://:0:0:0:0 | Phi |
+| string.swift:18:14:18:14 | $interpolation | string.swift:18:14:18:14 | &... |
+| string.swift:18:14:18:14 | : &... | string.swift:18:14:18:14 | WriteDef |
+| string.swift:18:14:18:14 | WriteDef | string.swift:18:15:18:15 | $interpolation |
+| string.swift:18:15:18:15 | $interpolation | string.swift:18:15:18:15 | &... |
+| string.swift:18:15:18:15 | : &... | string.swift:18:15:18:15 | WriteDef |
+| string.swift:18:15:18:15 | WriteDef | string.swift:18:18:18:18 | $interpolation |
+| string.swift:18:18:18:18 | $interpolation | string.swift:18:18:18:18 | &... |
+| string.swift:18:18:18:18 | : &... | string.swift:18:18:18:18 | WriteDef |
+| string.swift:18:18:18:18 | WriteDef | string.swift:18:26:18:26 | $interpolation |
+| string.swift:18:26:18:26 | $interpolation | string.swift:18:26:18:26 | &... |
+| string.swift:18:26:18:26 | : &... | string.swift:18:26:18:26 | WriteDef |
+| string.swift:18:26:18:26 | WriteDef | string.swift:18:29:18:29 | $interpolation |
+| string.swift:18:29:18:29 | $interpolation | string.swift:18:29:18:29 | &... |
+| string.swift:18:29:18:29 | : &... | string.swift:18:29:18:29 | WriteDef |
+| string.swift:18:29:18:29 | WriteDef | string.swift:18:13:18:13 | TapExpr |
+| string.swift:20:3:20:7 | WriteDef | string.swift:21:16:21:16 | x |
+| string.swift:20:7:20:7 | 0 | string.swift:20:3:20:7 | WriteDef |
+| string.swift:21:13:21:13 | WriteDef | file://:0:0:0:0 | Phi |
+| string.swift:21:14:21:14 | $interpolation | string.swift:21:14:21:14 | &... |
+| string.swift:21:14:21:14 | : &... | string.swift:21:14:21:14 | WriteDef |
+| string.swift:21:14:21:14 | WriteDef | string.swift:21:15:21:15 | $interpolation |
+| string.swift:21:15:21:15 | $interpolation | string.swift:21:15:21:15 | &... |
+| string.swift:21:15:21:15 | : &... | string.swift:21:15:21:15 | WriteDef |
+| string.swift:21:15:21:15 | WriteDef | string.swift:21:18:21:18 | $interpolation |
+| string.swift:21:18:21:18 | $interpolation | string.swift:21:18:21:18 | &... |
+| string.swift:21:18:21:18 | : &... | string.swift:21:18:21:18 | WriteDef |
+| string.swift:21:18:21:18 | WriteDef | string.swift:21:13:21:13 | TapExpr |
+| string.swift:27:7:27:7 | WriteDef | string.swift:30:13:30:13 | clean |
+| string.swift:27:15:27:15 | abcdef | string.swift:27:7:27:7 | WriteDef |
+| string.swift:28:7:28:7 | WriteDef | string.swift:31:13:31:13 | tainted |
+| string.swift:28:17:28:25 | call to source2() | string.swift:28:7:28:7 | WriteDef |
+| string.swift:30:13:30:13 | clean | string.swift:33:13:33:13 | clean |
+| string.swift:31:13:31:13 | tainted | string.swift:34:21:34:21 | tainted |
+| string.swift:33:13:33:13 | clean | string.swift:33:21:33:21 | clean |
+| string.swift:33:21:33:21 | clean | string.swift:34:13:34:13 | clean |
+| string.swift:34:13:34:13 | clean | string.swift:35:23:35:23 | clean |
+| string.swift:34:21:34:21 | tainted | string.swift:35:13:35:13 | tainted |
+| string.swift:35:13:35:13 | tainted | string.swift:36:13:36:13 | tainted |
+| string.swift:35:23:35:23 | clean | string.swift:38:19:38:19 | clean |
+| string.swift:36:13:36:13 | tainted | string.swift:36:23:36:23 | tainted |
+| string.swift:36:23:36:23 | tainted | string.swift:39:19:39:19 | tainted |
+| string.swift:41:7:41:7 | WriteDef | string.swift:43:13:43:13 | str |
+| string.swift:41:13:41:13 | abc | string.swift:41:7:41:7 | WriteDef |
+| string.swift:43:13:43:13 | str | string.swift:45:3:45:3 | str |
+| string.swift:45:3:45:3 | : &... | string.swift:45:3:45:10 | WriteDef |
+| string.swift:45:3:45:3 | str | string.swift:45:3:45:3 | &... |
+| string.swift:45:3:45:10 | WriteDef | string.swift:46:13:46:13 | str |
+| string.swift:46:13:46:13 | str | string.swift:48:3:48:3 | str |
+| string.swift:48:3:48:3 | : &... | string.swift:48:3:48:18 | WriteDef |
+| string.swift:48:3:48:3 | str | string.swift:48:3:48:3 | &... |
+| string.swift:48:3:48:18 | WriteDef | string.swift:49:13:49:13 | str |
+| string.swift:51:7:51:7 | WriteDef | string.swift:53:13:53:13 | str2 |
+| string.swift:51:14:51:14 | abc | string.swift:51:7:51:7 | WriteDef |
+| string.swift:53:13:53:13 | str2 | string.swift:55:3:55:3 | str2 |
+| string.swift:55:3:55:3 | : &... | string.swift:55:3:55:8 | WriteDef |
+| string.swift:55:3:55:3 | str2 | string.swift:55:3:55:3 | &... |
+| string.swift:55:3:55:8 | WriteDef | string.swift:56:13:56:13 | str2 |
+| string.swift:56:13:56:13 | str2 | string.swift:58:3:58:3 | str2 |
+| string.swift:58:3:58:3 | : &... | string.swift:58:3:58:8 | WriteDef |
+| string.swift:58:3:58:3 | str2 | string.swift:58:3:58:3 | &... |
+| string.swift:58:3:58:8 | WriteDef | string.swift:59:13:59:13 | str2 |
+| string.swift:59:13:59:13 | str2 | string.swift:69:13:69:13 | str2 |
+| string.swift:61:7:61:7 | WriteDef | string.swift:63:13:63:13 | str3 |
+| string.swift:61:14:61:14 | abc | string.swift:61:7:61:7 | WriteDef |
+| string.swift:63:13:63:13 | str3 | string.swift:65:3:65:3 | str3 |
+| string.swift:65:3:65:3 | : &... | string.swift:65:3:65:8 | WriteDef |
+| string.swift:65:3:65:3 | str3 | string.swift:65:3:65:3 | &... |
+| string.swift:65:3:65:8 | WriteDef | string.swift:66:13:66:13 | str3 |
+| string.swift:66:13:66:13 | str3 | string.swift:68:3:68:3 | str3 |
+| string.swift:68:3:68:3 | str3 | string.swift:68:3:68:3 | &... |
+| string.swift:73:7:73:7 | WriteDef | string.swift:77:20:77:20 | clean |
+| string.swift:73:15:73:15 |  | string.swift:73:7:73:7 | WriteDef |
+| string.swift:74:7:74:7 | WriteDef | string.swift:78:20:78:20 | tainted |
+| string.swift:74:17:74:25 | call to source2() | string.swift:74:7:74:7 | WriteDef |
+| string.swift:75:7:75:7 | WriteDef | string.swift:79:20:79:20 | taintedInt |
+| string.swift:75:20:75:27 | call to source() | string.swift:75:7:75:7 | WriteDef |
+| string.swift:77:20:77:20 | clean | string.swift:81:31:81:31 | clean |
+| string.swift:78:20:78:20 | tainted | string.swift:82:31:82:31 | tainted |
+| string.swift:81:31:81:31 | clean | string.swift:84:13:84:13 | clean |
+| string.swift:82:31:82:31 | tainted | string.swift:85:13:85:13 | tainted |
+| string.swift:84:13:84:13 | clean | string.swift:87:13:87:13 | clean |
+| string.swift:85:13:85:13 | tainted | string.swift:88:13:88:13 | tainted |
+| try.swift:8:17:8:23 | call to clean() | try.swift:8:13:8:23 | try ... |
+| try.swift:9:17:9:24 | call to source() | try.swift:9:13:9:24 | try ... |
+| try.swift:14:17:14:23 | call to clean() | try.swift:14:12:14:23 | try! ... |
+| try.swift:15:17:15:24 | call to source() | try.swift:15:12:15:24 | try! ... |
+| try.swift:17:13:17:24 | try? ... | try.swift:17:12:17:26 | ...! |
+| try.swift:17:18:17:24 | call to clean() | try.swift:17:13:17:24 | try? ... |
+| try.swift:18:13:18:25 | try? ... | try.swift:18:12:18:27 | ...! |
+| try.swift:18:18:18:25 | call to source() | try.swift:18:13:18:25 | try? ... |
+| url.swift:12:6:12:6 | WriteDef | url.swift:14:29:14:29 | clean |
+| url.swift:12:14:12:14 | http://example.com/ | url.swift:12:6:12:6 | WriteDef |
+| url.swift:13:6:13:6 | WriteDef | url.swift:15:31:15:31 | tainted |
+| url.swift:13:16:13:23 | call to source() | url.swift:13:6:13:6 | WriteDef |
+| url.swift:14:6:14:6 | WriteDef | url.swift:17:12:17:12 | urlClean |
+| url.swift:14:17:14:34 | call to ... | url.swift:14:17:14:35 | ...! |
+| url.swift:14:17:14:35 | ...! | url.swift:14:6:14:6 | WriteDef |
+| url.swift:14:29:14:29 | clean | url.swift:20:24:20:24 | clean |
+| url.swift:15:6:15:6 | WriteDef | url.swift:18:12:18:12 | urlTainted |
+| url.swift:15:19:15:38 | call to ... | url.swift:15:19:15:39 | ...! |
+| url.swift:15:19:15:39 | ...! | url.swift:15:6:15:6 | WriteDef |
+| url.swift:15:31:15:31 | tainted | url.swift:21:24:21:24 | tainted |
+| url.swift:17:12:17:12 | urlClean | url.swift:22:43:22:43 | urlClean |
+| url.swift:18:12:18:12 | urlTainted | url.swift:23:43:23:43 | urlTainted |
+| url.swift:20:12:20:46 | call to ... | url.swift:20:12:20:47 | ...! |
+| url.swift:20:24:20:24 | clean | url.swift:22:24:22:24 | clean |
+| url.swift:21:12:21:48 | call to ... | url.swift:21:12:21:49 | ...! |
+| url.swift:21:24:21:24 | tainted | url.swift:29:25:29:25 | tainted |
+| url.swift:22:12:22:51 | call to ... | url.swift:22:12:22:52 | ...! |
+| url.swift:22:24:22:24 | clean | url.swift:23:24:23:24 | clean |
+| url.swift:23:12:23:53 | call to ... | url.swift:23:12:23:54 | ...! |
+| url.swift:23:24:23:24 | clean | url.swift:25:25:25:25 | clean |
+| url.swift:25:25:25:25 | clean | url.swift:34:26:34:26 | clean |
+| url.swift:29:25:29:25 | tainted | url.swift:38:28:38:28 | tainted |
+| url.swift:34:2:34:31 | WriteDef | url.swift:35:12:35:12 | urlClean2 |
+| url.swift:34:14:34:31 | call to ... | url.swift:34:2:34:31 | WriteDef |
+| url.swift:35:12:35:12 | urlClean2 | url.swift:35:12:35:12 | ...! |
+| url.swift:38:2:38:35 | WriteDef | url.swift:39:12:39:12 | urlTainted2 |
+| url.swift:38:16:38:35 | call to ... | url.swift:38:2:38:35 | WriteDef |
+| url.swift:39:12:39:12 | urlTainted2 | url.swift:39:12:39:12 | ...! |
diff --git a/swift/ql/test/library-tests/dataflow/taint/Taint.expected b/swift/ql/test/library-tests/dataflow/taint/Taint.expected
index fea536d78c05..dbfb89540bf2 100644
--- a/swift/ql/test/library-tests/dataflow/taint/Taint.expected
+++ b/swift/ql/test/library-tests/dataflow/taint/Taint.expected
@@ -1,20 +1,61 @@
 edges
-| test.swift:5:11:5:18 | call to source() :  | test.swift:7:13:7:13 | "..." |
-| test.swift:5:11:5:18 | call to source() :  | test.swift:9:13:9:13 | "..." |
-| test.swift:5:11:5:18 | call to source() :  | test.swift:11:13:11:13 | "..." |
-| test.swift:5:11:5:18 | call to source() :  | test.swift:16:13:16:13 | "..." |
-| test.swift:5:11:5:18 | call to source() :  | test.swift:18:13:18:13 | "..." |
+| string.swift:5:11:5:18 | call to source() :  | string.swift:7:13:7:13 | "..." |
+| string.swift:5:11:5:18 | call to source() :  | string.swift:9:13:9:13 | "..." |
+| string.swift:5:11:5:18 | call to source() :  | string.swift:11:13:11:13 | "..." |
+| string.swift:5:11:5:18 | call to source() :  | string.swift:16:13:16:13 | "..." |
+| string.swift:5:11:5:18 | call to source() :  | string.swift:18:13:18:13 | "..." |
+| string.swift:28:17:28:25 | call to source2() :  | string.swift:31:13:31:13 | tainted |
+| string.swift:28:17:28:25 | call to source2() :  | string.swift:34:13:34:21 | ... call to +(_:_:) ... |
+| string.swift:28:17:28:25 | call to source2() :  | string.swift:35:13:35:23 | ... call to +(_:_:) ... |
+| string.swift:28:17:28:25 | call to source2() :  | string.swift:36:13:36:23 | ... call to +(_:_:) ... |
+| string.swift:28:17:28:25 | call to source2() :  | string.swift:39:13:39:29 | ... call to +(_:_:) ... |
+| try.swift:9:17:9:24 | call to source() :  | try.swift:9:13:9:24 | try ... |
+| try.swift:15:17:15:24 | call to source() :  | try.swift:15:12:15:24 | try! ... |
+| try.swift:18:18:18:25 | call to source() :  | try.swift:18:12:18:27 | ...! |
+| url.swift:13:16:13:23 | call to source() :  | url.swift:18:12:18:12 | urlTainted |
+| url.swift:13:16:13:23 | call to source() :  | url.swift:21:12:21:49 | ...! |
+| url.swift:13:16:13:23 | call to source() :  | url.swift:23:12:23:54 | ...! |
+| url.swift:13:16:13:23 | call to source() :  | url.swift:39:12:39:12 | ...! |
 nodes
-| test.swift:5:11:5:18 | call to source() :  | semmle.label | call to source() :  |
-| test.swift:7:13:7:13 | "..." | semmle.label | "..." |
-| test.swift:9:13:9:13 | "..." | semmle.label | "..." |
-| test.swift:11:13:11:13 | "..." | semmle.label | "..." |
-| test.swift:16:13:16:13 | "..." | semmle.label | "..." |
-| test.swift:18:13:18:13 | "..." | semmle.label | "..." |
+| string.swift:5:11:5:18 | call to source() :  | semmle.label | call to source() :  |
+| string.swift:7:13:7:13 | "..." | semmle.label | "..." |
+| string.swift:9:13:9:13 | "..." | semmle.label | "..." |
+| string.swift:11:13:11:13 | "..." | semmle.label | "..." |
+| string.swift:16:13:16:13 | "..." | semmle.label | "..." |
+| string.swift:18:13:18:13 | "..." | semmle.label | "..." |
+| string.swift:28:17:28:25 | call to source2() :  | semmle.label | call to source2() :  |
+| string.swift:31:13:31:13 | tainted | semmle.label | tainted |
+| string.swift:34:13:34:21 | ... call to +(_:_:) ... | semmle.label | ... call to +(_:_:) ... |
+| string.swift:35:13:35:23 | ... call to +(_:_:) ... | semmle.label | ... call to +(_:_:) ... |
+| string.swift:36:13:36:23 | ... call to +(_:_:) ... | semmle.label | ... call to +(_:_:) ... |
+| string.swift:39:13:39:29 | ... call to +(_:_:) ... | semmle.label | ... call to +(_:_:) ... |
+| try.swift:9:13:9:24 | try ... | semmle.label | try ... |
+| try.swift:9:17:9:24 | call to source() :  | semmle.label | call to source() :  |
+| try.swift:15:12:15:24 | try! ... | semmle.label | try! ... |
+| try.swift:15:17:15:24 | call to source() :  | semmle.label | call to source() :  |
+| try.swift:18:12:18:27 | ...! | semmle.label | ...! |
+| try.swift:18:18:18:25 | call to source() :  | semmle.label | call to source() :  |
+| url.swift:13:16:13:23 | call to source() :  | semmle.label | call to source() :  |
+| url.swift:18:12:18:12 | urlTainted | semmle.label | urlTainted |
+| url.swift:21:12:21:49 | ...! | semmle.label | ...! |
+| url.swift:23:12:23:54 | ...! | semmle.label | ...! |
+| url.swift:39:12:39:12 | ...! | semmle.label | ...! |
 subpaths
 #select
-| test.swift:7:13:7:13 | "..." | test.swift:5:11:5:18 | call to source() :  | test.swift:7:13:7:13 | "..." | result |
-| test.swift:9:13:9:13 | "..." | test.swift:5:11:5:18 | call to source() :  | test.swift:9:13:9:13 | "..." | result |
-| test.swift:11:13:11:13 | "..." | test.swift:5:11:5:18 | call to source() :  | test.swift:11:13:11:13 | "..." | result |
-| test.swift:16:13:16:13 | "..." | test.swift:5:11:5:18 | call to source() :  | test.swift:16:13:16:13 | "..." | result |
-| test.swift:18:13:18:13 | "..." | test.swift:5:11:5:18 | call to source() :  | test.swift:18:13:18:13 | "..." | result |
+| string.swift:7:13:7:13 | "..." | string.swift:5:11:5:18 | call to source() :  | string.swift:7:13:7:13 | "..." | result |
+| string.swift:9:13:9:13 | "..." | string.swift:5:11:5:18 | call to source() :  | string.swift:9:13:9:13 | "..." | result |
+| string.swift:11:13:11:13 | "..." | string.swift:5:11:5:18 | call to source() :  | string.swift:11:13:11:13 | "..." | result |
+| string.swift:16:13:16:13 | "..." | string.swift:5:11:5:18 | call to source() :  | string.swift:16:13:16:13 | "..." | result |
+| string.swift:18:13:18:13 | "..." | string.swift:5:11:5:18 | call to source() :  | string.swift:18:13:18:13 | "..." | result |
+| string.swift:31:13:31:13 | tainted | string.swift:28:17:28:25 | call to source2() :  | string.swift:31:13:31:13 | tainted | result |
+| string.swift:34:13:34:21 | ... call to +(_:_:) ... | string.swift:28:17:28:25 | call to source2() :  | string.swift:34:13:34:21 | ... call to +(_:_:) ... | result |
+| string.swift:35:13:35:23 | ... call to +(_:_:) ... | string.swift:28:17:28:25 | call to source2() :  | string.swift:35:13:35:23 | ... call to +(_:_:) ... | result |
+| string.swift:36:13:36:23 | ... call to +(_:_:) ... | string.swift:28:17:28:25 | call to source2() :  | string.swift:36:13:36:23 | ... call to +(_:_:) ... | result |
+| string.swift:39:13:39:29 | ... call to +(_:_:) ... | string.swift:28:17:28:25 | call to source2() :  | string.swift:39:13:39:29 | ... call to +(_:_:) ... | result |
+| try.swift:9:13:9:24 | try ... | try.swift:9:17:9:24 | call to source() :  | try.swift:9:13:9:24 | try ... | result |
+| try.swift:15:12:15:24 | try! ... | try.swift:15:17:15:24 | call to source() :  | try.swift:15:12:15:24 | try! ... | result |
+| try.swift:18:12:18:27 | ...! | try.swift:18:18:18:25 | call to source() :  | try.swift:18:12:18:27 | ...! | result |
+| url.swift:18:12:18:12 | urlTainted | url.swift:13:16:13:23 | call to source() :  | url.swift:18:12:18:12 | urlTainted | result |
+| url.swift:21:12:21:49 | ...! | url.swift:13:16:13:23 | call to source() :  | url.swift:21:12:21:49 | ...! | result |
+| url.swift:23:12:23:54 | ...! | url.swift:13:16:13:23 | call to source() :  | url.swift:23:12:23:54 | ...! | result |
+| url.swift:39:12:39:12 | ...! | url.swift:13:16:13:23 | call to source() :  | url.swift:39:12:39:12 | ...! | result |
diff --git a/swift/ql/test/library-tests/dataflow/taint/Taint.ql b/swift/ql/test/library-tests/dataflow/taint/Taint.ql
index 35836c4cffcc..732976068886 100644
--- a/swift/ql/test/library-tests/dataflow/taint/Taint.ql
+++ b/swift/ql/test/library-tests/dataflow/taint/Taint.ql
@@ -11,12 +11,12 @@ class TestConfiguration extends TaintTracking::Configuration {
   TestConfiguration() { this = "TestConfiguration" }
 
   override predicate isSource(Node src) {
-    src.asExpr().(CallExpr).getStaticTarget().getName() = "source()"
+    src.asExpr().(CallExpr).getStaticTarget().getName().matches("source%")
   }
 
   override predicate isSink(Node sink) {
     exists(CallExpr sinkCall |
-      sinkCall.getStaticTarget().getName() = "sink(arg:)" and
+      sinkCall.getStaticTarget().getName().matches("sink%") and
       sinkCall.getAnArgument().getExpr() = sink.asExpr()
     )
   }
diff --git a/swift/ql/test/library-tests/dataflow/taint/data.swift b/swift/ql/test/library-tests/dataflow/taint/data.swift
new file mode 100644
index 000000000000..a1fddd129af1
--- /dev/null
+++ b/swift/ql/test/library-tests/dataflow/taint/data.swift
@@ -0,0 +1,25 @@
+
+class Data
+{
+    init<S>(_ elements: S) {}
+}
+
+func source() -> String { return "" }
+func sink(arg: Data) {}
+func sink2(arg: String) {}
+
+func taintThroughData() {
+	let dataClean = Data("123456".utf8)
+	let dataTainted = Data(source().utf8)
+	let dataTainted2 = Data(dataTainted)
+
+	sink(arg: dataClean)
+	sink(arg: dataTainted) // tainted [NOT DETECTED]
+	sink(arg: dataTainted2) // tainted [NOT DETECTED]
+
+	let stringClean = String(data: dataClean, encoding: String.Encoding.utf8)
+	let stringTainted = String(data: dataTainted, encoding: String.Encoding.utf8)
+
+	sink2(arg: stringClean!) // tainted [NOT DETECTED]
+	sink2(arg: stringTainted!) // tainted [NOT DETECTED]
+}
diff --git a/swift/ql/test/library-tests/dataflow/taint/string.swift b/swift/ql/test/library-tests/dataflow/taint/string.swift
new file mode 100644
index 000000000000..0855c6d91b04
--- /dev/null
+++ b/swift/ql/test/library-tests/dataflow/taint/string.swift
@@ -0,0 +1,89 @@
+func source() -> Int { return 0; }
+func sink(arg: String) {}
+
+func taintThroughInterpolatedStrings() {
+  var x = source()
+  
+  sink(arg: "\(x)") // tainted
+
+  sink(arg: "\(x) \(x)") // tainted
+
+  sink(arg: "\(x) \(0) \(x)") // tainted
+
+  var y = 42
+  sink(arg: "\(y)") // clean
+
+  sink(arg: "\(x) hello \(y)") // tainted
+
+  sink(arg: "\(y) world \(x)") // tainted
+
+  x = 0
+  sink(arg: "\(x)") // clean
+}
+
+func source2() -> String { return ""; }
+
+func taintThroughStringConcatenation() {
+  var clean = "abcdef"
+  var tainted = source2()
+
+  sink(arg: clean)
+  sink(arg: tainted) // tainted
+
+  sink(arg: clean + clean)
+  sink(arg: clean + tainted) // tainted
+  sink(arg: tainted + clean) // tainted
+  sink(arg: tainted + tainted) // tainted
+
+  sink(arg: ">" + clean + "<")
+  sink(arg: ">" + tainted + "<") // tainted
+
+  var str = "abc"
+
+  sink(arg: str)
+
+  str += "def"
+  sink(arg: str)
+
+  str += source2()
+  sink(arg: str) // tainted [NOT DETECTED]
+
+  var str2 = "abc"
+
+  sink(arg: str2)
+
+  str2.append("def")
+  sink(arg: str2)
+
+  str2.append(source2())
+  sink(arg: str2) // tainted [NOT DETECTED]
+
+  var str3 = "abc"
+
+  sink(arg: str3)
+
+  str3.append(contentsOf: "def")
+  sink(arg: str3)
+
+  str3.append(contentsOf: source2())
+  sink(arg: str2) // tainted [NOT DETECTED]
+}
+
+func taintThroughStringOperations() {
+  var clean = ""
+  var tainted = source2()
+  var taintedInt = source()
+
+  sink(arg: String(clean))
+  sink(arg: String(tainted)) // tainted [NOT DETECTED]
+  sink(arg: String(taintedInt)) // tainted [NOT DETECTED]
+
+  sink(arg: String(repeating: clean, count: 2))
+  sink(arg: String(repeating: tainted, count: 2)) // tainted [NOT DETECTED]
+
+  sink(arg: clean.description)
+  sink(arg: tainted.description) // tainted [NOT DETECTED]
+  
+  sink(arg: clean.debugDescription)
+  sink(arg: tainted.debugDescription) // tainted [NOT DETECTED]
+}
diff --git a/swift/ql/test/library-tests/dataflow/taint/test.swift b/swift/ql/test/library-tests/dataflow/taint/test.swift
deleted file mode 100644
index 36ff201788be..000000000000
--- a/swift/ql/test/library-tests/dataflow/taint/test.swift
+++ /dev/null
@@ -1,22 +0,0 @@
-func source() -> Int { return 0; }
-func sink(arg: String) {}
-
-func taintThroughInterpolatedStrings() {
-  var x = source()
-  
-  sink(arg: "\(x)") // tainted
-
-  sink(arg: "\(x) \(x)") // tainted
-
-  sink(arg: "\(x) \(0) \(x)") // tainted
-
-  var y = 42
-  sink(arg: "\(y)") // clean
-
-  sink(arg: "\(x) hello \(y)") // tainted
-
-  sink(arg: "\(y) world \(x)") // tainted
-
-  x = 0
-  sink(arg: "\(x)") // clean
-}
\ No newline at end of file
diff --git a/swift/ql/test/library-tests/dataflow/taint/try.swift b/swift/ql/test/library-tests/dataflow/taint/try.swift
new file mode 100644
index 000000000000..80c0bbc07a65
--- /dev/null
+++ b/swift/ql/test/library-tests/dataflow/taint/try.swift
@@ -0,0 +1,19 @@
+func clean() throws -> String { return ""; }
+func source() throws -> String { return ""; }
+func sink(arg: String) {}
+
+func taintThroughTry() {
+	do
+	{
+		sink(arg: try clean())
+		sink(arg: try source()) // tainted
+	} catch {
+		// ...
+	}
+
+	sink(arg: try! clean())
+	sink(arg: try! source()) // tainted
+
+	sink(arg: (try? clean())!)
+	sink(arg: (try? source())!) // tainted
+}
diff --git a/swift/ql/test/library-tests/dataflow/taint/url.swift b/swift/ql/test/library-tests/dataflow/taint/url.swift
new file mode 100644
index 000000000000..c7cb5ab12dba
--- /dev/null
+++ b/swift/ql/test/library-tests/dataflow/taint/url.swift
@@ -0,0 +1,40 @@
+
+class URL
+{
+	init?(string: String) {}
+	init?(string: String, relativeTo: URL?) {}
+}
+
+func source() -> String { return "" }
+func sink(arg: URL) {}
+
+func taintThroughURL() {
+	let clean = "http://example.com/"
+	let tainted = source()
+	let urlClean = URL(string: clean)!
+	let urlTainted = URL(string: tainted)!
+
+	sink(arg: urlClean)
+	sink(arg: urlTainted) // tainted
+
+	sink(arg: URL(string: clean, relativeTo: nil)!)
+	sink(arg: URL(string: tainted, relativeTo: nil)!) // tainted
+	sink(arg: URL(string: clean, relativeTo: urlClean)!)
+	sink(arg: URL(string: clean, relativeTo: urlTainted)!) // tainted
+
+	if let x = URL(string: clean) {
+		sink(arg: x)
+	}
+
+	if let y = URL(string: tainted) {
+		sink(arg: y) // tainted [NOT DETECTED]
+	}
+
+	var urlClean2 : URL!
+	urlClean2 = URL(string: clean)
+	sink(arg: urlClean2)
+
+	var urlTainted2 : URL!
+	urlTainted2 = URL(string: tainted)
+	sink(arg: urlTainted2) // tainted
+}