Swift: extract AppliedPropertyWrapperExpr

Author: redsun82

swift/extractor/translators/ExprTranslator.cpp

@@ -573,4 +573,25 @@ ExprTranslator::translatePropertyWrapperValuePlaceholderExpr(
   return entry;
 }
 
+static int translatePropertyWrapperValueKind(swift::AppliedPropertyWrapperExpr::ValueKind kind) {
+  using K = swift::AppliedPropertyWrapperExpr::ValueKind;
+  switch (kind) {
+    case K::WrappedValue:
+      return 1;
+    case K::ProjectedValue:
+      return 2;
+    default:
+      return 0;
+  }
+}
+codeql::AppliedPropertyWrapperExpr ExprTranslator::translateAppliedPropertyWrapperExpr(
+    const swift::AppliedPropertyWrapperExpr& expr) {
+  auto entry = createExprEntry(expr);
+  entry.kind = translatePropertyWrapperValueKind(expr.getValueKind());
+  entry.value =
+      dispatcher.fetchLabel(const_cast<swift::AppliedPropertyWrapperExpr&>(expr).getValue());
+  entry.param = dispatcher.fetchLabel(expr.getParamDecl());
+  return entry;
+}
+
 }  // namespace codeql

swift/extractor/translators/ExprTranslator.h

@@ -113,6 +113,8 @@ class ExprTranslator : public AstTranslatorBase<ExprTranslator> {
       const swift::UnresolvedSpecializeExpr& expr);
   codeql::PropertyWrapperValuePlaceholderExpr translatePropertyWrapperValuePlaceholderExpr(
       const swift::PropertyWrapperValuePlaceholderExpr& expr);
+  codeql::AppliedPropertyWrapperExpr translateAppliedPropertyWrapperExpr(
+      const swift::AppliedPropertyWrapperExpr& expr);
 
  private:
   void fillAbstractClosureExpr(const swift::AbstractClosureExpr& expr,

swift/ql/lib/codeql/swift/generated/ParentChild.qll

@@ -962,14 +962,17 @@ private module Impl {
   private Element getImmediateChildOfAppliedPropertyWrapperExpr(
     AppliedPropertyWrapperExpr e, int index, string partialPredicateCall
   ) {
-    exists(int b, int bExpr, int n |
+    exists(int b, int bExpr, int n, int nValue |
       b = 0 and
       bExpr = b + 1 + max(int i | i = -1 or exists(getImmediateChildOfExpr(e, i, _)) | i) and
       n = bExpr and
+      nValue = n + 1 and
       (
         none()
         or
         result = getImmediateChildOfExpr(e, index - b, partialPredicateCall)
+        or
+        index = n and result = e.getImmediateValue() and partialPredicateCall = "Value()"
       )
     )
   }

swift/ql/lib/codeql/swift/generated/Raw.qll

@@ -327,6 +327,12 @@ module Raw {
 
   class AppliedPropertyWrapperExpr extends @applied_property_wrapper_expr, Expr {
     override string toString() { result = "AppliedPropertyWrapperExpr" }
+
+    int getKind() { applied_property_wrapper_exprs(this, result, _, _) }
+
+    Expr getValue() { applied_property_wrapper_exprs(this, _, result, _) }
+
+    ParamDecl getParam() { applied_property_wrapper_exprs(this, _, _, result) }
   }
 
   class ApplyExpr extends @apply_expr, Expr {

swift/ql/lib/codeql/swift/generated/expr/AppliedPropertyWrapperExpr.qll

@@ -2,9 +2,63 @@
 private import codeql.swift.generated.Synth
 private import codeql.swift.generated.Raw
 import codeql.swift.elements.expr.Expr
+import codeql.swift.elements.decl.ParamDecl
 
 module Generated {
+  /**
+   * An implicit application of a property wrapper.
+   */
   class AppliedPropertyWrapperExpr extends Synth::TAppliedPropertyWrapperExpr, Expr {
     override string getAPrimaryQlClass() { result = "AppliedPropertyWrapperExpr" }
+
+    /**
+     * Gets the kind of this applied property wrapper expression.
+     *
+     * This is 1 for the wrapped value and 2 for the projected one.
+     */
+    int getKind() {
+      result =
+        Synth::convertAppliedPropertyWrapperExprToRaw(this)
+            .(Raw::AppliedPropertyWrapperExpr)
+            .getKind()
+    }
+
+    /**
+     * Gets the value of this applied property wrapper expression.
+     *
+     * This includes nodes from the "hidden" AST. It can be overridden in subclasses to change the
+     * behavior of both the `Immediate` and non-`Immediate` versions.
+     */
+    Expr getImmediateValue() {
+      result =
+        Synth::convertExprFromRaw(Synth::convertAppliedPropertyWrapperExprToRaw(this)
+              .(Raw::AppliedPropertyWrapperExpr)
+              .getValue())
+    }
+
+    /**
+     * Gets the value of this applied property wrapper expression.
+     *
+     * The value on which the wrapper is applied.
+     */
+    final Expr getValue() { result = getImmediateValue().resolve() }
+
+    /**
+     * Gets the parameter declaration owning this wrapper application.
+     *
+     * This includes nodes from the "hidden" AST. It can be overridden in subclasses to change the
+     * behavior of both the `Immediate` and non-`Immediate` versions.
+     */
+    ParamDecl getImmediateParam() {
+      result =
+        Synth::convertParamDeclFromRaw(Synth::convertAppliedPropertyWrapperExprToRaw(this)
+              .(Raw::AppliedPropertyWrapperExpr)
+              .getParam())
+    }
+
+    /**
+     * Gets the parameter declaration owning this wrapper application.
+     */
+    final ParamDecl getParam() { result = getImmediateParam().resolve() }
   }
 }

swift/ql/lib/swift.dbscheme

@@ -664,7 +664,10 @@ any_try_exprs(  //dir=expr
 );
 
 applied_property_wrapper_exprs(  //dir=expr
-  unique int id: @applied_property_wrapper_expr
+  unique int id: @applied_property_wrapper_expr,
+  int kind: int ref,
+  int value: @expr_or_none ref,
+  int param: @param_decl_or_none ref
 );
 
 @apply_expr =

swift/ql/test/TestUtils.qll

@@ -4,6 +4,8 @@ cached
 predicate toBeTested(Element e) {
   e instanceof File
   or
+  e instanceof AppliedPropertyWrapperExpr
+  or
   exists(ModuleDecl m |
     m = e and
     not m.isBuiltinModule() and

swift/ql/test/extractor-tests/generated/expr/AppliedPropertyWrapperExpr/AppliedPropertyWrapperExpr.expected

@@ -0,0 +1,3 @@
+| applied_property_wrapper.swift:14:8:14:8 | AppliedPropertyWrapperExpr | getKind: | 1 | getValue: | applied_property_wrapper.swift:14:8:14:8 | 42 | getParam: | applied_property_wrapper.swift:12:19:12:22 | x |
+| applied_property_wrapper.swift:15:9:15:9 | AppliedPropertyWrapperExpr | getKind: | 2 | getValue: | applied_property_wrapper.swift:15:9:15:9 | true | getParam: | applied_property_wrapper.swift:12:19:12:22 | x |
+| file://:0:0:0:0 | AppliedPropertyWrapperExpr | getKind: | 1 | getValue: | file://:0:0:0:0 | y | getParam: | applied_property_wrapper.swift:17:26:17:29 | y |

swift/ql/test/extractor-tests/generated/expr/AppliedPropertyWrapperExpr/AppliedPropertyWrapperExpr.ql

@@ -0,0 +1,12 @@
+// generated by codegen/codegen.py
+import codeql.swift.elements
+import TestUtils
+
+from AppliedPropertyWrapperExpr x, int getKind, Expr getValue, ParamDecl getParam
+where
+  toBeTested(x) and
+  not x.isUnknown() and
+  getKind = x.getKind() and
+  getValue = x.getValue() and
+  getParam = x.getParam()
+select x, "getKind:", getKind, "getValue:", getValue, "getParam:", getParam