wip12

Author: hvitved

rust/ql/lib/codeql/rust/internal/typeinference/TypeInference.qll

@@ -450,11 +450,9 @@ private module Input3 implements InputSig3 {
   }
 
   bindingset[derefChainBorrow]
-  Type inferCallArgumentType(Call call, string derefChainBorrow, int i, TypePath path) {
-    exists(FunctionPosition pos |
-      i = pos.asPosition() and
-      result = call.(FunctionCallMatchingInput::Access).getInferredType(derefChainBorrow, pos, path)
-    )
+  Type inferCallArgumentType(Call call, string derefChainBorrow, int pos, TypePath path) {
+    result =
+      call.(FunctionCallMatchingInput::Access).getInferredArgumentType(derefChainBorrow, pos, path)
   }
 
   Type inferCallArgumentType(AstNode n, TypePath path) {
@@ -1039,9 +1037,6 @@ private class NonAssocCallExpr extends CallExpr {
 
   pragma[nomagic]
   Type getInferredType(FunctionPosition pos, TypePath path) {
-    pos.isTypeQualifier() and
-    result = getCallExprTypeQualifier(this, path, false)
-    or
     result = inferType(this.getNodeAt(pos), path)
   }
 }
@@ -2587,7 +2582,7 @@ private module AssocFunctionResolution {
  * A matching configuration for resolving types of function call expressions
  * like `foo.bar(baz)` and `Foo::bar(baz)`.
  */
-private module FunctionCallMatchingInput implements MatchingWithEnvironmentInputSig {
+private module FunctionCallMatchingInput {
   import FunctionPositionMatchingInput
 
   private newtype TDeclaration =
@@ -2681,9 +2676,7 @@ private module FunctionCallMatchingInput implements MatchingWithEnvironmentInput
   }
 
   bindingset[derefChainBorrow]
-  additional predicate decodeDerefChainBorrow(
-    string derefChainBorrow, DerefChain derefChain, BorrowKind borrow
-  ) {
+  predicate decodeDerefChainBorrow(string derefChainBorrow, DerefChain derefChain, BorrowKind borrow) {
     exists(int i |
       i = derefChainBorrow.indexOf(";") and
       derefChain = derefChainBorrow.prefix(i) and
@@ -2704,8 +2697,10 @@ private module FunctionCallMatchingInput implements MatchingWithEnvironmentInput
   abstract private class AccessImpl extends ContextTyping::ContextTypedCallCand {
     abstract AstNode getNodeAt(FunctionPosition pos);
 
+    // bindingset[derefChainBorrow]
+    // abstract Type getInferredType(string derefChainBorrow, FunctionPosition pos, TypePath path);
     bindingset[derefChainBorrow]
-    abstract Type getInferredType(string derefChainBorrow, FunctionPosition pos, TypePath path);
+    abstract Type getInferredArgumentType(string derefChainBorrow, int pos, TypePath path);
 
     abstract Declaration getTarget(string derefChainBorrow);
 
@@ -2740,22 +2735,26 @@ private module FunctionCallMatchingInput implements MatchingWithEnvironmentInput
     }
 
     pragma[nomagic]
-    private Type getInferredSelfType(FunctionPosition pos, string derefChainBorrow, TypePath path) {
-      exists(DerefChain derefChain, BorrowKind borrow |
-        result = super.getSelfTypeAt(pos, derefChain, borrow, path) and
+    private Type getInferredSelfType(int pos, string derefChainBorrow, TypePath path) {
+      exists(FunctionPosition fpos, DerefChain derefChain, BorrowKind borrow |
+        result = super.getSelfTypeAt(fpos, derefChain, borrow, path) and
         derefChainBorrow = encodeDerefChainBorrow(derefChain, borrow) and
-        super.hasReceiverAtPos(pos)
+        super.hasReceiverAtPos(fpos) and
+        pos = fpos.asPosition()
       )
     }
 
     pragma[nomagic]
-    private Type getInferredNonSelfType(FunctionPosition pos, TypePath path) {
-      not super.hasReceiverAtPos(pos) and
-      result = super.getTypeAt(pos, path)
+    private Type getInferredNonSelfType(int pos, TypePath path) {
+      exists(FunctionPosition fpos |
+        not super.hasReceiverAtPos(fpos) and
+        result = super.getTypeAt(fpos, path) and
+        pos = fpos.asPosition()
+      )
     }
 
     bindingset[derefChainBorrow]
-    override Type getInferredType(string derefChainBorrow, FunctionPosition pos, TypePath path) {
+    override Type getInferredArgumentType(string derefChainBorrow, int pos, TypePath path) {
       result = this.getInferredSelfType(pos, derefChainBorrow, path)
       or
       result = this.getInferredNonSelfType(pos, path)
@@ -2811,14 +2810,17 @@ private module FunctionCallMatchingInput implements MatchingWithEnvironmentInput
     }
 
     pragma[nomagic]
-    private Type getInferredType(FunctionPosition pos, TypePath path) {
-      result = super.getInferredType(pos, path)
+    private Type getInferredArgumentType(int pos, TypePath path) {
+      exists(FunctionPosition fpos |
+        result = super.getInferredType(fpos, path) and
+        pos = fpos.asPosition()
+      )
     }
 
     bindingset[derefChainBorrow]
-    override Type getInferredType(string derefChainBorrow, FunctionPosition pos, TypePath path) {
+    override Type getInferredArgumentType(string derefChainBorrow, int pos, TypePath path) {
       exists(derefChainBorrow) and
-      result = this.getInferredType(pos, path)
+      result = this.getInferredArgumentType(pos, path)
     }
 
     pragma[nomagic]

shared/typeinference/codeql/typeinference/internal/TypeInference.qll

@@ -2219,7 +2219,7 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
          * Gets the declared type of the `i`th parameter of this callable at `path`.
          *
          * This should also include (possibly implicit) `this`/`self` parameters,
-         * using index `-1`.
+         * using index `0`.
          */
         Type getParameterType(int i, TypePath path);
 
@@ -2241,7 +2241,7 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
         /**
          * Gets the AST node corresponding to the `i`th argument of this call.
          *
-         * This should include the receiver argument for method calls, using index `-1`.
+         * This should include the receiver argument for method calls, using index `0`.
          */
         AstNode getArgument(int i);
 
@@ -2483,7 +2483,7 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
       private predicate hasUnknownType(AstNode n) { hasUnknownTypeAt(n, _) }
 
       pragma[nomagic]
-      private Type inferTypeTopDownCand(AstNode n, TypePath path) {
+      private Type inferTypeContextualCand(AstNode n, TypePath path) {
         result = inferTypeTopDown(n, path)
         or
         result = inferCallArgumentType(n, path)
@@ -2496,8 +2496,8 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
       }
 
       pragma[nomagic]
-      private Type inferTypeTopDownCand(AstNode n, TypePath prefix, TypePath path) {
-        result = inferTypeTopDownCand(n, path) and
+      private Type inferTypeContextualCand(AstNode n, TypePath prefix, TypePath path) {
+        result = inferTypeContextualCand(n, path) and
         hasUnknownType(n) and
         prefix = path.getAPrefix()
       }
@@ -2518,9 +2518,10 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
         or
         result = inferCallReturnType(n, _, path)
         or
-        // top-down inference
+        // contextual typing: only propagate type information from surrounding context
+        // into a node which has an explicitly unknown type
         exists(TypePath prefix |
-          result = inferTypeTopDownCand(n, prefix, path) and
+          result = inferTypeContextualCand(n, prefix, path) and
           hasUnknownTypeAt(n, prefix)
         )
       }
@@ -2581,13 +2582,16 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
           apos = dpos
         }
 
+        /** Gets the position used to represent the return type of a callable/type of a call. */
+        additional int getReturnPosition() { result = -1 }
+
         final private class CallableFinal = Callable;
 
         class Declaration extends CallableFinal {
           Type getDeclaredType(DeclarationPosition dpos, TypePath path) {
             result = this.getParameterType(dpos, path)
             or
-            dpos = -2 and
+            dpos = getReturnPosition() and
             result = this.getReturnType(path)
           }
         }
@@ -2605,14 +2609,18 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
         final private class CallFinal = Call;
 
         class Access extends CallFinal {
+          pragma[nomagic]
+          private Type getInferredResultType(AccessPosition apos, TypePath path) {
+            result = inferType(this, path) and
+            apos = getReturnPosition()
+          }
+
           bindingset[e]
           Type getInferredType(AccessEnvironment e, AccessPosition apos, TypePath path) {
             result = inferCallArgumentType(this, e, apos, path)
             or
-            result = inferType(this, path) and
-            exists(e) and
-            apos = -2
-            // todo: adjust return type
+            result = this.getInferredResultType(apos, path) and
+            exists(e)
           }
 
           Declaration getTarget(AccessEnvironment e) { result = super.getTarget(e) }
@@ -2621,8 +2629,10 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
 
       private module CallMatching = MatchingWithEnvironment<CallMatchingInput>;
 
+      pragma[nomagic]
       private Type inferCallReturnType(Call call, CallResolutionContext ctx, TypePath path) {
-        result = CallMatching::inferAccessType(call, ctx, -2, path)
+        result =
+          CallMatching::inferAccessType(call, ctx, CallMatchingInput::getReturnPosition(), path)
       }
 
       Type inferCallArgumentType(