wip3

Author: hvitved

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

@@ -1033,7 +1033,7 @@ private class FunctionDeclaration extends Function {
     result = [this.getGenericParamList().getATypeParam(), i.asSome().getTypeParam(_)]
   }
 
-  TypeParameter getTypeParameter(ImplOrTraitItemNodeOption i, TypeParameterPosition ppos) {
+  private TypeParameter getTypeParameter(ImplOrTraitItemNodeOption i, TypeParameterPosition ppos) {
     result = ppos.asTypeParameter() and
     (
       result = TTypeParamTypeParameter(this.getTypeParam(i))
@@ -1053,45 +1053,22 @@ private class FunctionDeclaration extends Function {
     )
   }
 
-  pragma[nomagic]
-  Type getParameterType(ImplOrTraitItemNodeOption i, int pos, TypePath path) {
-    i = parent and
-    exists(FunctionPosition fpos | pos = fpos.asPosition() |
-      // exists(i.asSome()) and
-      result = getAssocFunctionTypeAt(this, i.asSome(), fpos, path)
+  TypeParameter getTypeParameter(TypeParameterPosition ppos) {
+    exists(ImplOrTraitItemNodeOption i | result = this.getTypeParameter(i, ppos) |
+      i.isNone()
       or
-      // result = fpos.getTypeMention(this).getTypeAt(path)
-      i.isNone() and
-      result = this.getParam(pos).getTypeRepr().(TypeMention).getTypeAt(path)
+      i.asSome().getAnAssocItem() = this
     )
   }
 
-  private Type resolveRetType(ImplOrTraitItemNodeOption i, TypePath path) {
-    i = parent and
-    (
-      result =
-        getAssocFunctionTypeAt(this, i.asSome(), any(FunctionPosition ret | ret.isReturn()), path)
-      or
-      i.isNone() and
-      result = getReturnTypeMention(this).getTypeAt(path)
+  pragma[nomagic]
+  Type getParameterType(int j, TypePath path) {
+    exists(FunctionPosition fpos | j = fpos.asPosition() |
+      result = fpos.getTypeMention(this).getTypeAt(path)
     )
   }
 
-  Type getReturnType(ImplOrTraitItemNodeOption i, TypePath path) {
-    if this.isAsync()
-    then
-      i = parent and
-      path.isEmpty() and
-      result = getFutureTraitType()
-      or
-      exists(TypePath suffix |
-        result = this.resolveRetType(i, suffix) and
-        path = TypePath::cons(getDynFutureOutputTypeParameter(), suffix)
-      )
-    else result = this.resolveRetType(i, path)
-  }
-
-  Type getReturnType2(TypePath path) {
+  Type getReturnType(TypePath path) {
     if this.isAsync()
     then
       path.isEmpty() and
@@ -1103,14 +1080,6 @@ private class FunctionDeclaration extends Function {
       )
     else result = getReturnTypeMention(this).getTypeAt(path)
   }
-
-  string toStringExt(ImplOrTraitItemNode i) {
-    i = parent.asSome() and
-    if this = i.getAnAssocItem()
-    then result = this.toString()
-    else
-      result = this + " [" + [i.(Impl).getSelfTy().toString(), i.(Trait).getName().toString()] + "]"
-  }
 }
 
 private class AssocFunctionDeclaration extends FunctionDeclaration {
@@ -1316,16 +1285,12 @@ private module ContextualTyping {
    */
   pragma[nomagic]
   private predicate assocFunctionMentionsTypeParameterAtNonRetPos(
-    ImplOrTraitItemNode i, Function f, TypeParameter tp
+    FunctionDeclaration f, TypeParameter tp
   ) {
-    exists(FunctionPosition nonRetPos |
-      not nonRetPos.isReturn() and
-      not nonRetPos.isTypeQualifier() and
-      tp = getAssocFunctionTypeAt(f, i, nonRetPos, _)
-    )
+    tp = f.getParameterType(_, _)
     or
     exists(TypeParameter mid |
-      assocFunctionMentionsTypeParameterAtNonRetPos(i, f, mid) and
+      assocFunctionMentionsTypeParameterAtNonRetPos(f, mid) and
       tp = getATypeParameterConstraint(mid).getTypeAt(_)
     )
   }
@@ -1342,11 +1307,10 @@ private module ContextualTyping {
    */
   pragma[nomagic]
   private predicate assocFunctionReturnContextTypedAt(
-    ImplOrTraitItemNode i, Function f, FunctionPosition pos, TypePath path, TypeParameter tp
+    FunctionDeclaration f, TypePath path, TypeParameter tp
   ) {
-    pos.isReturn() and
-    tp = getAssocFunctionTypeAt(f, i, pos, path) and
-    not assocFunctionMentionsTypeParameterAtNonRetPos(i, f, tp)
+    tp = f.getReturnType(path) and
+    not assocFunctionMentionsTypeParameterAtNonRetPos(f, tp)
   }
 
   /**
@@ -1362,16 +1326,14 @@ private module ContextualTyping {
     }
 
     /**
-     * Holds if this call resolves to `target` inside `i`, and the return type
-     * at `pos` and `path` may have to be inferred from the context.
+     * Holds if this call resolves to `target`, and the return type at `pos` and
+     * `path` may have to be inferred from the context.
      */
-    bindingset[this, i, target]
-    predicate hasUnknownTypeAt(
-      ImplOrTraitItemNode i, FunctionDeclaration target, FunctionPosition pos, TypePath path
-    ) {
+    bindingset[this, target]
+    predicate hasUnknownTypeAt0(FunctionDeclaration target, TypePath path) {
       exists(TypeParameter tp, TypeParameterPosition tppos |
-        assocFunctionReturnContextTypedAt(i, target, pos, path, tp) and
-        tp = target.getTypeParameter(ImplOrTraitItemNodeOption::some(i), tppos) and
+        assocFunctionReturnContextTypedAt(target, path, tp) and
+        tp = target.getTypeParameter(tppos) and
         // check that no explicit type arguments have been supplied for `tp`
         not exists(TypeArgumentPosition tapos |
           this.hasTypeArgument(tapos) and
@@ -2850,23 +2812,7 @@ private module AssocFunctionResolution {
  * like `foo.bar(baz)` and `Foo::bar(baz)`.
  */
 private module FunctionCallMatchingInput {
-  final class Declaration extends FunctionDeclaration {
-    TypeParameter getTypeParameter(TypeParameterPosition ppos) {
-      exists(ImplOrTraitItemNodeOption i | result = this.getTypeParameter(i, ppos) |
-        i.isNone()
-        or
-        i.asSome().getAnAssocItem() = this
-      )
-    }
-
-    Type getParameterType(int j, TypePath path) {
-      exists(FunctionPosition fpos | j = fpos.asPosition() |
-        result = fpos.getTypeMention(this).getTypeAt(path)
-      )
-    }
-
-    Type getReturnType(TypePath path) { result = this.getReturnType2(path) }
-  }
+  class Declaration = FunctionDeclaration;
 
   pragma[nomagic]
   private TypeMention getAdditionalTypeParameterConstraint(TypeParameter tp, Declaration decl) {
@@ -2920,7 +2866,7 @@ private module FunctionCallMatchingInput {
      * Holds if the return type of this call at `path` may have to be inferred
      * from the context.
      */
-    abstract predicate hasUnknownTypeAt(string derefChainBorrow, FunctionPosition pos, TypePath path);
+    abstract predicate hasUnknownTypeAt(string derefChainBorrow, TypePath path);
   }
 
   private class AssocFunctionCallAccess extends AccessImpl instanceof AssocFunctionResolution::AssocFunctionCall
@@ -2984,23 +2930,17 @@ private module FunctionCallMatchingInput {
     }
 
     pragma[nomagic]
-    override predicate hasUnknownTypeAt(string derefChainBorrow, FunctionPosition pos, TypePath path) {
-      exists(ImplOrTraitItemNode i |
-        this.hasUnknownTypeAt(i, this.getTarget(i, derefChainBorrow), pos, path)
-      )
+    override predicate hasUnknownTypeAt(string derefChainBorrow, TypePath path) {
+      this.hasUnknownTypeAt0(this.getTarget(_, derefChainBorrow), path)
       or
       derefChainBorrow = noDerefChainBorrow() and
-      forex(ImplOrTraitItemNode i, Function f |
-        f = CallExprImpl::getResolvedFunction(this) and
-        f = i.getAnAssocItem()
-      |
-        this.hasUnknownTypeAt(i, f, pos, path)
+      forex(Function f | f = CallExprImpl::getResolvedFunction(this) |
+        this.hasUnknownTypeAt0(f, path)
       )
       or
       exists(DerefChain derefChain, BorrowKind borrow |
         super.resolutionDependsOnReturnType(derefChain, borrow) and
         derefChainBorrow = encodeDerefChainBorrow(derefChain, borrow) and
-        pos.isReturn() and
         path.isEmpty()
       )
     }
@@ -3041,13 +2981,12 @@ private module FunctionCallMatchingInput {
     }
 
     pragma[nomagic]
-    override predicate hasUnknownTypeAt(string derefChainBorrow, FunctionPosition pos, TypePath path) {
+    override predicate hasUnknownTypeAt(string derefChainBorrow, TypePath path) {
       derefChainBorrow = noDerefChainBorrow() and
       exists(FunctionDeclaration f, TypeParameter tp |
         f = super.resolveCallTargetViaPathResolution() and
-        pos.isReturn() and
-        tp = f.getReturnType(_, path) and
-        not tp = f.getParameterType(_, _, _) and
+        tp = f.getReturnType(path) and
+        not tp = f.getParameterType(_, _) and
         // check that no explicit type arguments have been supplied for `tp`
         not exists(TypeArgumentPosition tapos |
           this.hasTypeArgument(tapos) and
@@ -3120,10 +3059,7 @@ pragma[nomagic]
 private Type inferUnknownType(AstNode n, TypePath path) {
   result = TUnknownType() and
   (
-    exists(FunctionCallMatchingInput::Access call, FunctionPosition pos |
-      n = call.getNodeAt(pos) and
-      call.hasUnknownTypeAt(_, pos, path)
-    )
+    n.(FunctionCallMatchingInput::Access).hasUnknownTypeAt(_, path)
     or
     n.(Input3::Construction).hasUnknownReturnTypeAt(path)
     or

rust/ql/test/library-tests/type-inference/type-inference.expected

@@ -7787,7 +7787,6 @@ inferType
 | main.rs:764:17:764:26 | ...::m2(...) |  | {EXTERNAL LOCATION} | i32 |
 | main.rs:764:24:764:25 | S1 |  | main.rs:606:5:607:14 | S1 |
 | main.rs:765:13:765:13 | y |  | {EXTERNAL LOCATION} | i32 |
-| main.rs:765:22:765:31 | ...::m2(...) |  | {EXTERNAL LOCATION} | i32 |
 | main.rs:765:29:765:30 | S2 |  | main.rs:608:5:609:14 | S2 |
 | main.rs:782:15:782:18 | SelfParam |  | main.rs:770:5:774:5 | MyEnum |
 | main.rs:782:15:782:18 | SelfParam | A | main.rs:781:10:781:10 | T |