wip

Author: hvitved

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

@@ -232,25 +232,14 @@ private module Input3 implements InputSig3 {
     (exists(resolveTupleFieldExpr(_, _)) implies any())
   }
 
+  predicate inferTypeForDefaults = M3::inferType/2;
+
   class BoolType extends DataType {
     BoolType() { this.getTypeItem() instanceof Builtins::Bool }
   }
 
   class AstNode = Rust::AstNode;
 
-  // todo: remove
-  TypeMention getTypeAnnotation(AstNode n) {
-    exists(Static static |
-      n = static and
-      result = static.getTypeRepr()
-    )
-    or
-    exists(Const c |
-      n = c and
-      result = c.getTypeRepr()
-    )
-  }
-
   class Expr = Rust::Expr;
 
   class Cast extends CastExpr {
@@ -978,6 +967,18 @@ private module Input3 implements InputSig3 {
     result instanceof UnitType
     or
     result = inferClosureArgsType(n, path)
+    or
+    exists(TypeMention tm | result = tm.getTypeAt(path) |
+      exists(Static static |
+        n = static and
+        tm = static.getTypeRepr()
+      )
+      or
+      exists(Const c |
+        n = c and
+        tm = c.getTypeRepr()
+      )
+    )
   }
 
   predicate inferStep(AstNode n1, TypePath path1, AstNode n2, TypePath path2) {
@@ -1085,8 +1086,6 @@ private module Input3 implements InputSig3 {
     or
     result = inferUnknownType(n, path)
   }
-
-  predicate inferTypeForDefaults = M3::inferType/2;
 }
 
 private module M3 = Make3<Input3>;

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

@@ -7,8 +7,8 @@
  *    parameters) and constructs the `TypePath` type used to represent paths into
  *    compound types.
  *
- * 2. `Make2`, which takes as input a definition of type mentions (using the `TypePath`
- *    type) as well as the type hierarchy and type constraints, and constructs the
+ * 2. `Make2`, which (using the `TypePath` type) takes as input a definition of type
+ *    mentions as well as the type hierarchy and type constraints, and constructs the
  *    `Matching` and `IsInstantiationOf` modules, which are core building blocks for
  *    matching type instantiations against type parameters, taking the type hierarchy
  *    and type constraints into account.
@@ -47,8 +47,8 @@
  *
  * where the type of `Default::default()` needs to be inferred from the context, we
  *
- * 1. assign `Default::default()` the special `UnknownType`,
- * 2. using the `cond-then` rule we conclude that the conditional has type `i64`, and
+ * 1. conclude that the conditional has type `i64`, using the `cond-then` rule,
+ * 2. assign `Default::default()` the special `UnknownType`, and
  * 3. since the `else` branch has `UnknownType`, we apply the `cond-else` rule _backwards_
  *    to infer that `Default::default()` has type `i64`.
  *
@@ -1563,9 +1563,11 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
       ) {
         constraint = getATypeParameterConstraint(constrainedTp, target) and
         (
-          constrainedTp = target.getDeclaredType(_, _)
-          or
           constrainedTp = target.getTypeParameter(_)
+          or
+          // a declaration may reference type parameters that are not declared on it,
+          // for type parameters from the enclosing type
+          constrainedTp = target.getDeclaredType(_, _)
         )
       }
 
@@ -1929,6 +1931,13 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
        */
       default predicate cacheRevRef() { none() }
 
+      /**
+       * This predicate must be implemented as an alias for the the `inferType` predicate
+       * defined in this module, and is needed in order to provide default implementations
+       * inside this signature.
+       */
+      Type inferTypeForDefaults(AstNode n, TypePath path);
+
       /** A boolean type. */
       class BoolType extends Type;
 
@@ -1941,10 +1950,6 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
         Location getLocation();
       }
 
-      // todo: remove
-      /** Gets the type annotation that applies to `n`, if any. */
-      TypeMention getTypeAnnotation(AstNode n);
-
       /** An expression. */
       class Expr extends AstNode;
 
@@ -2028,12 +2033,7 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
        * respect to type inference, for example a `const` or `static` in Rust.
        */
       class LocalVariable {
-        /**
-         * Gets the AST node that defines this variable.
-         *
-         * If this variable is explicitly typed, then the type annotation must be
-         * applied to the defining node in `getTypeAnnotation`.
-         */
+        /** Gets the AST node that defines this variable. */
         AstNode getDefiningNode();
 
         /** Gets an access to this variable. */
@@ -2381,15 +2381,6 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
        * nodes where `inferStep` cannot be used, such as leaf nodes in the AST.
        */
       Type inferTypeSpecific(AstNode n, TypePath path);
-
-      /**
-       * Gets the inferred type of `n` at `path`.
-       *
-       * This predicate must be implemented as an alias for the the `inferType` predicate
-       * defined in this module, and is needed in order to provide default implementations
-       * inside this signature.
-       */
-      Type inferTypeForDefaults(AstNode n, TypePath path);
     }
 
     module Make3<InputSig3 Input3> {
@@ -2398,8 +2389,6 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
       /** Gets the type of `n`, which has an explicit type annotation. */
       pragma[nomagic]
       private Type inferAnnotatedType(AstNode n, TypePath path) {
-        result = getTypeAnnotation(n).getTypeAt(path)
-        or
         result = n.(Cast).getType().getTypeAt(path)
         or
         exists(LocalVariableDeclaration decl |
@@ -2961,7 +2950,12 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
         class Declaration extends ParameterizableFinal {
           TypeParameter getTypeParameter(int pos) {
             InvocationTypeQualifierMatching::typeMatch(_, _, this, _, _, result) and
-            pos = -getTypeParameterId(result) - 1
+            pos = -getTypeParameterId(result) - 2
+            or
+            // blanket implementations in Rust have a declaring type that is a type parameter;
+            // those should be matched against the entire type qualifier
+            result = this.getDeclaringType(TypePath::nil()) and
+            pos = -1
             or
             result = super.getTypeParameter(pos)
             // none()
@@ -2972,9 +2966,6 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
             or
             dpos = getReturnPosition() and
             result = getParameterizableType(this, path)
-            // or
-            // dpos = getDeclaringPosition() and
-            // result = this.getDeclaringType(path)
           }
         }
 
@@ -2989,9 +2980,12 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
           Type getTypeArgument(int pos, TypePath path) {
             exists(TypeParameter tp |
               InvocationTypeQualifierMatching::typeMatch(this, _, _, path, result, tp) and
-              pos = -getTypeParameterId(tp) - 1
+              pos = -getTypeParameterId(tp) - 2
             )
             or
+            pos = -1 and
+            result = this.getTypeQualifier(path)
+            or
             result = super.getTypeArgument(pos, path)
           }