dbg2

Author: hvitved

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

@@ -1286,6 +1286,18 @@ private module MethodResolution {
 
     private Type getReceiverTypeAt(TypePath path) {
       result = this.getArgumentTypeAt(any(ArgumentPosition pos | pos.isSelf()), path)
+      or
+      exists(Function f, SelfParam self, TypePath prefix, TypePath suffix |
+        f = CallExprImpl::getResolvedFunction(this) and
+        self = f.getSelfParam() and
+        result = getCallExprTypeQualifier(this, suffix) and
+        path = prefix.append(suffix)
+      |
+        prefix = getSelfParamSelfPath(self)
+        or
+        not self.hasTypeRepr() and
+        if self.isRef() then prefix = TypePath::singleton(TRefTypeParameter()) else prefix.isEmpty()
+      )
     }
 
     /**
@@ -1557,20 +1569,6 @@ private module MethodResolution {
       forall(ItemNode i | i = CallExprImpl::getResolvedFunction(this) | i instanceof Method)
     }
 
-    /**
-     * Holds if this call has a type qualifier, and we are able to resolve,
-     * using path resolution, the method to a member of `impl`.
-     *
-     * When this is the case, we still want to check that the type qualifier
-     * is an instance of the type being implemented, which is done in
-     * `TypeQualifierIsInstantiationOfImplSelfInput`.
-     */
-    pragma[nomagic]
-    predicate hasTypeQualifiedCandidate(ImplItemNode impl) {
-      exists(getCallExprTypeQualifier(this, _)) and
-      CallExprImpl::getResolvedFunction(this) = impl.getASuccessor(_)
-    }
-
     pragma[nomagic]
     override predicate hasNameAndArity(string name, int arity) {
       name = CallExprImpl::getFunctionPath(this).getText() and
@@ -1584,11 +1582,6 @@ private module MethodResolution {
       result = this.getArgList().getArg(pos.asPosition() + 1)
     }
 
-    // needed for `TypeQualifierIsInstantiationOfImplSelfInput`
-    Type getTypeAt(TypePath path) {
-      result = substituteLookupTraits(getCallExprTypeQualifier(this, path))
-    }
-
     override predicate supportsAutoDerefAndBorrow() { none() }
   }
 
@@ -1699,18 +1692,9 @@ private module MethodResolution {
       )
     }
 
-    pragma[nomagic]
-    private predicate typeQualifierIsInstantiationOf(ImplOrTraitItemNode i) {
-      TypeQualifierIsInstantiationOfImplSelf::isInstantiationOf(mc_, i, _)
-    }
-
     pragma[nomagic]
     private predicate argIsInstantiationOf(ImplOrTraitItemNode i, string name, int arity) {
-      (
-        ReceiverIsInstantiationOfSelfParam::argIsInstantiationOf(this, i, _)
-        or
-        this.typeQualifierIsInstantiationOf(i)
-      ) and
+      ReceiverIsInstantiationOfSelfParam::argIsInstantiationOf(this, i, _) and
       mc_.hasNameAndArity(name, arity)
     }
 
@@ -1833,6 +1817,7 @@ private module MethodResolution {
       MethodCallCand mcc, ImplItemNode impl, TraitItemNode trait, AssocFunctionType selfType,
       MethodCall mc, Method m, string name, int arity, TypePath strippedTypePath, Type strippedType
     ) {
+      // mc = Debug::getRelevantLocatable() and
       potentialInstantiationOf0(mcc, impl, selfType, mc, m, name, arity, strippedTypePath,
         strippedType) and
       m = trait.getAnAssocItem()
@@ -1846,6 +1831,7 @@ private module MethodResolution {
         MethodCall mc, Method m, string name, int arity, TypePath strippedTypePath,
         Type strippedType
       |
+        // mc = Debug::getRelevantLocatable() and
         potentialInstantiationOf0(mcc, i, selfType, mc, m, name, arity, strippedTypePath,
           strippedType) and
         not (
@@ -1916,45 +1902,6 @@ private module MethodResolution {
   private module ReceiverIsNotInstantiationOfBlanketLikeSelfParam =
     ArgIsInstantiationOf<MethodCallCand, ReceiverIsNotInstantiationOfBlanketLikeSelfParamInput>;
 
-  /**
-   * A configuration for matching the type qualifier of a method call
-   * against the type being implemented in an `impl` block. For example,
-   * in `Foo::<Bar>::m(x)`, we check that the type `Foo<Bar>` is an
-   * instance of the type being implemented.
-   */
-  private module TypeQualifierIsInstantiationOfImplSelfInput implements
-    IsInstantiationOfInputSig<MethodCallCallExpr, TypeMentionTypeTree>
-  {
-    pragma[nomagic]
-    private predicate potentialInstantiationOf0(
-      MethodCallCallExpr ce, ImplItemNode impl, TypeMentionTypeTree constraint
-    ) {
-      ce.hasTypeQualifiedCandidate(impl) and
-      constraint = impl.getSelfPath()
-    }
-
-    pragma[nomagic]
-    predicate potentialInstantiationOf(
-      MethodCallCallExpr ce, TypeAbstraction abs, TypeMentionTypeTree constraint
-    ) {
-      potentialInstantiationOf0(ce, abs, constraint) and
-      if abs.(Impl).hasTrait()
-      then
-        // inherent methods take precedence over trait methods, so only allow
-        // trait methods when there are no matching inherent methods
-        MkMethodCallCand(ce, _, _).(MethodCallCand).hasNoInherentTarget()
-      else any()
-    }
-
-    predicate relevantConstraint(TypeMentionTypeTree constraint) {
-      potentialInstantiationOf0(_, _, constraint)
-    }
-  }
-
-  private module TypeQualifierIsInstantiationOfImplSelf =
-    IsInstantiationOf<MethodCallCallExpr, TypeMentionTypeTree,
-      TypeQualifierIsInstantiationOfImplSelfInput>;
-
   /**
    * A configuration for matching the types of positional arguments against the
    * types of parameters, when needed to disambiguate the call.
@@ -3494,8 +3441,8 @@ private module Debug {
   Locatable getRelevantLocatable() {
     exists(string filepath, int startline, int startcolumn, int endline, int endcolumn |
       result.getLocation().hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn) and
-      filepath.matches("%/sqlx.rs") and
-      startline = [56 .. 60]
+      filepath.matches("%/main.rs") and
+      startline = 590
     )
   }
 

rust/ql/lib/codeql/rust/internal/TypeMention.qll

@@ -164,7 +164,7 @@ class NonAliasPathTypeMention extends PathTypeMention {
 
   /** Gets the type mention in this path for the type parameter `tp`, if any. */
   pragma[nomagic]
-  private TypeMention getTypeMentionForTypeParameter(TypeParameter tp) {
+  TypeMention getTypeMentionForTypeParameter(TypeParameter tp) {
     exists(int i |
       result = this.getPositionalTypeArgument(pragma[only_bind_into](i)) and
       tp = this.resolveRootType().getPositionalTypeParameter(pragma[only_bind_into](i))
@@ -390,6 +390,34 @@ TypeMention getSelfParamTypeMention(SelfParam self) {
   result = self.getTypeRepr()
 }
 
+pragma[nomagic]
+private predicate pathToSelfParamSelf(TypePath path, TypeMention parent) {
+  exists(TypeMention self |
+    self.getParentNode*() instanceof SelfParam and
+    parent = self and
+    path.isEmpty()
+  |
+    self = any(TraitItemNode trait).getASelfPath()
+    or
+    self instanceof ImplSelfMention
+  )
+  or
+  pathToSelfParamSelf(path, parent.(PathTypeRepr).getPath())
+  or
+  exists(TypePath suffix, TypeMention tm, TypeParameter tp |
+    pathToSelfParamSelf(suffix, tm) and
+    path = TypePath::singleton(tp).append(suffix)
+  |
+    tm = parent.(NonAliasPathTypeMention).getTypeMentionForTypeParameter(tp)
+    or
+    tm = parent.(RefTypeRepr).getTypeRepr() and
+    tp = TRefTypeParameter()
+  )
+}
+
+pragma[nomagic]
+TypePath getSelfParamSelfPath(SelfParam self) { pathToSelfParamSelf(result, self.getTypeRepr()) }
+
 class DynTraitTypeReprMention extends TypeMention instanceof DynTraitTypeRepr {
   private DynTraitType dynType;
 

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

@@ -6937,3 +6937,4 @@ inferType
 | pattern_matching.rs:827:5:827:7 | f(...) |  | {EXTERNAL LOCATION} | Option |
 | pattern_matching.rs:827:5:827:7 | f(...) | T | file://:0:0:0:0 | () |
 testFailures
+| main.rs:590:21:590:82 | //... | Fixed spurious result: target=MyTrait1::m |