Unified: Track all local name kinds in one pass

unified/extractor/src/languages/swift/swift.rs

@@ -1065,19 +1065,51 @@ fn translation_rules() -> Vec<Rule<SwiftContext>> {
         // A nominal type's `inheritanceClause` (`: Base, Proto`) becomes a list
         // of `base_type`s, one per inherited type. Each declaration keyword
         // gets its own rule; the bodies are identical but for the keyword.
+        rule!(
+            (genericParameter
+                attributes: _* @attrs
+                specifier: _? @@spec
+                name: @@name
+                inheritedType: _? @bound)
+            =>
+            (type_parameter
+                modifier: {attrs}
+                modifier: (modifier #{spec})?
+                name: (identifier #{name})
+                bound: {bound})
+        ),
+        rule!(
+            (genericRequirement
+                requirement: (conformanceRequirement leftType: @ty rightType: @bound))
+            =>
+            (bound_type_constraint type: {ty} bound: {bound})
+        ),
+        rule!(
+            (genericRequirement
+                requirement: (sameTypeRequirement leftType: @left rightType: @right))
+            =>
+            (equality_type_constraint left: {left} right: {right})
+        ),
         // Class declaration with body containing members
         rule!(
             (classDecl
                 classKeyword: @kind
                 modifiers: _* @mods
                 name: @name
+                genericParameterClause: (genericParameterClause
+                    parameters: _* @params
+                    genericWhereClause: (genericWhereClause requirements: _* @parameter_constraints)?)?
                 inheritanceClause: (inheritanceClause inheritedTypes: (inheritedType type: @bases)*)?
+                genericWhereClause: (genericWhereClause requirements: _* @declaration_constraints)?
                 memberBlock: (memberBlock members: _* @members))
             =>
             (class_like_declaration
                 modifier: (modifier #{kind})
                 modifier: {mods}
                 name: (identifier #{name})
+                type_parameter: {params}
+                type_constraint: {parameter_constraints}
+                type_constraint: {declaration_constraints}
                 base_type: {bases.into_iter().map(|ty| tree!((base_type type: {ty})))}
                 member: {members})
         ),
@@ -1087,13 +1119,20 @@ fn translation_rules() -> Vec<Rule<SwiftContext>> {
                 enumKeyword: @kind
                 modifiers: _* @mods
                 name: @name
+                genericParameterClause: (genericParameterClause
+                    parameters: _* @params
+                    genericWhereClause: (genericWhereClause requirements: _* @parameter_constraints)?)?
                 inheritanceClause: (inheritanceClause inheritedTypes: (inheritedType type: @bases)*)?
+                genericWhereClause: (genericWhereClause requirements: _* @declaration_constraints)?
                 memberBlock: (memberBlock members: _* @members))
             =>
             (class_like_declaration
                 modifier: (modifier #{kind})
                 modifier: {mods}
                 name: (identifier #{name})
+                type_parameter: {params}
+                type_constraint: {parameter_constraints}
+                type_constraint: {declaration_constraints}
                 base_type: {bases.into_iter().map(|ty| tree!((base_type type: {ty})))}
                 member: {members})
         ),
@@ -1103,13 +1142,20 @@ fn translation_rules() -> Vec<Rule<SwiftContext>> {
                 structKeyword: @kind
                 modifiers: _* @mods
                 name: @name
+                genericParameterClause: (genericParameterClause
+                    parameters: _* @params
+                    genericWhereClause: (genericWhereClause requirements: _* @parameter_constraints)?)?
                 inheritanceClause: (inheritanceClause inheritedTypes: (inheritedType type: @bases)*)?
+                genericWhereClause: (genericWhereClause requirements: _* @declaration_constraints)?
                 memberBlock: (memberBlock members: _* @members))
             =>
             (class_like_declaration
                 modifier: (modifier #{kind})
                 modifier: {mods}
                 name: (identifier #{name})
+                type_parameter: {params}
+                type_constraint: {parameter_constraints}
+                type_constraint: {declaration_constraints}
                 base_type: {bases.into_iter().map(|ty| tree!((base_type type: {ty})))}
                 member: {members})
         ),
@@ -1119,13 +1165,17 @@ fn translation_rules() -> Vec<Rule<SwiftContext>> {
                 protocolKeyword: @kind
                 modifiers: _* @mods
                 name: @name
+                genericParameterClause: (genericParameterClause parameters: _* @params)?
                 inheritanceClause: (inheritanceClause inheritedTypes: (inheritedType type: @bases)*)?
+                genericWhereClause: (genericWhereClause requirements: _* @declaration_constraints)?
                 memberBlock: (memberBlock members: _* @members))
             =>
             (class_like_declaration
                 modifier: (modifier #{kind})
                 modifier: {mods}
                 name: (identifier #{name})
+                type_parameter: {params}
+                type_constraint: {declaration_constraints}
                 base_type: {bases.into_iter().map(|ty| tree!((base_type type: {ty})))}
                 member: {members})
         ),

unified/extractor/tests/corpus/swift/types/generic-class-parameters-and-constraints.output

@@ -0,0 +1,94 @@
+class Box<T: Equatable, U> where U: Equatable, U == T {
+}
+
+---
+
+sourceFile
+  endOfFileToken: endOfFile
+  statements:
+    codeBlockItem
+      item:
+        classDecl
+          attributes:
+          name: identifier "Box"
+          genericParameterClause:
+            genericParameterClause
+              parameters:
+                genericParameter
+                  colon: :
+                  attributes:
+                  name: identifier "T"
+                  trailingComma: ,
+                  inheritedType:
+                    identifierType
+                      name: identifier "Equatable"
+                genericParameter
+                  attributes:
+                  name: identifier "U"
+              leftAngle: <
+              rightAngle: >
+          genericWhereClause:
+            genericWhereClause
+              requirements:
+                genericRequirement
+                  trailingComma: ,
+                  requirement:
+                    conformanceRequirement
+                      colon: :
+                      leftType:
+                        identifierType
+                          name: identifier "U"
+                      rightType:
+                        identifierType
+                          name: identifier "Equatable"
+                genericRequirement
+                  requirement:
+                    sameTypeRequirement
+                      equal: binaryOperator "=="
+                      leftType:
+                        identifierType
+                          name: identifier "U"
+                      rightType:
+                        identifierType
+                          name: identifier "T"
+              whereKeyword: where
+          memberBlock:
+            memberBlock
+              leftBrace: {
+              rightBrace: }
+              members:
+          modifiers:
+          classKeyword: class
+
+---
+
+top_level
+  body:
+    block
+      stmt:
+        class_like_declaration
+          modifier: modifier "class"
+          name: identifier "Box"
+          type_parameter:
+            type_parameter
+              name: identifier "T"
+              bound:
+                named_type_expr
+                  name: identifier "Equatable"
+            type_parameter
+              name: identifier "U"
+          type_constraint:
+            bound_type_constraint
+              type:
+                named_type_expr
+                  name: identifier "U"
+              bound:
+                named_type_expr
+                  name: identifier "Equatable"
+            equality_type_constraint
+              left:
+                named_type_expr
+                  name: identifier "U"
+              right:
+                named_type_expr
+                  name: identifier "T"

unified/extractor/tests/corpus/swift/types/generic-class-parameters-and-constraints.swift

@@ -0,0 +1,2 @@
+class Box<T: Equatable, U> where U: Equatable, U == T {
+}

unified/ql/lib/codeql/unified/internal/AstExtra.qll

@@ -52,4 +52,9 @@ module Public {
       result = this.getValue().regexpCapture("(?s)/\\*(.*)\\*/", 1)
     }
   }
+
+  /** A `Stmt` at the top-level. */
+  final class TopLevelStmt extends Stmt {
+    TopLevelStmt() { this = any(TopLevel t).getBody().getAStmt() }
+  }
 }

unified/ql/lib/codeql/unified/internal/Variables.qll

@@ -130,6 +130,8 @@ private module LocalNameBindingInput implements LocalNameBindingInputSig<Locatio
   }
 
   abstract class SiblingShadowingDecl extends AstNode {
+    abstract AstNode getPattern();
+
     /**
      * Gets the right-hand side of this declaration.
      *
@@ -149,26 +151,38 @@ private module LocalNameBindingInput implements LocalNameBindingInputSig<Locatio
 
   private class LocalVariableDeclarationSiblingShadowingDecl extends SiblingShadowingDecl instanceof LocalVariableDeclaration
   {
+    LocalVariableDeclarationSiblingShadowingDecl() { not this instanceof TopLevelStmt }
+
+    override Pattern getPattern() { result = LocalVariableDeclaration.super.getPattern() }
+
     override AstNode getRhs() { result = LocalVariableDeclaration.super.getValue() }
 
     override AstNode getElse() { none() }
   }
 
   private class PatternGuardExprSiblingShadowingDecl extends SiblingShadowingDecl instanceof PatternGuardExpr
   {
+    override Pattern getPattern() { result = PatternGuardExpr.super.getPattern() }
+
     override AstNode getRhs() { result = PatternGuardExpr.super.getValue() }
 
     override AstNode getElse() { none() }
   }
 
   private predicate bindingContext(AstNode pattern, AstNode scope) {
-    exists(LocalVariableDeclaration decl |
-      scope = decl and // LocalVariableDeclaration is a ShadowingSiblingDecl, it must use itself as the scope
+    exists(SiblingShadowingDecl decl |
+      scope = decl and
       pattern = decl.getPattern()
     )
     or
-    exists(LocalFunctionDeclaration func |
-      scope = func.getDeclaringBlock() and
+    exists(VariableDeclaration decl |
+      not decl instanceof SiblingShadowingDecl and
+      getChild(scope, _) = decl and
+      pattern = decl.getPattern()
+    )
+    or
+    exists(FunctionDeclaration func |
+      getChild(scope, _) = func and
       pattern = func.getName()
     )
     or
@@ -192,12 +206,37 @@ private module LocalNameBindingInput implements LocalNameBindingInputSig<Locatio
       pattern = stmt.getPattern()
     )
     or
-    bindingContext(pattern.(Pattern).getEnclosingPattern(), scope)
+    exists(ClassLikeDeclaration cls |
+      getChild(scope, _) = cls and
+      pattern = cls.getName()
+    )
+    or
+    exists(TypeAliasDeclaration decl |
+      getChild(scope, _) = decl and
+      pattern = decl.getName()
+    )
     or
-    exists(PatternGuardExpr expr |
-      pattern = expr.getPattern() and
-      scope = expr
+    exists(TypeParameter param |
+      scope = param.getParent() and
+      pattern = param.getName()
     )
+    or
+    exists(AssociatedTypeDeclaration decl |
+      getChild(scope, _) = decl and
+      pattern = decl.getName()
+    )
+    or
+    exists(AccessorDeclaration decl |
+      getChild(scope, _) = decl and
+      pattern = decl.getName()
+    )
+    or
+    exists(ImportDeclaration imprt |
+      getChild(scope, _) = imprt and
+      pattern = imprt.getPattern()
+    )
+    or
+    bindingContext(pattern.(Pattern).getEnclosingPattern(), scope)
   }
 
   /**
@@ -243,6 +282,11 @@ private module LocalNameBindingInput implements LocalNameBindingInputSig<Locatio
     or
     n.(NamePattern).getIdentifier().getValue() = name
     or
+    exists(NamedTypeExpr expr | n = expr |
+      not exists(expr.getQualifier()) and
+      expr.getName().getValue() = name
+    )
+    or
     n = any(LocalFunctionDeclaration f).getName() and
     n.(Identifier).getValue() = name
   }

unified/ql/test/library-tests/variables/class_scope.swift

@@ -0,0 +1,73 @@
+class A {
+    static func static_before() {
+        print(staticVar) // $ access=staticVar
+        B(); // $ access=A.B
+        let b: B = nil // $ access=A.B
+        let c: C = nil // $ access=A.C
+    }
+    func instance_before() {
+        print(instanceVar) // $ access=instanceVar
+        B(); // $ access=A.B
+        let b: B = nil // $ access=A.B
+        let c: C = nil // $ access=A.C
+    }
+
+    private static let staticVar = 123
+    private let instanceVar = 456
+
+    class B {} // name=A.B
+    typealias C = B // $ access=A.B // name=A.C
+
+    static func static_after() {
+        print(staticVar) // $ access=staticVar
+        B(); // $ access=A.B
+        let b: B = nil // $ access=A.B
+        let c: C = nil // $ access=A.C
+
+    }
+    func instance_after() {
+        print(instanceVar) // $ access=instanceVar
+        B(); // $ access=A.B
+        let b: B = nil // $ access=A.B
+        let c: C = nil // $ access=A.C
+    }
+}
+
+class Base {} // name=top.Base
+
+// Base types and type parameter bounds can't see members in the class body
+class C : Base { // $ MISSING: access=top.Base SPURIOUS: access=C.Base
+    class Base {} // name=C.Base
+}
+
+class D<T : Base> { // $ MISSING: access=top.Base SPURIOUS: access=D.Base
+    class Base {} // name=D.Base
+}
+
+class E<T> where T : Base { // $ access=T MISSING: access=top.Base SPURIOUS: access=E.Base
+    class Base {} // name=E.Base
+}
+
+// Base types and type parameter bounds can see type parameters
+class F<TypeParamF> :
+    D<TypeParamF> { // $ access=D access=TypeParamF
+}
+
+class G<TypeParamG :
+    D<TypeParamG>> { // $ access=D access=TypeParamG
+}
+
+class H<TypeParamH> where
+    TypeParamH : Base { // $ access=TypeParamH access=top.Base
+}
+
+// Type parameter bounds can see other type parameters, even if declared later
+class I<
+    T1 : D<T2>, // $ access=D access=I.T2
+    T2> { // name=I.T2
+}
+
+// Members can see type parameters.
+class J<TypeParamI> {
+    let x: TypeParamI; // $ access=TypeParamI
+}