QL: Merge pull request #27 from github/newtype-call

Resolve `newtype` constructor calls

Author: hvitved

ql/src/codeql_ql/ast/Ast.qll

@@ -650,6 +650,8 @@ class NewTypeBranch extends TNewTypeBranch, TypeDeclaration {
   /** Gets the body of this branch. */
   Formula getBody() { toGenerated(result) = branch.getChild(_).(Generated::Body).getChild() }
 
+  NewType getNewType() { result.getABranch() = this }
+
   override AstNode getAChild(string pred) {
     result = super.getAChild(pred)
     or

ql/src/codeql_ql/ast/internal/Module.qll

@@ -166,7 +166,11 @@ predicate resolveModuleExpr(ModuleExpr me, FileOrModule m) {
   )
 }
 
-boolean getPublicBool(ModuleMember m) { if m.isPrivate() then result = false else result = true }
+boolean getPublicBool(AstNode n) {
+  if n.(ModuleMember).isPrivate() or n.(NewTypeBranch).getNewType().isPrivate()
+  then result = false
+  else result = true
+}
 
 /**
  * Holds if `container` defines module `m` with name `name`.

ql/src/codeql_ql/ast/internal/Predicate.qll

@@ -1,18 +1,30 @@
 import ql
 private import Builtins
 private import codeql_ql.ast.internal.Module
+private import codeql_ql.ast.internal.AstNodes as AstNodes
 
-private predicate definesPredicate(FileOrModule m, string name, ClasslessPredicate p, boolean public) {
+private class TClasslessPredicateOrNewTypeBranch =
+  AstNodes::TClasslessPredicate or AstNodes::TNewTypeBranch;
+
+string getPredicateName(TClasslessPredicateOrNewTypeBranch p) {
+  result = p.(ClasslessPredicate).getName() or
+  result = p.(NewTypeBranch).getName()
+}
+
+private predicate definesPredicate(
+  FileOrModule m, string name, int arity, TClasslessPredicateOrNewTypeBranch p, boolean public
+) {
   m = getEnclosingModule(p) and
-  name = p.getName() and
-  public = getPublicBool(p)
+  name = getPredicateName(p) and
+  public = getPublicBool(p) and
+  arity = [p.(ClasslessPredicate).getArity(), count(p.(NewTypeBranch).getField(_))]
   or
   // import X
   exists(Import imp, FileOrModule m0 |
     m = getEnclosingModule(imp) and
     m0 = imp.getResolvedModule() and
     not exists(imp.importedAs()) and
-    definesPredicate(m0, name, p, true) and
+    definesPredicate(m0, name, arity, p, true) and
     public = getPublicBool(imp)
   )
   or
@@ -21,7 +33,8 @@ private predicate definesPredicate(FileOrModule m, string name, ClasslessPredica
     m = getEnclosingModule(alias) and
     name = alias.getName() and
     resolvePredicateExpr(alias.getAlias(), p) and
-    public = getPublicBool(alias)
+    public = getPublicBool(alias) and
+    arity = alias.getArity()
   )
 }
 
@@ -34,8 +47,7 @@ predicate resolvePredicateExpr(PredicateExpr pe, ClasslessPredicate p) {
     m = pe.getQualifier().getResolvedModule() and
     public = true
   |
-    definesPredicate(m, pe.getName(), p, public) and
-    count(p.getParameter(_)) = pe.getArity()
+    definesPredicate(m, pe.getName(), count(p.getParameter(_)), p, public)
   )
 }
 
@@ -54,8 +66,7 @@ private predicate resolvePredicateCall(PredicateCall pc, PredicateOrBuiltin p) {
     m = pc.getQualifier().getResolvedModule() and
     public = true
   |
-    definesPredicate(m, pc.getPredicateName(), p.getDeclaration(), public) and
-    p.getArity() = pc.getNumberOfArguments()
+    definesPredicate(m, pc.getPredicateName(), pc.getNumberOfArguments(), p.getDeclaration(), public)
   )
 }
 
@@ -74,6 +85,7 @@ predicate resolveCall(Call c, PredicateOrBuiltin p) {
 
 private newtype TPredOrBuiltin =
   TPred(Predicate p) or
+  TNewTypeBranch(NewTypeBranch b) or
   TBuiltinClassless(string ret, string name, string args) { isBuiltinClassless(ret, name, args) } or
   TBuiltinMember(string qual, string ret, string name, string args) {
     isBuiltinMember(qual, ret, name, args)
@@ -101,7 +113,7 @@ class PredicateOrBuiltin extends TPredOrBuiltin {
     )
   }
 
-  Predicate getDeclaration() { none() }
+  AstNode getDeclaration() { none() }
 
   Type getDeclaringType() { none() }
 
@@ -127,6 +139,7 @@ private class DefinedPredicate extends PredicateOrBuiltin, TPred {
 
   override Type getParameterType(int i) { result = decl.getParameter(i).getType() }
 
+  // Can be removed when all types can be resolved
   override int getArity() { result = decl.getArity() }
 
   override Type getDeclaringType() {
@@ -140,6 +153,27 @@ private class DefinedPredicate extends PredicateOrBuiltin, TPred {
   }
 }
 
+private class DefinedNewTypeBranch extends PredicateOrBuiltin, TNewTypeBranch {
+  NewTypeBranch b;
+
+  DefinedNewTypeBranch() { this = TNewTypeBranch(b) }
+
+  override NewTypeBranch getDeclaration() { result = b }
+
+  override string getName() { result = b.getName() }
+
+  override NewTypeBranchType getReturnType() { result.getDeclaration() = b }
+
+  override Type getParameterType(int i) { result = b.getField(i).getType() }
+
+  // Can be removed when all types can be resolved
+  override int getArity() { result = count(b.getField(_)) }
+
+  override Type getDeclaringType() { none() }
+
+  override predicate isPrivate() { b.getNewType().isPrivate() }
+}
+
 private class TBuiltin = TBuiltinClassless or TBuiltinMember;
 
 class BuiltinPredicate extends PredicateOrBuiltin, TBuiltin { }
@@ -183,6 +217,7 @@ module PredConsistency {
 
   query predicate noResolveCall(Call c) {
     not resolveCall(c, _) and
+    not c instanceof NoneCall and
     not c.getLocation().getFile().getAbsolutePath().regexpMatch(".*/(test|examples)/.*")
   }
 

ql/src/codeql_ql/ast/internal/Type.qll

@@ -61,11 +61,24 @@ class Type extends TType {
     )
   }
 
+  pragma[nomagic]
+  private predicate getClassPredicate0(string name, int arity, PredicateOrBuiltin p, Type t) {
+    p = classPredCandidate(this, name, arity) and
+    t = p.getDeclaringType().getASuperType+()
+  }
+
+  pragma[nomagic]
+  private predicate getClassPredicate1(
+    string name, int arity, PredicateOrBuiltin p1, PredicateOrBuiltin p2
+  ) {
+    getClassPredicate0(name, arity, p1, p2.getDeclaringType()) and
+    p2 = classPredCandidate(this, name, arity)
+  }
+
+  pragma[nomagic]
   PredicateOrBuiltin getClassPredicate(string name, int arity) {
     result = classPredCandidate(this, name, arity) and
-    not exists(PredicateOrBuiltin other | other = classPredCandidate(this, name, arity) |
-      other.getDeclaringType().getASuperType+() = result.getDeclaringType()
-    )
+    not getClassPredicate1(name, arity, _, result)
   }
 }
 

ql/src/codeql_ql/ast/internal/Variable.qll

@@ -10,34 +10,43 @@ class VariableScope extends TScope, AstNode {
   VariableScope getOuterScope() { result = scopeOf(this) }
 
   /** Gets a variable declared directly in this scope. */
-  VarDef getADefinition() { result.getParent() = this }
+  VarDef getADefinition(string name) {
+    result.getParent() = this and
+    name = result.getName()
+  }
 
   /** Holds if this scope contains variable `decl`, either directly or inherited. */
-  predicate containsVar(VarDef decl) {
-    not this instanceof Class and
-    decl = this.getADefinition()
-    or
-    decl = this.(Select).getExpr(_).(AsExpr)
-    or
-    decl = this.(Aggregate).getExpr(_).(AsExpr)
-    or
-    decl = this.(ExprAggregate).getExpr(_).(AsExpr)
-    or
-    this.getOuterScope().containsVar(decl) and
-    not this.getADefinition().getName() = decl.getName()
+  predicate containsVar(VarDef decl, string name) {
+    name = decl.getName() and
+    (
+      not this instanceof Class and
+      decl = this.getADefinition(name)
+      or
+      decl = this.(Select).getExpr(_).(AsExpr)
+      or
+      decl = this.(Aggregate).getExpr(_).(AsExpr)
+      or
+      decl = this.(ExprAggregate).getExpr(_).(AsExpr)
+      or
+      this.getOuterScope().containsVar(decl, name) and
+      not exists(this.getADefinition(name))
+    )
   }
 
   /** Holds if this scope contains field `decl`, either directly or inherited. */
-  predicate containsField(VarDef decl) {
-    decl = this.(Class).getAField()
-    or
-    this.getOuterScope().containsField(decl) and
-    not this.getADefinition().getName() = decl.getName()
-    or
-    exists(VariableScope sup |
-      sup = this.(Class).getASuperType().getResolvedType().(ClassType).getDeclaration() and
-      sup.containsField(decl) and
-      not this.(Class).getAField().getName() = decl.getName()
+  predicate containsField(VarDef decl, string name) {
+    name = decl.getName() and
+    (
+      decl = this.(Class).getAField()
+      or
+      this.getOuterScope().containsField(decl, name) and
+      not exists(this.getADefinition(name))
+      or
+      exists(VariableScope sup |
+        sup = this.(Class).getASuperType().getResolvedType().(ClassType).getDeclaration() and
+        sup.containsField(decl, name) and
+        not this.(Class).getAField().getName() = name
+      )
     )
   }
 }
@@ -56,15 +65,9 @@ private string getName(Identifier i) {
   )
 }
 
-predicate resolveVariable(Identifier i, VarDef decl) {
-  scopeOf(i).containsVar(decl) and
-  decl.getName() = getName(i)
-}
+predicate resolveVariable(Identifier i, VarDef decl) { scopeOf(i).containsVar(decl, getName(i)) }
 
-predicate resolveField(Identifier i, VarDef decl) {
-  scopeOf(i).containsField(decl) and
-  decl.getName() = getName(i)
-}
+predicate resolveField(Identifier i, VarDef decl) { scopeOf(i).containsField(decl, getName(i)) }
 
 module VarConsistency {
   query predicate multipleVarDefs(VarAccess v, VarDef decl) {