QL: Merge pull request #24 from github/types

Resolve calls

Author: hvitved

ql/src/codeql_ql/ast/Ast.qll

@@ -9,10 +9,12 @@ bindingset[name]
 private string directMember(string name) { result = name + "()" }
 
 bindingset[name, i]
-private string indexedMember(string name, int i) { result = name + "(_)" }
+private string indexedMember(string name, int i) { result = name + "(_)" and exists(i) }
 
 bindingset[name, index]
-private string stringIndexedMember(string name, string index) { result = name + "(_)" }
+private string stringIndexedMember(string name, string index) {
+  result = name + "(_)" and exists(index)
+}
 
 /** An AST node of a QL program */
 class AstNode extends TAstNode {
@@ -110,17 +112,18 @@ class Predicate extends TPredicate, AstNode {
   /**
    * Gets the return type (if any) of the predicate.
    */
-  TypeExpr getReturnType() { none() }
+  TypeExpr getReturnTypeExpr() { none() }
+
+  Type getReturnType() { result = this.getReturnTypeExpr().getResolvedType() }
 
-  // TODO: ReturnType.
   override AstNode getAChild(string pred) {
     result = super.getAChild(pred)
     or
     pred = directMember("getBody") and result = this.getBody()
     or
     exists(int i | pred = indexedMember("getParameter", i) and result = this.getParameter(i))
     or
-    pred = directMember("getReturnType") and result = this.getReturnType()
+    pred = directMember("getReturnTypeExpr") and result = this.getReturnTypeExpr()
   }
 
   override string getAPrimaryQlClass() { result = "Predicate" }
@@ -199,7 +202,7 @@ class ClasslessPredicate extends TClasslessPredicate, Predicate, ModuleDeclarati
       rank[i](Generated::VarDecl decl, int index | decl = pred.getChild(index) | decl order by index)
   }
 
-  override TypeExpr getReturnType() { toGenerated(result) = pred.getReturnType() }
+  override TypeExpr getReturnTypeExpr() { toGenerated(result) = pred.getReturnType() }
 
   override AstNode getAChild(string pred_name) {
     result = Predicate.super.getAChild(pred_name)
@@ -210,7 +213,7 @@ class ClasslessPredicate extends TClasslessPredicate, Predicate, ModuleDeclarati
     or
     exists(int i | pred_name = indexedMember("getParameter", i) and result = this.getParameter(i))
     or
-    pred_name = directMember("getReturnType") and result = this.getReturnType()
+    pred_name = directMember("getReturnTypeExpr") and result = this.getReturnTypeExpr()
   }
 }
 
@@ -248,7 +251,7 @@ class ClassPredicate extends TClassPredicate, Predicate {
 
   predicate overrides(ClassPredicate other) { predOverrides(this, other) }
 
-  override TypeExpr getReturnType() { toGenerated(result) = pred.getReturnType() }
+  override TypeExpr getReturnTypeExpr() { toGenerated(result) = pred.getReturnType() }
 
   override AstNode getAChild(string pred_name) {
     result = super.getAChild(pred_name)
@@ -257,7 +260,7 @@ class ClassPredicate extends TClassPredicate, Predicate {
     or
     exists(int i | pred_name = indexedMember("getParameter", i) and result = this.getParameter(i))
     or
-    pred_name = directMember("getReturnType") and result = this.getReturnType()
+    pred_name = directMember("getReturnTypeExpr") and result = this.getReturnTypeExpr()
   }
 }
 
@@ -290,6 +293,8 @@ class VarDef extends TVarDef, AstNode {
   /** Gets the name of the declared variable. */
   string getName() { none() }
 
+  Type getType() { none() }
+
   override string getAPrimaryQlClass() { result = "VarDef" }
 
   override string toString() { result = this.getName() }
@@ -305,9 +310,11 @@ class VarDecl extends TVarDecl, VarDef {
 
   override string getName() { result = var.getChild(1).(Generated::VarName).getChild().getValue() }
 
+  override Type getType() { result = this.getTypeExpr().getResolvedType() }
+
   override string getAPrimaryQlClass() { result = "VarDecl" }
 
-  TypeExpr getType() { toGenerated(result) = var.getChild(0) }
+  TypeExpr getTypeExpr() { toGenerated(result) = var.getChild(0) }
 
   predicate isPrivate() {
     exists(Generated::ClassMember member |
@@ -324,7 +331,7 @@ class VarDecl extends TVarDecl, VarDef {
   override AstNode getAChild(string pred) {
     result = super.getAChild(pred)
     or
-    pred = directMember("getType") and result = this.getType()
+    pred = directMember("getTypeExpr") and result = this.getTypeExpr()
   }
 }
 
@@ -588,11 +595,17 @@ class NewTypeBranch extends TNewTypeBranch, TypeDeclaration {
   }
 }
 
-class Call extends TCall, AstNode {
+class Call extends TCall, Expr {
   Expr getArgument(int i) {
     none() // overriden in sublcasses.
   }
 
+  Predicate getTarget() { resolveCall(this, result) }
+
+  override Type getType() { result = this.getTarget().getReturnType() }
+
+  final int getNumberOfArguments() { result = count(this.getArgument(_)) }
+
   ModuleExpr getQualifier() { none() }
 }
 
@@ -677,6 +690,8 @@ class NoneCall extends TNoneCall, Call, Formula {
   NoneCall() { this = TNoneCall(call) }
 
   override string getAPrimaryQlClass() { result = "NoneCall" }
+
+  override AstNode getParent() { result = Call.super.getParent() }
 }
 
 class AnyCall extends TAnyCall, Call {
@@ -694,16 +709,18 @@ class InlineCast extends TInlineCast, Expr {
 
   override string getAPrimaryQlClass() { result = "InlineCast" }
 
-  TypeExpr getType() {
+  TypeExpr getTypeExpr() {
     toGenerated(result) = expr.getChild(_).(Generated::QualifiedRhs).getChild(_)
   }
 
+  override Type getType() { result = this.getTypeExpr().getResolvedType() }
+
   Expr getBase() { toGenerated(result) = expr.getChild(0) }
 
   override AstNode getAChild(string pred) {
     result = super.getAChild(pred)
     or
-    pred = directMember("getType") and result = this.getType()
+    pred = directMember("getTypeExpr") and result = this.getTypeExpr()
     or
     pred = directMember("getBase") and result = this.getBase()
   }
@@ -1185,6 +1202,14 @@ class Aggregate extends TAggregate, Expr {
 
   override string getAPrimaryQlClass() { result = "Aggregate[" + kind + "]" }
 
+  override PrimitiveType getType() {
+    kind.regexpMatch("(strict)?count|sum|min|max|rank") and
+    result.getName() = "int"
+    or
+    kind.regexpMatch("(strict)?concat") and
+    result.getName() = "string"
+  }
+
   override AstNode getAChild(string pred) {
     result = super.getAChild(pred)
     or
@@ -1232,6 +1257,8 @@ class AsExpr extends TAsExpr, VarDef, Expr {
 
   final override string getName() { result = this.getAsName() }
 
+  final override Type getType() { result = this.getInnerExpr().getType() }
+
   /**
    * Gets the name the inner expression gets "saved" under.
    * For example this is `bar` in the expression `foo as bar`.
@@ -1274,6 +1301,8 @@ class VarAccess extends Identifier {
 
   override string getName() { result = id.getChild().(Generated::VarName).getChild().getValue() }
 
+  override Type getType() { result = this.getDeclaration().getType() }
+
   override string getAPrimaryQlClass() { result = "VarAccess" }
 }
 
@@ -1288,13 +1317,17 @@ class FieldAccess extends Identifier {
 
   override string getName() { result = id.getChild().(Generated::VarName).getChild().getValue() }
 
+  override Type getType() { result = this.getDeclaration().getType() }
+
   override string getAPrimaryQlClass() { result = "FieldAccess" }
 }
 
 /** An access to `this`. */
 class ThisAccess extends Identifier {
   ThisAccess() { any(Generated::This t).getParent() = id }
 
+  override Type getType() { result = this.getParent+().(Class).getType() }
+
   override string getName() { result = "this" }
 
   override string getAPrimaryQlClass() { result = "ThisAccess" }
@@ -1304,6 +1337,8 @@ class ThisAccess extends Identifier {
 class ResultAccess extends Identifier {
   ResultAccess() { any(Generated::Result r).getParent() = id }
 
+  override Type getType() { result = this.getParent+().(Predicate).getReturnType() }
+
   override string getName() { result = "result" }
 
   override string getAPrimaryQlClass() { result = "ResultAccess" }
@@ -1328,7 +1363,9 @@ class Negation extends TNegation, Formula {
 }
 
 /** An expression, such as `x+4`. */
-class Expr extends TExpr, AstNode { }
+class Expr extends TExpr, AstNode {
+  Type getType() { none() }
+}
 
 class ExprAnnotation extends TExprAnnotation, Expr {
   Generated::ExprAnnotation expr_anno;
@@ -1590,5 +1627,3 @@ class ModuleExpr extends TModuleExpr, ModuleRef {
     pred = directMember("getQualifier") and result = this.getQualifier()
   }
 }
-
-private AstNode noParent() { not exists(result.getParent()) and not result instanceof TopLevel }

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

@@ -38,15 +38,59 @@ predicate resolvePredicateExpr(PredicateExpr pe, ClasslessPredicate p) {
   )
 }
 
+private predicate resolvePredicateCall(PredicateCall pc, Predicate p) {
+  exists(Class c, ClassType t |
+    c = pc.getParent*() and
+    t = c.getType() and
+    p = t.getClassPredicate(pc.getPredicateName(), pc.getNumberOfArguments())
+  )
+  or
+  exists(FileOrModule m, boolean public |
+    not exists(pc.getQualifier()) and
+    m = getEnclosingModule(pc).getEnclosing*() and
+    public = [false, true]
+    or
+    m = pc.getQualifier().getResolvedModule() and
+    public = true
+  |
+    definesPredicate(m, pc.getPredicateName(), p, public) and
+    count(p.getParameter(_)) = pc.getNumberOfArguments()
+  )
+}
+
+private predicate resolveMemberCall(MemberCall mc, Predicate p) {
+  exists(ClassType t |
+    t = mc.getBase().getType() and
+    p = t.getClassPredicate(mc.getMemberName(), mc.getNumberOfArguments())
+  )
+}
+
+predicate resolveCall(Call c, Predicate p) {
+  resolvePredicateCall(c, p)
+  or
+  resolveMemberCall(c, p)
+}
+
 module PredConsistency {
   query predicate noResolvePredicateExpr(PredicateExpr pe) {
     not resolvePredicateExpr(pe, _) and
     not pe.getLocation().getFile().getAbsolutePath().regexpMatch(".*/(test|examples)/.*")
   }
 
+  query predicate noResolveCall(Call c) {
+    not resolveCall(c, _) and
+    not c.getLocation().getFile().getAbsolutePath().regexpMatch(".*/(test|examples)/.*")
+  }
+
   query predicate multipleResolvePredicateExpr(PredicateExpr pe, int c, ClasslessPredicate p) {
     c = strictcount(ClasslessPredicate p0 | resolvePredicateExpr(pe, p0)) and
     c > 1 and
     resolvePredicateExpr(pe, p)
   }
+
+  query predicate multipleResolveCall(Call call, int c, Predicate p) {
+    c = strictcount(Predicate p0 | resolveCall(call, p0)) and
+    c > 1 and
+    resolveCall(call, p)
+  }
 }

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

@@ -314,4 +314,18 @@ module TyConsistency {
     c > 1 and
     resolveTypeExpr(te, t)
   }
+
+  query predicate varDefNoType(VarDef def) {
+    not exists(def.getType()) and
+    not def.getLocation().getFile().getAbsolutePath().regexpMatch(".*/(test|examples)/.*")
+  }
+
+  query predicate exprNoType(Expr e) {
+    not exists(e.getType()) and
+    not exists(Predicate p |
+      p = e.(Call).getTarget() and
+      not exists(p.getReturnType())
+    ) and
+    not e.getLocation().getFile().getAbsolutePath().regexpMatch(".*/(test|examples)/.*")
+  }
 }

ql/src/ide-contextual-queries/Definitions.qll

@@ -48,6 +48,11 @@ private predicate resolveVar(VarAccess va, VarDecl decl, string kind) {
   kind = "variable"
 }
 
+private predicate resolveCall(Call c, Predicate p, string kind) {
+  p = c.getTarget() and
+  kind = "call"
+}
+
 cached
 predicate resolve(Loc ref, Loc target, string kind) {
   resolveModule(ref.asAst(), target.asMod(), kind)
@@ -57,4 +62,6 @@ predicate resolve(Loc ref, Loc target, string kind) {
   resolvePredicate(ref.asAst(), target.asAst(), kind)
   or
   resolveVar(ref.asAst(), target.asAst(), kind)
+  or
+  resolveCall(ref.asAst(), target.asAst(), kind)
 }