From 8f031cda5f7c9f6158530eb439479a6db8f087e1 Mon Sep 17 00:00:00 2001
From: shati-patel <42641846+shati-patel@users.noreply.github.com>
Date: Thu, 27 May 2021 10:35:38 +0100
Subject: [PATCH] Add more expressions

---
 ql/src/codeql_ql/ast/Ast.qll               | 25 +++++++++++++++++++++-
 ql/src/codeql_ql/ast/internal/AstNodes.qll | 17 +++++++++------
 2 files changed, 35 insertions(+), 7 deletions(-)

diff --git a/ql/src/codeql_ql/ast/Ast.qll b/ql/src/codeql_ql/ast/Ast.qll
index cf5cc90f5db..57a21c940b1 100644
--- a/ql/src/codeql_ql/ast/Ast.qll
+++ b/ql/src/codeql_ql/ast/Ast.qll
@@ -403,6 +403,9 @@ class Disjunction extends TDisjunction, AstNode {
   Formula getAnOperand() { toGenerated(result) in [disj.getLeft(), disj.getRight()] }
 }
 
+/**
+ * A comparison operator, such as `<` or `=`.
+ */
 class ComparisonOp extends TComparisonOp, AstNode {
   Generated::Compop op;
 
@@ -613,7 +616,7 @@ class FunctionSymbol extends string {
   FunctionSymbol() { this = "+" or this = "-" or this = "*" or this = "/" or this = "%" }
 }
 
-/** A binary operation, such as `x+3` or `y/2` */
+/** A binary operation expression, such as `x+3` or `y/2` */
 class BinOpExpr extends TBinOpExpr, Expr { }
 
 class AddExpr extends TAddExpr, BinOpExpr {
@@ -630,6 +633,26 @@ class AddExpr extends TAddExpr, BinOpExpr {
   FunctionSymbol getOperator() { result = addexpr.getChild().getValue() }
 }
 
+/** A unary operation expression, such as `-(x*y)` */
+class UnaryExpr extends TUnaryExpr, Expr {
+  Generated::UnaryExpr unaryexpr;
+
+  UnaryExpr() { this = TUnaryExpr(unaryexpr) }
+
+  Expr getOperand() { toGenerated(result) = unaryexpr.getChild(1) }
+
+  FunctionSymbol getOperator() { result = unaryexpr.getChild(0).toString() }
+}
+
+/** A "don't care" expression, denoted by `_`. */
+class DontCare extends TDontCare, Expr {
+  Generated::Underscore dontcare;
+
+  DontCare() { this = TDontCare(dontcare) }
+
+  override string getAPrimaryQlClass() { result = "DontCare" }
+}
+
 /** A module expression. */
 class ModuleExpr extends TModuleExpr, AstNode {
   Generated::ModuleExpr me;
diff --git a/ql/src/codeql_ql/ast/internal/AstNodes.qll b/ql/src/codeql_ql/ast/internal/AstNodes.qll
index fface5bbd4c..7597bdfafa6 100644
--- a/ql/src/codeql_ql/ast/internal/AstNodes.qll
+++ b/ql/src/codeql_ql/ast/internal/AstNodes.qll
@@ -27,13 +27,15 @@ newtype TAstNode =
   TNegation(Generated::Negation neg) or
   TAddExpr(Generated::AddExpr addexp) or
   TLiteral(Generated::Literal lit) or
+  TUnaryExpr(Generated::UnaryExpr unaryexpr) or
+  TDontCare(Generated::Underscore dontcare) or
   TModuleExpr(Generated::ModuleExpr me)
 
 class TFormula = TDisjunction or TConjunction or TComparisonFormula or TQuantifier or TNegation;
 
 class TBinOpExpr = TAddExpr;
 
-class TExpr = TBinOpExpr or TLiteral or TAggregate or TIdentifier;
+class TExpr = TBinOpExpr or TLiteral or TAggregate or TIdentifier or TUnaryExpr or TDontCare;
 
 Generated::AstNode toGeneratedFormula(AST::AstNode n) {
   n = TConjunction(result) or
@@ -41,12 +43,17 @@ Generated::AstNode toGeneratedFormula(AST::AstNode n) {
   n = TComparisonFormula(result) or
   n = TComparisonOp(result) or
   n = TQuantifier(result) or
-  n = TAggregate(result) or
-  n = TIdentifier(result) or
   n = TNegation(result)
 }
 
-Generated::AstNode toGeneratedExpr(AST::AstNode n) { n = TAddExpr(result) }
+Generated::AstNode toGeneratedExpr(AST::AstNode n) {
+  n = TAddExpr(result) or
+  n = TLiteral(result) or
+  n = TAggregate(result) or
+  n = TIdentifier(result) or
+  n = TUnaryExpr(result) or
+  n = TDontCare(result)
+}
 
 /**
  * Gets the underlying TreeSitter entity for a given AST node.
@@ -78,8 +85,6 @@ Generated::AstNode toGenerated(AST::AstNode n) {
   or
   n = TType(result)
   or
-  n = TLiteral(result)
-  or
   n = TAsExpr(result)
   or
   n = TModuleExpr(result)