Implement "iequals" operator.

ast/ast.go

@@ -1173,7 +1173,7 @@ func (o *Operation) AsProto() *pb.Expression {
 		OpLessThan, OpGreaterThan, OpLessOrEqual, OpGreaterOrEqual,
 		OpBitOr, OpBitAnd, OpBitXor, OpShiftLeft, OpShiftRight,
 		OpContains, OpIContains, OpStartsWith, OpIStartsWith,
-		OpEndsWith, OpIEndsWith, OpMatches:
+		OpEndsWith, OpIEndsWith, OpMatches, OpIEquals:
 		expr = terms[0]
 		for _, term := range terms[1:] {
 			expr = &pb.Expression{

ast/operations.go

@@ -30,6 +30,7 @@ const (
 	OpIStartsWith    OperatorType = "istartswith"
 	OpEndsWith       OperatorType = "endswith"
 	OpIEndsWith      OperatorType = "iendswith"
+    OpIEquals        OperatorType = "iequals"
 	OpMatches        OperatorType = "matches"
 	// Non public operation types. This are operations that exist in the
 	// protobuf, but are not translated into an Operation node in the AST.
@@ -54,6 +55,7 @@ var OpPrecedence = map[OperatorType]int{
 	OpIStartsWith:    4,
 	OpEndsWith:       4,
 	OpIEndsWith:      4,
+	OpIEquals:        4,
 	OpMatches:        4,
 	OpBitOr:          5,
 	OpBitXor:         6,

ast/serialization.go

@@ -78,6 +78,7 @@ var pbToAst = map[pb.BinaryExpression_Operator]OperatorType{
 	pb.BinaryExpression_ISTARTSWITH: OpIStartsWith,
 	pb.BinaryExpression_ENDSWITH:    OpEndsWith,
 	pb.BinaryExpression_IENDSWITH:   OpIEndsWith,
+	pb.BinaryExpression_IEQUALS:     OpIEquals,
 	pb.BinaryExpression_MATCHES:     OpMatches,
 	// Operations that exist in the protobuf but are not translated to an
 	// operation in the AST.
@@ -110,6 +111,7 @@ var astToPb = map[OperatorType]pb.BinaryExpression_Operator{
 	OpEndsWith:       pb.BinaryExpression_ENDSWITH,
 	OpIEndsWith:      pb.BinaryExpression_IENDSWITH,
 	OpMatches:        pb.BinaryExpression_MATCHES,
+	OpIEquals:        pb.BinaryExpression_IEQUALS,
 }
 
 // createOperationExpression creates an operation given an operator and a list of

gyp_test.go

@@ -297,6 +297,12 @@ rule foo {
   condition:
     "foobar" icontains "foo"
 }
+`,
+	`
+rule foo {
+  condition:
+    "foobar" iequals "foo"
+}
 `,
 	`
 rule foo {

parser/grammar.y

@@ -115,6 +115,7 @@ type stringModifiers struct {
 %token _ISTARTSWITH_
 %token _ENDSWITH_
 %token _IENDSWITH_
+%token _IEQUALS_
 %token _IMPORT_
 %token _TRUE_
 %token _FALSE_
@@ -125,7 +126,7 @@ type stringModifiers struct {
 %left '|'
 %left '^'
 %left '&'
-%left _EQ_ _NEQ_
+%left _EQ_ _NEQ_ _ICONTAINS_ _STARTSWITH_ _ENDSWITH_ _ISTARTSWITH_ _IENDSWITH_ _IEQUALS_ _MATCHES_
 %left _LT_ _LE_ _GT_ _GE_
 %left _SHIFT_LEFT_ _SHIFT_RIGHT_
 %left '+' '-'
@@ -784,6 +785,13 @@ expression
            Operands: []ast.Expression{$1, $3},
          }
        }
+     | primary_expression _IEQUALS_ primary_expression
+       {
+         $$ = &ast.Operation{
+           Operator: ast.OpIEquals,
+           Operands: []ast.Expression{$1, $3},
+         }
+      }
     | _STRING_IDENTIFIER_
       {
         $$ = &ast.StringIdentifier{

parser/lexer.l

@@ -204,6 +204,7 @@ octdigit      [0-7]
 "istartswith"           { return yy.Token(_ISTARTSWITH_); }
 "endswith"              { return yy.Token(_ENDSWITH_);    }
 "iendswith"             { return yy.Token(_IENDSWITH_);   }
+"iequals"               { return yy.Token(_IEQUALS_);     }
 "import"                { return yy.Token(_IMPORT_);      }
 "include"               { return yy.Token(_INCLUDE_);     }