Implement INDEX_OF function

parsers/nosql/nosql.peg

@@ -240,7 +240,7 @@ AndExpression <- ex1:ComparisonExpression ex2:(ws And ws ex:ComparisonExpression
 
 ComparisonExpression <- "(" ws ex:OrExpression ws ")" { return ex, nil }
     / left:SelectItem ws op:ComparisonOperator ws right:SelectItem {
-    return parsers.ComparisonExpression{Left:left,Right:right,Operation:string(op.([]uint8))}, nil
+    return parsers.ComparisonExpression{Left:left,Right:right,Operation:op.(string)}, nil
 } / ex:BooleanLiteral { return ex, nil }
   / ex:SelectItem { return ex, nil }
 
@@ -276,7 +276,7 @@ Or <- "OR"i
 
 OrderBy <- "ORDER"i ws "BY"i
 
-ComparisonOperator <- "=" / "!=" / "<" / "<=" / ">" / ">=" {
+ComparisonOperator <- ("=" / "!=" / "<" / "<=" / ">" / ">=") {
     return string(c.text), nil
 }
 
@@ -332,12 +332,16 @@ ThreeArgumentStringFunctionExpression <- function:ThreeArgumentStringFunction ws
         functionType = parsers.FunctionCallEndsWith
     case "STARTSWITH":
         functionType = parsers.FunctionCallStartsWith
+    case "INDEX_OF":
+        functionType = parsers.FunctionCallIndexOf
     }
 
     return parsers.FunctionCall{Type: functionType, Arguments: []interface{}{ex1, ex2, ignoreCase}}, nil
 }
 
-ThreeArgumentStringFunction <- "CONTAINS"i / "ENDSWITH"i / "STARTSWITH"i
+ThreeArgumentStringFunction <- ("CONTAINS"i / "ENDSWITH"i / "STARTSWITH"i / "INDEX_OF"i) {
+    return string(c.text), nil
+}
 
 IsDefined <- "IS_DEFINED"i ws "(" ws ex:SelectItem ws ")" {
     return parsers.FunctionCall{Type: parsers.FunctionCallIsDefined, Arguments: []interface{}{ex}}, nil

parsers/nosql/nosql_string_functions_test.go

@@ -226,4 +226,42 @@ func Test_Execute_StringFunctions(t *testing.T) {
 			},
 		)
 	})
+
+	t.Run("Should parse function INDEX_OF()", func(t *testing.T) {
+		testQueryParse(
+			t,
+			`SELECT INDEX_OF(c.id, "2", 1) FROM c`,
+			parsers.SelectStmt{
+				SelectItems: []parsers.SelectItem{
+					{
+						Type: parsers.SelectItemTypeFunctionCall,
+						Value: parsers.FunctionCall{
+							Type: parsers.FunctionCallIndexOf,
+							Arguments: []interface{}{
+								parsers.SelectItem{
+									Path: []string{"c", "id"},
+									Type: parsers.SelectItemTypeField,
+								},
+								parsers.SelectItem{
+									Type: parsers.SelectItemTypeConstant,
+									Value: parsers.Constant{
+										Type:  parsers.ConstantTypeString,
+										Value: "2",
+									},
+								},
+								parsers.SelectItem{
+									Type: parsers.SelectItemTypeConstant,
+									Value: parsers.Constant{
+										Type:  parsers.ConstantTypeInteger,
+										Value: 1,
+									},
+								},
+							},
+						},
+					},
+				},
+				Table: parsers.Table{Value: "c"},
+			},
+		)
+	})
 }