Добавлены тесты

pkg/expr/expr_test.go

@@ -39,7 +39,15 @@ func TestIsExpression(t *testing.T) {
 		{"time", fmt.Sprintf("d > Time.Time('%s')", now.Format(time.RFC3339)), true},
 		{"in", "In(s, [1,2,3])", true},
 		{"in", "In(s, 1)", true},
-		{"exists", "exists(s)", true},
+		{"exists#1", "exists(s)", true},
+		{"exists#2", "exists", false},
+		{"len#1", "len(s) == 1", true},
+		{"len#2", "len(s) != 1", true},
+		{"len#3", "len(s) > 1", true},
+		{"len#4", "len(s) >= 1", true},
+		{"len#5", "len(s) < 1", true},
+		{"len#6", "len(s) <= 1", true},
+		{"len#7", "len", false},
 		{"text search or id", "id", false},
 		{"numbers", "3", false},
 	}

pkg/expr/mongo.go

@@ -410,10 +410,10 @@ func (c *compiler) CallNode(node *ast.CallNode) interface{} {
 
 		return bson.M{fields: bson.M{"$in": array}}
 	case "exists":
-		field := c.identifier(node.Arguments[0])
-		if field == "" {
-			panic("incorrect argument, empty field name")
+		if len(node.Arguments) != 1 {
+			panic("exists() expects exactly 1 argument")
 		}
+		field := c.identifier(node.Arguments[0])
 		return bson.M{"$or": bson.A{
 			bson.M{field: bson.M{"$exists": true, "$type": "array"}},
 			bson.M{field: bson.M{"$ne": nil}},

pkg/expr/mongo_test.go

@@ -30,12 +30,25 @@ func TestConvertToMongo(t *testing.T) {
 		{"equal", "s == 3", nil, bson.M{"s": 3}, false},
 		{"in array", "s in [1,2,3]", nil, bson.M{"s": bson.M{"$in": []interface{}{1, 2, 3}}}, false},
 		{"not in array", "s not in [1,2,3]", nil, bson.M{"s": bson.M{"$nin": []interface{}{1, 2, 3}}}, false},
-		{"exists", "exists(s)", nil, bson.M{"$or": bson.A{bson.M{"s": bson.M{"$exists": true, "$type": "array"}}, bson.M{"s": bson.M{"$ne": nil}}}}, false},
-		{"len equal", "len(s) == 1", nil, bson.M{"s": bson.M{"$size": 1}}, false},
-		{"len equal empty", "len(s) == 0", nil, bson.M{"s": bson.M{"$eq": bson.A{}}}, false},
+		{"exists#1", "exists(s)", nil, bson.M{"$or": bson.A{bson.M{"s": bson.M{"$exists": true, "$type": "array"}}, bson.M{"s": bson.M{"$ne": nil}}}}, false},
+		{"exists#2", "exists(s, s)", nil, nil, true},
+		{"len#1", "len(s)", nil, nil, true},
+		{"len#2", "len(s) <> 1", nil, nil, true},
+		{"len#3", "len(s) == -1", nil, nil, true},
+		{"len#4", "len(s, s) == -1", nil, nil, true},
+		{"len#5", "len(s) == s", nil, nil, true},
+		{"len eq", "len(s) == 1", nil, bson.M{"s": bson.M{"$size": 1}}, false},
+		{"len eq zero", "len(s) == 0", nil, bson.M{"s": bson.M{"$eq": bson.A{}}}, false},
+		{"len ne", "len(s) != 1", nil, bson.M{"s": bson.M{"$not": bson.M{"$size": 1}}}, false},
+		{"len ne zero", "len(s) != 0", nil, bson.M{"s": bson.M{"$exists": true, "$ne": bson.A{}, "$type": "array"}}, false},
 		{"len gt", "len(s) > 1", nil, bson.M{"s.1": bson.M{"$exists": true}}, false},
-		{"len gt 0", "len(s) > 0", nil, bson.M{"s": bson.M{"$exists": true, "$type": "array", "$ne": bson.A{}}}, false},
+		{"len gt zero", "len(s) > 0", nil, bson.M{"s": bson.M{"$exists": true, "$type": "array", "$ne": bson.A{}}}, false},
+		{"len gte", "len(s) >= 1", nil, bson.M{"s.0": bson.M{"$exists": true}}, false},
+		{"len gte zero", "len(s) >= 0", nil, bson.M{"s": bson.M{"$exists": true, "$type": "array"}}, false},
 		{"len lt", "len(s) < 1", nil, bson.M{"s.0": bson.M{"$exists": false}}, false},
+		{"len lt zero", "len(s) < 0", nil, nil, true},
+		{"len lte", "len(s) <= 1", nil, bson.M{"s.1": bson.M{"$exists": false}}, false},
+		{"len lte zero", "len(s) <= 0", nil, bson.M{"s.0": bson.M{"$exists": false}}, false},
 		{"field#1", "s.test > 3", nil, bson.M{"s.test": bson.M{"$gt": 3}}, false},
 		{"field#2", "s['test'] > 3", nil, bson.M{"s.test": bson.M{"$gt": 3}}, false},
 		{"field#3", "s[test] > 3", nil, bson.M{"s.test": bson.M{"$gt": 3}}, false},