feature/count (#34)

* add count

* fix typo

condition/gorm_query.go

@@ -80,6 +80,15 @@ func (query *GormQuery) Limit(limit int) {
 	query.GormDB = query.GormDB.Limit(limit)
 }
 
+// Count returns the amount of models that fulfill the conditions
+func (query *GormQuery) Count() (int64, error) {
+	query.cleanSelects()
+
+	var count int64
+
+	return count, query.GormDB.Count(&count).Error
+}
+
 // First finds the first record ordered by primary key, matching given conditions
 func (query *GormQuery) First(dest any) error {
 	return query.GormDB.First(dest).Error
@@ -243,6 +252,10 @@ func (query *GormQuery) Returning(dest any) error {
 	return nil
 }
 
+func (query *GormQuery) cleanSelects() {
+	query.GormDB.Statement.Selects = []string{}
+}
+
 // Find finds all models matching given conditions
 func (query *GormQuery) Update(sets []ISet) (int64, error) {
 	tablesAndValues, err := getUpdateTablesAndValues(query, sets)
@@ -252,7 +265,7 @@ func (query *GormQuery) Update(sets []ISet) (int64, error) {
 
 	updateMap := map[string]any{}
 
-	query.GormDB.Statement.Selects = []string{}
+	query.cleanSelects()
 
 	switch query.Dialector() {
 	case sql.Postgres, sql.SQLServer, sql.SQLite: // support UPDATE SET FROM

condition/query.go

@@ -59,6 +59,17 @@ func (query *Query[T]) Offset(offset int) *Query[T] {
 	return query
 }
 
+// Finishing methods
+
+// Count returns the amount of models that fulfill the conditions
+func (query *Query[T]) Count() (int64, error) {
+	if query.err != nil {
+		return 0, query.err
+	}
+
+	return query.gormQuery.Count()
+}
+
 // First finds the first model ordered by primary key, matching given conditions
 // or returns gorm.ErrRecordNotFound is if no model does it
 func (query *Query[T]) First() (*T, error) {

docs/cql/query.rst

@@ -40,6 +40,7 @@ Finishing methods
 
 Finishing methods are those that cause the query to be executed and the result(s) of the query to be returned:
 
+- Count: returns the amount of models that fulfill the conditions.
 - First: finds the first model ordered by primary key.
 - Take: finds the first model returned by the database in no specified order.
 - Last: finds the last model ordered by primary key.

test/query_test.go

@@ -25,6 +25,49 @@ func NewQueryIntTestSuite(
 	}
 }
 
+// ------------------------- Count --------------------------------
+
+func (ts *QueryIntTestSuite) TestCountReturns0IfNotModels() {
+	count, err := cql.Query[models.Product](
+		ts.db,
+	).Count()
+
+	ts.Require().NoError(err)
+	ts.Equal(int64(0), count)
+}
+
+func (ts *QueryIntTestSuite) TestCountReturns0IfConditionsDontMatch() {
+	ts.createProduct("", 0, 0, false, nil)
+	count, err := cql.Query[models.Product](
+		ts.db,
+		conditions.Product.Int.Is().Eq(1),
+	).Count()
+
+	ts.Require().NoError(err)
+	ts.Equal(int64(0), count)
+}
+
+func (ts *QueryIntTestSuite) TestCountReturns1IfConditionsMatch() {
+	ts.createProduct("", 1, 0, false, nil)
+	count, err := cql.Query[models.Product](
+		ts.db,
+		conditions.Product.Int.Is().Eq(1),
+	).Count()
+	ts.Require().NoError(err)
+	ts.Equal(int64(1), count)
+}
+
+func (ts *QueryIntTestSuite) TestReturnsNIfMoreThanOneMatchConditions() {
+	ts.createProduct("", 0, 0, false, nil)
+	ts.createProduct("", 0, 0, false, nil)
+	count, err := cql.Query[models.Product](
+		ts.db,
+		conditions.Product.Int.Is().Eq(0),
+	).Count()
+	ts.Require().NoError(err)
+	ts.Equal(int64(2), count)
+}
+
 // ------------------------- FindOne --------------------------------
 
 func (ts *QueryIntTestSuite) TestFindOneReturnsErrorIfConditionsDontMatch() {