fix: select with alias (#122)

* fix: select with alias "AS"

* chore: add escape unit test

* chore: add cache load test

* chore: move check alias after cache check

* refactor: follow if pattern to reduce return

* fix: update behaviour

* docs: remove unused comments

adapter/sql/builder_test.go

@@ -353,6 +353,16 @@ func TestBuilder_Find_ordinal(t *testing.T) {
 			nil,
 			query.Select("id", "name"),
 		},
+		{
+			"SELECT \"id\" AS \"user_id\",\"name\" FROM \"users\";",
+			nil,
+			query.Select("id as user_id", "name"),
+		},
+		{
+			"SELECT \"id\" AS \"user_id\",\"name\" FROM \"users\";",
+			nil,
+			query.Select("id AS user_id", "name"),
+		},
 		{
 			"SELECT * FROM \"users\" JOIN \"transactions\" ON \"transactions\".\"id\"=\"users\".\"transaction_id\";",
 			nil,
@@ -781,15 +791,15 @@ func TestBuilder_Select(t *testing.T) {
 			fields:   []string{"id", "name"},
 		},
 		{
-			result: "SELECT COUNT(*) AS count",
+			result: "SELECT COUNT(*) AS `count`",
 			fields: []string{"COUNT(*) AS count"},
 		},
 		{
-			result: "SELECT COUNT(`transactions`.*) AS count",
+			result: "SELECT COUNT(`transactions`.*) AS `count`",
 			fields: []string{"COUNT(transactions.*) AS count"},
 		},
 		{
-			result: "SELECT SUM(`transactions`.`total`) AS total",
+			result: "SELECT SUM(`transactions`.`total`) AS `total`",
 			fields: []string{"SUM(transactions.total) AS total"},
 		},
 	}

adapter/sql/util.go

@@ -37,6 +37,8 @@ func Escape(config Config, field string) string {
 
 	if len(field) > 0 && field[0] == UnescapeCharacter {
 		escapedField = field[1:]
+	} else if i := strings.Index(strings.ToLower(field), " as "); i > -1 {
+		escapedField = Escape(config, field[:i]) + " AS " + Escape(config, field[i+4:])
 	} else if start, end := strings.IndexRune(field, '('), strings.IndexRune(field, ')'); start >= 0 && end >= 0 && end > start {
 		escapedField = field[:start+1] + Escape(config, field[start+1:end]) + field[end:]
 	} else if strings.HasSuffix(field, "*") {

adapter/sql/util_test.go

@@ -28,3 +28,45 @@ func TestToInt64(t *testing.T) {
 	assert.Equal(t, int64(1), toInt64(uint16(1)))
 	assert.Equal(t, int64(1), toInt64(uint8(1)))
 }
+
+func TestEscape(t *testing.T) {
+	config := Config{
+		Placeholder: "?",
+		EscapeChar:  "`",
+	}
+
+	tests := []struct {
+		field  string
+		result string
+	}{
+		{
+			field:  "count(*) as count",
+			result: "count(*) AS `count`",
+		},
+		{
+			field:  "user.address as home_address",
+			result: "`user`.`address` AS `home_address`",
+		},
+		{
+			field:  "^FIELD(`gender`, \"male\") AS order",
+			result: "FIELD(`gender`, \"male\") AS order",
+		},
+		{
+			field:  "*",
+			result: "*",
+		},
+		{
+			field:  "user.*",
+			result: "`user`.*",
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.result, func(t *testing.T) {
+			var (
+				result = Escape(config, test.field)
+			)
+
+			assert.Equal(t, test.result, result)
+		})
+	}
+}