Fix naming longer then 64 chars with dots in table (#5045)

Ensures that foreign key relationships and indexes are given
syntactically valid names when their name length exceeds 64 characters
and they contained dot characters within the name. This is most often
relevant when a Postgres table name is fully qualified by including its schema
as part of its name

schema/naming.go

@@ -3,7 +3,6 @@ package schema
 import (
 	"crypto/sha1"
 	"encoding/hex"
-	"fmt"
 	"regexp"
 	"strings"
 	"unicode/utf8"
@@ -95,7 +94,7 @@ func (ns NamingStrategy) formatName(prefix, table, name string) string {
 		h.Write([]byte(formattedName))
 		bs := h.Sum(nil)
 
-		formattedName = fmt.Sprintf("%v%v%v", prefix, table, name)[0:56] + hex.EncodeToString(bs)[:8]
+		formattedName = formattedName[0:56] + hex.EncodeToString(bs)[:8]
 	}
 	return formattedName
 }

schema/naming_test.go

@@ -193,7 +193,7 @@ func TestFormatNameWithStringLongerThan64Characters(t *testing.T) {
 	ns := NamingStrategy{}
 
 	formattedName := ns.formatName("prefix", "table", "thisIsAVeryVeryVeryVeryVeryVeryVeryVeryVeryLongString")
-	if formattedName != "prefixtablethisIsAVeryVeryVeryVeryVeryVeryVeryVeryVeryLo180f2c67" {
+	if formattedName != "prefix_table_thisIsAVeryVeryVeryVeryVeryVeryVeryVeryVery180f2c67" {
 		t.Errorf("invalid formatted name generated, got %v", formattedName)
 	}
 }

schema/relationship_test.go

@@ -576,3 +576,39 @@ func TestHasManySameForeignKey(t *testing.T) {
 		References: []Reference{{"ID", "User", "UserRefer", "Profile", "", true}},
 	})
 }
+
+type Author struct {
+	gorm.Model
+}
+
+type Book struct {
+	gorm.Model
+	Author   Author
+	AuthorID uint
+}
+
+func (Book) TableName() string {
+	return "my_schema.a_very_very_very_very_very_very_very_very_long_table_name"
+}
+
+func TestParseConstraintNameWithSchemaQualifiedLongTableName(t *testing.T) {
+	s, err := schema.Parse(
+		&Book{},
+		&sync.Map{},
+		schema.NamingStrategy{},
+	)
+	if err != nil {
+		t.Fatalf("Failed to parse schema")
+	}
+
+	expectedConstraintName := "fk_my_schema_a_very_very_very_very_very_very_very_very_l4db13eec"
+	constraint := s.Relationships.Relations["Author"].ParseConstraint()
+
+	if constraint.Name != expectedConstraintName {
+		t.Fatalf(
+			"expected constraint name %s, got %s",
+			expectedConstraintName,
+			constraint.Name,
+		)
+	}
+}