Fix #981: unique tag in embeded structure

[liut]

‌‌In the case where there were many changes in version 1.17 + 1 commit, subsequent versions did not work well with a large number of embeds in my scenario. For this reason, I made minor revisions to make it work. When a unique is detected in the subtable, it is set as the only unique. Generally, Unique tags are not used too much. In my scenario, it just solved the problem.

[j2gg0s]

We hadn’t previously defined the behavior for when embed and Unique appear together, so I’ve created some test cases.

        t.Run("embedWithUnique", func(t *testing.T) {
                type Perms struct {
                        View          bool
                        Create        bool
                        UniqueID      int `bun:",unique"`
                        UniqueGroupID int `bun:",unique:groupa"`
                }

                type Role struct {
                        Foo Perms `bun:"embed:foo_"`
                        Perms
                }

                table := tables.Get(reflect.TypeOf((*Role)(nil)))
                require.Nil(t, table.StructMap["foo"])
                require.Nil(t, table.StructMap["bar"])

                fooView, ok := table.FieldMap["foo_view"]
                require.True(t, ok)
                require.Equal(t, []int{0, 0}, fooView.Index)

                barView, ok := table.FieldMap["view"]
                require.True(t, ok)
                require.Equal(t, []int{1, 0}, barView.Index)

                require.Equal(t, 3, len(table.Unique))
                require.Equal(t, 2, len(table.Unique[""]))
                require.Equal(t, "foo_unique_id", table.Unique[""][0].Name)
                require.Equal(t, "unique_id", table.Unique[""][1].Name)
                require.Equal(t, 1, len(table.Unique["groupa"]))
                require.Equal(t, "unique_group_id", table.Unique["groupa"][0].Name)
                require.Equal(t, 1, len(table.Unique["foo_groupa"]))
                require.Equal(t, "foo_unique_group_id", table.Unique["foo_groupa"][0].Name)
        })