Why is the user defined time's location nil

Question

I'm using go 1.13 and I have a user defined type of type time.Time, and when creating that value with a given location of UTC, the loc attribute is still nil (having a nil loc causes panics in certain time functions, so this is not acceptable). Playground here.
type CustomTime time.Time

func main() {
    t := CustomTime(time.Date(2020, time.July, 23, 1, 0, 0, 0, time.UTC))
    fmt.Printf("%+v",t) // prints {wall:0 ext:63731062800 loc:<nil>}
}

FYI: background info, I'm using this custom time to implement Scan() for my database handler, and when I compare a custom time value defined above (with nil location to the value from the db (non-nil location), my tests are failing due to the comparison failing. Any help or pointers in the right direction would be greatly appreciated.

poWar · Answer

If you look at the doc, time.Time is of type
type Time struct {
    //...
    wall uint64
    ext  int64
    
    // loc specifies the Location that should be used to
    // determine the minute, hour, month, day, and year
    // that correspond to this Time.
    // The nil location means UTC.
    // All UTC times are represented with loc==nil, never loc==&utcLoc.
    loc *Location
}

nil loc actually means UTC. You can verify the same by printing the equality
fmt.Println(time.UTC == time.Time(t).Location())

// Output: true

You see a nil when you print t because you are literally printing the struct Time without using its default Stringer as you have wrapped it with a Custom Type i.e. CustomTime. Hence the loc field will be nil.
fmt.Printf("%+v", time.Time(t))
// This will print UTC for the location.

If you want to use CustomTime everywhere, instead of creating a type alias you can embed time.Time in a struct so that CustomTime can behave like time.Time
type CustomTime struct {
    time.Time
}

func main() {
    t := CustomTime{time.Date(2020, time.July, 23, 1, 0, 0, 0, time.UTC)}
    fmt.Printf("%+v", t) // Prints: 2020-07-23 01:00:00 +0000 UTC
}

Why is the user defined time's location nil

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