Update error message handling

[SuperQ]

Use Go 1.13 %w error formatting

• Update minimum Go version to 1.13.
• Bump vendoring.
• Update all error format strings to use %w.
• Cleanup consistency of use.
• Cleanup use of errors.New("string" + var) to use fmt.Errorf().

#310

Signed-off-by: Ben Kochie superq@gmail.com

[beorn7]

I guess with go1.16 on the horizon, we can do this now.

[beorn7]

I sense a somewhat inconsistent use of %s vs %q. Before adding a million comments, perhaps you should first tell us what the intention is.

[SuperQ]

Updated with some s/%s/%q.

[beorn7]

So the guideline is to quote if in doubt? I'll make a pass following that guideline.

[beorn7]

OK, I have found a number of more instances that I believe should be %q.

In summary, I wholeheartedly agree that potentially unknown or misformatted strings in the middle of an error message should be quoted. I'm way more relaxed about anything after a colon, after which you only have a blank and then said string. But I can see the argument for using %q there, too, especially if the string might contain line breaks or tabs.

[beorn7]

And to be clear: I have reviewed now with the assumption that we only ever want to use %s on strings where we can be certain they don't contain "weird stuff".

[SuperQ]

@beorn7 Yes, that seems like a reasonable policy, thanks for the great reviewing.

[discordianfish]

Awesome!

[SuperQ]

@beorn7 Ok, I think I've got it cleaned up. PTAL.

[beorn7]

I found a few more. 🦆

[beorn7]

\o/ The world is a better place now!