AppSettings::DeriveDisplayOrder not ordering options by defined order.

[Dragonrun1]

Rust Version

rustc 1.19.0-nightly (f4209651e 2017-05-05)

Affected Version of clap

clap 2.24.1

Expected Behavior Summary

Options and flag appear in same order as they are defined.

Actual Behavior Summary

Some options are moved into a seemingly more alphabetical order instead.
Good example the '-d' option is moved before the '-n' option even though they are define in opposite order. Another is '--ini' moves up several places instead of just before the '--r*' ones where it should be so it seems to be effecting both long and short options.

Steps to Reproduce the issue

Download
Run cargo run --bin test -- -h where 'test' is the downloaded code.
Notice things are not in the defined order.

Example output

[kbknapp]

This is because you don't have AppSettings::UnifiedHelpMessage set.

I understand you're using the {unified} in the template. Without getting into the weeds, what happens is clap orders flags and options separately (unless UnifiedHelpMessage is set, in which case it merges them at declaration time). Then when printing the help message, if {unified} is used without having also used UnifiedHelpMessage it will do a "best effort" merge.

I'm going to mark this as a documentation issue, as I should probably mention this edge case explicitly.

[Dragonrun1]

Okay adding the other setting did the trick thanks. Yeah probably a good idea to document it so you don't end up with another bug report down the road from someone else :)