ArgResults should either implement the Map interface or make the options Map accessible

[DartBot]

This issue was originally filed by googlegroups...@kaioa.com

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Right now, the options Map is private. ArgResults defines the [] operator to allow Map-like read-only access.

This works fine. However, you end up passing the ArgResults object around, because pulling the values out of that ArgsResult object is quite a bit of work. This is inconvenient when it comes to testing, because creating an ArgResults object is more work than creating a Map.

Also, this kind of dependency is really weird. Whatever that function does, it probably has very little to do with argument parsing. It shouldn't take an ArgsResult object as argument.

[iposva-google]

Added Area-Pkg, Library-Args, Triaged labels.

[anders-sandholm]

Removed Library-Args label.
Added Pkg-Args label.

[munificent]

I think it would feel weird if ArgResults itself implemented Map. Things like results.values seems odd to me. What might be nice is ArgResults.options was an actual map. Unfortunately, that collides with the current type of .options.

I think what I'd probably like is to change that to a Map. You could then use .options.keys to get the option names. That's a breaking change, though, so I'm going to defer that a bit.

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Set owner to @munificent.
Removed Type-Defect, Priority-Unassigned labels.
Added Type-Enhancement, Priority-Medium labels.

[DartBot]

This issue has been moved to dart-lang/args#21.