Add auto-completion feature

[sh19910711]

Auto Completion on Web Console

This pull request is to add the "Auto-Completion" feature to help typing commands on Web Console. For example, if people type the TAB key when typing the prefix of some commands, then it shows the list of possible commands from the prefix.

Demo

Things have not been done yet

• Testing
• To support methods
  • >> some.foo<TAB>
• To support arguments of methods
  • >> somemethod(foo<TAB>
• To support constant variables
  • >> Some<TAB>
  • >> Some::Thing<TAB>
• To incrementally refine the list of keywords

Let me know if you have another feature idea of the auto-completion feature.

r? @gsamokovarov # Could you please review the current changes? 🙇

Thanks.

[gsamokovarov]

Instead of introducing a condition here, can we save the current selected binding in the session object? That way, we can evaluate code in an evaluator object and inspect the variables with the binding itself.

[sh19910711]

Updated (it's still working in progress).

Currently supported input cases

For now, I have supported below input cases. Any other input case?

>> foo<TAB>
foobar foobaz
>> foo bar<TAB>
barbaz
>> foo.<TAB>
foo.bar foo.baz
>> foo.bar<TAB>
foo.barbaz
>> Foo::<TAB>
Foo::Bar Foo::Baz
>> @foo<TAB>
@foobar @foobaz
>> $foo<TAB>
$foobar $foobaz

r? @gsamokovarov Could you please review the code again? 🙇

Thank you.

[gsamokovarov]

It seems that a Context object is emerging here. Do you wanna move all this code to lib/web_console/context.rb in a WebConsole::Context class. We can feed it the command and have the current global context as state.

[sh19910711]

Do you wanna move all this code to lib/web_console/context.rb in a WebConsole::Context class.

Yeah, I wanna do that. 👍 Could you show some interface you think?

[sh19910711]

I'm thinking about WebConsole::Context as follows:

>> c = Context.new(@current_binding)
>> c.global
>> c.of(obj)

[gsamokovarov]

Something similar, yeah.

[sh19910711]

OK, I will try it

[sh19910711]

Updated:

• Remove "WIP: " from the title of this pull request
• Add the WebConsole::Context class (ref: d42d509)
• Simplify interface of the Autocomplete class (ref: 7356115)

I will enhance around template testing 🙇

[gsamokovarov]

Great! Thanks for the awesome feature, Hiroyuki. 🙇

[gsamokovarov]

We need a unit-test for that class before release. :-)

[gsamokovarov]

Thank you so much @sh19910711! I'll straight on merge this one now and we can work on the remaining features in separate smaller PRs.