Add unwind refactoring commands

[rrudakov]

The new commands work the same as in clojure-mode with one improvement (hopefully):

In clojure-mode unwinding form (-> foo bar) would produce (-> (bar foo)), so you need to run unwind command one more time to get rid of threading macro. In clojure-ts-mode it will produce (bar foo) immediately. Because of that I had to adapt tests from clojure-mode a little bit.

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[bbatsov]

Apart from my small inline remarks I can suggest also:

• to add a command that displays the unwound version in a separate buffer (I think this will be useful for debug purposes)
• the inverse command (that convert the normal presentation in a threaded one - I'm guessing that's more common refactoring in practice)

Overall, the PR looks good to me, though.

[rrudakov]

Apart from my small inline remarks I can suggest also:

• to add a command that displays the unwound version in a separate buffer (I think this will be useful for debug purposes)

Could you please suggest a command name for that?

• the inverse command (that convert the normal presentation in a threaded one - I'm guessing that's more common refactoring in practice)

Sure. I'm planning to port refactoring commands from clojure-mode and I'm going from top to bottom one thing at the time (to avoid big PRs). It happens that unwind was first :)

Overall, the PR looks good to me, though.

Thanks! I'll fix all the issues.

[bbatsov]

Could you please suggest a command name for that?

Perhaps something like clojure-ts-show-unwound? Or clojure-ts-unwind-to-buffer? Obviously people can get the same result using cider-macroexpand, but I'm guessing the people who use the refactoring commands in clojure-mode, probably are not heavy CIDER users.

[bbatsov]

Sure. I'm planning to port refactoring commands from clojure-mode and I'm going from top to bottom one thing at the time (to avoid big PRs). It happens that unwind was first :)

I figured something like this was the case. :-)

[rrudakov]

Could you please suggest a command name for that?

Perhaps something like clojure-ts-show-unwound? Or clojure-ts-unwind-to-buffer? Obviously people can get the same result using cider-macroexpand, but I'm guessing the people who use the refactoring commands in clojure-mode, probably are not heavy CIDER users.

After giving it some thoughts, I think it would be better to implement in a separate PR. Ideally this would require defining a new minor mode clojure-ts-popup-buffer-mode, write some functions to setup buffer name, major-mode and bind q to quit-buffer, perform unwind command in a temp buffer and insert the result. @bbatsov maybe you could suggest a better idea?

[bbatsov]

After giving it some thoughts, I think it would be better to implement in a separate PR. Ideally this would require defining a new minor mode clojure-ts-popup-buffer-mode, write some functions to setup buffer name, major-mode and bind q to quit-buffer, perform unwind command in a temp buffer and insert the result. @bbatsov maybe you could suggest a better idea?

No, that's more or less what I normally do in such situations. It's fairly simple and standard - you can use cider-macroexpansion.el as a point of reference. Let's have this as a separate PR.