idempotent command and code cleanup

[tittoassini]

This should fix #564

The operation to perform is recalculated before being applied.

[Ailrun]

Sorry, it's bit hard to review with all these style changes mixed with logic changes. Could you divide them into separate commits?

[tittoassini]

Sorry, it's bit hard to review with all these style changes mixed with logic changes. Could you divide them into separate commits?

Hi Ailrun, I would like to help but I would not know where to start to separate it in different commits, it's a single file and all changes are closely related.

Maybe it would be simpler to review directly the new code? It's a very short module:
https://github.com/tittoassini/haskell-language-server/blob/idem/plugins/default/src/Ide/Plugin/ModuleName.hs

Apart from the code refactoring (mainly getting rid of dead code and simplifying the 'actions' function to 'action') the main difference is that 'action', that calculates what is to be done, is called every time the codeLens is used by the user, rather than just at CodeLens creation time.

This avoids the problem of the user clicking multiple times on the CodeLens and ending up with multiple inserts of 'module .. where'.

[jneira]

@tittoassini i think @Ailrun was talking about the formatting changes in language pragmas and imports.
As a general rule we like to separate semantic from syntactic pr's. But well, being the original author of the plugin, i think we can be flexible in this case 😄
I am gonna approve it, @Ailrun i will wait yours for merging

[Ailrun]

Could you clean these debug functions? Other than that, looks good.

[tittoassini]

Thanks.

But clean them up in what way exactly?

I could redefine them so that they use the standard logger, as in the previous 'out' function.

Would that be ok?

[Ailrun]

Yes, that and removing the commented one are what I mean.

[tittoassini]

@tittoassini i think @Ailrun was talking about the formatting changes in language pragmas and imports.
As a general rule we like to separate semantic from syntactic pr's. But well, being the original author of the plugin, i think we can be flexible in thos case 😄
I am gonna approve it, @Ailrun i will wait yours for merging

You are right, next time I will try to be more careful.

[tittoassini]

@jneira I see that this branch has been merged, should I then make a different PR for @Ailrun proposed changes to the traceAs function?

[jneira]

@tittoassini oops, sorry i thought @Ailrun gave his ok 😟 too eager to merge to include it in the next release

please do it in a new pr