Update: add props option to no-self-assign rule (fixes #6718)

[mysticatea]

Fixes #6718.

This PR fixes no-self-assign rule to warn properties.

Also, there is a few refactoring (those commits are separated.). I added a function to get the property name of a MemberExpression node (e.g. a.b and a["b"]) into ast-utils.js because this logic is used in multiple places.

[mention-bot]

@mysticatea, thanks for your PR! By analyzing the annotation information on this pull request, we identified @vitorbal, @lo1tuma and @gyandeeps to be potential reviewers

[eslintbot]

Thanks for the pull request, @mysticatea! I took a look to make sure it's ready for merging and found some changes are needed:

• Pull requests with code require an issue to be mentioned at the end of the commit summary, such as (fixes #1234). Please update the commit summary with an issue (file a new issue if one doesn't already exist).

Can you please update the pull request to address these?

(More information can be found in our pull request guide.)

[mysticatea]

Granted, the 1st commit of this PR does not have (fixes #6718), but 2nd commit has it.

[platinumazure]

Nice test case. I'm wondering, should a().b.c = a().b.c constitute a self-assignment or not? (b.c is at least a constant member expression, but a() could return a different object on each invocation, so probably not?)

[mysticatea]

If an expression includes call expression(s), this rule ignores the expression.
I added a test to make sure.

[eslintbot]

Thanks for the pull request, @mysticatea! I took a look to make sure it's ready for merging and found some changes are needed:

• Pull requests with code require an issue to be mentioned at the end of the commit summary, such as (fixes #1234). Please update the commit summary with an issue (file a new issue if one doesn't already exist).

Can you please update the pull request to address these?

(More information can be found in our pull request guide.)

[mysticatea]

I update this PR by the result of discussion.

This PR adds props option, which checks self-assignments of properties also, to no-self-assign.
This option is off by default.

[gyandeeps]

LGTM, waiting for others to review.

[nzakas]

@mysticatea can you rebase?

[eslintbot]

Thanks for the pull request, @mysticatea! I took a look to make sure it's ready for merging and found some changes are needed:

• Pull requests with code require an issue to be mentioned at the end of the commit summary, such as (fixes #1234). Please update the commit summary with an issue (file a new issue if one doesn't already exist).

Can you please update the pull request to address these?

(More information can be found in our pull request guide.)

[mysticatea]

Done!

(The 2nd commit has (fixes #6718))

[platinumazure]

LGTM, thanks for the contribution @mysticatea!

[nzakas]

Oops, looks like we need another rebase here.

[eslintbot]

Thanks for the pull request, @mysticatea! I took a look to make sure it's ready for merging and found some changes are needed:

• Pull requests with code require an issue to be mentioned at the end of the commit summary, such as (fixes #1234). Please update the commit summary with an issue (file a new issue if one doesn't already exist).

Can you please update the pull request to address these?

(More information can be found in our pull request guide.)

[mysticatea]

I rebased it.