MVP lint rules

[bartlomieju]

Decide on list of lint rules that are required for MVP linter.

Good idea to go through recommended sets and compile a list:

• eslint
• typescript-eslint

[lucacasonato]

I think we should start with all of the recommended rules in the possible errors section of eslint. These are lints that prevent runtime errors, so they are most useful. Those would be:

• for-direction
• getter-return
• no-async-promise-executor
• no-compare-neg-zero
• no-cond-assign
• no-constant-condition
• no-control-regex
• no-debugger
• no-dupe-args
• no-dupe-else-if
• no-dupe-keys
• no-duplicate-case
• no-empty
• no-empty-character-class
• no-ex-assign
• no-extra-boolean-cast
• no-extra-semi
• no-func-assign
• no-import-assign
• no-inner-declarations
• no-invalid-regexp
• no-irregular-whitespace
• no-misleading-character-class
• no-obj-calls
• no-prototype-builtins
• no-regex-spaces
• no-setter-return
• no-sparse-arrays
• no-unexpected-multiline
• no-unreachable
• no-unsafe-finally
• no-unsafe-negation
• use-isnan
• valid-typeof

Then later we should implement the possible errors recommended rules for typescript and then the remaining recommended eslint and typescript specific rules. It would be awesome if we could have support for eslint:recommended and @typescript-eslint/recommended out of the box.

Ideas?

[bartlomieju]

I think we should start with all of the recommended rules in the possible errors section of eslint. These are lints that prevent runtime errors, so they are most useful. Those would be:

Then later we should implement the possible errors recommended rules for typescript and then the remaining recommended eslint and typescript specific rules. It would be awesome if we could have support for eslint:recommended and @typescript-eslint/recommended out of the box.

@lucacasonato thanks for compiling the list, presented approach seems to be reasonable.

Keep in mind I'm still iterating heavily on AST traversal and the AstTraverser will most likely be removed altogether in the near future.

[bartlomieju]

Update: AstTraverser was replaced with swc_ecma_visit::Visit trait which serves the same purpose. I'm working on control flow analysis for more complex rules, but a lot of listed rules could now be implemented.

[DomParfitt]

Hi @bartlomieju, are you looking for contributors for any of these rules? If so, I would be happy to have a look at one or more of them.

[bartlomieju]

Hey @DomParfitt; this project hasn't received much attention in the past weeks due to release of Deno. There is still some core infrastructure missing, but if you can find a rule and implement it feel free to open a PR :) Keep in mind that scope analysis is not complete #21

[sgtpep]

How about no-unused-vars?

[bartlomieju]

@sgtpep no-unused-vars requires scope analysis, which is WIP in #21

[bartlomieju]

I've written down list of all recommended rules from ESLint in: #48