Fix skipping lint of ESM components preceded by other statements

[js07]

• Updates the logic of determining if a node is "default export"
• Changes rule checks from running on Program AST nodes to on ExportDefaultDeclaration nodes
• Adds test cases to rules.test.js for ESM components with statements before export default declaration
• Refactors rules.test.js

Fixes #5

[dylburger]

@js07 nice!

Could you also help with two related things:

• Could you add a test case with the case that failed (lines above the export default declaration)
• Could you add a GitHub action to run jest on PRs? I've wanted to do that but haven't had the time.

[dylburger]

looks great and tests are running locally for me!

[js07]

😃

For reference, I added test cases for ESM components whose export default declaration was not the first statement in a file, addressing part of this comment.

I think this PR is ready to be merged barring other suggested changes.

[dylburger]

Yes feel free to merge and update the pipedream repo to incorporate the new version.

[dylburger]

Forgot you didn't have write permissions here, so I merged this one and invited you to the repo. I'll also publish the most recent version to npm (another thing we need to automate!)

Let me know if you can merge the GH Actions PR, or if that doesn't work.

[js07]

Merging the GH Actions PR worked for me.