plan for typing of structuredDiffForFile

[berlysia]

The return value of structuredDiffForFile is not well typed. (and I use this heavily)

danger-js/source/danger.d.ts

Lines 809 to 813 in a7355a3

	/** Git diff sliced into chunks */
	interface StructuredDiff {
	/** Git diff chunks */
	chunks: any[]
	}

I did a little research and found that in general case, the parse-diff 's return object is used as is. see. #1089
The case of BitBucketServer is an exception and there seems to be some effort. see. #773

danger-js/source/platforms/bitbucket_server/BitBucketServerGit.ts

Lines 77 to 80 in a7355a3

	getStructuredDiffForFile: async (base: string, head: string, filename: string) => {
	const diff = await bitBucketServerAPI.getStructuredDiffForFile(base, head, filename)
	return bitBucketServerDiffToGitStructuredDiff(diff)
	},

There is some variation of plan, as far as I can think:

A. Create BitBucketServerGitDSL or just like GitDSL<BitBuckerServer> , which have specialized type definition of structredDiffForFile.
B. Add type for general case. BitBucketServer users are required to cast type for their environment.
C. Add type for general case. Modify the implementation for BitBucketServer to fit the general case.
D. Add type as union of general case and specialized case. All user must choice to write type-narrowing code or to ignore types.
E. No change for code. Provide a comment to get well-typed structuredDiffForFile.
F. other

According to #773 , C is the most likely choice but there's still a difference.

How do you think about this?

[orta]

Yeah, I think C makes the most sense 👍🏻

[berlysia]

Great. I made #1201
Would you take a look?

[berlysia]

#1201