CSV diff: unable to load file from base commit

[otbutz]

Description

Creating a new CSV file as part of a pull request doesn't display the files content in the PRs Files changed tab:

https://try.gitea.io/otbutz99/test/pulls/1/files

The file is valid and renders just fine if viewed directly:

https://try.gitea.io/otbutz99/test/src/commit/988460b06f64270788a9f30ed02947e4ab1e6f5a/SampleCSVFile_11kb.csv

The CSV diff works fine for me if the content of the CSV is just changed in the PR:

https://try.gitea.io/otbutz99/test/pulls/2/files

Gitea Version

1.17.2

Can you reproduce the bug on the Gitea demo site?

Yes

Log Gist

No response

Screenshots

Git Version

No response

Operating System

No response

How are you running Gitea?

Release binary via systemd

Database

PostgreSQL

[KN4CK3R]

That's a regression from #19552. This PR enforces base and head to be valid csv files which is not the case if a csv gets created.

[delvh]

Or deleted?

[KN4CK3R]

That may fail too.

[KN4CK3R]

What #19530 (comment) states is wrong because CreateCsvDiff is intended to handle nil readers. I could revert the other PR but without test case for the other issue there may be a new error.

[otbutz]

That may fail too.

Confirmed: https://try.gitea.io/otbutz99/test/pulls/3/files

[wxiaoguang]

Oh yes, I misunderstood the csvReaderFromCommit and CreateCsvDiff logic at that time. Then the question is whether #19552 really fixed the problem (#19530 (comment) said that the 500 error occurs on deleted files)

---

Update (2023-02-17): #22946, CreateCsvDiff should be able to process the situation when base and head are both nil.

[KN4CK3R]

I will add a new PR with better error handling which should work in these cases.