Remove legacy git code (ver < 2.0), fine tune markup tests

[wxiaoguang]

Follows #19732 #19577

• Refactor git module, make Gitea use internal git config #19732
• Increase minimal required git version to 2.0 #19577

Close #19874

• Fix all unit tests without git.Init after #19732 merged, clean code for git < 2.0 after #19577 #19874

Major changes:

1. Remove legacy code for git < 2.0
2. Fix a bug in runHookPostReceive, now setup(including git.Init) is called before git.NewCommand
3. Introduce strict mode for git.InitXxx
   • strict mode means that if the git.InitXxx isn't called, then the calls to git.NewCommand will result in error.
   • this mechanism will guarantee that there will be no mistake in the future.
4. Fix the unit test code for markup module
5. Add more comments for git.InitXxx
6. Update document for commit signing, using Gitea's internal git config

Files changed: Diff with whitespace-ignored

[wxiaoguang]

This PR has done what it could do. There is still a remaining problem.(fixed)

To avoid blocking 1.17 release, the remaining problem is recorded in a new issue #19938

• Refactor git.HomeDir to strict mode (report fatal when it's not initialized correctly) #19938

[zeripath]

Hmm... I remember somewhere you commented about CheckLFSVersion causing problems.

I wonder if It could just be folded into the Init function?

[wxiaoguang]

Hmm... I remember somewhere you commented about CheckLFSVersion causing problems.

I wonder if It could just be folded into the Init function?

I have tried but got no success at the moment. Since 1.17 is going to be released, I think the big refactoring could be postponed to next milestone, otherwise there will be a lot of code changed, which may affect the 1.17 milestone.

I think it might be reasonable to refactor this into a function: CheckAttributesFor

Agree it should be refactored. I was thinking about postponing it to next milestone (reason as above). How do you think? I am fine to either plan.

[zeripath]

wxiaoguang#6

[wxiaoguang]

wxiaoguang#6

Merged, thank you very much.

[codecov-commenter]

Codecov Report

Merging #19930 (a8f2999) into main (0097fbc) will decrease coverage by 0.37%.
The diff coverage is 46.21%.

❗ Current head a8f2999 differs from pull request most recent head 8a2b4a8. Consider uploading reports for the commit 8a2b4a8 to get more accurate results

@@            Coverage Diff             @@
##             main   #19930      +/-   ##
==========================================
- Coverage   47.29%   46.91%   -0.38%     
==========================================
  Files         966      967       +1     
  Lines      134117   134087      -30     
==========================================
- Hits        63424    62909     -515     
- Misses      62977    63472     +495     
+ Partials     7716     7706      -10     

Impacted Files	Coverage Δ
cmd/cmd.go	40.74% <0.00%> (ø)
cmd/hook.go	7.11% <0.00%> (ø)
cmd/migrate_storage.go	0.00% <0.00%> (ø)
cmd/serv.go	2.22% <0.00%> (ø)
models/consistency.go	34.78% <ø> (+22.62%)	⬆️
models/db/consistency.go	0.00% <0.00%> (ø)
models/db/list_options.go	63.63% <ø> (ø)
models/error.go	38.66% <ø> (+2.79%)	⬆️
models/git/lfs_lock.go	41.96% <ø> (ø)
models/git/protected_tag.go	67.64% <ø> (ø)
... and 214 more

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[silverwind]

Do we document the min git version somewhere?

[delvh]

@silverwind https://github.com/go-gitea/gitea/pull/19577/files

[lunny]

make L-G-T-M work.