Can't preview commit with PANIC on gitdiff.go:357

[shemgp]

• Gitea version (or commit ref): 1.11.0+dev-301-gdd82e401f
• Git version: 2.11.0
• Operating system: Debian GNU/Linux 9
• Database (use [x]):
  • PostgreSQL
  • MySQL
  • MSSQL
  • SQLite
• Can you reproduce the bug at https://try.gitea.io:
  • Yes (provide example URL): https://try.gitea.io/shemgp-aiias/academic-module/commit/bd7063cc7c04689c4d082183d32a604ed27a24f9
  • No
  • Not relevant
• Log gist:

2019/11/27 01:58:26 ...s/charset/charset.go:121:DetectEncoding() [D] Detected encoding: utf-8 (fast)
2019/11/27 01:58:26 ...les/context/panic.go:35:1() [E] PANIC:: runtime error: index out of range [-1]
	/usr/local/go/src/runtime/panic.go:75 (0x435452)
	/go/src/code.gitea.io/gitea/services/gitdiff/gitdiff.go:357 (0x11e9db3)
	/go/src/code.gitea.io/gitea/services/gitdiff/gitdiff.go:865 (0x11eda36)
	/go/src/code.gitea.io/gitea/services/gitdiff/gitdiff.go:809 (0x11ef1ec)
	/go/src/code.gitea.io/gitea/services/gitdiff/gitdiff.go:949 (0x11ef181)
	/go/src/code.gitea.io/gitea/routers/repo/commit.go:229 (0x12d3eed)
	/usr/local/go/src/reflect/value.go:460 (0x497ae5)
	/usr/local/go/src/reflect/value.go:321 (0x4972a3)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/inject/inject.go:177 (0x9aefa9)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/inject/inject.go:137 (0x9ae959)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/context.go:121 (0x9deaf8)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/context.go:112 (0x10ce30a)
	/go/src/code.gitea.io/gitea/modules/context/repo.go:751 (0x10ce2f3)
	/usr/local/go/src/reflect/value.go:460 (0x497ae5)
	/usr/local/go/src/reflect/value.go:321 (0x4972a3)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/inject/inject.go:177 (0x9aefa9)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/inject/inject.go:137 (0x9ae959)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/context.go:121 (0x9deaf8)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/context.go:112 (0x10ccb4c)
	/go/src/code.gitea.io/gitea/modules/context/repo.go:533 (0x10ccb35)
	/usr/local/go/src/reflect/value.go:460 (0x497ae5)
	/usr/local/go/src/reflect/value.go:321 (0x4972a3)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/inject/inject.go:177 (0x9aefa9)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/inject/inject.go:137 (0x9ae959)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/context.go:121 (0x9deaf8)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/context.go:112 (0x10ca4d1)
	/go/src/code.gitea.io/gitea/modules/context/panic.go:39 (0x10ca4bd)
	/usr/local/go/src/reflect/value.go:460 (0x497ae5)
	/usr/local/go/src/reflect/value.go:321 (0x4972a3)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/inject/inject.go:177 (0x9aefa9)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/inject/inject.go:137 (0x9ae959)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/context.go:121 (0x9deaf8)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/context.go:112 (0xaac295)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/session/session.go:192 (0xaac280)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/context.go:79 (0x9de9a0)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/inject/inject.go:157 (0x9aecb9)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/inject/inject.go:135 (0x9aea48)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/context.go:121 (0x9deaf8)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/context.go:112 (0x9f0199)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/recovery.go:161 (0x9f0187)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/logger.go:40 (0x9e2673)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/inject/inject.go:157 (0x9aecb9)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/inject/inject.go:135 (0x9aea48)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/context.go:121 (0x9deaf8)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/context.go:112 (0x9ef4d0)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/logger.go:52 (0x9ef4bb)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/logger.go:40 (0x9e2673)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/inject/inject.go:157 (0x9aecb9)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/inject/inject.go:135 (0x9aea48)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/context.go:121 (0x9deaf8)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/router.go:187 (0x9f13b6)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/router.go:303 (0x9ead95)
	/go/src/code.gitea.io/gitea/vendor/gitea.com/macaron/macaron/macaron.go:220 (0x9e3a0a)
	/go/src/code.gitea.io/gitea/vendor/github.com/gorilla/context/context.go:141 (0xc4cc8d)
	/usr/local/go/src/net/http/server.go:2007 (0x758973)
	/usr/local/go/src/net/http/server.go:2802 (0x75bdc3)
	/usr/local/go/src/net/http/server.go:1890 (0x757764)
	/usr/local/go/src/runtime/asm_amd64.s:1357 (0x466ec0)

Description

Couldn't view commits with PANIC on services/gitdiff/gitdiff.go:357

Screenshots

Thanks for looking into this.

[guillep2k]

It looks like somehow diffFile.Sections is empty @ 357:

gitea/services/gitdiff/gitdiff.go

Lines 344 to 360 in b50dee5

	// GetTailSection creates a fake DiffLineSection if the last section is not the end of the file
	func (diffFile *DiffFile) GetTailSection(gitRepo *git.Repository, leftCommitID, rightCommitID string) *DiffSection {
	if diffFile.Type != DiffFileChange || diffFile.IsBin || diffFile.IsLFSFile {
	return nil
	}
	leftCommit, err := gitRepo.GetCommit(leftCommitID)
	if err != nil {
	return nil
	}
	rightCommit, err := gitRepo.GetCommit(rightCommitID)
	if err != nil {
	return nil
	}
	lastSection := diffFile.Sections[len(diffFile.Sections)-1]
	lastLine := lastSection.Lines[len(lastSection.Lines)-1]
	leftLineCount := getCommitFileLineCount(leftCommit, diffFile.Name)
	rightLineCount := getCommitFileLineCount(rightCommit, diffFile.Name)

@blueworrybear