Fix golangci-lint warnings (#17598 et al) (#17668)

Backport #17598 
Backport #17606 
Backport #17608 
Backport #17609

- Since https://gitea.com/gitea/test-env/pulls/10 the golangci-lint has been upgraded and is erroring about new warnings in the code, this PR fixes those warnings.

.golangci.yml

@@ -9,7 +9,6 @@ linters:
     - unused
     - structcheck
     - varcheck
-    - golint
     - dupl
     #- gocyclo # The cyclomatic complexety of a lot of functions is too high, we should refactor those another time.
     - gofmt

build.go

@@ -2,7 +2,8 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
-//+build vendor
+//go:build vendor
+// +build vendor
 
 package main
 

build/generate-bindata.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build ignore
 // +build ignore
 
 package main

build/generate-emoji.go

@@ -3,6 +3,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build ignore
 // +build ignore
 
 package main

build/generate-gitignores.go

@@ -1,3 +1,4 @@
+//go:build ignore
 // +build ignore
 
 package main

build/generate-licenses.go

@@ -1,3 +1,4 @@
+//go:build ignore
 // +build ignore
 
 package main

build/gocovmerge.go

@@ -6,6 +6,7 @@
 // gocovmerge takes the results from multiple `go test -coverprofile` runs and
 // merges them into one profile
 
+//go:build ignore
 // +build ignore
 
 package main

cmd/docs.go

@@ -43,7 +43,11 @@ func runDocs(ctx *cli.Context) error {
 		// Clean up markdown. The following bug was fixed in v2, but is present in v1.
 		// It affects markdown output (even though the issue is referring to man pages)
 		// https://github.com/urfave/cli/issues/1040
-		docs = docs[strings.Index(docs, "#"):]
+		firstHashtagIndex := strings.Index(docs, "#")
+
+		if firstHashtagIndex > 0 {
+			docs = docs[firstHashtagIndex:]
+		}
 	}
 
 	out := os.Stdout

cmd/embedded.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build bindata
 // +build bindata
 
 package cmd

cmd/embedded_stub.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build !bindata
 // +build !bindata
 
 package cmd

models/migrations/migrations.go

@@ -7,6 +7,7 @@ package migrations
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"os"
 	"reflect"
@@ -762,8 +763,14 @@ func dropTableColumns(sess *xorm.Session, tableName string, columnNames ...strin
 		}
 		tableSQL := string(res[0]["sql"])
 
+		// Get the string offset for column definitions: `CREATE TABLE ( column-definitions... )`
+		columnDefinitionsIndex := strings.Index(tableSQL, "(")
+		if columnDefinitionsIndex < 0 {
+			return errors.New("couldn't find column definitions")
+		}
+
 		// Separate out the column definitions
-		tableSQL = tableSQL[strings.Index(tableSQL, "("):]
+		tableSQL = tableSQL[columnDefinitionsIndex:]
 
 		// Remove the required columnNames
 		for _, name := range columnNames {

modules/auth/pam/pam.go

@@ -1,3 +1,4 @@
+//go:build pam
 // +build pam
 
 // Copyright 2014 The Gogs Authors. All rights reserved.

modules/auth/pam/pam_stub.go

@@ -1,9 +1,10 @@
-// +build !pam
-
 // Copyright 2014 The Gogs Authors. All rights reserved.
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build !pam
+// +build !pam
+
 package pam
 
 import (

modules/auth/pam/pam_test.go

@@ -1,3 +1,4 @@
+//go:build pam
 // +build pam
 
 // Copyright 2021 The Gitea Authors. All rights reserved.

modules/git/blob_gogit.go

@@ -3,6 +3,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build gogit
 // +build gogit
 
 package git

modules/git/blob_nogogit.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build !gogit
 // +build !gogit
 
 package git

modules/git/command_test.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build race
 // +build race
 
 package git

modules/git/commit_convert_gogit.go

@@ -3,6 +3,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build gogit
 // +build gogit
 
 package git

modules/git/commit_info_gogit.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build gogit
 // +build gogit
 
 package git

modules/git/commit_info_nogogit.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build !gogit
 // +build !gogit
 
 package git

modules/git/last_commit_cache_gogit.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build gogit
 // +build gogit
 
 package git

modules/git/last_commit_cache_nogogit.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build !gogit
 // +build !gogit
 
 package git

modules/git/notes_gogit.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build gogit
 // +build gogit
 
 package git

modules/git/notes_nogogit.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build !gogit
 // +build !gogit
 
 package git

modules/git/parse_gogit.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build gogit
 // +build gogit
 
 package git

modules/git/parse_gogit_test.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build gogit
 // +build gogit
 
 package git

modules/git/parse_nogogit.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build !gogit
 // +build !gogit
 
 package git

modules/git/parse_nogogit_test.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build !gogit
 // +build !gogit
 
 package git

modules/git/pipeline/lfs.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build gogit
 // +build gogit
 
 package pipeline

modules/git/pipeline/lfs_nogogit.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT-style
 // license that can be found in the LICENSE file.
 
+//go:build !gogit
 // +build !gogit
 
 package pipeline