refactor: code cleanup across codebase (#947)

## Summary

- Extract duplicate \`getReleaseByTag\` into shared \`cmd/releases/utils.go\`
- Replace \`log.Fatal\` calls with proper error returns in config and login commands; \`GetLoginByToken\`/\`GetLoginsByHost\`/\`GetLoginByHost\` now return errors
- Remove dead \`portChan\` channel in \`modules/auth/oauth.go\`
- Fix YAML integer detection to use \`strconv.ParseInt\` (correctly handles negatives and large ints)
- Fix \`path.go\` error handling to use \`errors.As\` + \`syscall.ENOTDIR\` instead of string comparison
- Extract repeated credential helper key into local variable in \`SetupHelper\`
- Use existing \`isRemoteDeleted()\` in \`pull_clean.go\` instead of duplicating the logic
- Fix ~30 error message casing violations to follow Go conventions
- Use \`fmt.Errorf\` consistently instead of string concatenation in \`generic.go\`

Reviewed-on: https://gitea.com/gitea/tea/pulls/947
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
Reviewed-by: Bo-Yi Wu (吳柏毅) <appleboy.tw@gmail.com>
Co-authored-by: Nicolas <bircni@icloud.com>
Co-committed-by: Nicolas <bircni@icloud.com>

modules/task/issue_create.go

@@ -15,7 +15,7 @@ import (
 func CreateIssue(login *config.Login, repoOwner, repoName string, opts gitea.CreateIssueOption) error {
 	// title is required
 	if len(opts.Title) == 0 {
-		return fmt.Errorf("Title is required")
+		return fmt.Errorf("title is required")
 	}
 
 	issue, _, err := login.Client().CreateIssue(repoOwner, repoName, opts)

modules/task/login_create.go

@@ -20,12 +20,13 @@ import (
 func SetupHelper(login config.Login) (ok bool, err error) {
 	// Check that the URL is not blank
 	if login.URL == "" {
-		return false, fmt.Errorf("Invalid gitea url")
+		return false, fmt.Errorf("invalid Gitea URL")
 	}
 
 	// get all helper to URL in git config
+	helperKey := fmt.Sprintf("credential.%s.helper", login.URL)
 	var currentHelpers []byte
-	if currentHelpers, err = exec.Command("git", "config", "--global", "--get-all", fmt.Sprintf("credential.%s.helper", login.URL)).Output(); err != nil {
+	if currentHelpers, err = exec.Command("git", "config", "--global", "--get-all", helperKey).Output(); err != nil {
 		currentHelpers = []byte{}
 	}
 
@@ -37,10 +38,10 @@ func SetupHelper(login config.Login) (ok bool, err error) {
 	}
 
 	// Add tea helper
-	if _, err = exec.Command("git", "config", "--global", fmt.Sprintf("credential.%s.helper", login.URL), "").Output(); err != nil {
-		return false, fmt.Errorf("git config --global %s, error: %s", fmt.Sprintf("credential.%s.helper", login.URL), err)
-	} else if _, err = exec.Command("git", "config", "--global", "--add", fmt.Sprintf("credential.%s.helper", login.URL), "!tea login helper").Output(); err != nil {
-		return false, fmt.Errorf("git config --global --add %s %s, error: %s", fmt.Sprintf("credential.%s.helper", login.URL), "!tea login helper", err)
+	if _, err = exec.Command("git", "config", "--global", helperKey, "").Output(); err != nil {
+		return false, fmt.Errorf("git config --global %s, error: %s", helperKey, err)
+	} else if _, err = exec.Command("git", "config", "--global", "--add", helperKey, "!tea login helper").Output(); err != nil {
+		return false, fmt.Errorf("git config --global --add %s %s, error: %s", helperKey, "!tea login helper", err)
 	}
 
 	return true, nil
@@ -62,7 +63,11 @@ func CreateLogin(name, token, user, passwd, otp, scopes, sshKey, giteaURL, sshCe
 	}
 	// ... if we already use this token
 	if shouldCheckTokenUniqueness(token, sshAgent, sshKey, sshCertPrincipal, sshKeyFingerprint) {
-		if login := config.GetLoginByToken(token); login != nil {
+		login, err := config.GetLoginByToken(token)
+		if err != nil {
+			return err
+		}
+		if login != nil {
 			return fmt.Errorf("token already been used, delete login '%s' first", login.Name)
 		}
 	}

modules/task/milestone_create.go

@@ -17,7 +17,7 @@ import (
 func CreateMilestone(login *config.Login, repoOwner, repoName, title, description string, deadline *time.Time, state gitea.StateType) error {
 	// title is required
 	if len(title) == 0 {
-		return fmt.Errorf("Title is required")
+		return fmt.Errorf("title is required")
 	}
 
 	mile, _, err := login.Client().CreateMilestone(repoOwner, repoName, gitea.CreateMilestoneOption{

modules/task/pull_clean.go

@@ -39,7 +39,7 @@ func PullClean(login *config.Login, repoOwner, repoName string, index int64, ign
 
 	// if remote head branch is already deleted, pr.Head.Ref points to "pulls/<idx>/head"
 	remoteBranch := pr.Head.Ref
-	remoteDeleted := remoteBranch == fmt.Sprintf("refs/pull/%d/head", pr.Index)
+	remoteDeleted := isRemoteDeleted(pr)
 	if remoteDeleted {
 		remoteBranch = pr.Head.Name // this still holds the original branch name
 		fmt.Printf("Remote branch '%s' already deleted.\n", remoteBranch)
@@ -62,9 +62,9 @@ func PullClean(login *config.Login, repoOwner, repoName string, index int64, ign
 	}
 	if branch == nil {
 		if ignoreSHA {
-			return fmt.Errorf("Remote branch %s not found in local repo", remoteBranch)
+			return fmt.Errorf("remote branch %s not found in local repo", remoteBranch)
 		}
-		return fmt.Errorf(`Remote branch %s not found in local repo.
+		return fmt.Errorf(`remote branch %s not found in local repo.
 Either you don't track this PR, or the local branch has diverged from the remote.
 If you still want to continue & are sure you don't loose any important commits,
 call me again with the --ignore-sha flag`, remoteBranch)

modules/task/pull_merge.go

@@ -18,7 +18,7 @@ func PullMerge(login *config.Login, repoOwner, repoName string, index int64, opt
 		return err
 	}
 	if !success {
-		return fmt.Errorf("Failed to merge PR. Is it still open?")
+		return fmt.Errorf("failed to merge PR, is it still open?")
 	}
 	return nil
 }