refactor: reenable prealloc and fix it properly

The `prealloc` linter was properly enabled in the `.golangci.yml`
configuration.

Optimized various parts of the codebase by pre-allocating slices and
utilizing `make` with a capacity when appropriate. This change aimed to
improve performance by reducing the overhead associated with repeated
slice appends.

Author: chmouel

pkg/cli/browser/browser.go

@@ -10,7 +10,7 @@ import (
 func OpenWebBrowser(ctx context.Context, url string) error {
 	var cmd string
 
-	args := []string{}
+	args := make([]string, 0, 1)
 	switch runtime.GOOS {
 	case "windows":
 		cmd = "cmd"

pkg/matcher/annotation_matcher_test.go

@@ -1361,12 +1361,12 @@ func TestMatchPipelinerunAnnotationAndRepositories(t *testing.T) {
 				tt.args.runevent.Request = &info.Request{Header: http.Header{}, Payload: nil}
 			}
 			if len(tt.args.fileChanged) > 0 {
-				commitFiles := []*github.CommitFile{}
-				for _, v := range tt.args.fileChanged {
-					commitFiles = append(commitFiles, &github.CommitFile{
+				commitFiles := make([]*github.CommitFile, len(tt.args.fileChanged))
+				for i, v := range tt.args.fileChanged {
+					commitFiles[i] = &github.CommitFile{
 						Filename: github.Ptr(v.FileName),
 						Status:   github.Ptr(v.Status),
-					})
+					}
 				}
 				if tt.args.runevent.TriggerTarget == "push" {
 					mux.HandleFunc(fmt.Sprintf("/repos/%s/%s/commits/%s",

pkg/pipelineascode/match_test.go

@@ -335,9 +335,9 @@ func TestGetPipelineRunsFromRepo(t *testing.T) {
 			p.eventEmitter = events.NewEventEmitter(stdata.Kube, logger)
 			matchedPRs, err := p.getPipelineRunsFromRepo(ctx, tt.repositories)
 			assert.NilError(t, err)
-			matchedPRNames := []string{}
+			matchedPRNames := make([]string, len(matchedPRs))
 			for i := range matchedPRs {
-				matchedPRNames = append(matchedPRNames, matchedPRs[i].PipelineRun.GetGenerateName())
+				matchedPRNames[i] = matchedPRs[i].PipelineRun.GetGenerateName()
 			}
 			if tt.logSnippet != "" {
 				assert.Assert(t, logCatcher.FilterMessageSnippet(tt.logSnippet).Len() > 0, logCatcher.All())

pkg/provider/gitea/test/setup.go

@@ -52,7 +52,6 @@ func Setup(t *testing.T) (*gitea.Client, *http.ServeMux, func()) {
 
 // SetupGitTree Take a dir and fake a full GitTree Gitea api calls reply recursively over a muxer.
 func SetupGitTree(t *testing.T, mux *http.ServeMux, dir string, event *info.Event, recursive bool) {
-	entries := []gitea.GitEntry{}
 	type file struct {
 		sha, name string
 		isdir     bool
@@ -76,6 +75,7 @@ func SetupGitTree(t *testing.T, mux *http.ServeMux, dir string, event *info.Even
 			files = append(files, file{name: filepath.Join(dir, f.Name()), sha: sha, isdir: f.IsDir()})
 		}
 	}
+	entries := make([]gitea.GitEntry, 0, len(files))
 	for _, f := range files {
 		etype := "blob"
 		mode := "100644"

pkg/secrets/secrets.go

@@ -66,8 +66,8 @@ func GetSecretsAttachedToPipelineRun(ctx context.Context, k kubeinteraction.Inte
 // if we don't sort by longest then if there two passwords with the same prefix
 // the shortest one will replace and would leak the end of the passwords of the longest after.
 func sortSecretsByLongests(values []ktypes.SecretValue) []ktypes.SecretValue {
-	ret := []ktypes.SecretValue{}
-	ret = append(ret, values...)
+	ret := make([]ktypes.SecretValue, len(values))
+	copy(ret, values)
 	for i := 0; i < len(ret); i++ {
 		for j := i + 1; j < len(ret); j++ {
 			if len(ret[i].Value) < len(ret[j].Value) {

pkg/sort/repository_status.go

@@ -29,10 +29,8 @@ func (rs repoSortRunStatus) Less(i, j int) bool {
 }
 
 func RepositorySortRunStatus(repoStatus []v1alpha1.RepositoryRunStatus) []v1alpha1.RepositoryRunStatus {
-	rrstatus := repoSortRunStatus{}
-	for _, status := range repoStatus {
-		rrstatus = append(rrstatus, status)
-	}
+	rrstatus := make(repoSortRunStatus, len(repoStatus))
+	copy(rrstatus, repoStatus)
 	sort.Sort(rrstatus)
 	return rrstatus
 }

pkg/sort/task_log_snippets.go

@@ -19,7 +19,7 @@ func (s taskInfoSorter) Less(i, j int) bool {
 }
 
 func TaskInfos(taskinfos map[string]pacv1alpha1.TaskInfos) []pacv1alpha1.TaskInfos {
-	tis := taskInfoSorter{}
+	tis := make(taskInfoSorter, 0, len(taskinfos))
 	for _, ti := range taskinfos {
 		tis = append(tis, ti)
 	}

pkg/sync/queue_manager.go

@@ -290,15 +290,15 @@ func (qm *QueueManager) RunningPipelineRuns(repo *v1alpha1.Repository) []string
 }
 
 func sortPipelineRunsByCreationTimestamp(prs []tektonv1.PipelineRun) []*tektonv1.PipelineRun {
-	runTimeObj := []runtime.Object{}
+	runTimeObj := make([]runtime.Object, len(prs))
 	for i := range prs {
-		runTimeObj = append(runTimeObj, &prs[i])
+		runTimeObj[i] = &prs[i]
 	}
 	sort.ByField(creationTimestamp, runTimeObj)
-	sortedPRs := []*tektonv1.PipelineRun{}
-	for _, run := range runTimeObj {
+	sortedPRs := make([]*tektonv1.PipelineRun, len(runTimeObj))
+	for i, run := range runTimeObj {
 		pr, _ := run.(*tektonv1.PipelineRun)
-		sortedPRs = append(sortedPRs, pr)
+		sortedPRs[i] = pr
 	}
 	return sortedPRs
 }

pkg/sync/queue_manager_test.go

@@ -329,9 +329,9 @@ func TestFilterPipelineRunByInProgress(t *testing.T) {
 		PipelineRuns: pipelineRuns,
 	}
 
-	orderList := []string{}
-	for _, pr := range pipelineRuns {
-		orderList = append(orderList, fmt.Sprintf("%s/%s", ns, pr.GetName()))
+	orderList := make([]string, len(pipelineRuns))
+	for i, pr := range pipelineRuns {
+		orderList[i] = fmt.Sprintf("%s/%s", ns, pr.GetName())
 	}
 	stdata, _ := testclient.SeedTestData(t, ctx, tdata)
 	filtered := FilterPipelineRunByState(ctx, stdata.Pipeline, orderList, tektonv1.PipelineRunSpecStatusPending, kubeinteraction.StateQueued)

pkg/sync/semaphore.go

@@ -39,15 +39,15 @@ func (s *prioritySemaphore) getLimit() int {
 }
 
 func (s *prioritySemaphore) getCurrentPending() []string {
-	keys := []string{}
+	keys := make([]string, 0, len(s.pending.items))
 	for _, item := range s.pending.items {
 		keys = append(keys, item.key)
 	}
 	return keys
 }
 
 func (s *prioritySemaphore) getCurrentRunning() []string {
-	keys := []string{}
+	keys := make([]string, 0, len(s.running))
 	for k := range s.running {
 		keys = append(keys, k)
 	}