refactor: return err instead of panic and use errgroup

1 files changed, 33 insertions, 26 deletions

diff --git a/cmd/gitmal/main.go b/cmd/gitmal/main.go
index 1581819..2207b95 100644
--- a/cmd/gitmal/main.go
+++ b/cmd/gitmal/main.go
@@ -1,6 +1,7 @@
 package main
 
 import (
+	"errors"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -15,6 +16,13 @@ import (
 var flagOutput string
 
 func main() {
+	if err := run(); err != nil {
+		fmt.Fprintln(os.Stderr, "error:", err)
+		os.Exit(1)
+	}
+}
+
+func run() error {
 	flag.StringVar(&flagOutput, "output", "output", "Output directory")
 	flag.Usage = usage
 	flag.Parse()
@@ -25,17 +33,17 @@ func main() {
 		input = args[0]
 	}
 	if len(args) > 1 {
-		panic("Multiple repos not supported yet")
+		return errors.New("multiple repos not supported yet")
 	}
 
 	outputDir, err := filepath.Abs(flagOutput)
 	if err != nil {
-		panic(err)
+		return err
 	}
 
 	absInput, err := filepath.Abs(input)
 	if err != nil {
-		panic(err)
+		return err
 	}
 	input = absInput
 
@@ -44,12 +52,12 @@ func main() {
 
 	branches, err := git.Branches(input)
 	if err != nil {
-		panic(err)
+		return err
 	}
 
 	tags, err := git.Tags(input)
 	if err != nil {
-		panic(err)
+		return err
 	}
 
 	var defaultBranch string
@@ -58,13 +66,11 @@ func main() {
 	} else if generator.ContainsBranch(branches, "main") {
 		defaultBranch = "main"
 	} else {
-		generator.Echo("No default branch found (expected 'main' or 'master').")
-		os.Exit(1)
+		return errors.New("no default branch found (expected 'main' or 'master')")
 	}
 
 	if yes, a, b := generator.HasConflictingBranchNames(branches); yes {
-		generator.Echo(fmt.Sprintf("Conflicting branchs %q and %q, both want to use %q dir name.", a, b, a.DirName()))
-		os.Exit(1)
+		return fmt.Errorf("conflicting branches %q and %q, both want to use %q dir name", a, b, a.DirName())
 	}
 
 	params := generator.Params{
@@ -80,7 +86,7 @@ func main() {
 	for _, branch := range branches {
 		commitsFor[branch], err = git.Commits(branch, params.RepoDir)
 		if err != nil {
-			panic(err)
+			return err
 		}
 
 		for _, commit := range commitsFor[branch] {
@@ -95,7 +101,7 @@ func main() {
 	for _, tag := range tags {
 		commitsForTag, err := git.Commits(git.NewRef(tag.Name), params.RepoDir)
 		if err != nil {
-			panic(err)
+			return err
 		}
 		for _, commit := range commitsForTag {
 			if alreadyExisting, ok := commits[commit.Hash]; ok && !alreadyExisting.Branch.IsEmpty() {
@@ -108,15 +114,15 @@ func main() {
 	generator.Echo(fmt.Sprintf("> %s: %d branches, %d tags, %d commits", params.Name, len(branches), len(tags), len(commits)))
 
 	if err := generator.GenerateCSS(params); err != nil {
-		panic(err)
+		return err
 	}
 
 	if err := generator.GenerateBranches(branches, defaultBranch, params); err != nil {
-		panic(err)
+		return err
 	}
 
 	if err := generator.GenerateBranchesJSON(branches, commitsFor, params); err != nil {
-		panic(err)
+		return err
 	}
 
 	var defaultBranchFiles []git.Blob
@@ -127,7 +133,7 @@ func main() {
 
 		files, err := git.Files(params.Ref, params.RepoDir)
 		if err != nil {
-			panic(err)
+			return err
 		}
 
 		if branch.String() == defaultBranch {
@@ -135,23 +141,23 @@ func main() {
 		}
 
 		if err := generator.GenerateBlobs(files, params); err != nil {
-			panic(err)
+			return err
 		}
 
 		if err := generator.GenerateLists(files, params); err != nil {
-			panic(err)
+			return err
 		}
 
 		if err := generator.GenerateLogForBranch(commitsFor[branch], params); err != nil {
-			panic(err)
+			return err
 		}
 
 		if err := generator.GenerateCommitsJSON(commitsFor[branch], params); err != nil {
-			panic(err)
+			return err
 		}
 
 		if err := generator.GenerateCommitsAtom(commitsFor[branch], params); err != nil {
-			panic(err)
+			return err
 		}
 	}
 
@@ -159,28 +165,29 @@ func main() {
 
 	generator.Echo("> generating commits...")
 	if err := generator.GenerateCommits(commits, params); err != nil {
-		panic(err)
+		return err
 	}
 
 	if err := generator.GenerateTags(tags, params); err != nil {
-		panic(err)
+		return err
 	}
 
 	if err := generator.GenerateTagsAtom(tags, params); err != nil {
-		panic(err)
+		return err
 	}
 
 	if err := generator.GenerateReleasesAtom(tags, params); err != nil {
-		panic(err)
+		return err
 	}
 
 	if len(defaultBranchFiles) == 0 {
-		panic("No files found for default branch")
+		return errors.New("no files found for default branch")
 	}
 	if err := generator.GenerateIndex(defaultBranchFiles, params); err != nil {
-		panic(err)
+		return err
 	}
 
+	return nil
 }
 
 func usage() {