Add support for overriding template dir (#50)

Add optional '-template-dir' flag to 'gotestfmt' cli command that allows overriding of the default template lookup path. Defaults to './.gotestfmt' to maintain backwards compatability.
Simplify ciEnvironments mapping to easier support dynamic root template folder.
Update 'findTemplate' function to allow passing in a root directory path that is used for os filesystem lookups, but not for embed fs lookups.

Co-authored-by: Michael Engel <[email protected]>

cmd/gotestfmt/main.go

@@ -12,19 +12,10 @@ import (
 )
 
 // ciEnvironments maps environment variables to directories to check for templates.
-var ciEnvironments = map[string][]string{
-	"GITHUB_WORKFLOW": {
-		"./.gotestfmt/github",
-		"./.gotestfmt",
-	},
-	"TEAMCITY_VERSION": {
-		"./.gotestfmt/teamcity",
-		"./.gotestfmt",
-	},
-	"GITLAB_CI": {
-		"./.gotestfmt/gitlab",
-		"./.gotestfmt",
-	},
+var ciEnvironments = map[string]string{
+	"GITHUB_WORKFLOW":  "github",
+	"TEAMCITY_VERSION": "teamcity",
+	"GITLAB_CI":        "gitlab",
 }
 
 type hide string
@@ -90,13 +81,12 @@ func hideDescription() string {
 }
 
 func main() {
-	dirs := []string{
-		"./.gotestfmt",
-	}
+	dirs := []string{""}
 	ci := ""
 	inputFile := "-"
 	formatter := ""
 	hide := ""
+	templateDir := "./.gotestfmt"
 	var nofail bool
 	var showTestStatus bool
 
@@ -130,6 +120,12 @@ func main() {
 		formatter,
 		"Absolute path to an external program to format individual test output. This program will be called for each test case with a non-empty output and receive the test case output on stdin. It must produce the final output on stdout.",
 	)
+	flag.StringVar(
+		&templateDir,
+		"template-dir",
+		templateDir,
+		"Absolute path to a folder containing templates",
+	)
 	flag.BoolVar(
 		&nofail,
 		"nofail",
@@ -140,13 +136,16 @@ func main() {
 
 	if ci != "" {
 		dirs = []string{
-			fmt.Sprintf("./.gotestfmt/%s", filepath.Clean(ci)),
-			"./.gotestfmt",
+			filepath.Clean(ci),
+			"",
 		}
 	} else {
-		for env, directories := range ciEnvironments {
+		for env, subDir := range ciEnvironments {
 			if os.Getenv(env) != "" {
-				dirs = directories
+				dirs = []string{
+					subDir,
+					"",
+				}
 			}
 		}
 	}
@@ -160,6 +159,7 @@ func main() {
 	cfg.Formatter = formatter
 
 	format, err := gotestfmt.New(
+		templateDir,
 		dirs,
 	)
 	if err != nil {

gotestfmt.go

@@ -17,29 +17,30 @@ import (
 var fs embed.FS
 
 func New(
+	templateRoot string,
 	templateDirs []string,
 ) (CombinedExitCode, error) {
-	downloadsTpl := findTemplate(templateDirs, "downloads.gotpl")
+	downloadsTpl := findTemplate(templateRoot, templateDirs, "downloads.gotpl")
 
-	packageTpl := findTemplate(templateDirs, "package.gotpl")
+	packageTpl := findTemplate(templateRoot, templateDirs, "package.gotpl")
 
 	return &goTestFmt{
 		downloadsTpl: downloadsTpl,
 		packageTpl:   packageTpl,
 	}, nil
 }
 
-func findTemplate(dirs []string, tpl string) []byte {
+func findTemplate(root string, dirs []string, tpl string) []byte {
 	var lastError error
 	for _, dir := range dirs {
-		templateContents, err := os.ReadFile(path.Join(dir, tpl))
+		templateContents, err := os.ReadFile(path.Join(root, dir, tpl))
 		if err == nil {
 			return templateContents
 		}
 		lastError = err
 	}
 	for _, dir := range dirs {
-		templateContents, err := fs.ReadFile(path.Join(dir, tpl))
+		templateContents, err := fs.ReadFile(path.Join("./.gotestfmt", dir, tpl))
 		if err == nil {
 			return templateContents
 		}
@@ -49,6 +50,7 @@ func findTemplate(dirs []string, tpl string) []byte {
 }
 
 // Combined is an interface that combines both the classic GoTestFmt interface and the Formatter interface.
+//
 //goland:noinspection GoDeprecation
 type Combined interface {
 	GoTestFmt
@@ -64,6 +66,7 @@ type CombinedExitCode interface {
 // GoTestFmt implements the classic Format instruction. This is no longer in use.
 //
 // Deprecated: please use the Formatter interface instead.
+//
 //goland:noinspection GoDeprecation
 type GoTestFmt interface {
 	Format(input io.Reader, target io.WriteCloser)