main: add cli flag to load specified account(s)

Make it possible to specify which account(s) to load. Preserve listed
order when creating account tabs.

	aerc -a <account-name[,account-name]>

Signed-off-by: Tim Culverhouse <tim@timculverhouse.com>
Acked-by: Robin Jarry <robin@jarry.cc>

aerc.go

@@ -105,7 +105,7 @@ func buildInfo() string {
 
 func usage(msg string) {
 	fmt.Fprintln(os.Stderr, msg)
-	fmt.Fprintln(os.Stderr, "usage: aerc [-v] [mailto:...]")
+	fmt.Fprintln(os.Stderr, "usage: aerc [-v] [-a <account-name>] [mailto:...]")
 	os.Exit(1)
 }
 
@@ -132,17 +132,21 @@ func setWindowTitle() {
 
 func main() {
 	defer logging.PanicHandler()
-	opts, optind, err := getopt.Getopts(os.Args, "v")
+	opts, optind, err := getopt.Getopts(os.Args, "va:")
 	if err != nil {
 		usage("error: " + err.Error())
 		return
 	}
 	logging.BuildInfo = buildInfo()
+	var accts []string
 	for _, opt := range opts {
 		if opt.Option == 'v' {
 			fmt.Println("aerc " + logging.BuildInfo)
 			return
 		}
+		if opt.Option == 'a' {
+			accts = strings.Split(opt.Value, ",")
+		}
 	}
 	retryExec := false
 	args := os.Args[optind:]
@@ -165,7 +169,7 @@ func main() {
 	}
 	logging.Infof("Starting up version %s", logging.BuildInfo)
 
-	conf, err := config.LoadConfigFromFile(nil)
+	conf, err := config.LoadConfigFromFile(nil, accts)
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "Failed to load config: %v\n", err)
 		os.Exit(1) //nolint:gocritic // PanicHandler does not need to run as it's not a panic

config/config.go

@@ -266,7 +266,7 @@ func mapName(raw string) string {
 	return string(newstr)
 }
 
-func loadAccountConfig(path string) ([]AccountConfig, error) {
+func loadAccountConfig(path string, accts []string) ([]AccountConfig, error) {
 	file, err := ini.Load(path)
 	if err != nil {
 		// No config triggers account configuration wizard
@@ -279,6 +279,9 @@ func loadAccountConfig(path string) ([]AccountConfig, error) {
 		if _sec == "DEFAULT" {
 			continue
 		}
+		if len(accts) > 0 && !contains(accts, _sec) {
+			continue
+		}
 		sec := file.Section(_sec)
 		sourceRemoteConfig := RemoteConfig{}
 		account := AccountConfig{
@@ -355,6 +358,16 @@ func loadAccountConfig(path string) ([]AccountConfig, error) {
 
 		accounts = append(accounts, account)
 	}
+	if len(accts) > 0 {
+		// Sort accounts struct to match the specified order, if we
+		// have one
+		if len(accounts) != len(accts) {
+			return nil, errors.New("account(s) not found")
+		}
+		sort.Slice(accounts, func(i, j int) bool {
+			return accts[i] < accts[j]
+		})
+	}
 	return accounts, nil
 }
 
@@ -663,7 +676,7 @@ func validatePgpProvider(section *ini.Section) error {
 	return nil
 }
 
-func LoadConfigFromFile(root *string) (*AercConfig, error) {
+func LoadConfigFromFile(root *string, accts []string) (*AercConfig, error) {
 	if root == nil {
 		_root := path.Join(xdg.ConfigHome(), "aerc")
 		root = &_root
@@ -823,7 +836,7 @@ func LoadConfigFromFile(root *string) (*AercConfig, error) {
 
 	accountsPath := path.Join(*root, "accounts.conf")
 	logging.Infof("Parsing accounts configuration from %s", accountsPath)
-	if accounts, err := loadAccountConfig(accountsPath); err != nil {
+	if accounts, err := loadAccountConfig(accountsPath, accts); err != nil {
 		return nil, err
 	} else {
 		config.Accounts = accounts
@@ -1089,3 +1102,12 @@ func (uiConfig UIConfig) GetComposedStyle(base StyleObject,
 func (uiConfig UIConfig) GetComposedStyleSelected(base StyleObject, styles []StyleObject) tcell.Style {
 	return uiConfig.style.ComposeSelected(base, styles)
 }
+
+func contains(list []string, v string) bool {
+	for _, item := range list {
+		if item == v {
+			return true
+		}
+	}
+	return false
+}

doc/aerc.1.scd

@@ -6,7 +6,7 @@ aerc - the world's best email client
 
 # SYNOPSIS
 
-_aerc_ [-v] [mailto:...]
+_aerc_ [-v] [-a <account-name[,account-name]>] [mailto:...] 
 
 For a guided tutorial, use *:help tutorial* from aerc, or *man aerc-tutorial*
 from your terminal.
@@ -16,6 +16,11 @@ from your terminal.
 *-v*
 	Prints the installed version of aerc and exits.
 
+*-a <account-name[,account-name]>*
+	Load only the named accounts, as opposed to all configured accounts.
+	List must be comma separated, with no spaces. The account order will be
+	preserved.
+
 *mailto:address[,address][?query[&query]]*
 	Opens the composer with the address(es) in the "to" field. These
 	addresses must not be percent encoded.
@@ -40,7 +45,6 @@ from your terminal.
 
 	Note that reserved characters in the queries must be percent encoded.
 
-
 # RUNTIME COMMANDS
 
 To execute a command, press ':' to bring up the command interface. Commands may