improved error messages

cmdtime.go

@@ -1,7 +1,6 @@
 package main
 
 import (
-	"fmt"
 	"os"
 	"time"
 
@@ -12,10 +11,10 @@ func cmdTimeSegment(segment *Segment) {
 	duration, err := time.ParseDuration(os.Getenv("cmdtime"))
 	if err != nil {
 		if shell == "bash" {
-			fmt.Fprintln(os.Stderr, "bronze: The 'cmdtime' module is supported in bash.")
-			os.Exit(1)
+			dief("cmdtime: bash is not supported")
+		} else {
+			dief("cmdtime: invalid $cmdtime: %q", os.Getenv("cmdtime"))
 		}
-		panic(err)
 	}
 
 	threshold, err := time.ParseDuration(os.Getenv("BRONZE_CMDTIME_THRESHOLD"))

init.go

@@ -3,7 +3,6 @@ package main
 //go:generate go-bindata -nocompress init.bash init.zsh init.fish
 
 import (
-	"fmt"
 	"os"
 
 	"github.com/urfave/cli"
@@ -18,7 +17,7 @@ var cmdInit = cli.Command{
 		if err == nil {
 			os.Stdout.Write(script)
 		} else {
-			fmt.Fprintln(os.Stderr, "bronze: Unrecognized shell.")
+			dief("unrecognized shell")
 		}
 		return nil
 	},

main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"fmt"
 	"os"
 	"path/filepath"
 
@@ -26,3 +27,14 @@ func die(err error) {
 		panic(err)
 	}
 }
+
+func dief(format string, args ...interface{}) {
+	fmt.Fprintf(os.Stderr, "bronze: "+format, args...)
+	os.Exit(1)
+}
+
+func dieIf(err error, format string, args ...interface{}) {
+	if err != nil {
+		dief(format, args...)
+	}
+}

modules.go

@@ -1,9 +1,6 @@
 package main
 
 import (
-	"fmt"
-	"os"
-
 	. "github.com/reujab/bronze/types"
 )
 
@@ -28,7 +25,6 @@ func handleModule(module string, segment *Segment, args []string) {
 	case "plugin":
 		pluginSegment(segment, args)
 	default:
-		fmt.Fprintf(os.Stderr, "bronze: Invalid module: %q.\n", module)
-		os.Exit(1)
+		dief("invalid module: %q", module)
 	}
 }

packages.go

@@ -11,7 +11,7 @@ import (
 
 func packagesSegment(segment *Segment) {
 	conn, err := net.Dial("unix", "/tmp/packagesd.sock")
-	die(err)
+	dieIf(err, "failed to connect to packagesd socket")
 	defer func() { die(conn.Close()) }()
 
 	packages, err := ioutil.ReadAll(conn)

plugin.go

@@ -1,23 +1,21 @@
 package main
 
 import (
-	"fmt"
-	"os"
+	"path/filepath"
 	"plugin"
 
 	. "github.com/reujab/bronze/types"
 )
 
 func pluginSegment(segment *Segment, args []string) {
 	if len(args) == 0 {
-		fmt.Fprintln(os.Stderr, "bronze: plugin: Expected at least one argument.")
-		os.Exit(1)
+		dief("plugin: expected at least one argument")
 	}
 
 	plug, err := plugin.Open(args[0])
-	die(err)
+	dieIf(err, "plugin: failed to open plugin: %q", args[0])
 
 	handler, err := plug.Lookup("Main")
-	die(err)
+	dieIf(err, "plugin: failed to lookup Main symbol in %q", filepath.Base(args[0]))
 	handler.(func(*Segment, []string))(segment, args[1:])
 }

print.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"fmt"
-	"os"
 	"strings"
 	"sync"
 
@@ -34,8 +33,7 @@ func cmdPrintAction(args []string) {
 		// validate argument
 		fields := strings.Split(arg, ":")
 		if len(fields) < 3 {
-			fmt.Fprintf(os.Stderr, "bronze: Invalid argument: %q. At least three fields expected.\n", arg)
-			os.Exit(1)
+			dief("invalid argument: %q, at least three fields expected", arg)
 		}
 
 		segment := &Segment{

sh.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"fmt"
-	"os"
 )
 
 var colors = map[string]string{
@@ -32,15 +31,13 @@ func escapeBackground(color string) string {
 	case "bash":
 		code, ok := colors["bg-"+color]
 		if !ok {
-			fmt.Fprintf(os.Stderr, "bronze: Invalid background color: %q.", color)
-			os.Exit(1)
+			dief("invalid background color: %q", color)
 		}
 		return "\\[\x1b[" + code + "m\\]"
 	default:
 		code, ok := colors["bg-"+color]
 		if !ok {
-			fmt.Fprintf(os.Stderr, "bronze: Invalid background color: %q.", color)
-			os.Exit(1)
+			dief("invalid background color: %q", color)
 		}
 		return "\x1b[" + code + "m"
 	}
@@ -53,15 +50,13 @@ func escapeForeground(color string) string {
 	case "bash":
 		code, ok := colors["fg-"+color]
 		if !ok {
-			fmt.Fprintf(os.Stderr, "bronze: Invalid foreground color: %q.", color)
-			os.Exit(1)
+			dief("invalid background color: %q", color)
 		}
 		return "\\[\x1b[" + code + "m\\]"
 	default:
 		code, ok := colors["fg-"+color]
 		if !ok {
-			fmt.Fprintf(os.Stderr, "bronze: Invalid foreground color: %q.", color)
-			os.Exit(1)
+			dief("invalid background color: %q", color)
 		}
 		return "\x1b[" + code + "m"
 	}