Add example to readme

README.md

@@ -31,6 +31,83 @@ The exported package is `errors`, basic usage:
 import "github.com/coditory/go-errors"
 
 func main() {
-  // TBD
+	err := foo()
+	fmt.Printf("\n>>> Format %%s:\n%s", err)
+	fmt.Printf("\n>>> Format %%v:\n%v", err)
+	fmt.Printf("\n>>> Format %%+v:\n%+v", err)
+	fmt.Printf("\n>>> Format %%#v:\n%#v", err)
 }
+
+func foo() error {
+	err := bar()
+	return errors.Wrap(err, "foo failed")
+}
+
+func bar() error {
+	return errors.New("bar failed")
+}
+```
+
+Output for `go run ./samples`
+
+```
+>>> Format %s:
+foo failed
+
+>>> Format %v:
+foo failed
+	main.foo:19
+	main.main:10
+	runtime.main:250
+	runtime.goexit:1598
+caused by: bar failed
+	main.bar:23
+	main.foo:18
+	main.main:10
+	runtime.main:250
+	runtime.goexit:1598
+
+>>> Format %+v:
+foo failed
+	./samples.go:19
+		main.foo
+	./samples.go:10
+		main.main
+	<GO_SRC_DIR>/runtime/proc.go:250
+		runtime.main
+	<GO_SRC_DIR>/runtime/asm_amd64.s:1598
+		runtime.goexit
+caused by: bar failed
+	./samples.go:23
+		main.bar
+	./samples.go:18
+		main.foo
+	./samples.go:10
+		main.main
+	<GO_SRC_DIR>/runtime/proc.go:250
+		runtime.main
+	<GO_SRC_DIR>/runtime/asm_amd64.s:1598
+		runtime.goexit
+
+>>> Format %#v:
+foo failed
+	<PROJECT_DIR>/samples/samples.go:19
+		main.foo
+	<PROJECT_DIR>/samples/samples.go:10
+		main.main
+	<GO_SRC_DIR>/runtime/proc.go:250
+		runtime.main
+	<GO_SRC_DIR>/runtime/asm_amd64.s:1598
+		runtime.goexit
+caused by: bar failed
+	<PROJECT_DIR>/samples/samples.go:23
+		main.bar
+	<PROJECT_DIR>/samples/samples.go:18
+		main.foo
+	/Users/mendlik/Development/go/go-errors/samples/samples.go:10
+		main.main
+	<GO_SRC_DIR>/runtime/proc.go:250
+		runtime.main
+	<GO_SRC_DIR>/runtime/asm_amd64.s:1598
+		runtime.goexit
 ```

errors.go

@@ -48,9 +48,6 @@ type Error struct {
 }
 
 func (e *Error) Error() string {
-	if e.message != "" && e.err != nil {
-		return fmt.Sprintf("%s: %s", e.message, e.err.Error())
-	}
 	if e.message != "" {
 		return e.message
 	}
@@ -71,15 +68,15 @@ func (e *Error) StackTrace() StackTrace {
 func (e *Error) Format(s fmt.State, verb rune) {
 	switch verb {
 	case 'v':
-		e.formatCauses(s, s.Flag('+'))
+		e.formatCauses(s)
 	case 's':
 		write(s, e.Error())
 	case 'q':
 		fmt.Fprintf(s, "%q", e.Error())
 	}
 }
 
-func (e *Error) formatCauses(s fmt.State, plus bool) {
+func (e *Error) formatCauses(s fmt.State) {
 	var err error
 	err = e
 	causes := 0
@@ -99,9 +96,12 @@ func (e *Error) formatCauses(s fmt.State, plus bool) {
 			}
 			for i := 0; i < n; i++ {
 				frame := stacktrace[i]
-				if plus {
+				if s.Flag('+') {
 					fmt.Fprintf(s, "\t%s:%d\n", frame, frame)
 					fmt.Fprintf(s, "\t\t%n\n", frame)
+				} else if s.Flag('#') {
+					fmt.Fprintf(s, "\t%+s:%d\n", frame, frame)
+					fmt.Fprintf(s, "\t\t%+n\n", frame)
 				} else {
 					fmt.Fprintf(s, "\t%n:%d\n", frame, frame)
 				}
@@ -114,10 +114,6 @@ func (e *Error) formatCauses(s fmt.State, plus bool) {
 				}
 			}
 		}
-		if werr, ok := err.(*Error); ok {
-			// deduplicate wrapped error message
-			err = werr.Unwrap()
-		}
 		if werr, ok := err.(wrapper); ok {
 			err = werr.Unwrap()
 		} else {
@@ -298,7 +294,11 @@ func relName(name string) string {
 		if strings.HasPrefix(BasePath, "**/") {
 			i := strings.Index(name, BasePath[3:])
 			if i > 0 {
-				return "./" + name[i+len(BasePath)-2:]
+				name = name[i+len(BasePath)-2:]
+				for strings.HasPrefix(name, BasePath[3:]) {
+					name = name[len(BasePath)-2:]
+				}
+				return "./" + name
 			}
 		} else if strings.HasPrefix(name, BasePath) {
 			return name[len(BasePath)+1:]

samples/samples.go

@@ -0,0 +1,24 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/coditory/go-errors"
+)
+
+func main() {
+	err := foo()
+	fmt.Printf("\n>>> Format %%s:\n%s", err)
+	fmt.Printf("\n>>> Format %%v:\n%v", err)
+	fmt.Printf("\n>>> Format %%+v:\n%+v", err)
+	fmt.Printf("\n>>> Format %%#v:\n%#v", err)
+}
+
+func foo() error {
+	err := bar()
+	return errors.Wrap(err, "foo failed")
+}
+
+func bar() error {
+	return errors.New("bar failed")
+}

test/common_test.go

@@ -0,0 +1,11 @@
+package errors_test
+
+import (
+	"github.com/coditory/go-errors"
+)
+
+func init() {
+	errors.BaseModule = "github.com/coditory/go-errors"
+	errors.BasePath = "**/go-errors"
+	errors.BaseCachePath = "**/mod/pkg"
+}

test/errors_test.go

@@ -13,33 +13,12 @@ import (
 
 type ErrorsSuite struct {
 	suite.Suite
-	BackupBasePath      string
-	BackupBaseModule    string
-	BackupBaseCachePath string
 }
 
 func TestErrorsSuite(t *testing.T) {
 	suite.Run(t, new(ErrorsSuite))
 }
 
-func (suite *ErrorsSuite) SetupSuite() {
-	suite.BackupBaseModule = errors.BaseModule
-	suite.BackupBasePath = errors.BasePath
-	suite.BackupBaseCachePath = errors.BaseCachePath
-}
-
-func (suite *ErrorsSuite) TearDownSuite() {
-	errors.BaseModule = suite.BackupBaseModule
-	errors.BasePath = suite.BackupBasePath
-	errors.BaseCachePath = suite.BackupBaseCachePath
-}
-
-func (suite *ErrorsSuite) SetupTest() {
-	errors.BaseModule = "github.com/coditory/go-errors"
-	errors.BasePath = "**/go-errors"
-	errors.BaseCachePath = "**/mod/pkg"
-}
-
 func (suite *ErrorsSuite) TestNewError() {
 	err := errors.New("foo")
 	suite.Equal("foo", err.Error())