Merge pull request #34 from gemcook/feature/add-readme

feat: add readme

README.md

@@ -0,0 +1,112 @@
+# merr
+
+[![Analysis](https://github.com/gemcook/merr/actions/workflows/analysis.yml/badge.svg)](https://github.com/gemcook/merr/actions/workflows/analysis.yml) ![GitHub go.mod Go version](https://img.shields.io/github/go-mod/go-version/gemcook/merr)
+
+`merr` is a package that binds multiple errors.
+
+## Features
+
+`merr` has pretty print, which outputs the bound errors in a well-formatted and easy-to-understand format.
+It is also possible to change the output destination if necessary, which is very useful for debugging.
+
+## Installation
+
+```sh
+go get -u github.com/gemcook/merr
+```
+
+## Usage
+
+```go
+import "github.com/gemcook/merr"
+```
+
+### Appends error
+
+Appends error to list of errors.
+If there is no error list, it creates a new one.
+
+```go
+multiError := merr.New()
+
+for i := 0; i < 10; i++ {
+    if err := something(); err != nil {
+        multiError.Append(err)
+    }
+}
+```
+
+### Print list of error
+
+Prints the object of the list of errors, separated by `,\n`.
+
+```go
+multiError := merr.New()
+
+for i := 0; i < 10; i++ {
+    // something() returns &errors.errorString{s: "something error"}
+    if err := something(); err != nil {
+        multiError.Append(err)
+    }
+}
+
+fmt.Println(multiError.Error())
+```
+
+```
+"something error",
+"something error",
+  .
+  .
+  .
+"something error"
+```
+
+### Pretty print
+
+Prints a list of errors in a well-formatted, easy-to-understand format.
+
+```go
+multiError := merr.New()
+
+for i := 0; i < 10; i++ {
+    // something() returns &errors.errorString{s: "something error"}
+    if err := something(); err != nil {
+        multiError.Append(err)
+    }
+}
+
+multiError.PrettyPrint()
+```
+
+```
+Errors[
+  &errors.errorString{
+    s: "something error",
+  },
+  &errors.errorString{
+    s: "something error",
+  },
+  &errors.errorString{
+    s: "something error",
+  },
+  .
+  .
+  .
+  &errors.errorString{
+    s: "something error",
+  },
+]
+```
+
+The default output destination is the **standard output**.
+You can also change the output destination.
+
+```go
+buf := bytes.NewBuffer(nil)
+merr.SetOutput(buf)
+```
+
+## License
+
+MIT License

errs.go

@@ -1,4 +1,4 @@
-package errs
+package merr
 
 import (
 	"bytes"
@@ -27,7 +27,7 @@ var (
 
 var formatter = func(e *errs) string {
 	var result string
-	suffix := ",\n"
+	suffix := "\n"
 	for i, err := range e.Errors {
 		if len(e.Errors)-1 == i {
 			suffix = ""

errs_test.go

@@ -1,4 +1,4 @@
-package errs
+package merr
 
 import (
 	"bytes"
@@ -35,7 +35,7 @@ func Test_errs_Error(t *testing.T) {
 					fmt.Errorf("%s", "error2"),
 				},
 			},
-			"error1,\nerror2",
+			"error1\nerror2",
 		},
 		{
 			"check/error/wrapped",
@@ -46,7 +46,7 @@ func Test_errs_Error(t *testing.T) {
 					fmt.Errorf("%w", &somethingError{}),
 				},
 			},
-			"something error,\nsomething error",
+			"something error\nsomething error",
 		},
 	}
 	for _, tt := range tests {
@@ -191,7 +191,7 @@ func Test_errs_PrettyPrint(t *testing.T) {
 					&somethingError{},
 				},
 			},
-			"Errors[\n  &errs.somethingError{},\n]",
+			"Errors[\n  &merr.somethingError{},\n]",
 		},
 		{
 			"print nil",

example_test.go

@@ -1,10 +1,10 @@
-package errs_test
+package merr_test
 
 import (
 	"fmt"
 	"os"
 
-	"github.com/gemcook/errs"
+	"github.com/gemcook/merr"
 )
 
 type structError struct {
@@ -28,7 +28,7 @@ func (*ptrError) Error() string {
 }
 
 func Example() {
-	err := errs.New()
+	err := merr.New()
 
 	// error interface
 	err.Append(fmt.Errorf("%w", fmt.Errorf("wrap error")))
@@ -49,7 +49,7 @@ func Example() {
 	}
 	err.Append(ptrErr)
 
-	errs.SetOutput(os.Stdout)
+	merr.SetOutput(os.Stdout)
 	err.PrettyPrint()
 
 	// output:
@@ -60,12 +60,12 @@ func Example() {
 	//       s: "wrap error",
 	//     },
 	//   },
-	//   errs_test.structError{
+	//   merr_test.structError{
 	//     i:   1,
 	//     str: "error",
 	//     b:   true,
 	//   },
-	//   &errs_test.ptrError{
+	//   &merr_test.ptrError{
 	//     i:   1,
 	//     str: "error",
 	//     b:   true,

go.mod

@@ -1,4 +1,4 @@
-module github.com/gemcook/errs
+module github.com/gemcook/merr
 
 go 1.17