refactor

.golangci.yml

@@ -0,0 +1,12 @@
+linters:
+  enable:
+    - gci
+    - revive
+    - exportloopref
+    - errorlint
+    - dupl
+    - dupl
+    - misspell
+    - tagliatelle
+    - unparam
+    - wastedassign

cmd_auth.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 	"net/http"
@@ -133,7 +134,7 @@ func slackFetchAccessToken(clientID, clientSecret, authCode, redirectURI string)
 	dec := json.NewDecoder(resp.Body)
 	t := slackOAuth2AuthedTokens{}
 	err = dec.Decode(&t)
-	if err == io.EOF {
+	if errors.Is(err, io.EOF) {
 		return "", fmt.Errorf("auth response from the server is empty")
 	} else if err != nil {
 		return "", err

cmd_delete.go

@@ -48,7 +48,7 @@ func (c *deleteCmd) Before(global globalCmd) error {
 		}
 
 		for _, ch := range chans {
-			if strings.ToLower(c.Chan) == strings.ToLower(ch.Name) {
+			if strings.EqualFold(c.Chan, ch.Name) {
 				c.innerChan = ch.ID
 			}
 		}

cmd_download.go

@@ -54,7 +54,7 @@ func (c *downloadCmd) Before(global globalCmd) error {
 		}
 
 		for _, ch := range chans {
-			if strings.ToLower(c.Chan) == strings.ToLower(ch.Name) {
+			if strings.EqualFold(c.Chan, ch.Name) {
 				c.innerChan = ch.ID
 			}
 		}

cmd_list.go

@@ -49,7 +49,7 @@ func (c *listCmd) Before(global globalCmd) error {
 		}
 
 		for _, ch := range chans {
-			if strings.ToLower(c.Chan) == strings.ToLower(ch.Name) {
+			if strings.EqualFold(c.Chan, ch.Name) {
 				c.innerChan = ch.ID
 			}
 		}

config.go

@@ -3,7 +3,6 @@ package main
 import (
 	"bytes"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 
@@ -65,5 +64,5 @@ func saveConfig(config *config, filePath string) error {
 	if err := toml.NewEncoder(buf).Encode(config); err != nil {
 		return err
 	}
-	return ioutil.WriteFile(filePath, buf.Bytes(), 0700)
+	return os.WriteFile(filePath, buf.Bytes(), 0700)
 }

file.go

@@ -56,10 +56,7 @@ func testProp(f slack.File, prop string) bool {
 }
 
 func fileProp(f slack.File, prop string) string {
-	p := strings.ToLower(prop)
-	if strings.HasPrefix(p, "-") {
-		p = p[1:]
-	}
+	p := strings.TrimPrefix(strings.ToLower(prop), "-")
 
 	switch p {
 	case "id":
@@ -135,7 +132,6 @@ func fileProp(f slack.File, prop string) string {
 	default:
 		return ""
 	}
-	return ""
 }
 
 func bool2NumStr(b bool) string {

minredir/minredir.go

@@ -11,7 +11,7 @@ import (
 	"crypto/x509/pkix"
 	"encoding/pem"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"log"
 	"math/big"
 	"net"
@@ -114,7 +114,7 @@ func LaunchMinServerTLS(port int, extractor func(r *http.Request, resultChan cha
 	defer ln.Close()
 
 	// OMAJINAI: call srv.setupHTTP2_ServeTLS()
-	log.SetOutput(ioutil.Discard)
+	log.SetOutput(io.Discard)
 	server.ServeTLS(nil, "", "")
 	defer log.SetOutput(os.Stderr)