deprecate <1.12.x, use golangci-lint (spf13#876)

* deprecate go 1.10.x and 1.11.x
* use golangci-lint in Travis CI
* fix linting issues accordingly

.circleci/config.yml

@@ -8,6 +8,7 @@ references:
     run:
       name: "All Commands"
       command: |
+        export GO111MODULE=on
         mkdir -p bin
         curl -Lso bin/shellcheck https://github.com/caarlos0/shellcheck-docker/releases/download/v0.4.6/shellcheck
         chmod +x bin/shellcheck
@@ -29,13 +30,6 @@ jobs:
       - run:
           name: "Check formatting"
           command: diff -u <(echo -n) <(gofmt -d -s .)
-  go-previous:
-    docker:
-      - image: circleci/golang:1.11
-    working_directory: *workspace
-    steps:
-      - checkout
-      - *run_tests
   go-latest:
     docker:
       - image: circleci/golang:latest
@@ -49,5 +43,4 @@ workflows:
   main:
     jobs:
       - go-current
-      - go-previous
       - go-latest

.gitattributes

@@ -0,0 +1 @@
+* text=auto

.gitignore

@@ -37,3 +37,6 @@ cobra.test
 
 .idea/
 *.iml
+
+# test-generated files
+cobra/cmd/testproject

.golangci.yml

@@ -0,0 +1,25 @@
+run:
+  deadline: 5m
+
+linters:
+  enable:
+    - deadcode
+    - errcheck
+    - gas
+    - goconst
+    - goimports
+    - golint
+    - govet
+    - ineffassign
+    - interfacer
+    - maligned
+    - megacheck
+    - structcheck
+    - unconvert
+    - varcheck
+  enable-all: false
+  disable-all: true
+#  presets:
+#    - bugs
+#    - unused
+  fast: false

.travis.yml

@@ -1,31 +1,27 @@
 language: go
 
 stages:
-  - diff
+  - lint
   - test
 
 go:
-  - 1.11.x
   - 1.12.x
   - 1.13.x
   - tip
 
-env:
-  - GO111MODULE=on
-
-matrix:
-  allow_failures:
-    - go: tip
-  include:
-    - stage: diff
-      go: 1.13.x
-      script: diff -u <(echo -n) <(gofmt -d -s .)
+env: GO111MODULE=on
 
 before_install: go get -u github.com/kyoh86/richgo
 
 script:
   - richgo test -v ./...
   - go build
-  - if [ -z $NOVET ]; then
-      diff -u <(echo -n) <(go vet . 2>&1 | grep -vE 'ExampleCommand|bash_completions.*Fprint');
-    fi
+
+matrix:
+  allow_failures:
+    - go: tip
+  include:
+    - stage: lint
+      go: 1.13.x
+      before_install: go get github.com/golangci/golangci-lint/cmd/golangci-lint@v1.19.1
+      script: golangci-lint run -v

README.md

@@ -213,7 +213,6 @@ import (
   "fmt"
   "os"
 
-  homedir "github.com/mitchellh/go-homedir"
   "github.com/spf13/cobra"
   "github.com/spf13/viper"
 )
@@ -241,7 +240,7 @@ func initConfig() {
     viper.SetConfigFile(cfgFile)
   } else {
     // Find home directory.
-    home, err := homedir.Dir()
+    home, err := os.UserHomeDir()
     if err != nil {
       fmt.Println(err)
       os.Exit(1)

bash_completions.go

@@ -19,9 +19,9 @@ const (
 	BashCompSubdirsInDir    = "cobra_annotation_bash_completion_subdirs_in_dir"
 )
 
-func writePreamble(buf *bytes.Buffer, name string) {
-	buf.WriteString(fmt.Sprintf("# bash completion for %-36s -*- shell-script -*-\n", name))
-	buf.WriteString(fmt.Sprintf(`
+func writePreamble(buf io.StringWriter, name string) {
+	WrStringAndCheck(buf, fmt.Sprintf("# bash completion for %-36s -*- shell-script -*-\n", name))
+	WrStringAndCheck(buf, fmt.Sprintf(`
 __%[1]s_debug()
 {
     if [[ -n ${BASH_COMP_DEBUG_FILE} ]]; then
@@ -281,10 +281,10 @@ __%[1]s_handle_word()
 `, name))
 }
 
-func writePostscript(buf *bytes.Buffer, name string) {
+func writePostscript(buf io.StringWriter, name string) {
 	name = strings.Replace(name, ":", "__", -1)
-	buf.WriteString(fmt.Sprintf("__start_%s()\n", name))
-	buf.WriteString(fmt.Sprintf(`{
+	WrStringAndCheck(buf, fmt.Sprintf("__start_%s()\n", name))
+	WrStringAndCheck(buf, fmt.Sprintf(`{
     local cur prev words cword
     declare -A flaghash 2>/dev/null || :
     declare -A aliashash 2>/dev/null || :
@@ -310,101 +310,104 @@ func writePostscript(buf *bytes.Buffer, name string) {
 }
 
 `, name))
-	buf.WriteString(fmt.Sprintf(`if [[ $(type -t compopt) = "builtin" ]]; then
+	WrStringAndCheck(buf, fmt.Sprintf(`if [[ $(type -t compopt) = "builtin" ]]; then
     complete -o default -F __start_%s %s
 else
     complete -o default -o nospace -F __start_%s %s
 fi
 
 `, name, name, name, name))
-	buf.WriteString("# ex: ts=4 sw=4 et filetype=sh\n")
+	WrStringAndCheck(buf, "# ex: ts=4 sw=4 et filetype=sh\n")
 }
 
-func writeCommands(buf *bytes.Buffer, cmd *Command) {
-	buf.WriteString("    commands=()\n")
+func writeCommands(buf io.StringWriter, cmd *Command) {
+	WrStringAndCheck(buf, "    commands=()\n")
 	for _, c := range cmd.Commands() {
 		if !c.IsAvailableCommand() || c == cmd.helpCommand {
 			continue
 		}
-		buf.WriteString(fmt.Sprintf("    commands+=(%q)\n", c.Name()))
+		WrStringAndCheck(buf, fmt.Sprintf("    commands+=(%q)\n", c.Name()))
 		writeCmdAliases(buf, c)
 	}
-	buf.WriteString("\n")
+	WrStringAndCheck(buf, "\n")
 }
 
-func writeFlagHandler(buf *bytes.Buffer, name string, annotations map[string][]string, cmd *Command) {
+func writeFlagHandler(buf io.StringWriter, name string, annotations map[string][]string, cmd *Command) {
 	for key, value := range annotations {
 		switch key {
 		case BashCompFilenameExt:
-			buf.WriteString(fmt.Sprintf("    flags_with_completion+=(%q)\n", name))
+			WrStringAndCheck(buf, fmt.Sprintf("    flags_with_completion+=(%q)\n", name))
 
 			var ext string
 			if len(value) > 0 {
 				ext = fmt.Sprintf("__%s_handle_filename_extension_flag ", cmd.Root().Name()) + strings.Join(value, "|")
 			} else {
 				ext = "_filedir"
 			}
-			buf.WriteString(fmt.Sprintf("    flags_completion+=(%q)\n", ext))
+			WrStringAndCheck(buf, fmt.Sprintf("    flags_completion+=(%q)\n", ext))
 		case BashCompCustom:
-			buf.WriteString(fmt.Sprintf("    flags_with_completion+=(%q)\n", name))
+			WrStringAndCheck(buf, fmt.Sprintf("    flags_with_completion+=(%q)\n", name))
+
 			if len(value) > 0 {
 				handlers := strings.Join(value, "; ")
-				buf.WriteString(fmt.Sprintf("    flags_completion+=(%q)\n", handlers))
+				WrStringAndCheck(buf, fmt.Sprintf("    flags_completion+=(%q)\n", handlers))
 			} else {
-				buf.WriteString("    flags_completion+=(:)\n")
+				WrStringAndCheck(buf, "    flags_completion+=(:)\n")
 			}
 		case BashCompSubdirsInDir:
-			buf.WriteString(fmt.Sprintf("    flags_with_completion+=(%q)\n", name))
+			WrStringAndCheck(buf, fmt.Sprintf("    flags_with_completion+=(%q)\n", name))
 
 			var ext string
 			if len(value) == 1 {
 				ext = fmt.Sprintf("__%s_handle_subdirs_in_dir_flag ", cmd.Root().Name()) + value[0]
 			} else {
 				ext = "_filedir -d"
 			}
-			buf.WriteString(fmt.Sprintf("    flags_completion+=(%q)\n", ext))
+			WrStringAndCheck(buf, fmt.Sprintf("    flags_completion+=(%q)\n", ext))
 		}
 	}
 }
 
-func writeShortFlag(buf *bytes.Buffer, flag *pflag.Flag, cmd *Command) {
+const cbn = "\")\n"
+
+func writeShortFlag(buf io.StringWriter, flag *pflag.Flag, cmd *Command) {
 	name := flag.Shorthand
 	format := "    "
 	if len(flag.NoOptDefVal) == 0 {
 		format += "two_word_"
 	}
-	format += "flags+=(\"-%s\")\n"
-	buf.WriteString(fmt.Sprintf(format, name))
+	format += "flags+=(\"-%s" + cbn
+	WrStringAndCheck(buf, fmt.Sprintf(format, name))
 	writeFlagHandler(buf, "-"+name, flag.Annotations, cmd)
 }
 
-func writeFlag(buf *bytes.Buffer, flag *pflag.Flag, cmd *Command) {
+func writeFlag(buf io.StringWriter, flag *pflag.Flag, cmd *Command) {
 	name := flag.Name
 	format := "    flags+=(\"--%s"
 	if len(flag.NoOptDefVal) == 0 {
 		format += "="
 	}
-	format += "\")\n"
-	buf.WriteString(fmt.Sprintf(format, name))
+	format += cbn
+	WrStringAndCheck(buf, fmt.Sprintf(format, name))
 	if len(flag.NoOptDefVal) == 0 {
-		format = "    two_word_flags+=(\"--%s\")\n"
-		buf.WriteString(fmt.Sprintf(format, name))
+		format = "    two_word_flags+=(\"--%s" + cbn
+		WrStringAndCheck(buf, fmt.Sprintf(format, name))
 	}
 	writeFlagHandler(buf, "--"+name, flag.Annotations, cmd)
 }
 
-func writeLocalNonPersistentFlag(buf *bytes.Buffer, flag *pflag.Flag) {
+func writeLocalNonPersistentFlag(buf io.StringWriter, flag *pflag.Flag) {
 	name := flag.Name
 	format := "    local_nonpersistent_flags+=(\"--%s"
 	if len(flag.NoOptDefVal) == 0 {
 		format += "="
 	}
-	format += "\")\n"
-	buf.WriteString(fmt.Sprintf(format, name))
+	format += cbn
+	WrStringAndCheck(buf, fmt.Sprintf(format, name))
 }
 
-func writeFlags(buf *bytes.Buffer, cmd *Command) {
-	buf.WriteString(`    flags=()
+func writeFlags(buf io.StringWriter, cmd *Command) {
+	WrStringAndCheck(buf, `    flags=()
     two_word_flags=()
     local_nonpersistent_flags=()
     flags_with_completion=()
@@ -434,11 +437,11 @@ func writeFlags(buf *bytes.Buffer, cmd *Command) {
 		}
 	})
 
-	buf.WriteString("\n")
+	WrStringAndCheck(buf, "\n")
 }
 
-func writeRequiredFlag(buf *bytes.Buffer, cmd *Command) {
-	buf.WriteString("    must_have_one_flag=()\n")
+func writeRequiredFlag(buf io.StringWriter, cmd *Command) {
+	WrStringAndCheck(buf, "    must_have_one_flag=()\n")
 	flags := cmd.NonInheritedFlags()
 	flags.VisitAll(func(flag *pflag.Flag) {
 		if nonCompletableFlag(flag) {
@@ -451,49 +454,49 @@ func writeRequiredFlag(buf *bytes.Buffer, cmd *Command) {
 				if flag.Value.Type() != "bool" {
 					format += "="
 				}
-				format += "\")\n"
-				buf.WriteString(fmt.Sprintf(format, flag.Name))
+				format += cbn
+				WrStringAndCheck(buf, fmt.Sprintf(format, flag.Name))
 
 				if len(flag.Shorthand) > 0 {
-					buf.WriteString(fmt.Sprintf("    must_have_one_flag+=(\"-%s\")\n", flag.Shorthand))
+					WrStringAndCheck(buf, fmt.Sprintf("    must_have_one_flag+=(\"-%s"+cbn, flag.Shorthand))
 				}
 			}
 		}
 	})
 }
 
-func writeRequiredNouns(buf *bytes.Buffer, cmd *Command) {
-	buf.WriteString("    must_have_one_noun=()\n")
-	sort.Sort(sort.StringSlice(cmd.ValidArgs))
+func writeRequiredNouns(buf io.StringWriter, cmd *Command) {
+	WrStringAndCheck(buf, "    must_have_one_noun=()\n")
+	sort.Strings(cmd.ValidArgs)
 	for _, value := range cmd.ValidArgs {
-		buf.WriteString(fmt.Sprintf("    must_have_one_noun+=(%q)\n", value))
+		WrStringAndCheck(buf, fmt.Sprintf("    must_have_one_noun+=(%q)\n", value))
 	}
 }
 
-func writeCmdAliases(buf *bytes.Buffer, cmd *Command) {
+func writeCmdAliases(buf io.StringWriter, cmd *Command) {
 	if len(cmd.Aliases) == 0 {
 		return
 	}
 
-	sort.Sort(sort.StringSlice(cmd.Aliases))
+	sort.Strings(cmd.Aliases)
 
-	buf.WriteString(fmt.Sprint(`    if [[ -z "${BASH_VERSION}" || "${BASH_VERSINFO[0]}" -gt 3 ]]; then`, "\n"))
+	WrStringAndCheck(buf, fmt.Sprint(`    if [[ -z "${BASH_VERSION}" || "${BASH_VERSINFO[0]}" -gt 3 ]]; then`, "\n"))
 	for _, value := range cmd.Aliases {
-		buf.WriteString(fmt.Sprintf("        command_aliases+=(%q)\n", value))
-		buf.WriteString(fmt.Sprintf("        aliashash[%q]=%q\n", value, cmd.Name()))
+		WrStringAndCheck(buf, fmt.Sprintf("        command_aliases+=(%q)\n", value))
+		WrStringAndCheck(buf, fmt.Sprintf("        aliashash[%q]=%q\n", value, cmd.Name()))
 	}
-	buf.WriteString(`    fi`)
-	buf.WriteString("\n")
+	WrStringAndCheck(buf, `    fi`)
+	WrStringAndCheck(buf, "\n")
 }
-func writeArgAliases(buf *bytes.Buffer, cmd *Command) {
-	buf.WriteString("    noun_aliases=()\n")
-	sort.Sort(sort.StringSlice(cmd.ArgAliases))
+func writeArgAliases(buf io.StringWriter, cmd *Command) {
+	WrStringAndCheck(buf, "    noun_aliases=()\n")
+	sort.Strings(cmd.ArgAliases)
 	for _, value := range cmd.ArgAliases {
-		buf.WriteString(fmt.Sprintf("    noun_aliases+=(%q)\n", value))
+		WrStringAndCheck(buf, fmt.Sprintf("    noun_aliases+=(%q)\n", value))
 	}
 }
 
-func gen(buf *bytes.Buffer, cmd *Command) {
+func gen(buf io.StringWriter, cmd *Command) {
 	for _, c := range cmd.Commands() {
 		if !c.IsAvailableCommand() || c == cmd.helpCommand {
 			continue
@@ -505,22 +508,22 @@ func gen(buf *bytes.Buffer, cmd *Command) {
 	commandName = strings.Replace(commandName, ":", "__", -1)
 
 	if cmd.Root() == cmd {
-		buf.WriteString(fmt.Sprintf("_%s_root_command()\n{\n", commandName))
+		WrStringAndCheck(buf, fmt.Sprintf("_%s_root_command()\n{\n", commandName))
 	} else {
-		buf.WriteString(fmt.Sprintf("_%s()\n{\n", commandName))
+		WrStringAndCheck(buf, fmt.Sprintf("_%s()\n{\n", commandName))
 	}
 
-	buf.WriteString(fmt.Sprintf("    last_command=%q\n", commandName))
-	buf.WriteString("\n")
-	buf.WriteString("    command_aliases=()\n")
-	buf.WriteString("\n")
+	WrStringAndCheck(buf, fmt.Sprintf("    last_command=%q\n", commandName))
+	WrStringAndCheck(buf, "\n")
+	WrStringAndCheck(buf, "    command_aliases=()\n")
+	WrStringAndCheck(buf, "\n")
 
 	writeCommands(buf, cmd)
 	writeFlags(buf, cmd)
 	writeRequiredFlag(buf, cmd)
 	writeRequiredNouns(buf, cmd)
 	writeArgAliases(buf, cmd)
-	buf.WriteString("}\n\n")
+	WrStringAndCheck(buf, "}\n\n")
 }
 
 // GenBashCompletion generates bash completion file and writes to the passed writer.