chore(ci): add golangci-lint action and apply linting changes (#120)

BREAKING CHANGE: `JiraIssueId` has been renamed to `JiraIssueID`. This impacts the value for `pattern_maps` in `config.yml`. * chore(ci): add golangci-lint action * chore(lint): address errcheck lint failures * chore(lint): address misspell lint failures * chore(lint): address gocritic lint failures * chore(lint): address golint lint failures * chore(lint): address structcheck lint failures * chore(lint): address gosimple lint failures * chore(lint): address gofmt lint failures * chore(ci): port to official golangci-lint github action * Update golangci configuration for better coverage Signed-off-by: Khosrow Moossavi <khos2ow@gmail.com> * fix: file is not goimports-ed Signed-off-by: Khosrow Moossavi <khos2ow@gmail.com> * fix: golint and exported functions comments Signed-off-by: Khosrow Moossavi <khos2ow@gmail.com> * chore(lint): address gosec G304 warning * chore(lint): address uparam warnings * chore(lint): address scopelint lint failures * fix: cyclomatic complexity Signed-off-by: Khosrow Moossavi <khos2ow@gmail.com> * chore(lint): address prealloc warning, noting that we are warning for now * chore(lint): address govet and errorlint failures * chore: clean up defer logic when checking errors Co-authored-by: Khosrow Moossavi <khos2ow@gmail.com>
2026-01-22 18:06:11 +00:00 · 2021-03-16 21:24:36 -05:00 · 2021-03-16 21:24:36 -05:00 · ae3382b7c8
commit ae3382b7c8
parent 2c3d3f400e
37 changed files with 391 additions and 177 deletions
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@ -0,0 +1,18 @@
+name: lint
+
+on:
+  pull_request:
+    types: ['opened', 'synchronize']
+  push:
+    branches:
+      - master
+jobs:
+  golangci:
+    name: lint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@v2
+        with:
+          version: v1.38
--- a/.golangci.yml
+++ b/.golangci.yml
@ -0,0 +1,155 @@
+# https://golangci-lint.run/usage/configuration/
+run:
+  timeout: 10m
+  deadline: 5m
+
+  tests: true
+
+output:
+  format: tab
+
+linters-settings:
+  govet:
+    # report about shadowed variables
+    check-shadowing: true
+
+  golint:
+    # minimal confidence for issues, default is 0.8
+    min-confidence: 0.8
+
+  gofmt:
+    # simplify code: gofmt with `-s` option, true by default
+    simplify: true
+
+  goimports:
+    # put imports beginning with prefix after 3rd-party packages;
+    # it's a comma-separated list of prefixes
+    local-prefixes: github.com/git-chglog/git-chglog
+
+  gocyclo:
+    # minimal code complexity to report, 30 by default (but we recommend 10-20)
+    min-complexity: 10
+
+  maligned:
+    # print struct with more effective memory layout or not, false by default
+    suggest-new: true
+
+  dupl:
+    # tokens count to trigger issue, 150 by default
+    threshold: 100
+
+  goconst:
+    # minimal length of string constant, 3 by default
+    min-len: 3
+    # minimal occurrences count to trigger, 3 by default
+    min-occurrences: 5
+
+  lll:
+    # tab width in spaces. Default to 1.
+    tab-width: 1
+
+  unused:
+    # treat code as a program (not a library) and report unused exported identifiers; default is false.
+    # XXX: if you enable this setting, unused will report a lot of false-positives in text editors:
+    # if it's called for subdir of a project it can't find funcs usages. All text editor integrations
+    # with golangci-lint call it on a directory with the changed file.
+    check-exported: false
+
+  unparam:
+    # Inspect exported functions, default is false. Set to true if no external program/library imports your code.
+    # XXX: if you enable this setting, unparam will report a lot of false-positives in text editors:
+    # if it's called for subdir of a project it can't find external interfaces. All text editor integrations
+    # with golangci-lint call it on a directory with the changed file.
+    check-exported: false
+
+  nakedret:
+    # make an issue if func has more lines of code than this setting and it has naked returns; default is 30
+    max-func-lines: 30
+
+  prealloc:
+    # XXX: we don't recommend using this linter before doing performance profiling.
+    # For most programs usage of prealloc will be a premature optimization.
+
+    # Report preallocation suggestions only on simple loops that have no returns/breaks/continues/gotos in them.
+    # True by default.
+    simple: true
+    range-loops: true # Report preallocation suggestions on range loops, true by default
+    for-loops: false # Report preallocation suggestions on for loops, false by default
+
+  gocritic:
+    # Enable multiple checks by tags, run `GL_DEBUG=gocritic golangci-lint` run to see all tags and checks.
+    # Empty list by default. See https://github.com/go-critic/go-critic#usage -> section "Tags".
+    enabled-tags:
+      - performance
+
+    settings: # settings passed to gocritic
+      captLocal: # must be valid enabled check name
+        paramsOnly: true
+      rangeValCopy:
+        sizeThreshold: 32
+
+  misspell:
+    locale: US
+
+linters:
+  enable:
+    - megacheck
+    - govet
+    - gocyclo
+    - gocritic
+    - interfacer
+    - goconst
+    - goimports
+    - gofmt  # We enable this as well as goimports for its simplify mode.
+    - prealloc
+    - golint
+    - unconvert
+    - misspell
+    - nakedret
+    - dupl
+    - depguard
+
+  presets:
+    - bugs
+    - unused
+  fast: false
+
+issues:
+  # Excluding configuration per-path and per-linter
+  exclude-rules:
+    # Exclude some linters from running on tests files.
+    - path: _test(ing)?\.go
+      linters:
+        - gocyclo
+        - errcheck
+        - dupl
+        - gosec
+        - scopelint
+        - unparam
+
+    # These are performance optimisations rather than style issues per se.
+    # They warn when function arguments or range values copy a lot of memory
+    # rather than using a pointer.
+    - text: "(hugeParam|rangeValCopy):"
+      linters:
+      - gocritic
+
+  # Independently from option `exclude` we use default exclude patterns,
+  # it can be disabled by this option. To list all
+  # excluded by default patterns execute `golangci-lint run --help`.
+  # Default value for this option is true.
+  exclude-use-default: false
+
+  # Show only new issues: if there are unstaged changes or untracked files,
+  # only those changes are analyzed, else only changes in HEAD~ are analyzed.
+  # It's a super-useful option for integration of golangci-lint into existing
+  # large codebase. It's not practical to fix all existing issues at the moment
+  # of integration: much better don't allow issues in new code.
+  # Default is false.
+  new: false
+
+  # Maximum issues count per one linter. Set to 0 to disable. Default is 50.
+  max-per-linter: 0
+
+  # Maximum count of issues with the same text. Set to 0 to disable. Default is 3.
+  max-same-issues: 0
--- a/4
+++ b/4
@ -20,3 +20,7 @@ install:
 .PHONY: changelog
 changelog:
 	@git-chglog --next-tag $(tag) $(tag)
+
+.PHONY: lint
+lint:
+	@golangci-lint run
--- a/README.md
+++ b/README.md
@ -522,7 +522,7 @@ The following is a sample pattern:
    pattern: "^(?:(\\w*)|(?:\\[(.*)\\])?)\\:\\s(.*)$"
    pattern_maps:
      - Type
-      - JiraIssueId
+      - JiraIssueID
      - Subject
  ```

@ -646,6 +646,8 @@ We alway welcome your contributions :clap:
 1. Fork (https://github.com/git-chglog/git-chglog) :tada:
 1. Create a feature branch :coffee:
 1. Run test suite with the `$ make test` command and confirm that it passes :zap:
+1. Run linters with the `$ make lint` command and confirm it passes :broom:
+   - The project uses [golangci-lint](https://golangci-lint.run/usage/install/#local-installation)
 1. Commit your changes :memo:
 1. Rebase your local changes against the `master` branch :bulb:
 1. Create new Pull Request :love_letter:
--- a/chglog.go
+++ b/chglog.go
@ -5,13 +5,14 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"log"
 	"os"
 	"path/filepath"
 	"strings"
 	"text/template"
 	"time"

-	gitcmd "github.com/tsuyoshiwada/go-gitcmd"
+	"github.com/tsuyoshiwada/go-gitcmd"
 )

 // Options is an option used to process commits
@ -37,7 +38,7 @@ type Options struct {
 	NoteKeywords                []string            // Keyword list to find `Note`. A semicolon is a separator, like `<keyword>:` (e.g. `BREAKING CHANGE`)
 	JiraUsername                string
 	JiraToken                   string
-	JiraUrl                     string
+	JiraURL                     string
 	JiraTypeMaps                map[string]string
 	JiraIssueDescriptionPattern string
 	Paths                       []string // Path filter
@ -138,7 +139,11 @@ func (gen *Generator) Generate(w io.Writer, query string) error {
 	if err != nil {
 		return err
 	}
-	defer back()
+	defer func() {
+		if err = back(); err != nil {
+			log.Fatal(err)
+		}
+	}()

 	tags, first, err := gen.getTags(query)
 	if err != nil {
@ -269,7 +274,7 @@ func (gen *Generator) getTags(query string) ([]*Tag, string, error) {

 		// Assign the date with `readVersions()`
 		tags = append([]*Tag{
-			&Tag{
+			{
 				Name:     next,
 				Subject:  next,
 				Previous: previous,
@ -318,30 +323,18 @@ func (gen *Generator) render(w io.Writer, unreleased *Unreleased, versions []*Ve
 		"datetime": func(layout string, input time.Time) string {
 			return input.Format(layout)
 		},
-		// check whether substs is withing s
-		"contains": func(s, substr string) bool {
-			return strings.Contains(s, substr)
-		},
+		// check whether substr is within s
+		"contains": strings.Contains,
 		// check whether s begins with prefix
-		"hasPrefix": func(s, prefix string) bool {
-			return strings.HasPrefix(s, prefix)
-		},
+		"hasPrefix": strings.HasPrefix,
 		// check whether s ends with suffix
-		"hasSuffix": func(s, suffix string) bool {
-			return strings.HasSuffix(s, suffix)
-		},
+		"hasSuffix": strings.HasSuffix,
 		// replace the first n instances of old with new
-		"replace": func(s, old, new string, n int) string {
-			return strings.Replace(s, old, new, n)
-		},
+		"replace": strings.Replace,
 		// lower case a string
-		"lower": func(s string) string {
-			return strings.ToLower(s)
-		},
+		"lower": strings.ToLower,
 		// upper case a string
-		"upper": func(s string) string {
-			return strings.ToUpper(s)
-		},
+		"upper": strings.ToUpper,
 		// upper case the first character of a string
 		"upperFirst": func(s string) string {
 			if len(s) > 0 {
--- a/chglog_test.go
+++ b/chglog_test.go
@ -32,17 +32,17 @@ func TestMain(m *testing.M) {
 func setup(dir string, setupRepo func(commitFunc, tagFunc, gitcmd.Client)) {
 	testDir := filepath.Join(cwd, testRepoRoot, dir)

-	os.RemoveAll(testDir)
-	os.MkdirAll(testDir, os.ModePerm)
-	os.Chdir(testDir)
+	_ = os.RemoveAll(testDir)
+	_ = os.MkdirAll(testDir, os.ModePerm)
+	_ = os.Chdir(testDir)

 	loc, _ := time.LoadLocation("UTC")
 	time.Local = loc

 	git := gitcmd.New(nil)
-	git.Exec("init")
-	git.Exec("config", "user.name", "test_user")
-	git.Exec("config", "user.email", "test@example.com")
+	_, _ = git.Exec("init")
+	_, _ = git.Exec("config", "user.name", "test_user")
+	_, _ = git.Exec("config", "user.email", "test@example.com")

 	var commit = func(date, subject, body string) {
 		msg := subject
@ -51,21 +51,21 @@ func setup(dir string, setupRepo func(commitFunc, tagFunc, gitcmd.Client)) {
 		}
 		t, _ := time.Parse(internalTimeFormat, date)
 		d := t.Format("Mon Jan 2 15:04:05 2006 +0000")
-		git.Exec("commit", "--allow-empty", "--date", d, "-m", msg)
+		_, _ = git.Exec("commit", "--allow-empty", "--date", d, "-m", msg)
 	}

 	var tag = func(name string) {
-		git.Exec("tag", name)
+		_, _ = git.Exec("tag", name)
 	}

 	setupRepo(commit, tag, git)

-	os.Chdir(cwd)
+	_ = os.Chdir(cwd)
 }

 func cleanup() {
-	os.Chdir(cwd)
-	os.RemoveAll(filepath.Join(cwd, testRepoRoot))
+	_ = os.Chdir(cwd)
+	_ = os.RemoveAll(filepath.Join(cwd, testRepoRoot))
 }

 func TestGeneratorNotFoundTags(t *testing.T) {
@ -193,7 +193,7 @@ func TestGeneratorWithTypeScopeSubject(t *testing.T) {
 		tag("1.1.0")

 		commit("2018-01-03 00:00:00", "feat(context): Online breaking change", "BREAKING CHANGE: Online breaking change message.")
-		commit("2018-01-03 00:01:00", "feat(router): Muliple breaking change", `This is body,
+		commit("2018-01-03 00:01:00", "feat(router): Multiple breaking change", `This is body,

 BREAKING CHANGE:
 Multiple
@ -216,7 +216,7 @@ change message.`)
 			},
 			Options: &Options{
 				CommitFilters: map[string][]string{
-					"Type": []string{
+					"Type": {
 						"feat",
 						"fix",
 					},
@ -256,7 +256,7 @@ change message.`)

 	buf := &bytes.Buffer{}
 	err := gen.Generate(buf, "")
-	output := strings.Replace(strings.TrimSpace(buf.String()), "\r\n", "\n", -1)
+	output := strings.ReplaceAll(strings.TrimSpace(buf.String()), "\r\n", "\n")

 	assert.Nil(err)
 	assert.Equal(`<a name="unreleased"></a>
@ -270,7 +270,7 @@ change message.`)
 ## [2.0.0-beta.0] - 2018-01-03
 ### Features
 - **context:** Online breaking change
- **router:** Muliple breaking change
+- **router:** Multiple breaking change

 ### BREAKING CHANGE

@ -331,7 +331,7 @@ func TestGeneratorWithNextTag(t *testing.T) {
 			Options: &Options{
 				NextTag: "3.0.0",
 				CommitFilters: map[string][]string{
-					"Type": []string{
+					"Type": {
 						"feat",
 					},
 				},
@ -352,7 +352,7 @@ func TestGeneratorWithNextTag(t *testing.T) {

 	buf := &bytes.Buffer{}
 	err := gen.Generate(buf, "")
-	output := strings.Replace(strings.TrimSpace(buf.String()), "\r\n", "\n", -1)
+	output := strings.ReplaceAll(strings.TrimSpace(buf.String()), "\r\n", "\n")

 	assert.Nil(err)
 	assert.Equal(`<a name="unreleased"></a>
@ -383,7 +383,7 @@ func TestGeneratorWithNextTag(t *testing.T) {

 	buf = &bytes.Buffer{}
 	err = gen.Generate(buf, "3.0.0")
-	output = strings.Replace(strings.TrimSpace(buf.String()), "\r\n", "\n", -1)
+	output = strings.ReplaceAll(strings.TrimSpace(buf.String()), "\r\n", "\n")

 	assert.Nil(err)
 	assert.Equal(`<a name="unreleased"></a>
@ -424,7 +424,7 @@ func TestGeneratorWithTagFiler(t *testing.T) {
 			Options: &Options{
 				TagFilterPattern: "^v",
 				CommitFilters: map[string][]string{
-					"Type": []string{
+					"Type": {
 						"feat",
 					},
 				},
--- a/cmd/git-chglog/cli.go
+++ b/cmd/git-chglog/cli.go
@ -7,6 +7,7 @@ import (
 	"time"

 	"github.com/fatih/color"
+
 	chglog "github.com/git-chglog/git-chglog"
 )

--- a/cmd/git-chglog/cli_test.go
+++ b/cmd/git-chglog/cli_test.go
@ -8,8 +8,9 @@ import (
 	"regexp"
 	"testing"

-	chglog "github.com/git-chglog/git-chglog"
 	"github.com/stretchr/testify/assert"
+
+	chglog "github.com/git-chglog/git-chglog"
 )

 func TestCLIForStdout(t *testing.T) {
@ -36,7 +37,7 @@ func TestCLIForStdout(t *testing.T) {
 			if config.Bin != "/custom/bin/git" {
 				return errors.New("")
 			}
-			w.Write([]byte("success!!"))
+			_, _ = w.Write([]byte("success!!"))
 			return nil
 		},
 	}
@ -104,7 +105,7 @@ func TestCLIForFile(t *testing.T) {
 			if filepath.ToSlash(config.Bin) != "/custom/bin/git" {
 				return errors.New("")
 			}
-			w.Write([]byte("success!!"))
+			_, _ = w.Write([]byte("success!!"))
 			return nil
 		},
 	}
--- a/cmd/git-chglog/config.go
+++ b/cmd/git-chglog/config.go
@ -4,8 +4,9 @@ import (
 	"path/filepath"
 	"strings"

-	chglog "github.com/git-chglog/git-chglog"
 	"github.com/imdario/mergo"
+
+	chglog "github.com/git-chglog/git-chglog"
 )

 // Info ...
@ -49,6 +50,7 @@ type NoteOptions struct {
 	Keywords []string `yaml:"keywords"`
 }

+// JiraClientInfoOptions ...
 type JiraClientInfoOptions struct {
 	Username string `yaml:"username"`
 	Token    string `yaml:"token"`
@ -286,7 +288,7 @@ func (config *Config) Convert(ctx *CLIContext) *chglog.Config {
 		Template:   orValue(ctx.Template, config.Template),
 		Info: &chglog.Info{
 			Title:         info.Title,
-			RepositoryURL: orValue(ctx.RepositoryUrl, info.RepositoryURL),
+			RepositoryURL: orValue(ctx.RepositoryURL, info.RepositoryURL),
 		},
 		Options: &chglog.Options{
 			NextTag:                     ctx.NextTag,
@ -309,7 +311,7 @@ func (config *Config) Convert(ctx *CLIContext) *chglog.Config {
 			NoteKeywords:                opts.Notes.Keywords,
 			JiraUsername:                orValue(ctx.JiraUsername, opts.Jira.ClintInfo.Username),
 			JiraToken:                   orValue(ctx.JiraToken, opts.Jira.ClintInfo.Token),
-			JiraUrl:                     orValue(ctx.JiraUrl, opts.Jira.ClintInfo.URL),
+			JiraURL:                     orValue(ctx.JiraURL, opts.Jira.ClintInfo.URL),
 			JiraTypeMaps:                opts.Jira.Issue.TypeMaps,
 			JiraIssueDescriptionPattern: opts.Jira.Issue.DescriptionPattern,
 		},
--- a/cmd/git-chglog/config_loader.go
+++ b/cmd/git-chglog/config_loader.go
@ -2,8 +2,9 @@ package main

 import (
 	"io/ioutil"
+	"path/filepath"

-	yaml "gopkg.in/yaml.v2"
+	"gopkg.in/yaml.v2"
 )

 // ConfigLoader ...
@ -20,7 +21,8 @@ func NewConfigLoader() ConfigLoader {
 }

 func (loader *configLoaderImpl) Load(path string) (*Config, error) {
-	bytes, err := ioutil.ReadFile(path)
+	fp := filepath.Clean(path)
+	bytes, err := ioutil.ReadFile(fp)
 	if err != nil {
 		return nil, err
 	}
--- a/cmd/git-chglog/context.go
+++ b/cmd/git-chglog/context.go
@ -11,7 +11,7 @@ type CLIContext struct {
 	Stderr           io.Writer
 	ConfigPath       string
 	Template         string
-	RepositoryUrl    string
+	RepositoryURL    string
 	OutputPath       string
 	Silent           bool
 	NoColor          bool
@ -22,7 +22,7 @@ type CLIContext struct {
 	TagFilterPattern string
 	JiraUsername     string
 	JiraToken        string
-	JiraUrl          string
+	JiraURL          string
 	Paths            []string
 }

--- a/cmd/git-chglog/custom_template_builder.go
+++ b/cmd/git-chglog/custom_template_builder.go
@ -18,7 +18,7 @@ func (t *customTemplateBuilderImpl) Build(ans *Answer) (string, error) {
 	tpl += t.versionHeader(ans.Style, ans.Template)

 	// commits
-	tpl += t.commits(ans.Template, ans.CommitMessageFormat)
+	tpl += t.commits(ans.CommitMessageFormat)

 	// revert
 	if ans.IncludeReverts {
@ -75,7 +75,7 @@ func (*customTemplateBuilderImpl) versionHeader(style, template string) string {
 	return tpl
 }

-func (*customTemplateBuilderImpl) commits(template, format string) string {
+func (*customTemplateBuilderImpl) commits(format string) string {
 	var (
 		header string
 		body   string
--- a/cmd/git-chglog/initializer.go
+++ b/cmd/git-chglog/initializer.go
@ -2,17 +2,16 @@ package main

 import (
 	"fmt"
-	"github.com/git-chglog/git-chglog"
 	"path/filepath"

 	"github.com/fatih/color"
-	gitcmd "github.com/tsuyoshiwada/go-gitcmd"
+
+	chglog "github.com/git-chglog/git-chglog"
 )

 // Initializer ...
 type Initializer struct {
 	ctx                    *InitContext
-	client                 gitcmd.Client
 	fs                     FileSystem
 	logger                 *chglog.Logger
 	questioner             Questioner
--- a/cmd/git-chglog/main.go
+++ b/cmd/git-chglog/main.go
@ -3,14 +3,17 @@ package main
 import (
 	"fmt"
 	"io"
+	"log"
 	"os"

 	"github.com/fatih/color"
 	"github.com/mattn/go-colorable"
-	gitcmd "github.com/tsuyoshiwada/go-gitcmd"
+	"github.com/tsuyoshiwada/go-gitcmd"
 	"github.com/urfave/cli/v2"
 )

+// CreateApp creates and initializes CLI application
+// with description, flags, version, etc.
 func CreateApp(actionFunc cli.ActionFunc) *cli.App {
 	ttl := color.New(color.FgYellow).SprintFunc()

@ -182,6 +185,8 @@ func CreateApp(actionFunc cli.ActionFunc) *cli.App {
 	return app
 }

+// AppAction is a callback function to create initializer
+// and CLIContext and ultimately run the application.
 func AppAction(c *cli.Context) error {
 	wd, err := os.Getwd()
 	if err != nil {
@ -219,7 +224,7 @@ func AppAction(c *cli.Context) error {
 			Stderr:           colorable.NewColorableStderr(),
 			ConfigPath:       c.String("config"),
 			Template:         c.String("template"),
-			RepositoryUrl:    c.String("repository-url"),
+			RepositoryURL:    c.String("repository-url"),
 			OutputPath:       c.String("output"),
 			Silent:           c.Bool("silent"),
 			NoColor:          c.Bool("no-color"),
@ -230,7 +235,7 @@ func AppAction(c *cli.Context) error {
 			TagFilterPattern: c.String("tag-filter-pattern"),
 			JiraUsername:     c.String("jira-username"),
 			JiraToken:        c.String("jira-token"),
-			JiraUrl:          c.String("jira-url"),
+			JiraURL:          c.String("jira-url"),
 			Paths:            c.StringSlice("path"),
 		},
 		fs,
@ -245,5 +250,8 @@ func AppAction(c *cli.Context) error {

 func main() {
 	app := CreateApp(AppAction)
-	app.Run(os.Args)
+	err := app.Run(os.Args)
+	if err != nil {
+		log.Fatal(err)
+	}
 }
--- a/cmd/git-chglog/main_test.go
+++ b/cmd/git-chglog/main_test.go
@ -1,14 +1,16 @@
 package main

 import (
+	"log"
+	"testing"
+
 	"github.com/stretchr/testify/assert"
 	"github.com/urfave/cli/v2"
-	"testing"
 )

 var gAssert *assert.Assertions

-func mock_app_action(c *cli.Context) error {
+func mockAppAction(c *cli.Context) error {
 	assert := gAssert
 	assert.Equal("c.yml", c.String("config"))
 	assert.Equal("^v", c.String("tag-filter-pattern"))
@ -25,7 +27,7 @@ func TestCreateApp(t *testing.T) {
 	assert.True(true)
 	gAssert = assert

-	app := CreateApp(mock_app_action)
+	app := CreateApp(mockAppAction)
 	args := []string{
 		"git-chglog",
 		"--silent",
@ -36,5 +38,8 @@ func TestCreateApp(t *testing.T) {
 		"--next-tag", "v5",
 		"--tag-filter-pattern", "^v",
 	}
-	app.Run(args)
+	err := app.Run(args)
+	if err != nil {
+		log.Fatal(err)
+	}
 }
--- a/cmd/git-chglog/processor_factory_test.go
+++ b/cmd/git-chglog/processor_factory_test.go
@ -3,8 +3,9 @@ package main
 import (
 	"testing"

-	chglog "github.com/git-chglog/git-chglog"
 	"github.com/stretchr/testify/assert"
+
+	chglog "github.com/git-chglog/git-chglog"
 )

 func TestProcessorFactory(t *testing.T) {
--- a/cmd/git-chglog/questioner.go
+++ b/cmd/git-chglog/questioner.go
@ -6,8 +6,8 @@ import (
 	"path/filepath"
 	"strings"

-	gitcmd "github.com/tsuyoshiwada/go-gitcmd"
-	survey "github.com/AlecAivazis/survey/v2"
+	"github.com/AlecAivazis/survey/v2"
+	"github.com/tsuyoshiwada/go-gitcmd"
 )

 // Answer ...
@ -52,11 +52,12 @@ func (q *questionerImpl) Ask() (*Answer, error) {
 	t := q.fs.Exists(tpl)
 	msg := ""

-	if c && t {
+	switch {
+	case c && t:
 		msg = fmt.Sprintf("\"%s\" and \"%s\" already exists. Do you want to overwrite?", config, tpl)
-	} else if c {
+	case c:
 		msg = fmt.Sprintf("\"%s\" already exists. Do you want to overwrite?", config)
-	} else if t {
+	case t:
 		msg = fmt.Sprintf("\"%s\" already exists. Do you want to overwrite?", tpl)
 	}

--- a/cmd/git-chglog/utils.go
+++ b/cmd/git-chglog/utils.go
@ -7,7 +7,7 @@ import (
 	"strings"
 )

-var reSSH = regexp.MustCompile("^\\w+@([\\w\\.\\-]+):([\\w\\.\\-]+)\\/([\\w\\.\\-]+)$")
+var reSSH = regexp.MustCompile(`^\w+@([\w\.\-]+):([\w\.\-]+)\/([\w\.\-]+)$`)

 func remoteOriginURLToHTTP(rawurl string) string {
 	if rawurl == "" {
--- a/cmd/git-chglog/variables.go
+++ b/cmd/git-chglog/variables.go
@ -74,7 +74,7 @@ func (f *CommitMessageFormat) PatternMapString() string {
 	return fmt.Sprintf("\n%s", strings.Join(arr, "\n"))
 }

-// FilterTypeString ...
+// FilterTypesString ...
 func (f *CommitMessageFormat) FilterTypesString() string {
 	if len(f.typeSamples) == 0 {
 		return " []"
--- a/commit_extractor.go
+++ b/commit_extractor.go
@ -127,7 +127,11 @@ func (e *commitExtractor) commitGroupTitle(commit *Commit) (string, string) {
 	return raw, ttl
 }

-func (e *commitExtractor) sortCommitGroups(groups []*CommitGroup) {
+func (e *commitExtractor) sortCommitGroups(groups []*CommitGroup) { //nolint:gocyclo
+	// NOTE(khos2ow): this function is over our cyclomatic complexity goal.
+	// Be wary when adding branches, and look for functionality that could
+	// be reasonably moved into an injected dependency.
+
 	order := make(map[string]int)
 	if e.opts.CommitGroupSortBy == "Custom" {
 		for i, t := range e.opts.CommitGroupTitleOrder {
@ -136,6 +140,9 @@ func (e *commitExtractor) sortCommitGroups(groups []*CommitGroup) {
 	}

 	// groups
+	// TODO(khos2ow): move the inline sort function to
+	// conceret implementation of sort.Interface in order
+	// to reduce cyclomatic complaxity.
 	sort.Slice(groups, func(i, j int) bool {
 		if e.opts.CommitGroupSortBy == "Custom" {
 			return order[groups[i].RawTitle] < order[groups[j].RawTitle]
@ -165,6 +172,11 @@ func (e *commitExtractor) sortCommitGroups(groups []*CommitGroup) {

 	// commits
 	for _, group := range groups {
+		group := group // pin group to avoid potential bugs with passing group to lower functions
+
+		// TODO(khos2ow): move the inline sort function to
+		// conceret implementation of sort.Interface in order
+		// to reduce cyclomatic complaxity.
 		sort.Slice(group.Commits, func(i, j int) bool {
 			var (
 				a, b interface{}
@ -198,6 +210,7 @@ func (e *commitExtractor) sortNoteGroups(groups []*NoteGroup) {

 	// notes
 	for _, group := range groups {
+		group := group // pin group to avoid potential bugs with passing group to lower functions
 		sort.Slice(group.Notes, func(i, j int) bool {
 			return strings.ToLower(group.Notes[i].Title) < strings.ToLower(group.Notes[j].Title)
 		})
--- a/commit_extractor_test.go
+++ b/commit_extractor_test.go
@ -20,14 +20,14 @@ func TestCommitExtractor(t *testing.T) {

 	fixtures := []*Commit{
 		// [0]
-		&Commit{
+		{
 			Type:   "foo",
 			Scope:  "c",
 			Header: "1",
 			Notes:  []*Note{},
 		},
 		// [1]
-		&Commit{
+		{
 			Type:   "foo",
 			Scope:  "b",
 			Header: "2",
@ -37,7 +37,7 @@ func TestCommitExtractor(t *testing.T) {
 			},
 		},
 		// [2]
-		&Commit{
+		{
 			Type:   "bar",
 			Scope:  "d",
 			Header: "3",
@ -47,7 +47,7 @@ func TestCommitExtractor(t *testing.T) {
 			},
 		},
 		// [3]
-		&Commit{
+		{
 			Type:   "foo",
 			Scope:  "a",
 			Header: "4",
@ -56,7 +56,7 @@ func TestCommitExtractor(t *testing.T) {
 			},
 		},
 		// [4]
-		&Commit{
+		{
 			Type:   "",
 			Scope:  "",
 			Header: "Merge1",
@ -67,7 +67,7 @@ func TestCommitExtractor(t *testing.T) {
 			},
 		},
 		// [5]
-		&Commit{
+		{
 			Type:   "",
 			Scope:  "",
 			Header: "Revert1",
@ -81,14 +81,14 @@ func TestCommitExtractor(t *testing.T) {
 	commitGroups, mergeCommits, revertCommits, noteGroups := extractor.Extract(fixtures)

 	assert.Equal([]*CommitGroup{
-		&CommitGroup{
+		{
 			RawTitle: "bar",
 			Title:    "BAR",
 			Commits: []*Commit{
 				fixtures[2],
 			},
 		},
-		&CommitGroup{
+		{
 			RawTitle: "foo",
 			Title:    "Foo",
 			Commits: []*Commit{
@ -108,26 +108,26 @@ func TestCommitExtractor(t *testing.T) {
 	}, revertCommits)

 	assert.Equal([]*NoteGroup{
-		&NoteGroup{
+		{
 			Title: "note1-title",
 			Notes: []*Note{
 				fixtures[1].Notes[0],
 				fixtures[2].Notes[0],
 			},
 		},
-		&NoteGroup{
+		{
 			Title: "note2-title",
 			Notes: []*Note{
 				fixtures[1].Notes[1],
 			},
 		},
-		&NoteGroup{
+		{
 			Title: "note3-title",
 			Notes: []*Note{
 				fixtures[2].Notes[1],
 			},
 		},
-		&NoteGroup{
+		{
 			Title: "note4-title",
 			Notes: []*Note{
 				fixtures[3].Notes[0],
--- a/commit_filter.go
+++ b/commit_filter.go
@ -4,7 +4,11 @@ import (
 	"strings"
 )

-func commitFilter(commits []*Commit, filters map[string][]string, noCaseSensitive bool) []*Commit {
+func commitFilter(commits []*Commit, filters map[string][]string, noCaseSensitive bool) []*Commit { //nolint:gocyclo
+	// NOTE(khos2ow): this function is over our cyclomatic complexity goal.
+	// Be wary when adding branches, and look for functionality that could
+	// be reasonably moved into an injected dependency.
+
 	res := []*Commit{}

 	for _, commit := range commits {
--- a/commit_filter_test.go
+++ b/commit_filter_test.go
@ -18,27 +18,27 @@ func TestCommitFilter(t *testing.T) {
 	}

 	fixtures := []*Commit{
-		&Commit{
+		{
 			Type:    "foo",
 			Scope:   "hoge",
 			Subject: "1",
 		},
-		&Commit{
+		{
 			Type:    "foo",
 			Scope:   "fuga",
 			Subject: "2",
 		},
-		&Commit{
+		{
 			Type:    "bar",
 			Scope:   "hoge",
 			Subject: "3",
 		},
-		&Commit{
+		{
 			Type:    "bar",
 			Scope:   "fuga",
 			Subject: "4",
 		},
-		&Commit{
+		{
 			Type:    "Bar",
 			Scope:   "hogera",
 			Subject: "5",
--- a/commit_parser.go
+++ b/commit_parser.go
@ -80,7 +80,7 @@ func newCommitParser(logger *Logger, client gitcmd.Client, jiraClient JiraClient
 		reRef:                  regexp.MustCompile("(?i)(" + joinedRefActions + ")\\s?([\\w/\\.\\-]+)?(?:" + joinedIssuePrefix + ")(\\d+)"),
 		reIssue:                regexp.MustCompile("(?:" + joinedIssuePrefix + ")(\\d+)"),
 		reNotes:                regexp.MustCompile("^(?i)\\s*(" + joinedNoteKeywords + ")[:\\s]+(.*)"),
-		reMention:              regexp.MustCompile("@([\\w-]+)"),
+		reMention:              regexp.MustCompile(`@([\w-]+)`),
 		reJiraIssueDescription: regexp.MustCompile(opts.JiraIssueDescriptionPattern),
 	}
 }
@ -223,8 +223,8 @@ func (p *commitParser) processHeader(commit *Commit, input string) {
 	commit.Mentions = p.parseMentions(input)

 	// Jira
-	if commit.JiraIssueId != "" {
-		p.processJiraIssue(commit, commit.JiraIssueId)
+	if commit.JiraIssueID != "" {
+		p.processJiraIssue(commit, commit.JiraIssueID)
 	}
 }

@ -364,10 +364,10 @@ func (p *commitParser) uniqMentions(mentions []string) []string {
 	return arr
 }

-func (p *commitParser) processJiraIssue(commit *Commit, issueId string) {
-	issue, err := p.jiraClient.GetJiraIssue(commit.JiraIssueId)
+func (p *commitParser) processJiraIssue(commit *Commit, issueID string) {
+	issue, err := p.jiraClient.GetJiraIssue(commit.JiraIssueID)
 	if err != nil {
-		p.logger.Error(fmt.Sprintf("Failed to parse Jira story %s: %s\n", issueId, err))
+		p.logger.Error(fmt.Sprintf("Failed to parse Jira story %s: %s\n", issueID, err))
 		return
 	}
 	commit.Type = p.config.Options.JiraTypeMaps[issue.Fields.Type.Name]
--- a/commit_parser_test.go
+++ b/commit_parser_test.go
@ -33,7 +33,7 @@ func TestCommitParserParse(t *testing.T) {
 		mock, nil, &Config{
 			Options: &Options{
 				CommitFilters: map[string][]string{
-					"Type": []string{
+					"Type": {
 						"feat",
 						"fix",
 						"perf",
@ -79,7 +79,7 @@ func TestCommitParserParse(t *testing.T) {
 	commits, err := parser.Parse("HEAD")
 	assert.Nil(err)
 	assert.Equal([]*Commit{
-		&Commit{
+		{
 			Hash: &Hash{
 				Long:  "65cf1add9735dcc4810dda3312b0792236c97c4e",
 				Short: "65cf1add",
@ -97,7 +97,7 @@ func TestCommitParserParse(t *testing.T) {
 			Merge:  nil,
 			Revert: nil,
 			Refs: []*Ref{
-				&Ref{
+				{
 					Action: "",
 					Ref:    "123",
 					Source: "",
@ -111,7 +111,7 @@ func TestCommitParserParse(t *testing.T) {
 			Subject:  "Add new feature #123",
 			Body:     "",
 		},
-		&Commit{
+		{
 			Hash: &Hash{
 				Long:  "14ef0b6d386c5432af9292eab3c8314fa3001bc7",
 				Short: "14ef0b6d",
@ -132,24 +132,24 @@ func TestCommitParserParse(t *testing.T) {
 			},
 			Revert: nil,
 			Refs: []*Ref{
-				&Ref{
+				{
 					Action: "",
 					Ref:    "3",
 					Source: "",
 				},
-				&Ref{
+				{
 					Action: "Fixes",
 					Ref:    "3",
 					Source: "",
 				},
-				&Ref{
+				{
 					Action: "Closes",
 					Ref:    "1",
 					Source: "",
 				},
 			},
 			Notes: []*Note{
-				&Note{
+				{
 					Title: "BREAKING CHANGE",
 					Body:  "This is breaking point message.",
 				},
@ -167,7 +167,7 @@ Closes #1

 BREAKING CHANGE: This is breaking point message.`,
 		},
-		&Commit{
+		{
 			Hash: &Hash{
 				Long:  "809a8280ffd0dadb0f4e7ba9fc835e63c37d6af6",
 				Short: "809a8280",
@ -201,7 +201,7 @@ BREAKING CHANGE: This is breaking point message.`,
@hogefuga
@FooBarBaz`,
 		},
-		&Commit{
+		{
 			Hash: &Hash{
 				Long:  "74824d6bd1470b901ec7123d13a76a1b8938d8d0",
 				Short: "74824d6b",
@ -219,19 +219,19 @@ BREAKING CHANGE: This is breaking point message.`,
 			Merge:  nil,
 			Revert: nil,
 			Refs: []*Ref{
-				&Ref{
+				{
 					Action: "Fixes",
 					Ref:    "123",
 					Source: "",
 				},
-				&Ref{
+				{
 					Action: "Closes",
 					Ref:    "456",
 					Source: "username/repository",
 				},
 			},
 			Notes: []*Note{
-				&Note{
+				{
 					Title: "BREAKING CHANGE",
 					Body: fmt.Sprintf(`This is multiline breaking change note.
 It is treated as the body of the Note until a mention or reference appears.
@ -281,7 +281,7 @@ class MyController extends Controller {
 Fixes #123
 Closes username/repository#456`, "```", "```"),
 		},
-		&Commit{
+		{
 			Hash: &Hash{
 				Long:  "123456789735dcc4810dda3312b0792236c97c4e",
 				Short: "12345678",
@ -381,7 +381,7 @@ func TestCommitParserParseWithJira(t *testing.T) {
 		mock, mockJiraClient{}, &Config{
 			Options: &Options{
 				CommitFilters: map[string][]string{
-					"Type": []string{
+					"Type": {
 						"feat",
 						"fix",
 						"perf",
@ -391,7 +391,7 @@ func TestCommitParserParseWithJira(t *testing.T) {
 				HeaderPattern: "^(?:(\\w*)|(?:\\[(.*)\\])?)\\:\\s(.*)$",
 				HeaderPatternMaps: []string{
 					"Type",
-					"JiraIssueId",
+					"JiraIssueID",
 					"Subject",
 				},
 				JiraTypeMaps: map[string]string{
@ -403,7 +403,7 @@ func TestCommitParserParseWithJira(t *testing.T) {
 	commits, err := parser.Parse("HEAD")
 	assert.Nil(err)
 	commit := commits[0]
-	assert.Equal(commit.JiraIssueId, "JIRA-1111")
+	assert.Equal(commit.JiraIssueID, "JIRA-1111")
 	assert.Equal(commit.JiraIssue.Type, "Story")
 	assert.Equal(commit.JiraIssue.Summary, "summary of JIRA-1111")
 	assert.Equal(commit.JiraIssue.Description, "description of JIRA-1111")
--- a/example_test.go
+++ b/example_test.go
@ -19,7 +19,7 @@ func Example() {
 			},
 			Options: &Options{
 				CommitFilters: map[string][]string{
-					"Type": []string{
+					"Type": {
 						"feat",
 						"fix",
 					},
--- a/fields.go
+++ b/fields.go
@ -52,7 +52,7 @@ type NoteGroup struct {
 	Notes []*Note
 }

-// JiraIssue
+// JiraIssue is information about a jira ticket (type, summary, description, and labels)
 type JiraIssue struct {
 	Type        string
 	Summary     string
@ -69,13 +69,13 @@ type Commit struct {
 	Revert      *Revert // If it is not a revert commit, `nil` is assigned
 	Refs        []*Ref
 	Notes       []*Note
-	Mentions    []string // Name of the user included in the commit header or body
+	Mentions    []string   // Name of the user included in the commit header or body
 	JiraIssue   *JiraIssue // If no issue id found in header, `nil` is assigned
-	Header      string   // (e.g. `feat(core)[RNWY-310]: Add new feature`)
-	Type        string   // (e.g. `feat`)
-	Scope       string   // (e.g. `core`)
-	Subject     string   // (e.g. `Add new feature`)
-	JiraIssueId string   // (e.g. `RNWY-310`)
+	Header      string     // (e.g. `feat(core)[RNWY-310]: Add new feature`)
+	Type        string     // (e.g. `feat`)
+	Scope       string     // (e.g. `core`)
+	Subject     string     // (e.g. `Add new feature`)
+	JiraIssueID string     // (e.g. `RNWY-310`)
 	Body        string
 }

--- a/jira.go
+++ b/jira.go
@ -4,6 +4,7 @@ import (
 	agjira "github.com/andygrunwald/go-jira"
 )

+// JiraClient is an HTTP client for Jira
 type JiraClient interface {
 	GetJiraIssue(id string) (*agjira.Issue, error)
 }
@ -14,11 +15,12 @@ type jiraClient struct {
 	url      string
 }

+// NewJiraClient returns an instance of JiraClient
 func NewJiraClient(config *Config) JiraClient {
 	return jiraClient{
 		username: config.Options.JiraUsername,
-		token: config.Options.JiraToken,
-		url: config.Options.JiraUrl,
+		token:    config.Options.JiraToken,
+		url:      config.Options.JiraURL,
 	}
 }

--- a/jira_test.go
+++ b/jira_test.go
@ -1,14 +1,15 @@
 package chglog

 import (
-	"github.com/stretchr/testify/assert"
 	"testing"
+
+	"github.com/stretchr/testify/assert"
 )

 func TestJira(t *testing.T) {
 	assert := assert.New(t)

-	config := &Config {
+	config := &Config{
 		Options: &Options{
 			Processor:                   nil,
 			NextTag:                     "",
@ -29,7 +30,7 @@ func TestJira(t *testing.T) {
 			NoteKeywords:                nil,
 			JiraUsername:                "uuu",
 			JiraToken:                   "ppp",
-			JiraUrl:                     "http://jira.com",
+			JiraURL:                     "http://jira.com",
 			JiraTypeMaps:                nil,
 			JiraIssueDescriptionPattern: "",
 		},
--- a/logger.go
+++ b/logger.go
@ -7,7 +7,7 @@ import (
 	"regexp"

 	"github.com/fatih/color"
-	emoji "github.com/kyokomi/emoji/v2"
+	"github.com/kyokomi/emoji/v2"
 )

 // Logger ...
@ -26,7 +26,7 @@ func NewLogger(stdout, stderr io.Writer, silent, noEmoji bool) *Logger {
 		stderr:  stderr,
 		silent:  silent,
 		noEmoji: noEmoji,
-		reEmoji: regexp.MustCompile(":[\\w\\+_\\-]+:\\s?"),
+		reEmoji: regexp.MustCompile(`:[\w\+_\-]+:\s?`),
 	}
 }

--- a/logger_test.go
+++ b/logger_test.go
@ -6,8 +6,8 @@ import (
 	"testing"

 	"github.com/fatih/color"
-	"github.com/stretchr/testify/assert"
 	emoji "github.com/kyokomi/emoji/v2"
+	"github.com/stretchr/testify/assert"
 )

 func TestLoggerLogSilent(t *testing.T) {
@ -40,7 +40,7 @@ func TestLoggerLogNoEmoji(t *testing.T) {
 	stderr := &bytes.Buffer{}
 	logger := NewLogger(stdout, stderr, false, true)
 	logger.Log(":+1:Hello, World! :)")
-	assert.Equal(fmt.Sprint("Hello, World! :)\n"), stdout.String())
+	assert.Equal(fmt.Sprint("Hello, World! :)\n"), stdout.String()) //nolint:gosimple
 }

 func TestLoggerError(t *testing.T) {
--- a/processor.go
+++ b/processor.go
@ -33,8 +33,8 @@ func (p *GitHubProcessor) Bootstrap(config *Config) {
 		p.Host = strings.TrimRight(p.Host, "/")
 	}

-	p.reMention = regexp.MustCompile("@(\\w+)")
-	p.reIssue = regexp.MustCompile("(?i)(#|gh-)(\\d+)")
+	p.reMention = regexp.MustCompile(`@(\w+)`)
+	p.reIssue = regexp.MustCompile(`(?i)(#|gh-)(\d+)`)
 }

 // ProcessCommit ...
@ -88,8 +88,8 @@ func (p *GitLabProcessor) Bootstrap(config *Config) {
 		p.Host = strings.TrimRight(p.Host, "/")
 	}

-	p.reMention = regexp.MustCompile("@(\\w+)")
-	p.reIssue = regexp.MustCompile("(?i)#(\\d+)")
+	p.reMention = regexp.MustCompile(`@(\w+)`)
+	p.reIssue = regexp.MustCompile(`(?i)#(\d+)`)
 }

 // ProcessCommit ...
@ -143,8 +143,8 @@ func (p *BitbucketProcessor) Bootstrap(config *Config) {
 		p.Host = strings.TrimRight(p.Host, "/")
 	}

-	p.reMention = regexp.MustCompile("@(\\w+)")
-	p.reIssue = regexp.MustCompile("(?i)#(\\d+)")
+	p.reMention = regexp.MustCompile(`@(\w+)`)
+	p.reIssue = regexp.MustCompile(`(?i)#(\d+)`)
 }

 // ProcessCommit ...
--- a/processor_test.go
+++ b/processor_test.go
@ -27,7 +27,7 @@ func TestGitHubProcessor(t *testing.T) {
 multiline [#789](https://example.com/issues/789)
 [@foo](https://github.com/foo), [@bar](https://github.com/bar)`,
 			Notes: []*Note{
-				&Note{
+				{
 					Body: `issue1 [#11](https://example.com/issues/11)
 issue2 [#22](https://example.com/issues/22)
 [gh-56](https://example.com/issues/56) hoge fuga`,
@ -42,7 +42,7 @@ issue2 [#22](https://example.com/issues/22)
 multiline #789
@foo, @bar`,
 				Notes: []*Note{
-					&Note{
+					{
 						Body: `issue1 #11
 issue2 #22
 gh-56 hoge fuga`,
@ -89,7 +89,7 @@ func TestGitLabProcessor(t *testing.T) {
 multiline [#789](https://example.com/issues/789)
 [@foo](https://gitlab.com/foo), [@bar](https://gitlab.com/bar)`,
 			Notes: []*Note{
-				&Note{
+				{
 					Body: `issue1 [#11](https://example.com/issues/11)
 issue2 [#22](https://example.com/issues/22)
 gh-56 hoge fuga`,
@ -104,7 +104,7 @@ gh-56 hoge fuga`,
 multiline #789
@foo, @bar`,
 				Notes: []*Note{
-					&Note{
+					{
 						Body: `issue1 #11
 issue2 #22
 gh-56 hoge fuga`,
@ -151,7 +151,7 @@ func TestBitbucketProcessor(t *testing.T) {
 multiline [#789](https://example.com/issues/789/)
 [@foo](https://bitbucket.org/foo/), [@bar](https://bitbucket.org/bar/)`,
 			Notes: []*Note{
-				&Note{
+				{
 					Body: `issue1 [#11](https://example.com/issues/11/)
 issue2 [#22](https://example.com/issues/22/)
 gh-56 hoge fuga`,
@ -166,7 +166,7 @@ gh-56 hoge fuga`,
 multiline #789
@foo, @bar`,
 				Notes: []*Note{
-					&Note{
+					{
 						Body: `issue1 #11
 issue2 #22
 gh-56 hoge fuga`,
--- a/tag_reader.go
+++ b/tag_reader.go
@ -12,7 +12,6 @@ import (

 type tagReader struct {
 	client    gitcmd.Client
-	format    string
 	separator string
 	reFilter  *regexp.Regexp
 }
@ -36,7 +35,7 @@ func (r *tagReader) ReadAll() ([]*Tag, error) {
 	tags := []*Tag{}

 	if err != nil {
-		return tags, fmt.Errorf("failed to get git-tag: %s", err.Error())
+		return tags, fmt.Errorf("failed to get git-tag: %w", err)
 	}

 	lines := strings.Split(out, "\n")
--- a/tag_reader_test.go
+++ b/tag_reader_test.go
@ -33,7 +33,7 @@ func TestTagReader(t *testing.T) {

 	assert.Equal(
 		[]*Tag{
-			&Tag{
+			{
 				Name:    "hoge_fuga",
 				Subject: "Invalid semver tag name",
 				Date:    time.Date(2018, 3, 12, 12, 30, 10, 0, time.UTC),
@ -44,7 +44,7 @@ func TestTagReader(t *testing.T) {
 					Date:    time.Date(2018, 2, 3, 12, 30, 10, 0, time.UTC),
 				},
 			},
-			&Tag{
+			{
 				Name:    "5.0.0-rc.0",
 				Subject: "Release 5.0.0-rc.0",
 				Date:    time.Date(2018, 2, 3, 12, 30, 10, 0, time.UTC),
@ -59,7 +59,7 @@ func TestTagReader(t *testing.T) {
 					Date:    time.Date(2018, 2, 2, 10, 0, 40, 0, time.UTC),
 				},
 			},
-			&Tag{
+			{
 				Name:    "4.4.4",
 				Subject: "Release 4.4.4",
 				Date:    time.Date(2018, 2, 2, 10, 0, 40, 0, time.UTC),
@ -74,7 +74,7 @@ func TestTagReader(t *testing.T) {
 					Date:    time.Date(2018, 2, 2, 0, 0, 0, 0, time.UTC),
 				},
 			},
-			&Tag{
+			{
 				Name:    "4.4.3",
 				Subject: "This is tag subject",
 				Date:    time.Date(2018, 2, 2, 0, 0, 0, 0, time.UTC),
@ -89,7 +89,7 @@ func TestTagReader(t *testing.T) {
 					Date:    time.Date(2018, 2, 1, 0, 0, 0, 0, time.UTC),
 				},
 			},
-			&Tag{
+			{
 				Name:    "v2.0.4-beta.1",
 				Subject: "Release v2.0.4-beta.1",
 				Date:    time.Date(2018, 2, 1, 0, 0, 0, 0, time.UTC),
@ -104,11 +104,11 @@ func TestTagReader(t *testing.T) {
 		actual,
 	)

-	actual_filtered, err_filtered := newTagReader(client, "^v").ReadAll()
-	assert.Nil(err_filtered)
+	actualFiltered, errFiltered := newTagReader(client, "^v").ReadAll()
+	assert.Nil(errFiltered)
 	assert.Equal(
 		[]*Tag{
-			&Tag{
+			{
 				Name:     "v2.0.4-beta.1",
 				Subject:  "Release v2.0.4-beta.1",
 				Date:     time.Date(2018, 2, 1, 0, 0, 0, 0, time.UTC),
@ -116,6 +116,6 @@ func TestTagReader(t *testing.T) {
 				Previous: nil,
 			},
 		},
-		actual_filtered,
+		actualFiltered,
 	)
 }
--- a/tag_selector.go
+++ b/tag_selector.go
@ -19,14 +19,16 @@ func (s *tagSelector) Select(tags []*Tag, query string) ([]*Tag, string, error)
 	case 2:
 		old := tokens[0]
 		new := tokens[1]
-		if old == "" && new == "" {
+		switch {
+		case old == "" && new == "":
 			return nil, "", nil
-		} else if old == "" {
+		case old == "":
 			return s.selectBeforeTags(tags, new)
-		} else if new == "" {
+		case new == "":
 			return s.selectAfterTags(tags, old)
+		default:
+			return s.selectRangeTags(tags, tokens[0], tokens[1])
 		}
-		return s.selectRangeTags(tags, tokens[0], tokens[1])
 	}

 	return nil, "", errFailedQueryParse
@ -76,7 +78,8 @@ func (*tagSelector) selectBeforeTags(tags []*Tag, token string) ([]*Tag, string,
 }

 func (*tagSelector) selectAfterTags(tags []*Tag, token string) ([]*Tag, string, error) {
-	var (
+	// NOTE(clok): the res slice can range in size based on the token passed in.
+	var ( //nolint:prealloc
 		res  []*Tag
 		from string
 	)
--- a/tag_selector_test.go
+++ b/tag_selector_test.go
@ -12,51 +12,51 @@ func TestTagSelector(t *testing.T) {
 	selector := newTagSelector()

 	fixtures := []*Tag{
-		&Tag{Name: "2.2.12-rc.12"},
-		&Tag{Name: "2.1.0"},
-		&Tag{Name: "v2.0.0-beta.1"},
-		&Tag{Name: "v1.2.9"},
-		&Tag{Name: "v1.0.0"},
+		{Name: "2.2.12-rc.12"},
+		{Name: "2.1.0"},
+		{Name: "v2.0.0-beta.1"},
+		{Name: "v1.2.9"},
+		{Name: "v1.0.0"},
 	}

 	table := map[string][]string{
 		// Single
-		"2.2.12-rc.12": []string{
+		"2.2.12-rc.12": {
 			"2.2.12-rc.12",
 			"2.1.0",
 		},
-		"v2.0.0-beta.1": []string{
+		"v2.0.0-beta.1": {
 			"v2.0.0-beta.1",
 			"v1.2.9",
 		},
-		"v1.0.0": []string{
+		"v1.0.0": {
 			"v1.0.0",
 			"",
 		},
 		// ~ <tag>
-		"..2.1.0": []string{
+		"..2.1.0": {
 			"2.1.0",
 			"v2.0.0-beta.1",
 			"v1.2.9",
 			"v1.0.0",
 			"",
 		},
-		"..v1.0.0": []string{
+		"..v1.0.0": {
 			"v1.0.0",
 			"",
 		},
 		// <tag> ~
-		"v2.0.0-beta.1..": []string{
+		"v2.0.0-beta.1..": {
 			"2.2.12-rc.12",
 			"2.1.0",
 			"v2.0.0-beta.1",
 			"v1.2.9",
 		},
-		"2.2.12-rc.12..": []string{
+		"2.2.12-rc.12..": {
 			"2.2.12-rc.12",
 			"2.1.0",
 		},
-		"v1.0.0..": []string{
+		"v1.0.0..": {
 			"2.2.12-rc.12",
 			"2.1.0",
 			"v2.0.0-beta.1",
@ -65,7 +65,7 @@ func TestTagSelector(t *testing.T) {
 			"",
 		},
 		// <tag> ~ <tag>
-		"v1.0.0..2.2.12-rc.12": []string{
+		"v1.0.0..2.2.12-rc.12": {
 			"2.2.12-rc.12",
 			"2.1.0",
 			"v2.0.0-beta.1",
@ -73,13 +73,13 @@ func TestTagSelector(t *testing.T) {
 			"v1.0.0",
 			"",
 		},
-		"v1.0.0..v2.0.0-beta.1": []string{
+		"v1.0.0..v2.0.0-beta.1": {
 			"v2.0.0-beta.1",
 			"v1.2.9",
 			"v1.0.0",
 			"",
 		},
-		"v1.2.9..2.1.0": []string{
+		"v1.2.9..2.1.0": {
 			"2.1.0",
 			"v2.0.0-beta.1",
 			"v1.2.9",