Brush all the lint off this code I wrote in a haze

README.md

@@ -5,6 +5,7 @@ TODO:
 * [x] Make a `.drone.yml` that's sufficient for building an image
 * [x] Make a `Dockerfile` that's sufficient for launching the built image
 * [x] Make `cmd/drone-helm/main.go` actually invoke `helm`
+* [x] Make `golint` part of the build process (and make it pass)
 * [ ] Flesh out `helm upgrade` until it's capable of working
 * [ ] Implement `helm lint`
 * [ ] Implement `helm delete`

go.mod

@@ -6,4 +6,6 @@ require (
 	github.com/golang/mock v1.3.1
 	github.com/kelseyhightower/envconfig v1.4.0
 	github.com/stretchr/testify v1.4.0
+	golang.org/x/lint v0.0.0-20191125180803-fdd1cda4f05f // indirect
+	golang.org/x/tools v0.0.0-20191206204035-259af5ff87bd // indirect
 )

go.sum

@@ -10,12 +10,20 @@ github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+
 github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/lint v0.0.0-20191125180803-fdd1cda4f05f h1:J5lckAjkw6qYlOZNj90mLYNTEKDvWeuc1yieZ8qUzUE=
+golang.org/x/lint v0.0.0-20191125180803-fdd1cda4f05f/go.mod h1:5qLYkcX4OjUUV8bRuDixDT3tpyyb+LUpUlRWLxfhWrs=
 golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/tools v0.0.0-20190425150028-36563e24a262 h1:qsl9y/CJx34tuA7QCPNp86JNJe4spst6Ff8MjvPUdPg=
 golang.org/x/tools v0.0.0-20190425150028-36563e24a262/go.mod h1:RgjU9mgBXZiqYHBnxXauZ1Gv1EHHAz9KjViQ78xBX0Q=
+golang.org/x/tools v0.0.0-20191125144606-a911d9008d1f h1:kDxGY2VmgABOe55qheT/TFqUMtcTHnomIPS1iv3G4Ms=
+golang.org/x/tools v0.0.0-20191125144606-a911d9008d1f/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/tools v0.0.0-20191206204035-259af5ff87bd h1:Zc7EU2PqpsNeIfOoVA7hvQX4cS3YDJEs5KlfatT3hLo=
+golang.org/x/tools v0.0.0-20191206204035-259af5ff87bd/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=

internal/helm/config.go

@@ -5,9 +5,14 @@ import (
 	"strings"
 )
 
+// The Config struct captures the `settings` and `environment` blocks inthe application's drone
+// config. Configuration in drone's `settings` block arrives as uppercase env vars matching the
+// config key, prefixed with `PLUGIN_`. Config from the `environment` block is *not* prefixed; any
+// keys that are likely to be in that block (i.e. things that use `from_secret` need an explicit
+// `envconfig:` tag so that envconfig will look for a non-prefixed env var.
 type Config struct {
 	// Configuration for drone-helm itself
-	Command            HelmCommand `envconfig:"HELM_COMMAND"`      // Helm command to run
+	Command            helmCommand `envconfig:"HELM_COMMAND"`      // Helm command to run
 	DroneEvent         string      `envconfig:"DRONE_BUILD_EVENT"` // Drone event that invoked this plugin.
 	UpdateDependencies bool        `split_words:"true"`            // call `helm dependency update` before the main command
 	Repos              []string    `envconfig:"HELM_REPOS"`        // call `helm repo add` before the main command
@@ -37,14 +42,14 @@ type Config struct {
 	Force        bool   `` //
 }
 
-type HelmCommand string
+type helmCommand string
 
-// HelmCommand.Decode checks the given value against the list of known commands and generates a helpful error if the command is unknown.
+// helmCommand.Decode checks the given value against the list of known commands and generates a helpful error if the command is unknown.
-func (cmd *HelmCommand) Decode(value string) error {
+func (cmd *helmCommand) Decode(value string) error {
 	known := []string{"upgrade", "delete", "lint", "help"}
 	for _, c := range known {
 		if value == c {
-			*cmd = HelmCommand(value)
+			*cmd = helmCommand(value)
 			return nil
 		}
 	}
@@ -53,6 +58,6 @@ func (cmd *HelmCommand) Decode(value string) error {
 		return nil
 	}
 	known[len(known)-1] = fmt.Sprintf("or %s", known[len(known)-1])
-	return fmt.Errorf("Unknown command '%s'. If specified, command must be %s.",
+	return fmt.Errorf("unknown command '%s'. If specified, command must be %s",
 		value, strings.Join(known, ", "))
 }

internal/helm/config_test.go

@@ -14,7 +14,7 @@ func TestConfigTestSuite(t *testing.T) {
 }
 
 func (suite *ConfigTestSuite) TestHelmCommandDecodeSuccess() {
-	cmd := HelmCommand("")
+	cmd := helmCommand("")
 	err := cmd.Decode("upgrade")
 	suite.Require().Nil(err)
 
@@ -22,7 +22,7 @@ func (suite *ConfigTestSuite) TestHelmCommandDecodeSuccess() {
 }
 
 func (suite *ConfigTestSuite) TestHelmCommandDecodeFailure() {
-	cmd := HelmCommand("")
+	cmd := helmCommand("")
 	err := cmd.Decode("execute order 66")
-	suite.EqualError(err, "Unknown command 'execute order 66'. If specified, command must be upgrade, delete, lint, or help.")
+	suite.EqualError(err, "unknown command 'execute order 66'. If specified, command must be upgrade, delete, lint, or help")
 }

internal/helm/plan.go

@@ -5,14 +5,17 @@ import (
 	"github.com/pelotech/drone-helm3/internal/run"
 )
 
+// A Step is one step in the plan.
 type Step interface {
 	Run() error
 }
 
+// A Plan is a series of steps to perform.
 type Plan struct {
 	steps []Step
 }
 
+// NewPlan makes a plan for running a helm operation.
 func NewPlan(cfg Config) (*Plan, error) {
 	p := Plan{}
 	switch cfg.Command {
@@ -44,6 +47,7 @@ func NewPlan(cfg Config) (*Plan, error) {
 	return &p, nil
 }
 
+// Execute runs each step in the plan, aborting and reporting on error
 func (p *Plan) Execute() error {
 	for _, step := range p.steps {
 		if err := step.Run(); err != nil {

internal/run/cmd.go

@@ -7,7 +7,7 @@ import (
 	"syscall"
 )
 
-const HELM_BIN = "/usr/bin/helm"
+const helmBin = "/usr/bin/helm"
 
 // The cmd interface provides a generic form of exec.Cmd so that it can be mocked out in tests.
 type cmd interface {
@@ -43,7 +43,7 @@ type execCmd struct {
 	*exec.Cmd
 }
 
-var Command = func(path string, args ...string) cmd {
+var command = func(path string, args ...string) cmd {
 	return &execCmd{
 		Cmd: exec.Command(path, args...),
 	}

internal/run/help.go

@@ -4,18 +4,21 @@ import (
 	"os"
 )
 
+// Help is a step in a helm Plan that calls `helm help`.
 type Help struct {
 	cmd cmd
 }
 
+// Run launches the command.
 func (h *Help) Run() error {
 	return h.cmd.Run()
 }
 
+// NewHelp returns a new Help.
 func NewHelp() *Help {
 	h := Help{}
 
-	h.cmd = Command(HELM_BIN, "help")
+	h.cmd = command(helmBin, "help")
 	h.cmd.Stdout(os.Stdout)
 	h.cmd.Stderr(os.Stderr)
 

internal/run/help_test.go

@@ -11,14 +11,14 @@ func TestHelp(t *testing.T) {
 	defer ctrl.Finish()
 
 	mCmd := NewMockcmd(ctrl)
-	originalCommand := Command
+	originalCommand := command
 
-	Command = func(path string, args ...string) cmd {
+	command = func(path string, args ...string) cmd {
-		assert.Equal(t, HELM_BIN, path)
+		assert.Equal(t, helmBin, path)
 		assert.Equal(t, []string{"help"}, args)
 		return mCmd
 	}
-	defer func() { Command = originalCommand }()
+	defer func() { command = originalCommand }()
 
 	mCmd.EXPECT().
 		Stdout(gomock.Any())

internal/run/upgrade.go

@@ -4,21 +4,24 @@ import (
 	"os"
 )
 
+// Upgrade is a step in a helm Plan that calls `helm upgrade`.
 type Upgrade struct {
 	Chart   string
 	Release string
 	cmd     cmd
 }
 
+// Run launches the command.
 func (u *Upgrade) Run() error {
 	return u.cmd.Run()
 }
 
+// NewUpgrade creates a new Upgrade.
 func NewUpgrade(release, chart string) *Upgrade {
 	u := Upgrade{
 		Chart:   chart,
 		Release: release,
-		cmd:     Command(HELM_BIN, "upgrade", "--install", release, chart),
+		cmd:     command(helmBin, "upgrade", "--install", release, chart),
 	}
 
 	u.cmd.Stdout(os.Stdout)

internal/run/upgrade_test.go

@@ -11,15 +11,15 @@ func TestNewUpgrade(t *testing.T) {
 	defer ctrl.Finish()
 
 	mCmd := NewMockcmd(ctrl)
-	originalCommand := Command
+	originalCommand := command
 
-	Command = func(path string, args ...string) cmd {
+	command = func(path string, args ...string) cmd {
-		assert.Equal(t, HELM_BIN, path)
+		assert.Equal(t, helmBin, path)
 		assert.Equal(t, []string{"upgrade", "--install", "jonas_brothers_only_human", "at40"}, args)
 
 		return mCmd
 	}
-	defer func() { Command = originalCommand }()
+	defer func() { command = originalCommand }()
 
 	mCmd.EXPECT().
 		Stdout(gomock.Any())