ci(lint): setup golangci-lint

Release-As: 0.0.4

.github/workflows/ci.yml

@@ -17,6 +17,21 @@ jobs:
         run: |
           ./bin/macos-battery-exporter -v
 
+  lint:
+    name: Lint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v5
+        with:
+          go-version: "1.21"
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@v3
+        with:
+          version: v1.55
+        env:
+          VERBOSE: "true"
+
   release-please:
     runs-on: ubuntu-latest
     if: github.ref == 'refs/heads/main'
@@ -35,7 +50,7 @@ jobs:
       - uses: actions/checkout@v4
         with:
           fetch-depth: 0
-      - uses: actions/setup-go@v4
+      - uses: actions/setup-go@v5
         with:
           go-version: "1.21"
       - name: Run GoReleaser

.golangci.yml

@@ -0,0 +1,87 @@
+linters-settings:
+  funlen:
+    lines: 300
+    statements: 450
+  golint:
+    min-confidence: 0
+  govet:
+    enable-all: true
+    disable:
+      - fieldalignment
+      - shadow
+  lll:
+    line-length: 80
+    tab-width: 4
+  maligned:
+    suggest-new: true
+  misspell:
+    locale: US
+
+linters:
+  disable-all: true
+  enable:
+    - asciicheck
+    - bodyclose
+    - durationcheck
+    - errcheck
+    - errorlint
+    - exhaustive
+    - exportloopref
+    - funlen
+    - gochecknoinits
+    - goconst
+    - gocritic
+    - godot
+    - goimports
+    - gomodguard
+    - goprintffuncname
+    - gosec
+    - gosimple
+    - govet
+    - importas
+    - ineffassign
+    - lll
+    - misspell
+    - nakedret
+    - nilerr
+    - noctx
+    - nolintlint
+    - prealloc
+    - predeclared
+    - revive
+    - staticcheck
+    - typecheck
+    - unconvert
+    - unparam
+    - unused
+    - whitespace
+
+issues:
+  exclude:
+    - Using the variable on range scope `tt` in function literal
+    - Using the variable on range scope `tc` in function literal
+  exclude-rules:
+    - path: "_test\\.go"
+      linters:
+        - funlen
+        - dupl
+    - source: "^//go:generate "
+      linters:
+        - lll
+    - source: "`env:"
+      linters:
+        - lll
+    - source: "`json:"
+      linters:
+        - lll
+    - source: "`xml:"
+      linters:
+        - lll
+    - source: "`yaml:"
+      linters:
+        - lll
+
+run:
+  timeout: 2m
+  allow-parallel-runners: true
+  modules-download-mode: readonly

battery/battery.go

@@ -15,12 +15,12 @@ type Battery struct {
 	// BuiltIn indicates if the battery is built-in or not.
 	BuiltIn bool
 
-	// ChargeRateAmps is the current charge rate in mAh. Negative values indicate
-	// discharge, positive values indicate charging.
+	// ChargeRateAmps is the current charge rate in mAh. Negative values
+	// indicate discharge, positive values indicate charging.
 	ChargeRateAmps int64
 
-	// ChargeRateWatts is the current charge rate in mWh. Negative values indicate
-	// discharge, positive values indicate charging.
+	// ChargeRateWatts is the current charge rate in mWh. Negative values
+	// indicate discharge, positive values indicate charging.
 	ChargeRateWatts float64
 
 	// CurrentCapacityAmps is the current battery capacity in mAh.
@@ -76,6 +76,7 @@ type Battery struct {
 func newBattery(b *batteryRaw) *Battery {
 	volts := float64(b.Voltage) / 1000
 
+	//nolint:lll
 	return &Battery{
 		BatteryCellDisconnectCount: b.BatteryCellDisconnectCount,
 		BuiltIn:                    b.BuiltIn,
@@ -101,29 +102,31 @@ func newBattery(b *batteryRaw) *Battery {
 }
 
 func Get() (*Battery, error) {
-	batteriesRaw, err := getAllRaw()
+	raw, err := getAllRaw()
 	if err != nil {
 		return nil, err
 	}
 
-	return newBattery(batteriesRaw[0]), nil
+	return newBattery(raw[0]), nil
 }
 
 func GetAll() ([]*Battery, error) {
-	batteriesRaw, err := getAllRaw()
+	raw, err := getAllRaw()
 	if err != nil {
 		return nil, err
 	}
 
 	batteries := []*Battery{}
-	for _, b := range batteriesRaw {
+	for _, b := range raw {
 		batteries = append(batteries, newBattery(b))
 	}
 
 	return batteries, nil
 }
 
-// roundTo rounds a float64 to 'places' decimal places
+// roundTo rounds a float64 to 'places' decimal places.
+//
+//nolint:unparam
 func roundTo(value float64, places int) float64 {
 	shift := math.Pow(10, float64(places))
 	return math.Round(value*shift) / shift

main.go

@@ -88,10 +88,10 @@ func mainE() error {
 
 	if *outputFlag != "" {
 		return writeToFile(sb.String(), *outputFlag)
-	} else {
-		fmt.Print(sb.String())
 	}
 
+	fmt.Print(sb.String())
+
 	return nil
 }
 

prom/collector.go

@@ -367,7 +367,9 @@ func boolToFloat64(b bool) float64 {
 	return 0
 }
 
-// roundTo rounds a float64 to 'places' decimal places
+// roundTo rounds a float64 to 'places' decimal places.
+//
+//nolint:unparam
 func roundTo(value float64, places int) float64 {
 	shift := math.Pow(10, float64(places))
 	return math.Round(value*shift) / shift