add linting and update go versions in CI

.github/workflows/ci.yml

@@ -8,29 +8,23 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        go-version:
-          - stable
+        go-version: # see https://endoflife.date/go
+          - 1.24.x
+          - 1.23.x
+          - 1.22.x
           - 1.21.x
-          - 1.20.x
-          - 1.19.x
-          - 1.18.x
-          - 1.17.x
-          - 1.16.x
-          - 1.15.x
-          - 1.14.x
-          - 1.13.x
-          - 1.12.x
-          - 1.11.x
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Set up Go ${{ matrix.go-version }}
-      uses: actions/setup-go@v4
+      uses: actions/setup-go@v5
       with:
         go-version: ${{ matrix.go-version }}
 
     - name: Test
       run: |
-        go vet ./...
         go test -tags CI -race ./...
-      env:
-        GOPATH: /home/runner/go
+    - name: golangci-lint
+      uses: golangci/golangci-lint-action@latest
+      with:
+        version: latest
+        args: -v -c .golangci.yaml

.golangci.yaml

@@ -0,0 +1,7 @@
+---
+version: "2"
+run:
+  allow-parallel-runners: true
+linters:
+  disable:
+    - "errcheck"

mage/main.go

@@ -173,7 +173,7 @@ func ParseAndRun(stdout, stderr io.Writer, stdin io.Reader, args []string) int {
 	case None:
 		return Invoke(inv)
 	default:
-		panic(fmt.Errorf("Unknown command type: %v", cmd))
+		panic(fmt.Errorf("unknown command type: %v", cmd))
 	}
 }
 

mage/main_test.go

@@ -920,7 +920,7 @@ func TestOnlyStdLib(t *testing.T) {
 		if err != nil {
 			t.Fatal(err)
 		}
-		if !filepath.HasPrefix(pkg.Dir, build.Default.GOROOT) {
+		if !strings.HasPrefix(pkg.Dir, build.Default.GOROOT) {
 			t.Errorf("import of non-stdlib package: %s", s.Path.Value)
 		}
 	}

mg/deps_test.go

@@ -86,7 +86,7 @@ func TestDepError(t *testing.T) {
 			t.Fatal("expected panic, but didn't get one")
 		}
 		actual := fmt.Sprint(err)
-		if "ouch" != actual {
+		if actual != "ouch" {
 			t.Fatalf(`expected to get "ouch" but got "%s"`, actual)
 		}
 	}()
@@ -103,7 +103,7 @@ func TestDepFatal(t *testing.T) {
 			t.Fatal("expected panic, but didn't get one")
 		}
 		actual := fmt.Sprint(v)
-		if "ouch!" != actual {
+		if actual != "ouch!" {
 			t.Fatalf(`expected to get "ouch!" but got "%s"`, actual)
 		}
 		err, ok := v.(error)
@@ -132,7 +132,7 @@ func TestDepTwoFatal(t *testing.T) {
 		}
 		actual := fmt.Sprint(v)
 		// order is non-deterministic, so check for both orders
-		if "ouch!\nbang!" != actual && "bang!\nouch!" != actual {
+		if actual != "ouch!\nbang!" && actual != "bang!\nouch!" {
 			t.Fatalf(`expected to get "ouch!" and "bang!" but got "%s"`, actual)
 		}
 		err, ok := v.(error)
@@ -157,7 +157,7 @@ func TestDepWithUnhandledFunc(t *testing.T) {
 			t.Fatalf("Expected type error from panic")
 		}
 	}()
-	var NotValid func(string) string = func(a string) string {
+	var NotValid = func(a string) string {
 		return a
 	}
 	Deps(NotValid)

mg/fn_test.go

@@ -51,7 +51,7 @@ func TestFuncCheck(t *testing.T) {
 		t.Error("func is not on a namespace")
 	}
 
-	hasContext, isNamespace, err = checkF(Foo.Bare, nil)
+	_, _, err = checkF(Foo.Bare, nil)
 	if err != nil {
 		t.Error(err)
 	}
@@ -117,11 +117,11 @@ func TestFuncCheck(t *testing.T) {
 	}
 
 	defer func() {
-		if r := recover(); r !=nil {
+		if r := recover(); r != nil {
 			t.Error("expected a nil function argument to be handled gracefully")
 		}
 	}()
-	_, _, err = checkF(nil, []interface{}{1,2})
+	_, _, err = checkF(nil, []interface{}{1, 2})
 	if err == nil {
 		t.Error("expected a nil function argument to be invalid")
 	}

parse/parse.go

@@ -214,7 +214,7 @@ func checkDupes(info *PkgInfo, imports []*Import) error {
 			for _, f := range funcs[alias] {
 				ids = append(ids, f.ID())
 			}
-			return fmt.Errorf("alias %q duplicates existing target(s): %s\n", alias, strings.Join(ids, ", "))
+			return fmt.Errorf("alias %q duplicates existing target(s): %s", alias, strings.Join(ids, ", "))
 		}
 		funcs[alias] = append(funcs[alias], f)
 	}
@@ -792,11 +792,6 @@ func hasContextParam(ft *ast.FuncType) (bool, error) {
 	return true, nil
 }
 
-func hasVoidReturn(ft *ast.FuncType) bool {
-	res := ft.Results
-	return res.NumFields() == 0
-}
-
 func hasErrorReturn(ft *ast.FuncType) (bool, error) {
 	res := ft.Results
 	if res.NumFields() == 0 {
@@ -847,7 +842,7 @@ func funcType(ft *ast.FuncType) (*Function, error) {
 }
 
 func toOneLine(s string) string {
-	return strings.TrimSpace(strings.Replace(s, "\n", " ", -1))
+	return strings.TrimSpace(strings.ReplaceAll(s, "\n", " "))
 }
 
 var argTypes = map[string]string{