feat: deprecate varcheck, deadcode, and structcheck (golangci#3125)

.golangci.yml

@@ -68,7 +68,6 @@ linters:
   disable-all: true
   enable:
     - bodyclose
-    - deadcode
     - depguard
     - dogsled
     - dupl
@@ -93,13 +92,11 @@ linters:
     - noctx
     - nolintlint
     - staticcheck
-    - structcheck
     - stylecheck
     - typecheck
     - unconvert
     - unparam
     - unused
-    - varcheck
     - whitespace
 
   # don't enable:

pkg/lint/lintersdb/manager.go

@@ -320,7 +320,8 @@ func (m Manager) GetAllSupportedLinterConfigs() []*linter.Config {
 			WithSince("v1.0.0").
 			WithLoadForGoAnalysis().
 			WithPresets(linter.PresetUnused).
-			WithURL("https://github.com/remyoudompheng/go-misc/tree/master/deadcode"),
+			WithURL("https://github.com/remyoudompheng/go-misc/tree/master/deadcode").
+			Deprecated("The owner seems to have abandoned the linter.", "v1.49.0", "unused"),
 
 		linter.NewConfig(golinters.NewDepguard(depGuardCfg)).
 			WithSince("v1.4.0").
@@ -714,6 +715,7 @@ func (m Manager) GetAllSupportedLinterConfigs() []*linter.Config {
 			WithLoadForGoAnalysis().
 			WithPresets(linter.PresetUnused).
 			WithURL("https://github.com/opennota/check").
+			Deprecated("The owner seems to have abandoned the linter.", "v1.49.0", "unused").
 			WithNoopFallback(m.cfg),
 
 		linter.NewConfig(golinters.NewStylecheck(stylecheckCfg)).
@@ -786,7 +788,8 @@ func (m Manager) GetAllSupportedLinterConfigs() []*linter.Config {
 			WithSince("v1.0.0").
 			WithLoadForGoAnalysis().
 			WithPresets(linter.PresetUnused).
-			WithURL("https://github.com/opennota/check"),
+			WithURL("https://github.com/opennota/check").
+			Deprecated("The owner seems to have abandoned the linter.", "v1.49.0", "unused"),
 
 		linter.NewConfig(golinters.NewVarnamelen(varnamelenCfg)).
 			WithSince("v1.43.0").
@@ -834,9 +837,7 @@ func (m Manager) GetAllSupportedLinterConfigs() []*linter.Config {
 		golinters.NewStaticcheck(staticcheckCfg).Name(): true,
 		golinters.NewUnused(unusedCfg).Name():           true,
 		golinters.NewGosimple(gosimpleCfg).Name():       true,
-		golinters.NewVarcheck(varcheckCfg).Name():       true,
 		golinters.NewIneffassign().Name():               true,
-		golinters.NewDeadcode().Name():                  true,
 		golinters.NewTypecheck().Name():                 true,
 	}
 	return enableLinterConfigs(lcs, func(lc *linter.Config) bool {

pkg/result/processors/nolint_test.go

@@ -128,16 +128,23 @@ func TestNolintInvalidLinterName(t *testing.T) {
 		{
 			Pos: token.Position{
 				Filename: fileName,
-				Line:     3,
+				Line:     10,
 			},
-			FromLinter: "varcheck",
+			FromLinter: "errcheck",
+		},
+		{
+			Pos: token.Position{
+				Filename: fileName,
+				Line:     13,
+			},
+			FromLinter: "errcheck",
 		},
 		{
 			Pos: token.Position{
 				Filename: fileName,
-				Line:     6,
+				Line:     22,
 			},
-			FromLinter: "deadcode",
+			FromLinter: "ineffassign",
 		},
 	}
 
@@ -244,22 +251,22 @@ func TestIgnoredRangeMatches(t *testing.T) {
 func TestNolintWholeFile(t *testing.T) {
 	fileName := filepath.Join("testdata", "nolint_whole_file.go")
 
-	p := newTestNolintProcessor(nil)
+	p := newTestNolintProcessor(getMockLog())
 	defer p.Finish()
 
 	processAssertEmpty(t, p, result.Issue{
 		Pos: token.Position{
 			Filename: fileName,
-			Line:     4,
+			Line:     9,
 		},
-		FromLinter: "varcheck",
+		FromLinter: "errcheck",
 	})
 	processAssertSame(t, p, result.Issue{
 		Pos: token.Position{
 			Filename: fileName,
-			Line:     4,
+			Line:     14,
 		},
-		FromLinter: "deadcode",
+		FromLinter: "govet",
 	})
 }
 

pkg/result/processors/processor_test.go

@@ -35,17 +35,23 @@ func newIssueFromTextTestCase(text string) result.Issue {
 }
 
 func process(t *testing.T, p Processor, issues ...result.Issue) []result.Issue {
+	t.Helper()
+
 	processedIssues, err := p.Process(issues)
 	assert.NoError(t, err)
 	return processedIssues
 }
 
 func processAssertSame(t *testing.T, p Processor, issues ...result.Issue) {
+	t.Helper()
+
 	processedIssues := process(t, p, issues...)
 	assert.Equal(t, issues, processedIssues)
 }
 
 func processAssertEmpty(t *testing.T, p Processor, issues ...result.Issue) {
+	t.Helper()
+
 	processedIssues := process(t, p, issues...)
 	assert.Empty(t, processedIssues)
 }

pkg/result/processors/testdata/nolint_bad_names.go

@@ -1,8 +1,25 @@
 package testdata
 
-var nolintUnknownLinter1 bool //nolint:bad1,deadcode,varcheck,megacheck
+import "math"
 
-//nolint:bad2,deadcode,megacheck
-func nolintUnknownLinter2() {
+func RetErr() error {
+	return nil
+}
+
+func MissedErrorCheck() {
+	RetErr() //nolint:bad1,errcheck
+}
+
+//nolint:bad2,errcheck
+func MissedErrorCheck2() {
+	RetErr()
+}
 
+func _() {
+	x := math.MinInt8
+	for {
+		_ = x
+		x = 0 //nolint:bad1,ineffassign
+		x = 0
+	}
 }

pkg/result/processors/testdata/nolint_whole_file.go

@@ -1,4 +1,14 @@
-//nolint: varcheck
+//nolint:errcheck
 package testdata
 
-var nolintVarcheck int
+func RetError() error {
+	return nil
+}
+
+func MissedErrorCheck1() {
+	RetErr()
+}
+
+func jo(v, w bool) bool {
+	return v == w || v == w
+}

test/bench/bench_test.go

@@ -47,12 +47,7 @@ func prepareGithubProject(owner, name string) func(*testing.B) {
 
 func getBenchLintersArgsNoMegacheck() []string {
 	return []string{
-		"--enable=deadcode",
 		"--enable=gocyclo",
-		"--enable=golint",
-		"--enable=varcheck",
-		"--enable=structcheck",
-		"--enable=maligned",
 		"--enable=errcheck",
 		"--enable=dupl",
 		"--enable=ineffassign",

test/run_test.go

@@ -251,16 +251,16 @@ func TestSortedResults(t *testing.T) {
 		{
 			opt: "--sort-results=false",
 			want: strings.Join([]string{
-				"testdata/sort_results/main.go:12:5: `db` is unused (deadcode)",
 				"testdata/sort_results/main.go:15:13: Error return value is not checked (errcheck)",
+				"testdata/sort_results/main.go:12:5: var `db` is unused (unused)",
 				"testdata/sort_results/main.go:8:6: func `returnError` is unused (unused)",
 			}, "\n"),
 		},
 		{
 			opt: "--sort-results=true",
 			want: strings.Join([]string{
 				"testdata/sort_results/main.go:8:6: func `returnError` is unused (unused)",
-				"testdata/sort_results/main.go:12:5: `db` is unused (deadcode)",
+				"testdata/sort_results/main.go:12:5: var `db` is unused (unused)",
 				"testdata/sort_results/main.go:15:13: Error return value is not checked (errcheck)",
 			}, "\n"),
 		},
@@ -435,17 +435,6 @@ func TestSkippedDirsTestdata(t *testing.T) {
 		ExpectNoIssues() // all was skipped because in testdata
 }
 
-func TestDeadcodeNoFalsePositivesInMainPkg(t *testing.T) {
-	testshared.NewRunnerBuilder(t).
-		WithNoConfig().
-		WithArgs("--disable-all", "-Edeadcode").
-		WithTargetPath(testdataDir, "deadcode_main_pkg").
-		Runner().
-		Install().
-		Run().
-		ExpectNoIssues()
-}
-
 func TestIdentifierUsedOnlyInTests(t *testing.T) {
 	testshared.NewRunnerBuilder(t).
 		WithNoConfig().

test/testdata/deadcode.go

@@ -1,4 +1,4 @@
-//golangcitest:args -Edeadcode
+//golangcitest:args -Edeadcode --internal-cmd-test
 package testdata
 
 var y int

test/testdata/gomodguard.go

@@ -12,13 +12,13 @@ import (
 // Something just some struct
 type Something struct{}
 
-func aAllowedImport() { //nolint:deadcode,unused
+func aAllowedImport() { //nolint:unused
 	mfile, _ := modfile.Parse("go.mod", []byte{}, nil)
 
 	log.Println(mfile)
 }
 
-func aBlockedImport() { //nolint:deadcode,unused
+func aBlockedImport() { //nolint:unused
 	data := []byte{}
 	something := Something{}
 	_ = yaml.Unmarshal(data, &something)

test/testdata/nolintlint.go

@@ -8,7 +8,7 @@ import "fmt"
 func Foo() {
 	fmt.Println("not specific")         //nolint // want "directive `.*` should mention specific linter such as `//nolint:my-linter`"
 	fmt.Println("not machine readable") // nolint // want "directive `.*`  should be written as `//nolint`"
-	fmt.Println("extra spaces")         //  nolint:deadcode // because // want "directive `.*` should not have more than one leading space"
+	fmt.Println("extra spaces")         //  nolint:unused // because // want "directive `.*` should not have more than one leading space"
 
 	// test expanded range
 	//nolint:misspell // deliberate misspelling to trigger nolintlint

test/testdata/varcheck.go

@@ -1,4 +1,4 @@
-//golangcitest:args -Evarcheck
+//golangcitest:args -Evarcheck --internal-cmd-test
 package testdata
 
 var v string // want "`v` is unused"