Add new linter canonicalheader (#4672)

.golangci.next.reference.yml

@@ -2525,6 +2525,7 @@ linters:
     - asciicheck
     - bidichk
     - bodyclose
+    - canonicalheader
     - containedctx
     - contextcheck
     - copyloopvar
@@ -2639,6 +2640,7 @@ linters:
     - asciicheck
     - bidichk
     - bodyclose
+    - canonicalheader
     - containedctx
     - contextcheck
     - copyloopvar

go.mod

@@ -65,6 +65,7 @@ require (
 	github.com/kulti/thelper v0.6.3
 	github.com/kunwardeep/paralleltest v1.0.10
 	github.com/kyoh86/exportloopref v0.1.11
+	github.com/lasiar/canonicalheader v1.0.5
 	github.com/ldez/gomoddirectives v0.2.4
 	github.com/ldez/tagliatelle v0.5.0
 	github.com/leonklingele/grouper v1.1.2

jsonschema/golangci.next.jsonschema.json

@@ -215,6 +215,7 @@
             "asciicheck",
             "bidichk",
             "bodyclose",
+            "canonicalheader",
             "containedctx",
             "contextcheck",
             "copyloopvar",

pkg/golinters/canonicalheader/canonicalheader.go

@@ -0,0 +1,19 @@
+package canonicalheader
+
+import (
+	"github.com/lasiar/canonicalheader"
+	"golang.org/x/tools/go/analysis"
+
+	"github.com/golangci/golangci-lint/pkg/goanalysis"
+)
+
+func New() *goanalysis.Linter {
+	a := canonicalheader.Analyzer
+
+	return goanalysis.NewLinter(
+		a.Name,
+		a.Doc,
+		[]*analysis.Analyzer{a},
+		nil,
+	).WithLoadMode(goanalysis.LoadModeTypesInfo)
+}

pkg/golinters/canonicalheader/canonicalheader_test.go

@@ -0,0 +1,11 @@
+package canonicalheader_test
+
+import (
+	"testing"
+
+	"github.com/golangci/golangci-lint/test/testshared/integration"
+)
+
+func TestFromTestdata(t *testing.T) {
+	integration.RunTestdata(t)
+}

pkg/golinters/canonicalheader/testdata/canonicalheader.go

@@ -0,0 +1,19 @@
+//golangcitest:args -Ecanonicalheader
+package testdata
+
+import "net/http"
+
+func canonicalheader() {
+	v := http.Header{}
+
+	v.Get("Test-HEader")          // want `non-canonical header "Test-HEader", instead use: "Test-Header"`
+	v.Set("Test-HEader", "value") // want `non-canonical header "Test-HEader", instead use: "Test-Header"`
+	v.Add("Test-HEader", "value") // want `non-canonical header "Test-HEader", instead use: "Test-Header"`
+	v.Del("Test-HEader")          // want `non-canonical header "Test-HEader", instead use: "Test-Header"`
+	v.Values("Test-HEader")       // want `non-canonical header "Test-HEader", instead use: "Test-Header"`
+
+	v.Set("Test-Header", "value")
+	v.Add("Test-Header", "value")
+	v.Del("Test-Header")
+	v.Values("Test-Header")
+}

pkg/lint/lintersdb/builder_linter.go

@@ -7,6 +7,7 @@ import (
 	"github.com/golangci/golangci-lint/pkg/golinters/asciicheck"
 	"github.com/golangci/golangci-lint/pkg/golinters/bidichk"
 	"github.com/golangci/golangci-lint/pkg/golinters/bodyclose"
+	"github.com/golangci/golangci-lint/pkg/golinters/canonicalheader"
 	"github.com/golangci/golangci-lint/pkg/golinters/containedctx"
 	"github.com/golangci/golangci-lint/pkg/golinters/contextcheck"
 	"github.com/golangci/golangci-lint/pkg/golinters/copyloopvar"
@@ -154,6 +155,12 @@ func (LinterBuilder) Build(cfg *config.Config) ([]*linter.Config, error) {
 			WithPresets(linter.PresetPerformance, linter.PresetBugs).
 			WithURL("https://github.com/timakin/bodyclose"),
 
+		linter.NewConfig(canonicalheader.New()).
+			WithSince("v1.58.0").
+			WithPresets(linter.PresetStyle).
+			WithLoadForGoAnalysis().
+			WithURL("https://github.com/lasiar/canonicalHeader"),
+
 		linter.NewConfig(containedctx.New()).
 			WithSince("1.44.0").
 			WithLoadForGoAnalysis().