feat: add validjson linter

.golangci.reference.yml

@@ -2090,6 +2090,7 @@ linters:
     - unparam
     - unused
     - usestdlibvars
+    - validjson
     - varcheck
     - varnamelen
     - wastedassign
@@ -2200,6 +2201,7 @@ linters:
     - unparam
     - unused
     - usestdlibvars
+    - validjson
     - varcheck
     - varnamelen
     - wastedassign

go.mod

@@ -65,6 +65,7 @@ require (
 	github.com/maratori/testableexamples v1.0.0
 	github.com/maratori/testpackage v1.1.0
 	github.com/matoous/godox v0.0.0-20210227103229-6504466cf951 // v1.0
+	github.com/matthewloring/validjson v0.2.0
 	github.com/mattn/go-colorable v0.1.13
 	github.com/mbilski/exhaustivestruct v1.2.0
 	github.com/mgechev/revive v1.2.5

pkg/golinters/validjson.go

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

pkg/lint/lintersdb/manager.go

@@ -835,6 +835,11 @@ func (m Manager) GetAllSupportedLinterConfigs() []*linter.Config {
 			WithPresets(linter.PresetStyle).
 			WithURL("https://github.com/sashamelentyev/usestdlibvars"),
 
+		linter.NewConfig(golinters.NewValidJSON()).
+			WithSince("v1.51.0").
+			WithPresets(linter.PresetBugs).
+			WithURL("https://github.com/matthewloring/validjson"),
+
 		linter.NewConfig(golinters.NewVarcheck(varcheckCfg)).
 			WithSince("v1.0.0").
 			WithLoadForGoAnalysis().

test/testdata/validjson.go

@@ -0,0 +1,42 @@
+//golangcitest:args -Evalidjson
+package testdata
+
+type Key struct {
+	A, B string
+}
+
+type StrAlias string
+
+type ChanAlias chan<- int
+
+type Textable [2]byte
+
+func (Textable) MarshalText() ([]byte, error) {
+	return nil, nil
+}
+
+func (*Textable) UnmarshalText(_ []byte) error {
+	return nil
+}
+
+type ValidJsonTest struct {
+	A int                           `json:"A"`
+	B int                           `json:"B,omitempty"`
+	C int                           `json:",omitempty"`
+	D int                           `json:"-"`
+	E chan<- int                    `json:"E"` // want "struct field has json tag but non-serializable type chan<- int"
+	F chan<- int                    `json:"-"`
+	G chan<- int                    `json:"-,"` // want "struct field has json tag but non-serializable type chan<- int"
+	H ChanAlias                     `json:"H"`  // want "struct field has json tag but non-serializable type command-line-arguments.ChanAlias"
+	I map[int]int                   `json:"I"`
+	J map[int64]int                 `json:"J"`
+	K map[Key]int                   `json:"K"` // want "struct field has json tag but non-serializable type"
+	L map[struct{ A, B string }]int `json:"L"` // want "struct field has json tag but non-serializable type"
+	M map[string]int                `json:"M"`
+	N map[StrAlias]int              `json:"N"`
+	O func()                        `json:"O"` // want "struct field has json tag but non-serializable type func()"
+	P complex64                     `json:"P"` // want "struct field has json tag but non-serializable type complex64"
+	Q complex128                    `json:"Q"` // want "struct field has json tag but non-serializable type complex128"
+	R StrAlias                      `json:"R"`
+	S map[Textable]int              `json:"S"`
+}