.goreleaser.yml

@@ -29,3 +29,5 @@ release:
   github:
     owner: breml
     name: errchkjson
+gomod:
+  proxy: true

cmd/errchkjson/main.go

@@ -1,11 +1,42 @@
 package main
 
 import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"runtime"
+	"runtime/debug"
+
 	"github.com/breml/errchkjson"
 
 	"golang.org/x/tools/go/analysis/singlechecker"
 )
 
+var (
+	version = "development"
+	commit  = ""
+	date    = ""
+)
+
 func main() {
+	errchkjson.Version = buildVersion()
+
 	singlechecker.Main(errchkjson.NewAnalyzer())
 }
+
+func buildVersion() string {
+	result := fmt.Sprintf("%s version %s", filepath.Base(os.Args[0]), version)
+
+	if commit != "" {
+		result = fmt.Sprintf("%s\ncommit: %s", result, commit)
+	}
+	if date != "" {
+		result = fmt.Sprintf("%s\nbuilt at: %s", result, date)
+	}
+	if info, ok := debug.ReadBuildInfo(); ok && info.Main.Sum != "" {
+		result = fmt.Sprintf("%s\nmodule version: %s, checksum: %s", result, info.Main.Version, info.Main.Sum)
+	}
+	result = fmt.Sprintf("%s\ngoos: %s\ngoarch: %s", result, runtime.GOOS, runtime.GOARCH)
+
+	return result
+}

errchkjson.go

@@ -32,6 +32,7 @@ func NewAnalyzer() *analysis.Analyzer {
 	a.Flags.Init("errchkjson", flag.ExitOnError)
 	a.Flags.BoolVar(&errchkjson.omitSafe, "omit-safe", false, "if omit-safe is true, checking of safe returns is omitted")
 	a.Flags.BoolVar(&errchkjson.reportNoExported, "report-no-exported", false, "if report-no-exported is true, encoding a struct without exported fields is reported as issue")
+	a.Flags.Var(versionFlag{}, "V", "print version and exit")
 
 	return a
 }
@@ -154,7 +155,7 @@ func (e *errchkjson) jsonSafe(t types.Type, level int, seenTypes map[types.Type]
 		return nil
 	}
 
-	if types.Implements(t, textMarshalerInterface()) {
+	if types.Implements(t, textMarshalerInterface()) || types.Implements(t, jsonMarshalerInterface()) {
 		return fmt.Errorf("unsafe type `%s` found", t.String())
 	}
 
@@ -247,7 +248,7 @@ func (e *errchkjson) jsonSafe(t types.Type, level int, seenTypes map[types.Type]
 }
 
 func jsonSafeMapKey(t types.Type) error {
-	if types.Implements(t, textMarshalerInterface()) {
+	if types.Implements(t, textMarshalerInterface()) || types.Implements(t, jsonMarshalerInterface()) {
 		return fmt.Errorf("unsafe type `%s` as map key found", t.String())
 	}
 	switch ut := t.Underlying().(type) {
@@ -268,7 +269,7 @@ func jsonSafeMapKey(t types.Type) error {
 	}
 }
 
-// Construct *types.Interface for interface TextMarshaler
+// Construct *types.Interface for interface encoding.TextMarshaler
 //     type TextMarshaler interface {
 //         MarshalText() (text []byte, err error)
 //     }
@@ -287,3 +288,23 @@ func textMarshalerInterface() *types.Interface {
 
 	return textMarshalerInterface
 }
+
+// Construct *types.Interface for interface json.Marshaler
+//     type Marshaler interface {
+//         MarshalJSON() ([]byte, error)
+//     }
+//
+func jsonMarshalerInterface() *types.Interface {
+	textMarshalerInterface := types.NewInterfaceType([]*types.Func{
+		types.NewFunc(token.NoPos, nil, "MarshalJSON", types.NewSignature(
+			nil, nil, types.NewTuple(
+				types.NewVar(token.NoPos, nil, "",
+					types.NewSlice(
+						types.Universe.Lookup("byte").Type())),
+				types.NewVar(token.NoPos, nil, "", types.Universe.Lookup("error").Type())),
+			false)),
+	}, nil)
+	textMarshalerInterface.Complete()
+
+	return textMarshalerInterface
+}

testdata/src/nosafe/a.go

@@ -10,12 +10,20 @@ import (
 
 type marshalText struct{}
 
-func (mt marshalText) MarshalText() ([]byte, error) {
+func (_ marshalText) MarshalText() ([]byte, error) {
 	return []byte(`mt`), nil
 }
 
 var _ encoding.TextMarshaler = marshalText(struct{}{})
 
+type marshalJSON struct{}
+
+func (_ marshalJSON) MarshalJSON() ([]byte, error) {
+	return []byte(`mj`), nil
+}
+
+var _ json.Marshaler = marshalJSON(struct{}{})
+
 // JSONMarshalSafeTypesWithNoSafe contains a multitude of test cases to marshal different combinations of types to JSON,
 // that are safe, that is, they will never return an error, if these types are marshaled to JSON.
 func JSONMarshalSafeTypesWithNoSafe() {
@@ -266,6 +274,8 @@ type (
 		Stringer             fmt.Stringer
 		Mt                   marshalText
 		MapMarshalTextString map[marshalText]string
+		Mj                   marshalJSON
+		MapMarshalJSONString map[marshalJSON]string
 
 		C128         complex128
 		C128Ptr      *complex128
@@ -301,6 +311,8 @@ func JSONMarshalSafeStructWithUnexportedFieldsWithNoSafe() {
 		stringer             fmt.Stringer                    // unsafe unexported
 		mt                   marshalText                     // unsafe unexported
 		mapMarshalTextString map[marshalText]string          // unsafe unexported
+		mj                   marshalJSON                     // unsafe unexported
+		mapMarshalJSONString map[marshalJSON]string          // unsafe unexported
 		unexportedStruct     ExportedUnsafeAndInvalidStruct  // unsafe unexported
 		unexportedStructPtr  *ExportedUnsafeAndInvalidStruct // unsafe unexported
 
@@ -366,6 +378,8 @@ func JSONMarshalSafeStructWithOmittedFieldsWithNoSafe() {
 		Stringer             fmt.Stringer                    `json:"-"` // unsafe exported but omitted
 		Mt                   marshalText                     `json:"-"` // unsafe exported but omitted
 		MapMarshalTextString map[marshalText]string          `json:"-"` // unsafe exported but omitted
+		Mj                   marshalJSON                     `json:"-"` // unsafe exported but omitted
+		MapMarshalJSONString map[marshalJSON]string          `json:"-"` // unsafe exported but omitted
 		ExportedStruct       ExportedUnsafeAndInvalidStruct  `json:"-"` // unsafe exported but omitted
 		ExportedStructPtr    *ExportedUnsafeAndInvalidStruct `json:"-"` // unsafe exported but omitted
 
@@ -506,6 +520,16 @@ func JSONMarshalUnsafeTypes() {
 	_, _ = json.Marshal(mapMarshalTextString)   // want "Error return value of `encoding/json.Marshal` is not checked: unsafe type `nosafe.marshalText` as map key found"
 	_, err = json.Marshal(mapMarshalTextString) // err is checked
 	_ = err
+
+	var mj marshalJSON
+	_, _ = json.Marshal(mj)   // want "Error return value of `encoding/json.Marshal` is not checked: unsafe type `nosafe.marshalJSON` found"
+	_, err = json.Marshal(mj) // err is checked
+	_ = err
+
+	var mapMarshalJSONString map[marshalJSON]string
+	_, _ = json.Marshal(mapMarshalJSONString)   // want "Error return value of `encoding/json.Marshal` is not checked: unsafe type `nosafe.marshalJSON` as map key found"
+	_, err = json.Marshal(mapMarshalJSONString) // err is checked
+	_ = err
 }
 
 // JSONMarshalInvalidTypes contains a multitude of test cases to marshal different combinations of types to JSON,

testdata/src/standard/a.go

@@ -10,12 +10,20 @@ import (
 
 type marshalText struct{}
 
-func (mt marshalText) MarshalText() ([]byte, error) {
+func (_ marshalText) MarshalText() ([]byte, error) {
 	return []byte(`mt`), nil
 }
 
 var _ encoding.TextMarshaler = marshalText(struct{}{})
 
+type marshalJSON struct{}
+
+func (_ marshalJSON) MarshalJSON() ([]byte, error) {
+	return []byte(`mj`), nil
+}
+
+var _ json.Marshaler = marshalJSON(struct{}{})
+
 // JSONMarshalSafeTypes contains a multitude of test cases to marshal different combinations of types to JSON,
 // that are safe, that is, they will never return an error, if these types are marshaled to JSON.
 func JSONMarshalSafeTypes() {
@@ -266,6 +274,8 @@ type (
 		Stringer             fmt.Stringer
 		Mt                   marshalText
 		MapMarshalTextString map[marshalText]string
+		Mj                   marshalJSON
+		MapMarshalJSONString map[marshalJSON]string
 
 		C128         complex128
 		C128Ptr      *complex128
@@ -301,6 +311,8 @@ func JSONMarshalSafeStructWithUnexportedFields() {
 		stringer             fmt.Stringer                    // unsafe unexported
 		mt                   marshalText                     // unsafe unexported
 		mapMarshalTextString map[marshalText]string          // unsafe unexported
+		mj                   marshalJSON                     // unsafe unexported
+		mapMarshalJSONString map[marshalJSON]string          // unsafe unexported
 		unexportedStruct     ExportedUnsafeAndInvalidStruct  // unsafe unexported
 		unexportedStructPtr  *ExportedUnsafeAndInvalidStruct // unsafe unexported
 
@@ -366,6 +378,8 @@ func JSONMarshalSafeStructWithOmittedFields() {
 		Stringer             fmt.Stringer                    `json:"-"` // unsafe exported but omitted
 		Mt                   marshalText                     `json:"-"` // unsafe exported but omitted
 		MapMarshalTextString map[marshalText]string          `json:"-"` // unsafe exported but omitted
+		Mj                   marshalJSON                     `json:"-"` // unsafe exported but omitted
+		MapMarshalJSONString map[marshalJSON]string          `json:"-"` // unsafe exported but omitted
 		ExportedStruct       ExportedUnsafeAndInvalidStruct  `json:"-"` // unsafe exported but omitted
 		ExportedStructPtr    *ExportedUnsafeAndInvalidStruct `json:"-"` // unsafe exported but omitted
 
@@ -506,6 +520,16 @@ func JSONMarshalUnsafeTypes() {
 	_, _ = json.Marshal(mapMarshalTextString)   // want "Error return value of `encoding/json.Marshal` is not checked: unsafe type `standard.marshalText` as map key found"
 	_, err = json.Marshal(mapMarshalTextString) // err is checked
 	_ = err
+
+	var mj marshalJSON
+	_, _ = json.Marshal(mj)   // want "Error return value of `encoding/json.Marshal` is not checked: unsafe type `standard.marshalJSON` found"
+	_, err = json.Marshal(mj) // err is checked
+	_ = err
+
+	var mapMarshalJSONString map[marshalJSON]string
+	_, _ = json.Marshal(mapMarshalJSONString)   // want "Error return value of `encoding/json.Marshal` is not checked: unsafe type `standard.marshalJSON` as map key found"
+	_, err = json.Marshal(mapMarshalJSONString) // err is checked
+	_ = err
 }
 
 // JSONMarshalInvalidTypes contains a multitude of test cases to marshal different combinations of types to JSON,

version.go

@@ -0,0 +1,19 @@
+package errchkjson
+
+import (
+	"fmt"
+	"os"
+)
+
+var Version = "errchkjson version dev"
+
+type versionFlag struct{}
+
+func (versionFlag) IsBoolFlag() bool { return true }
+func (versionFlag) Get() interface{} { return nil }
+func (versionFlag) String() string   { return "" }
+func (versionFlag) Set(s string) error {
+	fmt.Println(Version)
+	os.Exit(0)
+	return nil
+}