Initial example

Author: dbraley

README.md

@@ -0,0 +1,34 @@
+package linters
+
+import (
+	"go/ast"
+	"golang.org/x/tools/go/analysis"
+	"strings"
+)
+
+var TodoAnalyzer = &analysis.Analyzer{
+	Name: "todo",
+	Doc:  "finds todos without author",
+	Run:  run,
+}
+
+func run(pass *analysis.Pass) (interface{}, error) {
+	for _, file := range pass.Files {
+		ast.Inspect(file, func(n ast.Node) bool {
+			if comment, ok := n.(*ast.Comment); ok {
+				if strings.HasPrefix(comment.Text, "// TODO:") ||
+					strings.HasPrefix(comment.Text, "// TODO():") {
+					pass.Report(analysis.Diagnostic{
+						Pos:            comment.Pos(),
+						End:            0,
+						Category:       "todo",
+						Message:        "TODO comment has no author",
+						SuggestedFixes: nil,
+					})
+				}
+			}
+			return true
+		})
+	}
+	return nil, nil
+}

example.go

@@ -0,0 +1,12 @@
+module github.com/dbraley/example-linter
+
+// All versions here need to be the same as in golangci-lint/mod.go if present
+
+go 1.12
+
+require (
+	github.com/stretchr/testify v1.4.0
+	golang.org/x/tools v0.0.0-20191010075000-0337d82405ff
+)
+
+replace golang.org/x/tools => github.com/golangci/tools v0.0.0-20190915081525-6aa350649b1c

go.mod

@@ -0,0 +1,20 @@
+github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/golangci/tools v0.0.0-20190915081525-6aa350649b1c h1:JF7g2hV+1F/DwJ3CrSxOc9ZNVY6N8zYt5mB0Qve//fU=
+github.com/golangci/tools v0.0.0-20190915081525-6aa350649b1c/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
+github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/tools v0.0.0-20191031220737-6d8f1af9ccc0 h1:+o3suEKE/4hCUt6qjV8SDcVZhz2dO8UWlHliCa+4bvg=
+golang.org/x/tools v0.0.0-20191031220737-6d8f1af9ccc0/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
+gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

go.sum

@@ -0,0 +1,34 @@
+package linters
+
+// Tests for linters.
+
+import (
+	"github.com/stretchr/testify/suite"
+	"path/filepath"
+	"runtime"
+	"testing"
+
+	"golang.org/x/tools/go/analysis/analysistest"
+)
+
+type linterSuite struct {
+	suite.Suite
+}
+
+func (suite *linterSuite) TestContextLinter() {
+	analysistest.Run(
+		suite.T(), TestdataDir(),
+		TodoAnalyzer, "testlintdata/todo")
+}
+
+func TestLinterSuite(t *testing.T) {
+	suite.Run(t, new(linterSuite))
+}
+
+func TestdataDir() string {
+	_, testFilename, _, ok := runtime.Caller(1)
+	if !ok {
+		panic("unable to get current test filename")
+	}
+	return filepath.Join(filepath.Dir(testFilename), "testdata")
+}

lint_test.go

@@ -0,0 +1,37 @@
+// This must be package main
+package main
+
+import (
+	"fmt"
+	linters "github.com/dbraley/example-linter"
+	"golang.org/x/tools/go/analysis"
+)
+
+type analyzerPlugin struct{}
+
+func main() {
+	fmt.Printf("Plugin library for %s", AnalyzerPlugin.GetLinterName())
+	fmt.Println("To compile this into a plugin, run:")
+	fmt.Println("	 go build -buildmode=plugin -o /desired/path/to/example.so plugin/example.go")
+	fmt.Println("See README.md for more info")
+}
+
+// This must be implemented
+func (*analyzerPlugin) GetLinterName() string {
+	return "example"
+}
+
+// This must be implemented
+func (*analyzerPlugin) GetLinterDesc() string {
+	return "A package of custom linters that can be used in golangci-lint"
+}
+
+// This must be implemented
+func (*analyzerPlugin) GetAnalyzers() []*analysis.Analyzer {
+	return []*analysis.Analyzer{
+		linters.TodoAnalyzer,
+	}
+}
+
+// This must be defined
+var AnalyzerPlugin analyzerPlugin

plugin/example.go

@@ -0,0 +1,21 @@
+package todo
+
+// comment without a to do
+func SomeFunc1() {
+	_ = 1 + 1
+}
+
+// TODO: do something	// want "TODO comment has no author"
+func SomeFunc2() {
+	_ = 1 + 2
+}
+
+// TODO(): do something // want "TODO comment has no author"
+func SomeFunc3() {
+	_ = 1 + 3
+}
+
+// TODO(dbraley): Do something with the value
+func SomeFunc4() {
+	_ = 1 + 4
+}