Add analysis.Analyzer interface (#14)

Also update linters

.circleci/config.yml

@@ -3,10 +3,10 @@ version: 2
 jobs:
   build:
     docker:
-      - image: circleci/golang:1.12
+      - image: cimg/go:1.17.7
     steps:
       - checkout
-      - run: sudo apt-get -y -qq install python python-pip
+      - run: sudo apt-get update && sudo apt-get -y -qq install python pip
       - run: pip install pre-commit
       - run: SKIP=no-commit-to-branch pre-commit run -a
       - run: go test ./...

.golangci.yml

@@ -1,2 +1,3 @@
 linters:
-  enable-all: true
+  enable:
+    - prealloc

.pre-commit-config.yaml

@@ -1,5 +1,5 @@
 repos:
   - repo: https://github.com/golangci/golangci-lint
-    rev: v1.17.1
+    rev: v1.44.2
     hooks:
       - id: golangci-lint

forbidigo/forbidigo.go

@@ -16,13 +16,15 @@ import (
 
 type Issue interface {
 	Details() string
+	Pos() token.Pos
 	Position() token.Position
 	String() string
 }
 
 type UsedIssue struct {
 	identifier string
 	pattern    string
+	pos        token.Pos
 	position   token.Position
 	customMsg  string
 }
@@ -39,6 +41,10 @@ func (a UsedIssue) Position() token.Position {
 	return a.position
 }
 
+func (a UsedIssue) Pos() token.Pos {
+	return a.pos
+}
+
 func (a UsedIssue) String() string { return toString(a) }
 
 func toString(i UsedIssue) string {
@@ -96,7 +102,7 @@ type visitor struct {
 }
 
 func (l *Linter) Run(fset *token.FileSet, nodes ...ast.Node) ([]Issue, error) {
-	var issues []Issue //nolint:prealloc // we don't know how many there will be
+	var issues []Issue 
 	for _, node := range nodes {
 		var comments []*ast.CommentGroup
 		isTestFile := false
@@ -167,6 +173,7 @@ func (v *visitor) Visit(node ast.Node) ast.Visitor {
 			v.issues = append(v.issues, UsedIssue{
 				identifier: v.textFor(node),
 				pattern:    p.pattern.String(),
+				pos:        node.Pos(),
 				position:   v.fset.Position(node.Pos()),
 				customMsg:  p.msg,
 			})
@@ -188,7 +195,7 @@ func (v *visitor) permit(node ast.Node) bool {
 		return false
 	}
 	nodePos := v.fset.Position(node.Pos())
-	var nolint = regexp.MustCompile(fmt.Sprintf(`^//\s?permit:%s\b`, regexp.QuoteMeta(v.textFor(node))))
+	nolint := regexp.MustCompile(fmt.Sprintf(`^//\s?permit:%s\b`, regexp.QuoteMeta(v.textFor(node))))
 	for _, c := range v.comments {
 		commentPos := v.fset.Position(c.Pos())
 		if commentPos.Line == nodePos.Line && len(c.List) > 0 && nolint.MatchString(c.List[0].Text) {

main.go

@@ -43,7 +43,7 @@ func main() {
 		log.Fatalf("Could not create linter: %s", err)
 	}
 
-	var issues []forbidigo.Issue //nolint:prealloc // we don't know how many there will be
+	var issues []forbidigo.Issue 
 	for _, p := range pkgs {
 		nodes := make([]ast.Node, 0, len(p.Syntax))
 		for _, n := range p.Syntax {

pkg/analyzer/analyzer.go

@@ -0,0 +1,87 @@
+package analyzer
+
+import (
+	"flag"
+	"go/ast"
+
+	"github.com/ashanbrown/forbidigo/forbidigo"
+	"github.com/pkg/errors"
+	"golang.org/x/tools/go/analysis"
+)
+
+type listVar struct {
+	values *[]string
+}
+
+func (v *listVar) Set(value string) error {
+	*v.values = append(*v.values, value)
+	if value == "" {
+		return errors.New("value cannot be empty")
+	}
+	return nil
+}
+
+func (v *listVar) String() string {
+	return ""
+}
+
+type analyzer struct {
+	patterns           []string
+	usePermitDirective bool
+	includeExamples    bool
+}
+
+// NewAnalyzer returns a go/analysis-compatible analyzer
+// The "-p" argument can be used to add a pattern.
+// Set "-examples" to analyze godoc examples
+// Set "-permit=false" to ignore "//permit:<identifier>" directives.
+func NewAnalyzer() *analysis.Analyzer {
+	var flags flag.FlagSet
+	a := analyzer{
+		usePermitDirective: true,
+		includeExamples:    true,
+	}
+	flags.Var(&listVar{values: &a.patterns}, "p", "pattern")
+	flags.BoolVar(&a.includeExamples, "examples", false, "check godoc examples")
+	flags.BoolVar(&a.usePermitDirective, "permit", true, `when set, lines with "//permit" directives will be ignored`)
+	return &analysis.Analyzer{
+		Name:  "forbidigo",
+		Doc:   "forbid identifiers",
+		Run:   a.runAnalysis,
+		Flags: flags,
+	}
+}
+
+func (a *analyzer) runAnalysis(pass *analysis.Pass) (interface{}, error) {
+	if a.patterns == nil {
+		a.patterns = forbidigo.DefaultPatterns()
+	}
+	linter, err := forbidigo.NewLinter(a.patterns,
+		forbidigo.OptionIgnorePermitDirectives(!a.usePermitDirective),
+		forbidigo.OptionExcludeGodocExamples(!a.includeExamples),
+	)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to configure linter")
+	}
+	nodes := make([]ast.Node, 0, len(pass.Files))
+	for _, f := range pass.Files {
+		nodes = append(nodes, f)
+	}
+	issues, err := linter.Run(pass.Fset, nodes...)
+	if err != nil {
+		return nil, err
+	}
+	reportIssues(pass, issues)
+	return nil, nil
+}
+
+func reportIssues(pass *analysis.Pass, issues []forbidigo.Issue) {
+	for _, i := range issues {
+		diag := analysis.Diagnostic{
+			Pos:      i.Pos(),
+			Message:  i.Details(),
+			Category: "restriction",
+		}
+		pass.Report(diag)
+	}
+}

pkg/analyzer/analyzer_test.go

@@ -0,0 +1,14 @@
+package analyzer_test
+
+import (
+	"testing"
+
+	"github.com/ashanbrown/forbidigo/pkg/analyzer"
+	"golang.org/x/tools/go/analysis/analysistest"
+)
+
+func TestAnalyzer(t *testing.T) {
+	testdata := analysistest.TestData()
+	a := analyzer.NewAnalyzer()
+	analysistest.Run(t, testdata, a, "")
+}

pkg/analyzer/testdata/forbidden.go

@@ -0,0 +1,10 @@
+package testdata
+
+import "fmt"
+
+func Foo() {
+	fmt.Println("here I am") // want "forbidden by pattern"
+	fmt.Printf("this is ok") //permit:fmt.Printf // this is ok
+	print("not ok")          // want "forbidden by pattern"
+	println("also not ok")   // want "forbidden by pattern"
+}