checkers/internal/astwalk: adapted from a lintpack (#934)

Since we might want to reduce dependencies from
a lintpack project that is going to be replaced
with go/analysis, it's beneficial to move useful
things we want to keep inside go-critic repository.

astwalk only depends on the lintpack.FileWalker
interface that can be easily moved or replaced later.

Refs #854

Signed-off-by: Iskander Sharipov <quasilyte@gmail.com>

checkers/appendAssign_checker.go

@@ -6,7 +6,7 @@ import (
 	"go/types"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astequal"
 	"github.com/go-toolsmith/astp"
 	"golang.org/x/tools/go/ast/astutil"

checkers/appendCombine_checker.go

@@ -5,7 +5,7 @@ import (
 	"go/token"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astcast"
 	"github.com/go-toolsmith/astequal"
 )

checkers/argOrder_checker.go

@@ -5,7 +5,7 @@ import (
 	"go/types"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astcast"
 	"github.com/go-toolsmith/astcopy"
 	"github.com/go-toolsmith/astp"

checkers/assignOp_checker.go

@@ -5,7 +5,7 @@ import (
 	"go/token"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astcopy"
 	"github.com/go-toolsmith/astequal"
 	"github.com/go-toolsmith/typep"

checkers/badCall_checker.go

@@ -4,7 +4,7 @@ import (
 	"go/ast"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astcast"
 	"github.com/go-toolsmith/astcopy"
 )

checkers/badCond_checker.go

@@ -7,7 +7,7 @@ import (
 
 	"github.com/go-critic/go-critic/checkers/internal/lintutil"
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astcast"
 	"github.com/go-toolsmith/astcopy"
 	"github.com/go-toolsmith/astequal"

checkers/badRegexp_checker.go

@@ -9,7 +9,7 @@ import (
 	"unicode/utf8"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/quasilyte/regex/syntax"
 )
 

checkers/boolExprSimplify_checker.go

@@ -8,7 +8,7 @@ import (
 
 	"github.com/go-critic/go-critic/checkers/internal/lintutil"
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astcast"
 	"github.com/go-toolsmith/astcopy"
 	"github.com/go-toolsmith/astequal"

checkers/builtinShadow_checker.go

@@ -4,7 +4,7 @@ import (
 	"go/ast"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 )
 
 func init() {

checkers/captLocal_checker.go

@@ -4,7 +4,7 @@ import (
 	"go/ast"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 )
 
 func init() {

checkers/caseOrder_checker.go

@@ -5,7 +5,7 @@ import (
 	"go/types"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 )
 
 func init() {

checkers/codegenComment_checker.go

@@ -6,7 +6,7 @@ import (
 	"strings"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 )
 
 func init() {

checkers/commentFormatting_checker.go

@@ -8,7 +8,7 @@ import (
 	"unicode/utf8"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 )
 
 func init() {

checkers/commentedOutCode_checker.go

@@ -8,7 +8,7 @@ import (
 	"strings"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/strparse"
 )
 

checkers/commentedOutImport_checker.go

@@ -6,7 +6,7 @@ import (
 	"regexp"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 )
 
 func init() {

checkers/defaultCaseOrder_checker.go

@@ -4,7 +4,7 @@ import (
 	"go/ast"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 )
 
 func init() {

checkers/deferUnlambda_checker.go

@@ -5,7 +5,7 @@ import (
 	"go/types"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astcast"
 )
 

checkers/deprecatedComment_checker.go

@@ -6,7 +6,7 @@ import (
 	"strings"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 )
 
 func init() {

checkers/docStub_checker.go

@@ -7,7 +7,7 @@ import (
 	"strings"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 )
 
 func init() {

checkers/dupArg_checker.go

@@ -5,7 +5,7 @@ import (
 	"go/types"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astcast"
 	"github.com/go-toolsmith/astequal"
 )

checkers/dupBranchBody_checker.go

@@ -4,7 +4,7 @@ import (
 	"go/ast"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astequal"
 )
 

checkers/dupCase_checker.go

@@ -5,7 +5,7 @@ import (
 
 	"github.com/go-critic/go-critic/checkers/internal/lintutil"
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 )
 
 func init() {

checkers/dupSubExpr_checker.go

@@ -6,7 +6,7 @@ import (
 	"go/types"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astequal"
 	"github.com/go-toolsmith/typep"
 )

checkers/elseif_checker.go

@@ -4,7 +4,7 @@ import (
 	"go/ast"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astp"
 )
 

checkers/emptyFallthrough_checker.go

@@ -5,7 +5,7 @@ import (
 	"go/token"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 )
 
 func init() {

checkers/emptyStringTest_checker.go

@@ -5,7 +5,7 @@ import (
 	"go/token"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astcast"
 	"github.com/go-toolsmith/astcopy"
 	"github.com/go-toolsmith/typep"

checkers/equalFold_checker.go

@@ -5,7 +5,7 @@ import (
 	"go/token"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astcast"
 	"github.com/go-toolsmith/astequal"
 )

checkers/evalOrder_checker.go

@@ -7,7 +7,7 @@ import (
 
 	"github.com/go-critic/go-critic/checkers/internal/lintutil"
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astcast"
 	"github.com/go-toolsmith/astequal"
 	"github.com/go-toolsmith/typep"

checkers/exitAfterDefer_checker.go

@@ -4,7 +4,7 @@ import (
 	"go/ast"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astfmt"
 	"github.com/go-toolsmith/astp"
 	"golang.org/x/tools/go/ast/astutil"

checkers/filepathJoin_checker.go

@@ -5,7 +5,7 @@ import (
 	"strings"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astcast"
 )
 

checkers/flagDeref_checker.go

@@ -4,7 +4,7 @@ import (
 	"go/ast"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 )
 
 func init() {

checkers/flagName_checker.go

@@ -7,7 +7,7 @@ import (
 	"strings"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astcast"
 )
 

checkers/hexLiteral_checker.go

@@ -6,7 +6,7 @@ import (
 	"strings"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astcast"
 )
 

checkers/hugeParam_checker.go

@@ -4,7 +4,7 @@ import (
 	"go/ast"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 )
 
 func init() {

checkers/ifElseChain_checker.go

@@ -4,7 +4,7 @@ import (
 	"go/ast"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 )
 
 func init() {

checkers/importShadow_checker.go

@@ -5,7 +5,7 @@ import (
 	"go/types"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 )
 
 func init() {

checkers/indexAlloc_checker.go

@@ -4,7 +4,7 @@ import (
 	"go/ast"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astcast"
 	"github.com/go-toolsmith/typep"
 )

checkers/initClause_checker.go

@@ -4,7 +4,7 @@ import (
 	"go/ast"
 
 	"github.com/go-lintpack/lintpack"
-	"github.com/go-lintpack/lintpack/astwalk"
+	"github.com/go-critic/go-critic/checkers/internal/astwalk"
 	"github.com/go-toolsmith/astp"
 )
 

checkers/internal/astwalk/comment_walker.go

@@ -0,0 +1,41 @@
+package astwalk
+
+import (
+	"go/ast"
+	"strings"
+)
+
+type commentWalker struct {
+	visitor CommentVisitor
+}
+
+func (w *commentWalker) WalkFile(f *ast.File) {
+	if !w.visitor.EnterFile(f) {
+		return
+	}
+
+	for _, cg := range f.Comments {
+		visitCommentGroups(cg, w.visitor.VisitComment)
+	}
+}
+
+func visitCommentGroups(cg *ast.CommentGroup, visit func(*ast.CommentGroup)) {
+	var group []*ast.Comment
+	visitGroup := func(list []*ast.Comment) {
+		if len(list) == 0 {
+			return
+		}
+		cg := &ast.CommentGroup{List: list}
+		visit(cg)
+	}
+	for _, comment := range cg.List {
+		if strings.HasPrefix(comment.Text, "/*") {
+			visitGroup(group)
+			group = group[:0]
+			visitGroup([]*ast.Comment{comment})
+		} else {
+			group = append(group, comment)
+		}
+	}
+	visitGroup(group)
+}