Simplify internal comment representation.

checks.go

@@ -30,21 +30,16 @@ var (
 
 // checkComments checks every comment accordings to the rules from
 // `settings` argument.
-func checkComments(fset *token.FileSet, comments []comment, settings Settings) []Issue {
+func checkComments(comments []comment, settings Settings) []Issue {
 	var issues []Issue // nolint: prealloc
 	for _, c := range comments {
-		if c.ast == nil || len(c.ast.List) == 0 {
-			continue
-		}
-
 		if settings.Period {
-			if iss := checkCommentForPeriod(fset, c); iss != nil {
+			if iss := checkCommentForPeriod(c); iss != nil {
 				issues = append(issues, *iss)
 			}
 		}
-
 		if settings.Capital {
-			if iss := checkCommentForCapital(fset, c); len(iss) > 0 {
+			if iss := checkCommentForCapital(c); len(iss) > 0 {
 				issues = append(issues, iss...)
 			}
 		}
@@ -54,29 +49,24 @@ func checkComments(fset *token.FileSet, comments []comment, settings Settings) [
 
 // checkCommentForPeriod checks that the last sentense of the comment ends
 // in a period.
-func checkCommentForPeriod(fset *token.FileSet, c comment) *Issue {
-	// Save global line number and indentation
-	start := fset.Position(c.ast.List[0].Slash)
-
-	text := getText(c.ast)
-
-	pos, ok := checkPeriod(text)
+func checkCommentForPeriod(c comment) *Issue {
+	pos, ok := checkPeriod(c.text)
 	if ok {
 		return nil
 	}
 
 	// Shift position by the length of comment's special symbols: /* or //
-	isBlock := strings.HasPrefix(c.ast.List[0].Text, "/*")
+	isBlock := strings.HasPrefix(c.lines[0], "/*")
 	if (isBlock && pos.line == 1) || !isBlock {
 		pos.column += 2
 	}
 
 	iss := Issue{
 		Pos: token.Position{
-			Filename: start.Filename,
-			Offset:   start.Offset,
-			Line:     pos.line + start.Line - 1,
-			Column:   pos.column + start.Column - 1,
+			Filename: c.start.Filename,
+			Offset:   c.start.Offset,
+			Line:     pos.line + c.start.Line - 1,
+			Column:   pos.column + c.start.Column - 1,
 		},
 		Message: noPeriodMessage,
 	}
@@ -98,31 +88,26 @@ func checkCommentForPeriod(fset *token.FileSet, c comment) *Issue {
 // checkCommentForCapital checks that the each sentense of the comment starts with
 // a capital letter.
 // nolint: unparam
-func checkCommentForCapital(fset *token.FileSet, c comment) []Issue {
-	// Save global line number and indent
-	start := fset.Position(c.ast.List[0].Slash)
-
-	text := getText(c.ast)
-
-	pp := checkCapital(text, c.decl)
+func checkCommentForCapital(c comment) []Issue {
+	pp := checkCapital(c.text, c.decl)
 	if len(pp) == 0 {
 		return nil
 	}
 
 	issues := make([]Issue, len(pp))
 	for i, pos := range pp {
 		// Shift position by the length of comment's special symbols: /* or //
-		isBlock := strings.HasPrefix(c.ast.List[0].Text, "/*")
+		isBlock := strings.HasPrefix(c.lines[0], "/*")
 		if (isBlock && pos.line == 1) || !isBlock {
 			pos.column += 2
 		}
 
 		iss := Issue{
 			Pos: token.Position{
-				Filename: start.Filename,
-				Offset:   start.Offset,
-				Line:     pos.line + start.Line - 1,
-				Column:   pos.column + start.Column - 1,
+				Filename: c.start.Filename,
+				Offset:   c.start.Offset,
+				Line:     pos.line + c.start.Line - 1,
+				Column:   pos.column + c.start.Column - 1,
 			},
 			Message: noCapitalMessage,
 		}

checks_test.go

@@ -1,22 +1,6 @@
 package godot
 
-import (
-	"go/ast"
-	"testing"
-)
-
-func TestCheckComments(t *testing.T) {
-	// Check only case with empty input, other cases are checked in TestRun
-
-	comments := []comment{
-		{ast: nil},
-		{ast: &ast.CommentGroup{List: nil}},
-	}
-	issues := checkComments(nil, comments, Settings{})
-	if len(issues) > 0 {
-		t.Fatalf("Unexpected issues: %d", len(issues))
-	}
-}
+import "testing"
 
 func TestCheckPeriod(t *testing.T) {
 	testCases := []struct {

getters.go

@@ -73,6 +73,9 @@ func getBlockComments(file *ast.File, fset *token.FileSet, lines []string) []com
 			continue
 		}
 		for _, c := range file.Comments {
+			if c == nil || len(c.List) == 0 {
+				continue
+			}
 			// Skip comments outside this block
 			if d.Lparen > c.Pos() || c.Pos() > d.Rparen {
 				continue
@@ -87,8 +90,9 @@ func getBlockComments(file *ast.File, fset *token.FileSet, lines []string) []com
 			firstLine := fset.Position(c.Pos()).Line
 			lastLine := fset.Position(c.End()).Line
 			comments = append(comments, comment{
-				ast:   c,
 				lines: lines[firstLine-1 : lastLine],
+				text:  getText(c),
+				start: fset.Position(c.List[0].Slash),
 			})
 		}
 	}
@@ -99,14 +103,18 @@ func getBlockComments(file *ast.File, fset *token.FileSet, lines []string) []com
 func getTopLevelComments(file *ast.File, fset *token.FileSet, lines []string) []comment {
 	var comments []comment // nolint: prealloc
 	for _, c := range file.Comments {
+		if c == nil || len(c.List) == 0 {
+			continue
+		}
 		if fset.Position(c.Pos()).Column != 1 {
 			continue
 		}
 		firstLine := fset.Position(c.Pos()).Line
 		lastLine := fset.Position(c.End()).Line
 		comments = append(comments, comment{
-			ast:   c,
 			lines: lines[firstLine-1 : lastLine],
+			text:  getText(c),
+			start: fset.Position(c.List[0].Slash),
 		})
 	}
 	return comments
@@ -124,15 +132,16 @@ func getDeclarationComments(file *ast.File, fset *token.FileSet, lines []string)
 			cg = d.Doc
 		}
 
-		if cg == nil {
+		if cg == nil || len(cg.List) == 0 {
 			continue
 		}
 
 		firstLine := fset.Position(cg.Pos()).Line
 		lastLine := fset.Position(cg.End()).Line
 		comments = append(comments, comment{
-			ast:   cg,
 			lines: lines[firstLine-1 : lastLine],
+			text:  getText(cg),
+			start: fset.Position(cg.List[0].Slash),
 		})
 	}
 	return comments
@@ -142,11 +151,15 @@ func getDeclarationComments(file *ast.File, fset *token.FileSet, lines []string)
 func getAllComments(file *ast.File, fset *token.FileSet, lines []string) []comment {
 	var comments []comment //nolint: prealloc
 	for _, c := range file.Comments {
+		if c == nil || len(c.List) == 0 {
+			continue
+		}
 		firstLine := fset.Position(c.Pos()).Line
 		lastLine := fset.Position(c.End()).Line
 		comments = append(comments, comment{
-			ast:   c,
 			lines: lines[firstLine-1 : lastLine],
+			start: fset.Position(c.List[0].Slash),
+			text:  getText(c),
 		})
 	}
 	return comments
@@ -203,7 +216,7 @@ func readFile(file *ast.File, fset *token.FileSet) ([]string, error) {
 func setDecl(comments, decl []comment) {
 	for _, d := range decl {
 		for i, c := range comments {
-			if d.ast.Pos() == c.ast.Pos() {
+			if d.start == c.start {
 				comments[i].decl = true
 				break
 			}

getters_test.go

@@ -48,12 +48,11 @@ func TestGetComments(t *testing.T) {
 			}
 			var expected int
 			for _, c := range comments {
-				if strings.Contains(c.ast.Text(), "[NONE]") {
+				if linesContain(c.lines, "[NONE]") {
 					continue
 				}
-				text := c.ast.Text()
 				for _, s := range tt.contains {
-					if strings.Contains(text, s) {
+					if strings.Contains(c.text, s) {
 						expected++
 						break
 					}
@@ -192,3 +191,12 @@ func TestGetText(t *testing.T) {
 		})
 	}
 }
+
+func linesContain(lines []string, s string) bool {
+	for _, ln := range lines {
+		if strings.Contains(ln, s) {
+			return true
+		}
+	}
+	return false
+}

godot.go

@@ -30,13 +30,14 @@ type position struct {
 	column int
 }
 
-// comment is an internal representation of AST comment entity with rendered
-// lines attached. The latter is used for creating a full replacement for
+// comment is an internal representation of AST comment entity with additional
+// data attached. The latter is used for creating a full replacement for
 // the line with issues.
 type comment struct {
-	ast   *ast.CommentGroup
-	lines []string
-	decl  bool
+	lines []string       // unmodified lines from file
+	text  string         // concatenated `lines` with special parts excluded
+	start token.Position // position of the first symbol in comment
+	decl  bool           // whether comment is a special one (should not be checked)
 }
 
 // Run runs this linter on the provided code.
@@ -46,7 +47,7 @@ func Run(file *ast.File, fset *token.FileSet, settings Settings) ([]Issue, error
 		return nil, fmt.Errorf("get comments: %v", err)
 	}
 
-	issues := checkComments(fset, comments, settings)
+	issues := checkComments(comments, settings)
 	sortIssues(issues)
 
 	return issues, nil