@typescript-eslint/ban-tslint-comment

internal/config/config.go

@@ -14,6 +14,7 @@ import (
 	"github.com/web-infra-dev/rslint/internal/plugins/typescript/rules/array_type"
 	"github.com/web-infra-dev/rslint/internal/plugins/typescript/rules/await_thenable"
 	"github.com/web-infra-dev/rslint/internal/plugins/typescript/rules/ban_ts_comment"
+	"github.com/web-infra-dev/rslint/internal/plugins/typescript/rules/ban_tslint_comment"
 	"github.com/web-infra-dev/rslint/internal/plugins/typescript/rules/ban_types"
 	"github.com/web-infra-dev/rslint/internal/plugins/typescript/rules/class_literal_property_style"
 	"github.com/web-infra-dev/rslint/internal/plugins/typescript/rules/consistent_generic_constructors"
@@ -380,6 +381,7 @@ func registerAllTypeScriptEslintPluginRules() {
 	GlobalRuleRegistry.Register("@typescript-eslint/array-type", array_type.ArrayTypeRule)
 	GlobalRuleRegistry.Register("@typescript-eslint/await-thenable", await_thenable.AwaitThenableRule)
 	GlobalRuleRegistry.Register("@typescript-eslint/ban-ts-comment", ban_ts_comment.BanTsCommentRule)
+	GlobalRuleRegistry.Register("@typescript-eslint/ban-tslint-comment", ban_tslint_comment.BanTslintCommentRule)
 	GlobalRuleRegistry.Register("@typescript-eslint/ban-types", ban_types.BanTypesRule)
 	GlobalRuleRegistry.Register("@typescript-eslint/class-literal-property-style", class_literal_property_style.ClassLiteralPropertyStyleRule)
 	GlobalRuleRegistry.Register("@typescript-eslint/consistent-generic-constructors", consistent_generic_constructors.ConsistentGenericConstructorsRule)

internal/plugins/typescript/rules/ban_tslint_comment/ban_tslint_comment.go

@@ -0,0 +1,121 @@
+package ban_tslint_comment
+
+import (
+	"regexp"
+	"strings"
+
+	"github.com/microsoft/typescript-go/shim/ast"
+	"github.com/microsoft/typescript-go/shim/core"
+	"github.com/microsoft/typescript-go/shim/scanner"
+	"github.com/web-infra-dev/rslint/internal/rule"
+	"github.com/web-infra-dev/rslint/internal/utils"
+)
+
+// tslint regex
+// https://github.com/palantir/tslint/blob/95d9d958833fd9dc0002d18cbe34db20d0fbf437/src/enableDisableRules.ts#L32
+var enableDisableRegex = regexp.MustCompile(`^\s*tslint:(enable|disable)(?:-(line|next-line))?(:|\s|$)`)
+
+// BanTslintCommentRule implements the ban-tslint-comment rule.
+// Disallows tslint directive comments like // tslint:disable
+var BanTslintCommentRule = rule.CreateRule(rule.Rule{
+	Name: "ban-tslint-comment",
+	Run:  run,
+})
+
+func run(ctx rule.RuleContext, _ any) rule.RuleListeners {
+	text := ctx.SourceFile.Text()
+
+	utils.ForEachComment(&ctx.SourceFile.Node, func(comment *ast.CommentRange) {
+		commentValue := extractCommentValue(text, comment)
+		if !enableDisableRegex.MatchString(commentValue) {
+			return
+		}
+
+		commentText := extractCommentText(text, comment)
+		if commentText == "" {
+			commentText = commentValue
+		}
+		message := rule.RuleMessage{
+			Id:          "commentDetected",
+			Description: "tslint comment detected: " + commentText,
+		}
+
+		fixRange := buildFixRange(ctx.SourceFile, comment, len(text))
+		ctx.ReportRangeWithFixes(
+			core.NewTextRange(comment.Pos(), comment.End()),
+			message,
+			rule.RuleFixRemoveRange(fixRange),
+		)
+	}, ctx.SourceFile)
+
+	return rule.RuleListeners{}
+}
+
+func extractCommentValue(text string, comment *ast.CommentRange) string {
+	if comment.Pos() < 0 || comment.End() > len(text) {
+		return ""
+	}
+
+	switch comment.Kind {
+	case ast.KindSingleLineCommentTrivia:
+		if comment.End() <= comment.Pos()+2 {
+			return ""
+		}
+		return text[comment.Pos()+2 : comment.End()]
+	case ast.KindMultiLineCommentTrivia:
+		if comment.End() <= comment.Pos()+4 {
+			return ""
+		}
+		return text[comment.Pos()+2 : comment.End()-2]
+	default:
+		return ""
+	}
+}
+
+func extractCommentText(text string, comment *ast.CommentRange) string {
+	if comment.End() <= comment.Pos() {
+		return ""
+	}
+	if comment.Pos() < 0 || comment.End() > len(text) {
+		return ""
+	}
+	return strings.TrimSpace(text[comment.Pos():comment.End()])
+}
+
+func buildFixRange(sourceFile *ast.SourceFile, comment *ast.CommentRange, textLen int) core.TextRange {
+	text := sourceFile.Text()
+	start := comment.Pos()
+	end := comment.End()
+
+	startLine, _ := scanner.GetECMALineAndCharacterOfPosition(sourceFile, start)
+	lineStart := scanner.GetECMAPositionOfLineAndCharacter(sourceFile, startLine, 0)
+
+	isStandalone := true
+	for i := lineStart; i < start; i++ {
+		if text[i] != ' ' && text[i] != '\t' {
+			isStandalone = false
+			break
+		}
+	}
+
+	if isStandalone {
+		start = lineStart
+		if end < textLen {
+			switch text[end] {
+			case '\r':
+				end++
+				if end < textLen && text[end] == '\n' {
+					end++
+				}
+			case '\n':
+				end++
+			}
+		}
+	} else {
+		for start > lineStart && (text[start-1] == ' ' || text[start-1] == '\t') {
+			start--
+		}
+	}
+
+	return core.NewTextRange(start, end)
+}

internal/plugins/typescript/rules/ban_tslint_comment/ban_tslint_comment.md

@@ -0,0 +1,27 @@
+# ban-tslint-comment
+
+## Rule Details
+
+Disallow TSLint directive comments such as `// tslint:disable` and
+`// tslint:disable-next-line`. These directives are not used by ESLint and are
+typically left behind when migrating from TSLint.
+
+Examples of **incorrect** code for this rule:
+
+```javascript
+/* tslint:disable */
+/* tslint:enable */
+// tslint:disable-next-line
+someCode(); // tslint:disable-line
+```
+
+Examples of **correct** code for this rule:
+
+```javascript
+// some other comment
+/* another comment that mentions tslint */
+```
+
+## Original Documentation
+
+- [typescript-eslint ban-tslint-comment](https://typescript-eslint.io/rules/ban-tslint-comment)

internal/plugins/typescript/rules/ban_tslint_comment/ban_tslint_comment_test.go

@@ -0,0 +1,75 @@
+package ban_tslint_comment
+
+import (
+	"testing"
+
+	"github.com/web-infra-dev/rslint/internal/plugins/typescript/rules/fixtures"
+	"github.com/web-infra-dev/rslint/internal/rule_tester"
+)
+
+func TestBanTslintCommentRule(t *testing.T) {
+	rule_tester.RunRuleTester(fixtures.GetRootDir(), "tsconfig.json", t, &BanTslintCommentRule, []rule_tester.ValidTestCase{
+		{Code: "let a: readonly any[] = [];"},
+		{Code: "let a = new Array();"},
+		{Code: "// some other comment"},
+		{Code: "// TODO: this is a comment that mentions tslint"},
+		{Code: "/* another comment that mentions tslint */"},
+	}, []rule_tester.InvalidTestCase{
+		{
+			Code: "/* tslint:disable */",
+			Errors: []rule_tester.InvalidTestCaseError{
+				{MessageId: "commentDetected", Line: 1, Column: 1},
+			},
+			Output: []string{""},
+		},
+		{
+			Code: "/* tslint:enable */",
+			Errors: []rule_tester.InvalidTestCaseError{
+				{MessageId: "commentDetected", Line: 1, Column: 1},
+			},
+			Output: []string{""},
+		},
+		{
+			Code: "/* tslint:disable:rule1 rule2 rule3... */",
+			Errors: []rule_tester.InvalidTestCaseError{
+				{MessageId: "commentDetected", Line: 1, Column: 1},
+			},
+			Output: []string{""},
+		},
+		{
+			Code: "/* tslint:enable:rule1 rule2 rule3... */",
+			Errors: []rule_tester.InvalidTestCaseError{
+				{MessageId: "commentDetected", Line: 1, Column: 1},
+			},
+			Output: []string{""},
+		},
+		{
+			Code: "// tslint:disable-next-line",
+			Errors: []rule_tester.InvalidTestCaseError{
+				{MessageId: "commentDetected", Line: 1, Column: 1},
+			},
+			Output: []string{""},
+		},
+		{
+			Code: "someCode(); // tslint:disable-line",
+			Errors: []rule_tester.InvalidTestCaseError{
+				{MessageId: "commentDetected", Line: 1, Column: 13},
+			},
+			Output: []string{"someCode();"},
+		},
+		{
+			Code: "// tslint:disable-next-line:rule1 rule2 rule3...",
+			Errors: []rule_tester.InvalidTestCaseError{
+				{MessageId: "commentDetected", Line: 1, Column: 1},
+			},
+			Output: []string{""},
+		},
+		{
+			Code: "const whoa = doSomeStuff();\n// tslint:disable-line\nconsole.log(whoa);\n",
+			Errors: []rule_tester.InvalidTestCaseError{
+				{MessageId: "commentDetected", Line: 2, Column: 1},
+			},
+			Output: []string{"const whoa = doSomeStuff();\nconsole.log(whoa);\n"},
+		},
+	})
+}

internal/plugins/typescript/rules/prefer_string_starts_ends_with/prefer_string_starts_ends_with.go

@@ -86,6 +86,9 @@ func isNumber(node *ast.Node, value int) bool {
 		if unary == nil {
 			return false
 		}
+		if unary.Operator == ast.KindPlusToken {
+			return isNumber(unary.Operand, value)
+		}
 		if unary.Operator == ast.KindMinusToken {
 			return isNumber(unary.Operand, -value)
 		}
@@ -143,7 +146,8 @@ func getStringLength(node *ast.Node) int {
 		if lit == nil {
 			return -1
 		}
-		return len(lit.Text)
+		// Match JS semantics: string length is UTF-16 code units.
+		return jsStringLength(lit.Text)
 	}
 	return -1
 }

internal/plugins/typescript/rules/prefer_string_starts_ends_with/prefer_string_starts_ends_with_test.go

@@ -384,6 +384,22 @@ function f(s: string) {
 function f(s: string) {
   s.startsWith('a');
 }
+`},
+		},
+		// s[+0] === 'a'
+		{
+			Code: `
+function f(s: string) {
+  s[+0] === 'a';
+}
+`,
+			Errors: []rule_tester.InvalidTestCaseError{
+				{MessageId: "preferStartsWith"},
+			},
+			Output: []string{`
+function f(s: string) {
+  s.startsWith('a');
+}
 `},
 		},
 		// s?.[0] === 'a'
@@ -532,6 +548,22 @@ function f(s: string) {
 function f(s: string) {
   s.startsWith('a');
 }
+`},
+		},
+		// s.charAt(+0) === 'a'
+		{
+			Code: `
+function f(s: string) {
+  s.charAt(+0) === 'a';
+}
+`,
+			Errors: []rule_tester.InvalidTestCaseError{
+				{MessageId: "preferStartsWith"},
+			},
+			Output: []string{`
+function f(s: string) {
+  s.startsWith('a');
+}
 `},
 		},
 		// s.charAt(0) !== 'a'
@@ -1028,6 +1060,22 @@ function f(s: string) {
 function f(s: string) {
   s.startsWith('bar');
 }
+`},
+		},
+		// s.slice(0, 1) === 'あ'
+		{
+			Code: `
+function f(s: string) {
+  s.slice(0, 1) === 'あ';
+}
+`,
+			Errors: []rule_tester.InvalidTestCaseError{
+				{MessageId: "preferStartsWith"},
+			},
+			Output: []string{`
+function f(s: string) {
+  s.startsWith('あ');
+}
 `},
 		},
 		// s?.slice(0, 3) === 'bar'

packages/rslint-test-tools/rstest.config.mts

@@ -19,7 +19,7 @@ export default defineConfig({
     './tests/typescript-eslint/rules/array-type.test.ts',
     './tests/typescript-eslint/rules/await-thenable.test.ts',
     // './tests/typescript-eslint/rules/ban-ts-comment.test.ts',
-    // './tests/typescript-eslint/rules/ban-tslint-comment.test.ts',
+    './tests/typescript-eslint/rules/ban-tslint-comment.test.ts',
     './tests/typescript-eslint/rules/class-literal-property-style.test.ts',
     // './tests/typescript-eslint/rules/class-methods-use-this/class-methods-use-this-core.test.ts',
     // './tests/typescript-eslint/rules/class-methods-use-this/class-methods-use-this.test.ts',