From 25c50e7837fdd8d739c4d4d2c3e4f4377f5ec214 Mon Sep 17 00:00:00 2001
From: Adi Dahiya <adi.dahiya14@gmail.com>
Date: Thu, 28 Feb 2019 21:26:08 -0500
Subject: [PATCH 1/2] Fix regression in CheckstyleFormatter backwards
 compatibility (#4561)

---
 src/formatters/checkstyleFormatter.ts       | 8 ++++++--
 src/language/formatter/abstractFormatter.ts | 4 ++--
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/src/formatters/checkstyleFormatter.ts b/src/formatters/checkstyleFormatter.ts
index ce5746f8948..5b687910bc4 100644
--- a/src/formatters/checkstyleFormatter.ts
+++ b/src/formatters/checkstyleFormatter.ts
@@ -38,8 +38,8 @@ export class Formatter extends AbstractFormatter {
     };
     /* tslint:enable:object-literal-sort-keys */
 
-    public format(failures: RuleFailure[], _fixes: RuleFailure[], fileNames: string[]): string {
-        const groupedFailures: { [k: string]: RuleFailure[] } = {};
+    public format(failures: RuleFailure[], _fixes?: RuleFailure[], fileNames?: string[]): string {
+        const groupedFailures: { [fileName: string]: RuleFailure[] } = {};
         for (const failure of failures) {
             const fileName = failure.getFileName();
             if (groupedFailures[fileName] !== undefined) {
@@ -49,6 +49,10 @@ export class Formatter extends AbstractFormatter {
             }
         }
 
+        if (fileNames === undefined) {
+            fileNames = Object.keys(groupedFailures);
+        }
+
         const formattedFiles = fileNames.map(fileName => {
             const formattedFailures =
                 groupedFailures[fileName] !== undefined
diff --git a/src/language/formatter/abstractFormatter.ts b/src/language/formatter/abstractFormatter.ts
index 69529774d27..2a6ff3f7e78 100644
--- a/src/language/formatter/abstractFormatter.ts
+++ b/src/language/formatter/abstractFormatter.ts
@@ -23,8 +23,8 @@ export abstract class AbstractFormatter implements IFormatter {
     public static metadata: IFormatterMetadata;
     public abstract format(
         failures: RuleFailure[],
-        fixes: RuleFailure[],
-        fileNames: string[],
+        fixes?: RuleFailure[],
+        fileNames?: string[],
     ): string;
 
     protected sortFailures(failures: RuleFailure[]): RuleFailure[] {

From 10bc210e391de034d9b582498f3546b7fd254590 Mon Sep 17 00:00:00 2001
From: Adi Dahiya <adi.dahiya14@gmail.com>
Date: Thu, 28 Feb 2019 21:27:45 -0500
Subject: [PATCH 2/2] Prepare release v5.13.1

---
 CHANGELOG.md  | 4 ++++
 package.json  | 2 +-
 src/linter.ts | 2 +-
 3 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 288c01560be..73d4562a5ec 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Change Log
 
+## v5.13.1
+
+- [bugfix] Fix regression in CheckstyleFormatter backwards compatibility (#4561)
+
 ## v5.13.0
 
 - [deprecation] Mark `RuleWalker` and `ProgramAwareRuleWalker` as deprecated (#4413)
diff --git a/package.json b/package.json
index b61d0ecfd7c..ce2da92222f 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
     "name": "tslint",
-    "version": "5.13.0",
+    "version": "5.13.1",
     "description": "An extensible static analysis linter for the TypeScript language",
     "bin": {
         "tslint": "./bin/tslint"
diff --git a/src/linter.ts b/src/linter.ts
index 322c358dc6f..2edbab9c398 100644
--- a/src/linter.ts
+++ b/src/linter.ts
@@ -42,7 +42,7 @@ import { arrayify, dedent, flatMap, mapDefined } from "./utils";
  * Linter that can lint multiple files in consecutive runs.
  */
 export class Linter {
-    public static VERSION = "5.13.0";
+    public static VERSION = "5.13.1";
 
     public static findConfiguration = findConfiguration;
     public static findConfigurationPath = findConfigurationPath;