From 5b89c3482f07fed64d594a3a5f90e725b89e8f93 Mon Sep 17 00:00:00 2001
From: Klaus Meinhardt <klaus.meinhardt1@gmail.com>
Date: Fri, 1 Dec 2017 17:42:56 +0100
Subject: [PATCH] one-line: avoid crash on parse error

[bugfix] `one-line` fixed crash on syntax error on class and interface
Fixes: #3537
---
 src/rules/oneLineRule.ts             |  5 ++++-
 test/rules/one-line/all/test.ts.fix  | 13 +++++++++++++
 test/rules/one-line/all/test.ts.lint | 13 +++++++++++++
 3 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/src/rules/oneLineRule.ts b/src/rules/oneLineRule.ts
index 7c311c35f14..818b40bb0a9 100644
--- a/src/rules/oneLineRule.ts
+++ b/src/rules/oneLineRule.ts
@@ -97,7 +97,10 @@ class OneLineWalker extends Lint.AbstractWalker<Options> {
                 case ts.SyntaxKind.InterfaceDeclaration:
                 case ts.SyntaxKind.ClassDeclaration:
                 case ts.SyntaxKind.ClassExpression: {
-                    this.check(getChildOfKind(node, ts.SyntaxKind.OpenBraceToken, sourceFile)!);
+                    const openBrace = getChildOfKind(node, ts.SyntaxKind.OpenBraceToken, sourceFile);
+                    if (openBrace !== undefined) {
+                        this.check(openBrace);
+                    }
                     break;
                 }
                 case ts.SyntaxKind.IfStatement: {
diff --git a/test/rules/one-line/all/test.ts.fix b/test/rules/one-line/all/test.ts.fix
index ec67c2b0cbd..1a9d1bda0c7 100644
--- a/test/rules/one-line/all/test.ts.fix
+++ b/test/rules/one-line/all/test.ts.fix
@@ -136,3 +136,16 @@ if (true) {
 } else {
     false;
 }
+
+// don't crash on parse error
+interface InvalidInterface = {
+  foo: string,
+}
+
+class InvalidClass = {
+  foo: string,
+}
+
+foo = class InvalidClassExpression = {
+  foo: string,
+}
diff --git a/test/rules/one-line/all/test.ts.lint b/test/rules/one-line/all/test.ts.lint
index 037fd008c79..12223e901fa 100644
--- a/test/rules/one-line/all/test.ts.lint
+++ b/test/rules/one-line/all/test.ts.lint
@@ -179,3 +179,16 @@ if (true) {
  ~~~~   [missing whitespace]
     false;
 }
+
+// don't crash on parse error
+interface InvalidInterface = {
+  foo: string,
+}
+
+class InvalidClass = {
+  foo: string,
+}
+
+foo = class InvalidClassExpression = {
+  foo: string,
+}