From 17e2fe425168e675fe7607182615e50527eedf53 Mon Sep 17 00:00:00 2001
From: Brad Zacher <brad.zacher@gmail.com>
Date: Thu, 2 Apr 2020 17:30:40 -0700
Subject: [PATCH] Update: Improve error message for fatal fixer errors (#13120)

---
 lib/rule-tester/rule-tester.js       | 7 ++++++-
 tests/lib/rule-tester/rule-tester.js | 2 +-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/lib/rule-tester/rule-tester.js b/lib/rule-tester/rule-tester.js
index 1c1737152c1..77df1def893 100644
--- a/lib/rule-tester/rule-tester.js
+++ b/lib/rule-tester/rule-tester.js
@@ -563,7 +563,12 @@ class RuleTester {
                 output = SourceCodeFixer.applyFixes(code, messages).output;
                 const errorMessageInFix = linter.verify(output, config, filename).find(m => m.fatal);
 
-                assert(!errorMessageInFix, `A fatal parsing error occurred in autofix: ${errorMessageInFix && errorMessageInFix.message}`);
+                assert(!errorMessageInFix, [
+                    "A fatal parsing error occurred in autofix.",
+                    `Error: ${errorMessageInFix && errorMessageInFix.message}`,
+                    "Autofix output:",
+                    output
+                ].join("\n"));
             } else {
                 output = code;
             }
diff --git a/tests/lib/rule-tester/rule-tester.js b/tests/lib/rule-tester/rule-tester.js
index 65a06da85d9..fedc237d64c 100644
--- a/tests/lib/rule-tester/rule-tester.js
+++ b/tests/lib/rule-tester/rule-tester.js
@@ -1829,7 +1829,7 @@ describe("RuleTester", () => {
                     invalid: []
                 }
             );
-        }, /A fatal parsing error occurred in autofix/u);
+        }, /A fatal parsing error occurred in autofix.\nError: .+\nAutofix output:\n.+/u);
     });
 
     describe("sanitize test cases", () => {