From 897fc186cef0ac400146e7e9cc4c99c4ba69dd90 Mon Sep 17 00:00:00 2001
From: Arthur Fontaine <0arthur.fontaine@gmail.com>
Date: Wed, 10 Dec 2025 16:01:44 +0100
Subject: [PATCH] Display error .cause property

fixes #3186
---
 lib/reporters/colors.js  |  3 +++
 lib/reporters/default.js | 11 +++++++++++
 lib/serialize-error.js   |  3 ++-
 3 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/lib/reporters/colors.js b/lib/reporters/colors.js
index 644e897df..4c6397eea 100644
--- a/lib/reporters/colors.js
+++ b/lib/reporters/colors.js
@@ -34,6 +34,9 @@ const colors = {
 	get stack() {
 		return chalk.red;
 	},
+	get cause() {
+		return chalk.cyan;
+	},
 	get information() {
 		return chalk.magenta;
 	},
diff --git a/lib/reporters/default.js b/lib/reporters/default.js
index 10ca84f65..fd7584fc2 100644
--- a/lib/reporters/default.js
+++ b/lib/reporters/default.js
@@ -463,6 +463,17 @@ export default class Reporter {
 			}
 		}
 
+		const hasCause = error.cause instanceof Object && (error.cause.message || error.cause.stack);
+    if (hasCause) {
+			const {cause} = error;
+      this.lineWriter.writeLine(colors.cause('Cause:'));
+      this.lineWriter.writeLine(colors.cause(cause.message ?? ''));
+      if (cause.stack) {
+        this.lineWriter.writeLine(colors.cause(cause.stack));
+      }
+      this.lineWriter.writeLine();
+    }
+
 		let summary = '';
 		let printStack = true;
 		if (error.type === 'native') {
diff --git a/lib/serialize-error.js b/lib/serialize-error.js
index ca47a6350..55db25465 100644
--- a/lib/serialize-error.js
+++ b/lib/serialize-error.js
@@ -61,12 +61,13 @@ export default function serializeError(error, {testFile = null} = {}) {
 		};
 	}
 
-	const {message, name, stack} = error;
+	const {message, name, stack, cause} = error;
 	const base = {
 		message,
 		name,
 		originalError: error, // Note that the main process receives a structured clone.
 		stack,
+		cause,
 	};
 
 	if (!isAvaAssertionError(error)) {