From 2e41106866ee7253f800d589a40f61105cec524e Mon Sep 17 00:00:00 2001
From: Solaris-star <820622658@qq.com>
Date: Fri, 24 Jul 2026 00:09:25 +0800
Subject: [PATCH] docs: document how to run tests without a go.mod

This package intentionally has no module file. Note the temporary
`go mod init` workflow and `-vet=off` requirement for local testing (#249).

Fixes #249
---
 README.md | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/README.md b/README.md
index 54dfdcb1..e9a0b709 100644
--- a/README.md
+++ b/README.md
@@ -57,3 +57,16 @@ Before sending a PR, please discuss your change by raising an issue.
 ## License
 
 BSD-2-Clause
+
+## Running tests
+
+This package predates modules and intentionally has no `go.mod` (zero dependencies).
+From a checkout, initialize a temporary module for local testing:
+
+```bash
+go mod init github.com/pkg/errors
+go test -vet=off ./...
+```
+
+`-vet=off` is needed because a few tests intentionally pass non-constant format
+strings into `Wrapf` / `WithMessagef`.