From a3925908e47a25698eca625248e2664f37346e70 Mon Sep 17 00:00:00 2001
From: figsoda <figsoda@pm.me>
Date: Sun, 1 Aug 2021 17:01:13 -0400
Subject: doc: rust: improve documentation on cargoLock.lockFile

---
 doc/languages-frameworks/rust.section.md | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/doc/languages-frameworks/rust.section.md b/doc/languages-frameworks/rust.section.md
index f17e1ba8d8f..9de9a06465f 100644
--- a/doc/languages-frameworks/rust.section.md
+++ b/doc/languages-frameworks/rust.section.md
@@ -129,7 +129,15 @@ rustPlatform.buildRustPackage rec {
 ```
 
 This will retrieve the dependencies using fixed-output derivations from
-the specified lockfile.
+the specified lockfile. Note that setting `cargoLock.lockFile` doesn't
+add a `Cargo.lock` to your `src`, and a `Cargo.lock` is still required
+to build a rust package. A simple fix is to use:
+
+```nix
+postPatch = ''
+  cp ${./Cargo.lock} Cargo.lock
+'';
+```
 
 The output hash of each dependency that uses a git source must be
 specified in the `outputHashes` attribute. For example:
-- 
cgit 1.4.1