From 1c25ce235794177ad33bc4de65eec8467c9663c6 Mon Sep 17 00:00:00 2001
From: Michal R <vad.sol@proton.me>
Date: Fri, 5 Dec 2025 21:05:43 +0100
Subject: [PATCH] ci/lint: Use the Rust nightly date as a cache prefix

Using the nightly date prevents reusing caches from older toolchains,
reducing unnecessary downloads and avoiding wasted cache space.
---
 .github/workflows/ci.yml | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index d8c33e73..d460f402 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -27,7 +27,15 @@ jobs:
       # Installed *after* nightly so it is the default.
       - uses: dtolnay/rust-toolchain@stable
 
+      - id: nightly-prefix
+        run: |
+          set -euo pipefail
+          prefix="$(rustc +nightly --version --verbose | awk '/commit-date/ {print "nightly-" $2}')"
+          echo "value=$prefix" >> "$GITHUB_OUTPUT"
+
       - uses: Swatinem/rust-cache@v2
+        with:
+          prefix-key: ${{ steps.nightly-prefix.outputs.value }}
 
       - uses: taiki-e/install-action@v2
         with: