From e4145bf08bdeb1ad6894dac51d3ab2e0d952ee9c Mon Sep 17 00:00:00 2001
From: Dario Nieuwenhuis <dirbaio@dirbaio.net>
Date: Mon, 5 Jul 2021 02:33:29 +0200
Subject: [PATCH] Deny warnings in CI

---
 .github/workflows/rust.yml | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/rust.yml b/.github/workflows/rust.yml
index f4105230..fc836dfc 100644
--- a/.github/workflows/rust.yml
+++ b/.github/workflows/rust.yml
@@ -102,8 +102,15 @@ jobs:
         with:
           path: target
           key: ${{ runner.os }}-${{ matrix.target }}
+
+      # We have to append the "-D warnings" flag to .cargo/config rather than
+      # using the RUSTFLAGS environment variable because if we set RUSTFLAGS
+      # cargo will ignore the rustflags config in .cargo/config.
       - name: Check
-        run: cd ${{ matrix.package }} &&  cargo check --features=${{ matrix.features }} --target=${{ matrix.target }}
+        run: |
+          mkdir -p .cargo
+          echo -e '[target."cfg(all())"]\nrustflags = ["-D", "warnings"]' >> .cargo/config
+          cd ${{ matrix.package }} && RUSTFLAGS=-Dwarnings cargo check --features=${{ matrix.features }} --target=${{ matrix.target }}
 
   fmt:
     runs-on: ubuntu-latest