From a5304715647814ba43fd97141f94a9ee83e25964 Mon Sep 17 00:00:00 2001
From: Owen Jacobson <owen@grimoire.ca>
Date: Fri, 31 Jul 2020 13:52:17 -0400
Subject: Automate periodic Rust Nightly upgrades.

This allows the project to have a pinned version of Rust, but also ensures we don't fall too far behind on versions so long as someone (cough) reviews the pull requests regularly. This splits the difference between using nightly directly (and having Travis fail sporadically because of missing rustfmt/clippy) and pinning so that Travis works reliably (and having a large version lag).
---
 .github/workflows/nightly-rust-update.yml | 29 +++++++++++++++++++++++++++++
 rust-toolchain                            |  2 +-
 2 files changed, 30 insertions(+), 1 deletion(-)
 create mode 100644 .github/workflows/nightly-rust-update.yml

diff --git a/.github/workflows/nightly-rust-update.yml b/.github/workflows/nightly-rust-update.yml
new file mode 100644
index 0000000..c7dc962
--- /dev/null
+++ b/.github/workflows/nightly-rust-update.yml
@@ -0,0 +1,29 @@
+name: Update Rust nightly
+on:
+    workflow_dispatch:
+    schedule:
+        # Nothing magic here, I just wanted to avoid the midnight thundering
+        # herd on the first of each month.
+        - cron: '0 5 8 * *'
+
+jobs:
+    nightly-update:
+        name: Update Rust nightly
+        runs-on: ubuntu-latest
+        steps:
+            - uses: actions/checkout@v2
+            - run: date +nightly-%Y-%m-%d > rust-toolchain
+            - run: rustup install --profile minimal "$(< rust-toolchain)"
+            - run: rustup component add clippy rustfmt
+            - run: cargo install cargo-udeps
+            - run: tools/checks
+            - uses: peter-evans/create-pull-request@v3
+              with:
+                commit-message: Update Rust nightly version.
+                branch: rust-nightly-update
+                title: Update Rust nightly version
+                body: |
+                    If these changes look good, merge this pull request to
+                    update to the latest Nightly as of today.
+                    
+                    Automatically generated by the nightly-rust-update workflow.
diff --git a/rust-toolchain b/rust-toolchain
index 4eabcfe..4aec5c6 100644
--- a/rust-toolchain
+++ b/rust-toolchain
@@ -1 +1 @@
-nightly-2020-07-26
+nightly-2020-06-10
-- 
cgit v1.2.3