From f4dd649ebad094ee266c0dab01f66c5381dcd3ab Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Sawicz?= <michal@sawicz.net>
Date: Wed, 27 Jan 2021 10:12:13 +0100
Subject: [PATCH 1/3] Add `channel` input

---
 action.yml | 4 ++++
 index.js   | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/action.yml b/action.yml
index da39586..fa077eb 100644
--- a/action.yml
+++ b/action.yml
@@ -3,6 +3,10 @@ author: Samuel Meuli
 description: GitHub Action for setting up Snapcraft
 
 inputs:
+  channel:
+    description: The channel to install Snapcraft from
+    required: true
+    default: stable
   snapcraft_token:
     description: Token for logging into Snapcraft
     required: true
diff --git a/index.js b/index.js
index 8663c6d..b8f5ab9 100644
--- a/index.js
+++ b/index.js
@@ -33,7 +33,7 @@ const getPlatform = () => {
  */
 const runLinuxInstaller = () => {
 	const useLxd = process.env.INPUT_USE_LXD === "true";
-	run("sudo snap install snapcraft --classic");
+	run(`sudo snap install snapcraft --classic --channel ${process.env.INPUT_CHANNEL}`);
 	if (useLxd) {
 		run("sudo snap install lxd");
 		run(`sudo usermod --append --groups lxd ${process.env.USER}`);

From db5eee9d766f70081715a642f465b49beeb4ed23 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Sawicz?= <michal@sawicz.net>
Date: Wed, 27 Jan 2021 10:20:12 +0100
Subject: [PATCH 2/3] Add tests for `channel` input

---
 .github/workflows/test.yml | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 6ae4781..80fd683 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -22,6 +22,10 @@ jobs:
       - name: Snapcraft should be installed on macOS/Ubuntu
         if: startsWith(matrix.os, 'macos') || startsWith(matrix.os, 'ubuntu')
         run: snapcraft --version
+      - name: Snapcraft should track the `stable` channel on Linux
+        if: startsWith(matrix.os, 'ubuntu')
+        shell: bash
+        run: snap info snapcraft | grep -q 'tracking:\s\+latest/stable'
       - name: Snapcraft should not be installed on Windows
         if: startsWith(matrix.os, 'windows')
         shell: bash
@@ -46,6 +50,20 @@ jobs:
       - name: User should be logged in
         run: snapcraft whoami
 
+  # Install with channel
+  install-channel:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out Git repository
+        uses: actions/checkout@v1
+      - name: Run action
+        uses: ./
+        with:
+          channel: candidate
+      - name: Snapcraft should track the `candidate` channel on Linux
+        shell: bash
+        run: snap info snapcraft | grep -q 'tracking:\s\+latest/candidate'
+
   # Install with lxd
   lxd:
     runs-on: ${{ matrix.os }}

From 1c4c409cb4613cd19e0d5ec13b076531e16e284d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Sawicz?= <michal@sawicz.net>
Date: Sat, 27 Feb 2021 10:27:11 +0100
Subject: [PATCH 3/3] Make `channel` optional

Co-authored-by: Casper da Costa-Luis <casper.dcl@physics.org>
---
 action.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/action.yml b/action.yml
index fa077eb..5b48355 100644
--- a/action.yml
+++ b/action.yml
@@ -5,7 +5,7 @@ description: GitHub Action for setting up Snapcraft
 inputs:
   channel:
     description: The channel to install Snapcraft from
-    required: true
+    required: false
     default: stable
   snapcraft_token:
     description: Token for logging into Snapcraft