actions: test {upload,download}-artifacts@v4 support

If Forgejo version is >= 7.0 and Forgejo runner > 3.3.0 artifacts@v4
are tested to work with a forked modified version that claims to be
compatible.

actions/actions.sh

@@ -76,6 +76,16 @@ function actions_teardown() {
     stop_daemon forgejo
 }
 
+function actions_runner_version() {
+    local runner_version=$($DIR/forgejo-runner --version | sed -n -e 's/forgejo-runner version v//p')
+    if test -z "$runner_version" ; then
+	$DIR/forgejo-runner --version
+	echo failed to parse version
+	false
+    fi
+    echo $runner_version
+}
+
 function test_actions() {
     local versions="${1:-1.20 1.21 $RELEASE_NUMBERS_AND_DEV}"
 
@@ -84,6 +94,13 @@ function test_actions() {
 	log_info "Testing actions for $version"
 
 	actions_setup $version
+	local runner_version=$(actions_runner_version)
+
+	if dpkg --compare-versions $version gt 7.0 && dpkg --compare-versions $runner_version gt 3.3.0 ; then
+	    for example in artifacts-v4 ; do
+		run actions_verify_example $example
+	    done
+	fi
 
 	for example in echo checkout service container expression local-action docker-action if if-fail ; do
 	    run actions_verify_example $example

actions/example-artifacts-v4/.forgejo/workflows/test.yml

@@ -0,0 +1,47 @@
+on: [push]
+jobs:
+  upload-many:
+    runs-on: docker
+    steps:
+    - run: mkdir -p artifacts
+
+    - run: touch artifacts/ONE artifacts/TWO
+
+    - uses: https://code.forgejo.org/forgejo/upload-artifact@v4
+      with:
+        name: many-artifacts
+        path: artifacts/
+
+  download-many:
+    needs: [upload-many]
+    runs-on: docker
+    steps:
+    - uses: https://code.forgejo.org/forgejo/download-artifact@v4
+
+    - run: |
+        test -f many-artifacts/ONE
+        test -f many-artifacts/TWO
+
+  upload-one:
+    runs-on: docker
+    steps:
+    - run: mkdir -p path/to/artifact
+
+    - run: echo hello > path/to/artifact/world.txt
+
+    - uses: https://code.forgejo.org/forgejo/upload-artifact@v4
+      with:
+        name: my-artifact
+        path: path/to/artifact/world.txt
+
+  download-one:
+    needs: [upload-one]
+    runs-on: docker
+    steps:
+    - run: "! test -f world.txt"
+
+    - uses: https://code.forgejo.org/forgejo/download-artifact@v4
+      with:
+        name: my-artifact
+
+    - run: "test -f world.txt"