ci: add a simple test that the invocations actually pass

It is embarrassing that none of the tests caught the option parsing failure
merged in the last patch. Let's add at least a simple script that calls
the compiled binary. We can always add something more elaborate later.

Author: keszybz

.github/workflows/ci.yml

@@ -47,6 +47,8 @@ jobs:
         run: make program CARGOFLAGS="--verbose"
       - name: Run tests
         run: make check CARGOFLAGS="--verbose"
+      - name: Check program invocation
+        run: tests/test-invocations.sh target/release/zram-generator
 
   rustfmt:
     name: rustfmt

tests/test-invocations.sh

@@ -0,0 +1,42 @@
+# SPDX-License-Identifier: MIT
+set -e
+
+program=${1:?}
+
+dir=$(mktemp -d 'zram-test.XXXXXX')
+trap 'rm -r $dir' EXIT
+
+set -x
+
+$program --help
+$program --version
+
+# This should pass
+mkdir $dir/{a,b,c}
+$program $dir/{a,b,c}
+
+# Those should fail with option parsing error (2)
+set +e
+$program dir1 dir2 dir3 dir4
+ret=$?
+set -e
+test $ret -eq 2
+
+set +e
+$program dir1 --setup-device
+ret=$?
+set -e
+test $ret -eq 2
+
+# Those should fail because the device doesn't exist (1)
+set +e
+$program --setup-device /no/such/file/or/directory
+ret=$?
+set -e
+test $ret -eq 1
+
+set +e
+$program --reset-device /no/such/file/or/directory
+ret=$?
+set -e
+test $ret -eq 1