Support --version / -V on the command-line tool

src/main.rs

@@ -8,7 +8,7 @@ use rustls::{ClientConfig, RootCertStore};
 use webpki_roots::TLS_SERVER_ROOTS;
 
 #[derive(Parser)]
-#[command(name = "diffed-places-pipeline")]
+#[command(name = "diffed-places-pipeline", version)]
 struct Cli {
     #[command(subcommand)]
     command: Option<Commands>,

tests/integration_test.rs

@@ -35,3 +35,14 @@ fn test_no_subcommand() {
         .failure()
         .stderr(predicates::str::contains("no subcommand given"));
 }
+
+#[test]
+fn test_version_flag() {
+    // Asserts against CARGO_PKG_VERSION (rather than a hardcoded string) so
+    // this doesn't need updating every time cut-release.sh bumps the version.
+    Command::new(cargo_bin!("osm-diffs"))
+        .arg("--version")
+        .assert()
+        .success()
+        .stdout(predicates::str::contains(env!("CARGO_PKG_VERSION")));
+}