test: serialised extension dumping

hugr-cli/src/lib.rs

@@ -18,7 +18,7 @@ pub enum CliArgs {
     /// Validate and visualize a HUGR file.
     Validate(validate::CliArgs),
     /// Write standard extensions out in serialized form.
-    GenExtension(extensions::ExtArgs),
+    GenExtensions(extensions::ExtArgs),
     /// External commands
     #[command(external_subcommand)]
     External(Vec<OsString>),

hugr-cli/src/main.rs

@@ -9,7 +9,7 @@ use clap_verbosity_flag::Level;
 fn main() {
     match CliArgs::parse() {
         CliArgs::Validate(args) => run_validate(args),
-        CliArgs::GenExtension(args) => args.run_dump(),
+        CliArgs::GenExtensions(args) => args.run_dump(),
         CliArgs::External(_) => {
             // TODO: Implement support for external commands.
             // Running `hugr COMMAND` would look for `hugr-COMMAND` in the path

hugr-cli/tests/gen_extensions.rs

@@ -0,0 +1,41 @@
+//! Tests for the CLI extension writing.
+//!
+//! Miri is globally disabled for these tests because they mostly involve
+//! calling the CLI binary, which Miri doesn't support.
+#![cfg(all(test, not(miri)))]
+
+use assert_cmd::Command;
+use rstest::{fixture, rstest};
+
+#[fixture]
+fn cmd() -> Command {
+    let mut cmd = Command::cargo_bin("hugr").unwrap();
+    cmd.arg("gen-extensions");
+    cmd
+}
+
+#[rstest]
+fn test_extension_dump(mut cmd: Command) {
+    let temp_dir = assert_fs::TempDir::new()
+        .expect("temp dir creation failure.")
+        .into_persistent_if(std::env::var_os("HUGR_CLI_TEST_PERSIST_FILES").is_some());
+    cmd.arg("-o");
+    cmd.arg(temp_dir.path());
+    cmd.assert().success();
+
+    let expected_paths = [
+        "logic.json",
+        "prelude.json",
+        "ptr.json",
+        "arithmetic/int/types.json",
+        "arithmetic/float/types.json",
+        "arithmetic/int.json",
+        "arithmetic/float.json",
+        "arithmetic/conversions.json",
+    ];
+    // check all paths exist
+    for path in expected_paths.iter() {
+        let full_path = temp_dir.join(path);
+        assert!(full_path.exists());
+    }
+}