Use startup_file to force a standardized repos option during testing

crates/ark/src/fixtures/dummy_frontend.rs

@@ -31,6 +31,7 @@ struct DummyArkFrontendOptions {
     r_environ: bool,
     session_mode: SessionMode,
     default_repos: DefaultRepos,
+    startup_file: Option<String>,
 }
 
 /// Wrapper around `DummyArkFrontend` that uses `SessionMode::Notebook`
@@ -110,7 +111,7 @@ impl DummyArkFrontend {
                 connection_file,
                 Some(registration_file),
                 r_args,
-                None,
+                options.startup_file,
                 options.session_mode,
                 false,
                 options.default_repos,
@@ -182,20 +183,27 @@ impl DerefMut for DummyArkFrontendNotebook {
 impl DummyArkFrontendDefaultRepos {
     /// Lock a frontend with a default repos setting.
     ///
+    /// NOTE: `startup_file` is required because you typically want
+    /// to force `options(repos =)` to a fixed value for testing, regardless
+    /// of what the caller's default `repos` are set as (i.e. rig typically
+    /// sets it to a non-`@CRAN@` value).
+    ///
     /// NOTE: Only one `DummyArkFrontend` variant should call `lock()` within
     /// a given process.
-    pub fn lock(default_repos: DefaultRepos) -> Self {
-        Self::init(default_repos);
+    pub fn lock(default_repos: DefaultRepos, startup_file: String) -> Self {
+        Self::init(default_repos, startup_file);
 
         Self {
             inner: DummyArkFrontend::lock(),
         }
     }
 
     /// Initialize with given default repos
-    fn init(default_repos: DefaultRepos) {
+    fn init(default_repos: DefaultRepos, startup_file: String) {
         let mut options = DummyArkFrontendOptions::default();
         options.default_repos = default_repos;
+        options.startup_file = Some(startup_file);
+
         FRONTEND.get_or_init(|| Arc::new(Mutex::new(DummyArkFrontend::init(options))));
     }
 }
@@ -263,6 +271,7 @@ impl Default for DummyArkFrontendOptions {
             r_environ: false,
             session_mode: SessionMode::Console,
             default_repos: DefaultRepos::Auto,
+            startup_file: None,
         }
     }
 }

crates/ark/src/repos.rs

@@ -111,7 +111,7 @@ fn apply_default_repos_auto() -> anyhow::Result<()> {
 }
 
 /// On Windows, we just use the RStudio CRAN mirror as the default.
-#[cfg(windows)]
+#[cfg(not(unix))]
 fn apply_default_repos_auto() -> anyhow::Result<()> {
     apply_default_repos(DefaultRepos::RStudio)
 }

crates/ark/tests/repos-auto.rs

@@ -5,14 +5,26 @@
 //
 //
 
+use std::io::Write;
+
 use amalthea::fixtures::dummy_frontend::ExecuteRequestOptions;
 use ark::fixtures::DummyArkFrontendDefaultRepos;
 
 /// Using the automatic repos setting, the default CRAN repo should be set to the global RStudio
 /// CRAN mirror.
 #[test]
 fn test_auto_repos() {
-    let frontend = DummyArkFrontendDefaultRepos::lock(ark::repos::DefaultRepos::Auto);
+    // Use a startup file to force a standardized `repos` on startup,
+    // regardless of what your local R version has set (i.e. from rig)
+    let contents = r#"options(repos = c(CRAN = "@CRAN@"))"#;
+    let mut startup_file = tempfile::NamedTempFile::new().unwrap();
+    write!(startup_file, "{contents}").unwrap();
+    let startup_path = startup_file.path();
+
+    let frontend = DummyArkFrontendDefaultRepos::lock(
+        ark::repos::DefaultRepos::Auto,
+        startup_path.to_str().unwrap().to_string(),
+    );
 
     let code = r#"getOption("repos")[["CRAN"]]"#;
     frontend.send_execute_request(code, ExecuteRequestOptions::default());

crates/ark/tests/repos-conf-file.rs

@@ -9,20 +9,30 @@ use std::io::Write;
 use amalthea::fixtures::dummy_frontend::ExecuteRequestOptions;
 use ark::fixtures::DummyArkFrontendDefaultRepos;
 
-/// Using a configuration file, set the default CRAN repo to a custom value.
+/// Using a configuration file, set the default CRAN repo to a custom value,
+/// and add an extra internal repo.
 #[test]
 fn test_conf_file_repos() {
     let contents = r#"# Custom CRAN repo configuration file
 
 CRAN=https://my.cran.mirror/
 Internal=https://internal.cran.mirror/
 "#;
-    let mut file = tempfile::NamedTempFile::new().unwrap();
-    write!(file, "{contents}").unwrap();
+    let mut conf_file = tempfile::NamedTempFile::new().unwrap();
+    write!(conf_file, "{contents}").unwrap();
+    let conf_path = conf_file.path();
 
-    let path = file.path();
-    let frontend =
-        DummyArkFrontendDefaultRepos::lock(ark::repos::DefaultRepos::ConfFile(path.to_path_buf()));
+    // Use a startup file to force a standardized `repos` on startup,
+    // regardless of what your local R version has set (i.e. from rig)
+    let contents = r#"options(repos = c(CRAN = "@CRAN@"))"#;
+    let mut startup_file = tempfile::NamedTempFile::new().unwrap();
+    write!(startup_file, "{contents}").unwrap();
+    let startup_path = startup_file.path();
+
+    let frontend = DummyArkFrontendDefaultRepos::lock(
+        ark::repos::DefaultRepos::ConfFile(conf_path.to_path_buf()),
+        startup_path.to_str().unwrap().to_string(),
+    );
 
     let code = r#"getOption("repos")[["CRAN"]]"#;
     frontend.send_execute_request(code, ExecuteRequestOptions::default());
@@ -37,5 +47,20 @@ Internal=https://internal.cran.mirror/
 
     frontend.recv_iopub_idle();
 
+    assert_eq!(frontend.recv_shell_execute_reply(), input.execution_count);
+
+    let code = r#"getOption("repos")[["Internal"]]"#;
+    frontend.send_execute_request(code, ExecuteRequestOptions::default());
+    frontend.recv_iopub_busy();
+
+    let input = frontend.recv_iopub_execute_input();
+    assert_eq!(input.code, code);
+    assert_eq!(
+        frontend.recv_iopub_execute_result(),
+        r#"[1] "https://internal.cran.mirror/""#
+    );
+
+    frontend.recv_iopub_idle();
+
     assert_eq!(frontend.recv_shell_execute_reply(), input.execution_count)
 }