Add escape hatch in r_task() for unit tests

Author: lionel-

crates/ark/src/r_task.rs

@@ -10,17 +10,16 @@ use std::{
     time::Duration,
 };
 
+use crate::interface::{RMain, R_MAIN};
+use crossbeam::channel::bounded;
 use harp::exec::safely;
+use harp::test::R_TASK_BYPASS;
+use log::info;
 
 extern "C" {
     pub static mut R_PolledEvents: Option<unsafe extern "C" fn()>;
 }
 
-use crossbeam::channel::bounded;
-use log::info;
-
-use crate::interface::{RMain, R_MAIN};
-
 type SharedOption<T> = Arc<Mutex<Option<T>>>;
 
 pub fn r_task<'env, F, T>(f: F) -> T
@@ -29,6 +28,11 @@ where
     F: 'env + Send,
     T: 'env + Send,
 {
+    // Escape hatch for unit tests
+    if unsafe { R_TASK_BYPASS } {
+        return f();
+    }
+
     let main = acquire_r_main();
 
     // Recursive case: If we're on ark-r-main already, just run the

crates/ark/tests/environment.rs

@@ -179,7 +179,7 @@ fn test_environment_list() {
         assert_eq!(Rf_length(*contents), 0);
     }
 
-    // create some more variables
+    // Create some more variables
     r_lock! {
         let sym = r_symbol!("a");
         Rf_defineVar(sym, Rf_ScalarInteger(42), test_env.sexp);
@@ -225,6 +225,6 @@ fn test_environment_list() {
     assert_eq!(update.removed, ["a"]);
     assert_eq!(update.version, 6);
 
-    // close the comm. Otherwise the thread panics
+    // Close the comm. Otherwise the thread panics
     incoming_tx.send(CommChannelMsg::Close).unwrap();
 }

crates/harp/src/test.rs

@@ -22,10 +22,17 @@ use stdext::cargs;
 
 use crate::lock::with_r_lock;
 
+// Escape hatch for unit tests
+pub static mut R_TASK_BYPASS: bool = false;
+
 static INIT: Once = Once::new();
 
 pub fn start_r() {
     INIT.call_once(|| {
+        unsafe {
+            R_TASK_BYPASS = true;
+        }
+
         // TODO: Right now, tests can fail if the version of R discovered
         // on the PATH, and the version of R that 'ark' linked to at compile
         // time, do not match. We could relax this requirement by allowing