Test solving multiple models in parallel

.github/workflows/build_and_test.yml

@@ -25,10 +25,18 @@ jobs:
           wget --quiet --no-check-certificate https://github.com/scipopt/scip/releases/download/$(echo "v${{env.version}}" | tr -d '.')/SCIPOptSuite-${{ env.version }}-Linux-ubuntu.deb
           sudo apt-get update && sudo apt install -y ./SCIPOptSuite-${{ env.version }}-Linux-ubuntu.deb
 
-      - name: Install tarpaulin
-        run: cargo install cargo-tarpaulin
-      - name: Run tests
-        run: cargo tarpaulin --verbose --all --out Xml
+      - name: Install rust stable toolchain
+        uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+          override: true
+
+      - name: Run cargo-tarpaulin
+        uses: actions-rs/[email protected]
+        with:
+          version: '0.15.0'
+          args: '--verbose --all --out Xml'
+
       - name: Upload to codecov.io
         uses: codecov/codecov-action@v2
         with:

Cargo.toml

@@ -14,3 +14,6 @@ raw = []
 [dependencies]
 scip-sys =  "0.1.4"
 doc-comment = "0.3.3"
+
+[dev-dependencies]
+rayon = "1.5.1"

src/model.rs

@@ -206,7 +206,7 @@ impl Model<ProblemCreated> {
             .set_cons_modifiable(cons, modifiable)
             .expect("Failed to set constraint modifiable");
     }
-    
+
     /// Informs the SCIP instance that the objective value is always integral and returns the same `Model` instance.
     pub fn set_obj_integral(mut self) -> Self {
         self.scip
@@ -1040,11 +1040,11 @@ impl From<ObjSense> for ffi::SCIP_OBJSENSE {
 
 #[cfg(test)]
 mod tests {
+    use crate::status::Status;
+    use rayon::prelude::*;
     use std::fs;
     use std::path::Path;
 
-    use crate::status::Status;
-
     use super::*;
 
     #[test]
@@ -1437,4 +1437,17 @@ mod tests {
 
         assert_eq!(model.status(), Status::TimeLimit);
     }
+
+    #[test]
+    fn test_thread_safety() {
+        let statuses = (0..1000)
+            .into_par_iter()
+            .map(|_| {
+                let model = create_model().hide_output().solve();
+                model.status()
+            })
+            .collect::<Vec<_>>();
+
+        assert!(statuses.iter().all(|&s| s == Status::Optimal));
+    }
 }