fix: store tokio runtime to avoid races when installing compilers

dapp/src/lib.rs

@@ -13,6 +13,7 @@ use std::{
     collections::{BTreeMap, HashMap},
     path::{Path, PathBuf},
 };
+use tokio::runtime::Runtime;
 
 /// Re-export of the Rust EVM for convenience
 pub use evm;
@@ -310,6 +311,7 @@ struct SolcBuilder<'a> {
     lib_paths: &'a [String],
     versions: Vec<Version>,
     releases: Vec<Version>,
+    runtime: Runtime,
 }
 
 use semver::{Version, VersionReq};
@@ -323,13 +325,15 @@ impl<'a> SolcBuilder<'a> {
         lib_paths: &'a [String],
     ) -> Result<Self> {
         let versions = svm::installed_versions().unwrap_or_default();
-        let releases = tokio::runtime::Runtime::new()?.block_on(svm::all_versions())?;
+        let runtime = tokio::runtime::Runtime::new()?;
+        let releases = runtime.block_on(svm::all_versions())?;
         Ok(Self {
             contracts,
             remappings,
             lib_paths,
             versions,
             releases,
+            runtime,
         })
     }
 
@@ -405,10 +409,7 @@ impl<'a> SolcBuilder<'a> {
                     .map(|version| {
                         println!("Installing {}", version);
                         // Blocking call to install it over RPC.
-                        tokio::runtime::Runtime::new()
-                            .unwrap()
-                            .block_on(svm::install(&version))
-                            .unwrap();
+                        self.runtime.block_on(svm::install(&version)).unwrap();
                         self.versions.push(version.clone());
                         println!("Done!");
                         version