refactor(test): Let OS assign a port and pass it through the channel

binary-install/tests/all/cache.rs

@@ -23,8 +23,6 @@ fn it_returns_none_if_install_is_not_permitted() {
 
 #[test]
 fn it_downloads_tarball() {
-    let server_port = 7880;
-    let url = format!("http://{}:{}", utils::TEST_SERVER_HOST, server_port);
     let binary_name = "wasm-pack";
     let binaries = vec![binary_name];
 
@@ -32,7 +30,9 @@ fn it_downloads_tarball() {
     let tarball = utils::create_tarball(binary_name).ok();
 
     // Spin up a local TcpListener.
-    utils::start_server(server_port, tarball).recv().unwrap();
+    let server_port = utils::start_server(tarball, None).recv().unwrap();
+
+    let url = format!("http://{}:{}", utils::TEST_SERVER_HOST, server_port);
 
     let dir = tempfile::TempDir::new().unwrap();
     let cache = Cache::at(dir.path());
@@ -70,17 +70,17 @@ fn it_returns_error_when_it_failed_to_download() {
 
 #[test]
 fn it_returns_error_when_it_failed_to_extract_tarball() {
-    let server_port = 7882;
-    let url = format!("http://{}:{}", utils::TEST_SERVER_HOST, server_port);
     let binary_name = "wasm-pack";
     let binaries = vec![binary_name];
 
     let dir = tempfile::TempDir::new().unwrap();
     let cache = Cache::at(dir.path());
-    let full_url = &format!("{}/{}.tar.gz", &url, binary_name);
 
     // Spin up a local TcpListener.
-    utils::start_server(server_port, None).recv().unwrap();
+    let server_port = utils::start_server(None, None).recv().unwrap();
+
+    let url = format!("http://{}:{}", utils::TEST_SERVER_HOST, server_port);
+    let full_url = &format!("{}/{}.tar.gz", &url, binary_name);
 
     let dl = cache.download(true, binary_name, &binaries, full_url);
 
@@ -93,17 +93,17 @@ fn it_returns_error_when_it_failed_to_extract_tarball() {
 
 #[test]
 fn it_returns_error_when_it_failed_to_extract_zip() {
-    let server_port = 7883;
-    let url = format!("http://{}:{}", utils::TEST_SERVER_HOST, server_port);
     let binary_name = "wasm-pack";
     let binaries = vec![binary_name];
 
     let dir = tempfile::TempDir::new().unwrap();
     let cache = Cache::at(dir.path());
-    let full_url = &format!("{}/{}.zip", &url, binary_name);
 
     // Spin up a local TcpListener.
-    utils::start_server(server_port, None).recv().unwrap();
+    let server_port = utils::start_server(None, None).recv().unwrap();
+
+    let url = format!("http://{}:{}", utils::TEST_SERVER_HOST, server_port);
+    let full_url = &format!("{}/{}.zip", &url, binary_name);
 
     let dl = cache.download(true, binary_name, &binaries, full_url);
 
@@ -118,16 +118,17 @@ fn it_returns_error_when_it_failed_to_extract_zip() {
 #[should_panic(expected = "don't know how to extract http://localhost:7884/wasm-pack.bin")]
 fn it_panics_if_not_tarball_or_zip() {
     let server_port = 7884;
-    let url = format!("http://{}:{}", utils::TEST_SERVER_HOST, server_port);
     let binary_name = "wasm-pack";
     let binaries = vec![binary_name];
 
     let dir = tempfile::TempDir::new().unwrap();
     let cache = Cache::at(dir.path());
-    let full_url = &format!("{}/{}.bin", &url, binary_name);
 
     // Spin up a local TcpListener.
-    utils::start_server(server_port, None).recv().unwrap();
+    utils::start_server(None, Some(server_port)).recv().unwrap();
+
+    let url = format!("http://{}:{}", utils::TEST_SERVER_HOST, server_port);
+    let full_url = &format!("{}/{}.bin", &url, binary_name);
 
     let _ = cache.download(true, binary_name, &binaries, full_url);
 }

binary-install/tests/all/utils/mod.rs

@@ -8,36 +8,40 @@ use std::thread;
 
 pub const TEST_SERVER_HOST: &'static str = "localhost";
 
-pub fn start_server(port: u32, tarball: Option<Vec<u8>>) -> Receiver<()> {
+pub fn start_server(tarball: Option<Vec<u8>>, server_port: Option<u16>) -> Receiver<u16> {
     let (sender, receiver) = channel();
 
     thread::spawn(move || {
-        TcpListener::bind(format!("{}:{}", TEST_SERVER_HOST, port))
-            .map(|listener| {
-                sender.send(()).unwrap();
+        TcpListener::bind(format!(
+            "{}:{}",
+            TEST_SERVER_HOST,
+            server_port.unwrap_or_else(|| 0)
+        ))
+        .map(|listener| {
+            sender.send(listener.local_addr().unwrap().port()).unwrap();
 
-                for stream in listener.incoming() {
-                    let mut stream = stream.unwrap();
+            for stream in listener.incoming() {
+                let mut stream = stream.unwrap();
 
-                    let mut buffer = [0; 512];
+                let mut buffer = [0; 512];
 
-                    stream.read(&mut buffer).unwrap();
+                stream.read(&mut buffer).unwrap();
 
-                    let response = "HTTP/1.1 200 OK\r\n\r\n";
+                let response = "HTTP/1.1 200 OK\r\n\r\n";
 
-                    stream.write(response.as_bytes()).unwrap();
+                stream.write(response.as_bytes()).unwrap();
 
-                    match tarball.to_owned() {
-                        Some(tar) => {
-                            stream.write(tar.as_ref()).unwrap();
-                        }
-                        None => {}
+                match tarball.to_owned() {
+                    Some(tar) => {
+                        stream.write(tar.as_ref()).unwrap();
                     }
-
-                    stream.flush().unwrap();
+                    None => {}
                 }
-            })
-            .unwrap();
+
+                stream.flush().unwrap();
+            }
+        })
+        .unwrap();
     });
 
     receiver