1 files changed, 86 insertions, 24 deletions

diff --git a/runtime/resolve_addr.rs b/runtime/resolve_addr.rs
index c3dc52f8f..d4f500802 100644
--- a/runtime/resolve_addr.rs
+++ b/runtime/resolve_addr.rs
@@ -1,29 +1,45 @@
 // Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
 
 use deno_core::error::AnyError;
+use deno_core::error::Context;
 use std::net::SocketAddr;
 use std::net::ToSocketAddrs;
+use tokio::net::lookup_host;
 
-/// Resolve network address. Returns a future.
-pub fn resolve_addr(hostname: &str, port: u16) -> Result<SocketAddr, AnyError> {
+/// Resolve network address *asynchronously*.
+pub async fn resolve_addr(
+  hostname: &str,
+  port: u16,
+) -> Result<SocketAddr, AnyError> {
+  let addr_port_pair = make_addr_port_pair(hostname, port);
+  lookup_host(addr_port_pair)
+    .await?
+    .next()
+    .context("No resolved address found")
+}
+
+/// Resolve network address *synchronously*.
+pub fn resolve_addr_sync(
+  hostname: &str,
+  port: u16,
+) -> Result<SocketAddr, AnyError> {
+  let addr_port_pair = make_addr_port_pair(hostname, port);
+  addr_port_pair
+    .to_socket_addrs()?
+    .next()
+    .context("No resolved address found")
+}
+
+fn make_addr_port_pair(hostname: &str, port: u16) -> (&str, u16) {
   // Default to localhost if given just the port. Example: ":80"
-  let addr: &str = if !hostname.is_empty() {
-    &hostname
-  } else {
-    "0.0.0.0"
-  };
+  if hostname.is_empty() {
+    return ("0.0.0.0", port);
+  }
 
   // If this looks like an ipv6 IP address. Example: "[2001:db8::1]"
   // Then we remove the brackets.
-  let addr = if addr.starts_with('[') && addr.ends_with(']') {
-    let l = addr.len() - 1;
-    addr.get(1..l).unwrap()
-  } else {
-    addr
-  };
-  let addr_port_pair = (addr, port);
-  let mut iter = addr_port_pair.to_socket_addrs()?;
-  Ok(iter.next().unwrap())
+  let addr = hostname.trim_start_matches('[').trim_end_matches(']');
+  (addr, port)
 }
 
 #[cfg(test)]
@@ -34,39 +50,85 @@ mod tests {
   use std::net::SocketAddrV4;
   use std::net::SocketAddrV6;
 
+  #[tokio::test]
+  async fn resolve_addr1() {
+    let expected =
+      SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 80));
+    let actual = resolve_addr("127.0.0.1", 80).await.unwrap();
+    assert_eq!(actual, expected);
+  }
+
+  #[tokio::test]
+  async fn resolve_addr2() {
+    let expected =
+      SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(0, 0, 0, 0), 80));
+    let actual = resolve_addr("", 80).await.unwrap();
+    assert_eq!(actual, expected);
+  }
+
+  #[tokio::test]
+  async fn resolve_addr3() {
+    let expected =
+      SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(192, 0, 2, 1), 25));
+    let actual = resolve_addr("192.0.2.1", 25).await.unwrap();
+    assert_eq!(actual, expected);
+  }
+
+  #[tokio::test]
+  async fn resolve_addr_ipv6() {
+    let expected = SocketAddr::V6(SocketAddrV6::new(
+      Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0, 1),
+      8080,
+      0,
+      0,
+    ));
+    let actual = resolve_addr("[2001:db8::1]", 8080).await.unwrap();
+    assert_eq!(actual, expected);
+  }
+
+  #[tokio::test]
+  async fn resolve_addr_err() {
+    assert!(resolve_addr("INVALID ADDR", 1234).await.is_err());
+  }
+
   #[test]
-  fn resolve_addr1() {
+  fn resolve_addr_sync1() {
     let expected =
       SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 80));
-    let actual = resolve_addr("127.0.0.1", 80).unwrap();
+    let actual = resolve_addr_sync("127.0.0.1", 80).unwrap();
     assert_eq!(actual, expected);
   }
 
   #[test]
-  fn resolve_addr2() {
+  fn resolve_addr_sync2() {
     let expected =
       SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(0, 0, 0, 0), 80));
-    let actual = resolve_addr("", 80).unwrap();
+    let actual = resolve_addr_sync("", 80).unwrap();
     assert_eq!(actual, expected);
   }
 
   #[test]
-  fn resolve_addr3() {
+  fn resolve_addr_sync3() {
     let expected =
       SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(192, 0, 2, 1), 25));
-    let actual = resolve_addr("192.0.2.1", 25).unwrap();
+    let actual = resolve_addr_sync("192.0.2.1", 25).unwrap();
     assert_eq!(actual, expected);
   }
 
   #[test]
-  fn resolve_addr_ipv6() {
+  fn resolve_addr_sync_ipv6() {
     let expected = SocketAddr::V6(SocketAddrV6::new(
       Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0, 1),
       8080,
       0,
       0,
     ));
-    let actual = resolve_addr("[2001:db8::1]", 8080).unwrap();
+    let actual = resolve_addr_sync("[2001:db8::1]", 8080).unwrap();
     assert_eq!(actual, expected);
   }
+
+  #[test]
+  fn resolve_addr_sync_err() {
+    assert!(resolve_addr_sync("INVALID ADDR", 1234).is_err());
+  }
 }