also take Impl by ref in Resolver::new

mainly for symmetry. the existing tests don't clone the subject so the
code does not become any shorter

packages/conformance-tests/src/resolver/dns/scenarios.rs

@@ -40,7 +40,7 @@ fn can_resolve() -> Result<()> {
     eprintln!("root.zone:\n{}", root_ns.zone_file());
 
     let roots = &[Root::new(root_ns.fqdn().clone(), root_ns.ipv4_addr())];
-    let resolver = Resolver::start(dns_test::subject(), roots, &TrustAnchor::empty(), &network)?;
+    let resolver = Resolver::start(&dns_test::subject(), roots, &TrustAnchor::empty(), &network)?;
     let resolver_ip_addr = resolver.ipv4_addr();
 
     let client = Client::new(&network)?;
@@ -86,7 +86,7 @@ fn nxdomain() -> Result<()> {
     let root_ns = root_ns.start()?;
 
     let roots = &[Root::new(root_ns.fqdn().clone(), root_ns.ipv4_addr())];
-    let resolver = Resolver::start(dns_test::subject(), roots, &TrustAnchor::empty(), &network)?;
+    let resolver = Resolver::start(&dns_test::subject(), roots, &TrustAnchor::empty(), &network)?;
     let resolver_ip_addr = resolver.ipv4_addr();
 
     let client = Client::new(&network)?;

packages/conformance-tests/src/resolver/dnssec/rfc4035/section_4/section_4_1.rs

@@ -11,7 +11,7 @@ fn edns_support() -> Result<()> {
     let network = &Network::new()?;
     let ns = NameServer::new(&dns_test::peer(), FQDN::ROOT, network)?.start()?;
     let resolver = Resolver::start(
-        dns_test::subject(),
+        &dns_test::subject(),
         &[Root::new(ns.fqdn().clone(), ns.ipv4_addr())],
         &TrustAnchor::empty(),
         network,

packages/conformance-tests/src/resolver/dnssec/scenarios/bogus.rs

@@ -67,7 +67,7 @@ fn bad_signature_in_leaf_nameserver() -> Result<()> {
     let roots = &[Root::new(root_ns.fqdn().clone(), root_ns.ipv4_addr())];
 
     let trust_anchor = TrustAnchor::from_iter([root_ksk.clone(), root_zsk.clone()]);
-    let resolver = Resolver::start(dns_test::subject(), roots, &trust_anchor, &network)?;
+    let resolver = Resolver::start(&dns_test::subject(), roots, &trust_anchor, &network)?;
     let resolver_addr = resolver.ipv4_addr();
 
     let client = Client::new(&network)?;

packages/conformance-tests/src/resolver/dnssec/scenarios/secure.rs

@@ -27,7 +27,7 @@ fn can_validate_without_delegation() -> Result<()> {
     let roots = &[Root::new(ns.fqdn().clone(), ns.ipv4_addr())];
 
     let trust_anchor = TrustAnchor::from_iter([root_ksk.clone(), root_zsk.clone()]);
-    let resolver = Resolver::start(dns_test::subject(), roots, &trust_anchor, &network)?;
+    let resolver = Resolver::start(&dns_test::subject(), roots, &trust_anchor, &network)?;
     let resolver_addr = resolver.ipv4_addr();
 
     let client = Client::new(&network)?;
@@ -94,7 +94,7 @@ fn can_validate_with_delegation() -> Result<()> {
     let roots = &[Root::new(root_ns.fqdn().clone(), root_ns.ipv4_addr())];
 
     let trust_anchor = TrustAnchor::from_iter([root_ksk.clone(), root_zsk.clone()]);
-    let resolver = Resolver::start(dns_test::subject(), roots, &trust_anchor, &network)?;
+    let resolver = Resolver::start(&dns_test::subject(), roots, &trust_anchor, &network)?;
     let resolver_addr = resolver.ipv4_addr();
 
     let client = Client::new(&network)?;

packages/dns-test/examples/explore.rs

@@ -50,7 +50,7 @@ fn main() -> Result<()> {
 
     let trust_anchor = TrustAnchor::from_iter([root_ksk.clone(), root_zsk.clone()]);
     println!("building docker image...");
-    let resolver = Resolver::start(dns_test::subject(), roots, &trust_anchor, &network)?;
+    let resolver = Resolver::start(&dns_test::subject(), roots, &trust_anchor, &network)?;
     println!("DONE\n\n");
 
     let resolver_addr = resolver.ipv4_addr();

packages/dns-test/src/resolver.rs

@@ -21,7 +21,7 @@ impl Resolver {
     ///
     /// This constructor panics if `roots` is an empty slice
     pub fn start(
-        implementation: Implementation,
+        implementation: &Implementation,
         roots: &[Root],
         trust_anchor: &TrustAnchor,
         network: &Network,
@@ -127,7 +127,7 @@ mod tests {
         let network = Network::new()?;
         let ns = NameServer::new(&Implementation::Unbound, FQDN::ROOT, &network)?.start()?;
         let resolver = Resolver::start(
-            Implementation::Unbound,
+            &Implementation::Unbound,
             &[Root::new(ns.fqdn().clone(), ns.ipv4_addr())],
             &TrustAnchor::empty(),
             &network,

packages/dns-test/src/tshark.rs

@@ -312,7 +312,7 @@ mod tests {
 
         let roots = &[Root::new(root_ns.fqdn().clone(), root_ns.ipv4_addr())];
         let resolver = Resolver::start(
-            Implementation::Unbound,
+            &Implementation::Unbound,
             roots,
             &TrustAnchor::empty(),
             network,