Add maybe clone flag to solana-test-validator

add --maybe-clone, which silently ignores accounts to be cloned, rather than dying

test-validator/src/lib.rs

@@ -260,17 +260,26 @@ impl TestValidatorGenesis {
         self
     }
 
-    pub fn clone_accounts<T>(&mut self, addresses: T, rpc_client: &RpcClient) -> &mut Self
+    pub fn clone_accounts<T>(
+        &mut self,
+        addresses: T,
+        rpc_client: &RpcClient,
+        skip_missing: bool,
+    ) -> &mut Self
     where
         T: IntoIterator<Item = Pubkey>,
     {
         for address in addresses {
             info!("Fetching {} over RPC...", address);
-            let account = rpc_client.get_account(&address).unwrap_or_else(|err| {
-                error!("Failed to fetch {}: {}", address, err);
+            let res = rpc_client.get_account(&address);
+            if let Ok(account) = res {
+                self.add_account(address, AccountSharedData::from(account));
+            } else if skip_missing {
+                warn!("Could not find {}, skipping.", address);
+            } else {
+                error!("Failed to fetch {}: {}", address, res.unwrap_err());
                 solana_core::validator::abort();
-            });
-            self.add_account(address, AccountSharedData::from(account));
+            }
         }
         self
     }

validator/src/bin/solana-test-validator.rs

@@ -296,6 +296,20 @@ fn main() {
                      If the ledger already exists then this parameter is silently ignored",
                 ),
         )
+        .arg(
+            Arg::with_name("maybe_clone_account")
+                .long("maybe-clone")
+                .value_name("ADDRESS")
+                .takes_value(true)
+                .validator(is_pubkey_or_keypair)
+                .multiple(true)
+                .requires("json_rpc_url")
+                .help(
+                    "Copy an account from the cluster referenced by the --url argument, \
+                     skipping it if it doesn't exist. \
+                     If the ledger already exists then this parameter is silently ignored",
+                ),
+        )
         .arg(
             Arg::with_name("warp_slot")
                 .required(false)
@@ -533,6 +547,10 @@ fn main() {
         .map(|v| v.into_iter().collect())
         .unwrap_or_default();
 
+    let accounts_to_maybe_clone: HashSet<_> = pubkeys_of(&matches, "maybe_clone_account")
+        .map(|v| v.into_iter().collect())
+        .unwrap_or_default();
+
     let warp_slot = if matches.is_present("warp_slot") {
         Some(match matches.value_of("warp_slot") {
             Some(_) => value_t_or_exit!(matches, "warp_slot", Slot),
@@ -687,6 +705,17 @@ fn main() {
             cluster_rpc_client
                 .as_ref()
                 .expect("bug: --url argument missing?"),
+            false,
+        );
+    }
+
+    if !accounts_to_maybe_clone.is_empty() {
+        genesis.clone_accounts(
+            accounts_to_maybe_clone,
+            cluster_rpc_client
+                .as_ref()
+                .expect("bug: --url argument missing?"),
+            true,
         );
     }