check whether accounts and snapshots are using the same path

validator/Cargo.toml

@@ -69,10 +69,13 @@ thiserror = { workspace = true }
 tokio = { workspace = true }
 
 [dev-dependencies]
+assert_cmd = { workspace = true }
+predicates = { workspace = true }
 solana-account-decoder = { workspace = true }
 solana-inline-spl = { workspace = true }
 solana-runtime = { workspace = true, features = ["dev-context-only-utils"] }
 spl-token-2022 = { workspace = true, features = ["no-entrypoint"] }
+tempfile = { workspace = true }
 
 [target.'cfg(not(target_env = "msvc"))'.dependencies]
 jemallocator = { workspace = true }

validator/src/main.rs

@@ -1549,6 +1549,21 @@ pub fn main() {
         } else {
             vec![ledger_path.join("accounts")]
         };
+
+    let snapshots_dir = if let Some(snapshots) = matches.value_of("snapshots") {
+        Path::new(snapshots)
+    } else {
+        &ledger_path
+    };
+
+    // they have the same subdirectory name, "snapshot". try to catch the directory collision error earlier
+    for account_path in account_paths.iter() {
+        if account_path.as_path() == snapshots_dir {
+            eprintln!("Please provide different values for --accounts and --snapshots");
+            exit(1);
+        }
+    }
+
     let account_paths = create_and_canonicalize_directories(account_paths).unwrap_or_else(|err| {
         eprintln!("Unable to access account path: {err}");
         exit(1);
@@ -1589,12 +1604,6 @@ pub fn main() {
     let maximum_snapshot_download_abort =
         value_t_or_exit!(matches, "maximum_snapshot_download_abort", u64);
 
-    let snapshots_dir = if let Some(snapshots) = matches.value_of("snapshots") {
-        Path::new(snapshots)
-    } else {
-        &ledger_path
-    };
-
     let bank_snapshots_dir = snapshots_dir.join("snapshots");
     fs::create_dir_all(&bank_snapshots_dir).unwrap_or_else(|err| {
         eprintln!(

validator/tests/cli.rs

@@ -0,0 +1,36 @@
+use {
+    assert_cmd::prelude::*,
+    solana_sdk::signer::keypair::{write_keypair_file, Keypair},
+    std::process::Command,
+    tempfile::TempDir,
+};
+
+#[test]
+fn test_use_the_same_path_for_accounts_and_snapshots() {
+    let temp_dir = TempDir::new().unwrap();
+    let temp_dir_path = temp_dir.path();
+
+    let id_json_path = temp_dir_path.join("id.json");
+    let id_json_str = id_json_path.to_str().unwrap();
+
+    let keypair = Keypair::new();
+    write_keypair_file(&keypair, id_json_str).unwrap();
+
+    let temp_dir_str = temp_dir_path.to_str().unwrap();
+
+    let mut cmd = Command::cargo_bin(env!("CARGO_PKG_NAME")).unwrap();
+    cmd.args([
+        "--identity",
+        id_json_str,
+        "--log",
+        "-",
+        "--no-voting",
+        "--accounts",
+        temp_dir_str,
+        "--snapshots",
+        temp_dir_str,
+    ]);
+    cmd.assert().failure().stderr(predicates::str::contains(
+        "Please provide different values for --accounts and --snapshots",
+    ));
+}