feat(cast): decode-event with local and openchain API (foundry-rs#9431)

Author: grandizzy

crates/cast/bin/args.rs

@@ -533,8 +533,9 @@ pub enum CastSubcommand {
     /// Decode event data.
     #[command(visible_aliases = &["event-decode", "--event-decode", "ed"])]
     DecodeEvent {
-        /// The event signature.
-        sig: String,
+        /// The event signature. If none provided then tries to decode from local cache or `https://api.openchain.xyz`.
+        #[arg(long, visible_alias = "event-sig")]
+        sig: Option<String>,
         /// The event data to decode.
         data: String,
     },

crates/cast/bin/main.rs

@@ -213,8 +213,29 @@ async fn main_args(args: CastArgs) -> Result<()> {
             print_tokens(&tokens);
         }
         CastSubcommand::DecodeEvent { sig, data } => {
-            let event = get_event(sig.as_str())?;
-            let decoded_event = event.decode_log_parts(None, &hex::decode(data)?, false)?;
+            let decoded_event = if let Some(event_sig) = sig {
+                get_event(event_sig.as_str())?.decode_log_parts(None, &hex::decode(data)?, false)?
+            } else {
+                let data = data.strip_prefix("0x").unwrap_or(data.as_str());
+                let selector = data.get(..64).unwrap_or_default();
+                let identified_event =
+                    SignaturesIdentifier::new(Config::foundry_cache_dir(), false)?
+                        .write()
+                        .await
+                        .identify_event(&hex::decode(selector)?)
+                        .await;
+                if let Some(event) = identified_event {
+                    let _ = sh_println!("{}", event.signature());
+                    let data = data.get(64..).unwrap_or_default();
+                    get_event(event.signature().as_str())?.decode_log_parts(
+                        None,
+                        &hex::decode(data)?,
+                        false,
+                    )?
+                } else {
+                    eyre::bail!("No matching event signature found for selector `{selector}`")
+                }
+            };
             print_tokens(&decoded_event.body);
         }
         CastSubcommand::DecodeError { sig, data } => {

crates/cast/tests/cli/main.rs

@@ -1539,15 +1539,35 @@ casttest!(string_decode, |_prj, cmd| {
 "#]]);
 });
 
-casttest!(event_decode, |_prj, cmd| {
-    cmd.args(["decode-event", "MyEvent(uint256,address)", "0x000000000000000000000000000000000000000000000000000000000000004e0000000000000000000000000000000000000000000000000000000000d0004f"]).assert_success().stdout_eq(str![[r#"
+// tests cast can decode event with provided signature
+casttest!(event_decode_with_sig, |_prj, cmd| {
+    cmd.args(["decode-event", "--sig", "MyEvent(uint256,address)", "0x000000000000000000000000000000000000000000000000000000000000004e0000000000000000000000000000000000000000000000000000000000d0004f"]).assert_success().stdout_eq(str![[r#"
 78
 0x0000000000000000000000000000000000D0004F
 
+"#]]);
+
+    cmd.args(["--json"]).assert_success().stdout_eq(str![[r#"
+[
+  "78",
+  "0x0000000000000000000000000000000000D0004F"
+]
+
 "#]]);
 });
 
-// tests cast can decode traces with provided signature
+// tests cast can decode event with Openchain API
+casttest!(event_decode_with_openchain, |prj, cmd| {
+    prj.clear_cache();
+    cmd.args(["decode-event", "0xe27c4c1372396a3d15a9922f74f9dfc7c72b1ad6d63868470787249c356454c1000000000000000000000000000000000000000000000000000000000000004e00000000000000000000000000000000000000000000000000000dd00000004e"]).assert_success().stdout_eq(str![[r#"
+BaseCurrencySet(address,uint256)
+0x000000000000000000000000000000000000004e
+15187004358734 [1.518e13]
+
+"#]]);
+});
+
+// tests cast can decode error with provided signature
 casttest!(error_decode_with_sig, |_prj, cmd| {
     cmd.args(["decode-error", "--sig", "AnotherValueTooHigh(uint256,address)", "0x7191bc6200000000000000000000000000000000000000000000000000000000000000650000000000000000000000000000000000000000000000000000000000D0004F"]).assert_success().stdout_eq(str![[r#"
 101
@@ -1564,8 +1584,9 @@ casttest!(error_decode_with_sig, |_prj, cmd| {
 "#]]);
 });
 
-// tests cast can decode traces with Openchain API
-casttest!(error_decode_with_openchain, |_prj, cmd| {
+// tests cast can decode error with Openchain API
+casttest!(error_decode_with_openchain, |prj, cmd| {
+    prj.clear_cache();
     cmd.args(["decode-error", "0x7a0e198500000000000000000000000000000000000000000000000000000000000000650000000000000000000000000000000000000000000000000000000000000064"]).assert_success().stdout_eq(str![[r#"
 ValueTooHigh(uint256,uint256)
 101
@@ -1574,14 +1595,16 @@ ValueTooHigh(uint256,uint256)
 "#]]);
 });
 
-// tests cast can decode traces when using local sig identifiers cache
-forgetest!(error_decode_with_cache, |prj, cmd| {
+// tests cast can decode error and event when using local sig identifiers cache
+forgetest!(error_event_decode_with_cache, |prj, cmd| {
+    prj.clear_cache();
     foundry_test_utils::util::initialize(prj.root());
     prj.add_source(
         "LocalProjectContract",
         r#"
 contract ContractWithCustomError {
     error AnotherValueTooHigh(uint256, address);
+    event MyUniqueEventWithinLocalProject(uint256 a, address b);
 }
    "#,
     )
@@ -1598,6 +1621,16 @@ AnotherValueTooHigh(uint256,address)
 101
 0x0000000000000000000000000000000000D0004F
 
+"#]]);
+    // Assert cast can decode event with local cache.
+    cmd.cast_fuse()
+        .args(["decode-event", "0xbd3699995dcc867b64dbb607be2c33be38df9134bef1178df13bfb9446e73104000000000000000000000000000000000000000000000000000000000000004e00000000000000000000000000000000000000000000000000000dd00000004e"])
+        .assert_success()
+        .stdout_eq(str![[r#"
+MyUniqueEventWithinLocalProject(uint256,address)
+78
+0x00000000000000000000000000000DD00000004e
+
 "#]]);
 });