fix(getblocktemplate): change error format in proposals (#6044)

* change error format in proposals

* use trim_matches

* make regex feature dependency

* remove regex fully

* remove char in comment to leave the file as it was before

* remove assertion lines from snapshots

zebra-rpc/src/methods/get_block_template_rpcs/types/get_block_template/proposal.rs

@@ -2,7 +2,7 @@
 //!
 //! `ProposalResponse` is the output of the `getblocktemplate` RPC method in 'proposal' mode.
 
-use std::{error::Error, num::ParseIntError, str::FromStr, sync::Arc};
+use std::{num::ParseIntError, str::FromStr, sync::Arc};
 
 use zebra_chain::{
     block::{self, Block, Height},
@@ -42,23 +42,21 @@ pub enum ProposalResponse {
 
 impl ProposalResponse {
     /// Return a rejected response containing an error kind and detailed error info.
-    pub fn rejected<S: ToString>(kind: S, error: BoxError) -> Self {
+    ///
-        let kind = kind.to_string();
+    /// Note: Error kind is currently ignored to match zcashd error format (`kebab-case` string).
+    pub fn rejected<S: ToString>(_kind: S, error: BoxError) -> Self {
+        // Make error `kebab-case` to match zcashd format.
+        let error_kebab1 = format!("{error:?}")
+            .replace(|c: char| !c.is_alphanumeric(), "-")
+            .to_ascii_lowercase();
+        // Remove consecutive duplicated `-` characters.
+        let mut error_v: Vec<char> = error_kebab1.chars().collect();
+        error_v.dedup_by(|a, b| a == &'-' && b == &'-');
+        let error_kebab2: String = error_v.into_iter().collect();
+        // Trim any leading or trailing `-` characters.
+        let final_error = error_kebab2.trim_matches('-');
 
-        // Pretty-print the detailed error for now
+        ProposalResponse::Rejected(final_error.to_string())
-        ProposalResponse::Rejected(format!("{kind}: {error:#?}"))
-    }
-
-    /// Return a rejected response containing just the detailed error information.
-    pub fn error(error: BoxError) -> Self {
-        // Pretty-print the detailed error for now
-        ProposalResponse::Rejected(format!("{error:#?}"))
-    }
-}
-
-impl<E: Error + Send + Sync + 'static> From<E> for ProposalResponse {
-    fn from(error: E) -> Self {
-        Self::error(error.into())
     }
 }
 

zebra-rpc/src/methods/tests/snapshot/snapshots/get_block_template_invalid-proposal@mainnet_10.snap

@@ -2,4 +2,4 @@
 source: zebra-rpc/src/methods/tests/snapshot/get_block_template_rpcs.rs
 expression: block_template
 ---
-"invalid proposal format: Io(\n    Error {\n        kind: UnexpectedEof,\n        message: \"failed to fill whole buffer\",\n    },\n)"
+"io-error-kind-unexpectedeof-message-failed-to-fill-whole-buffer"

zebra-rpc/src/methods/tests/snapshot/snapshots/get_block_template_invalid-proposal@testnet_10.snap

@@ -2,4 +2,4 @@
 source: zebra-rpc/src/methods/tests/snapshot/get_block_template_rpcs.rs
 expression: block_template
 ---
-"invalid proposal format: Io(\n    Error {\n        kind: UnexpectedEof,\n        message: \"failed to fill whole buffer\",\n    },\n)"
+"io-error-kind-unexpectedeof-message-failed-to-fill-whole-buffer"