From 355a5b5caca13d8b10f1ad8bdfe1a09d527dde36 Mon Sep 17 00:00:00 2001
From: Bogdan Opanchuk <bogdan@opanchuk.net>
Date: Fri, 15 Nov 2024 11:47:54 -0800
Subject: [PATCH] Add a wrapping type for `run_sync()` output

---
 examples/src/simple.rs           |  9 ++++--
 examples/src/simple_chain.rs     |  9 ++++--
 examples/src/simple_malicious.rs | 12 ++++++--
 manul/benches/empty_rounds.rs    |  8 ++---
 manul/src/session/transcript.rs  | 44 ++++++++++++++++++++++++++
 manul/src/testing/run_sync.rs    | 53 ++++++++++++++++++++++++++------
 manul/src/tests/partial_echo.rs  |  8 ++---
 7 files changed, 116 insertions(+), 27 deletions(-)

diff --git a/examples/src/simple.rs b/examples/src/simple.rs
index 777186c..93ea482 100644
--- a/examples/src/simple.rs
+++ b/examples/src/simple.rs
@@ -429,10 +429,13 @@ mod tests {
             .map(|signer| (signer, SimpleProtocolEntryPoint::new(all_ids.clone())))
             .collect::<Vec<_>>();
 
-        let reports = run_sync_with_tracing::<_, TestSessionParams<BinaryFormat>>(&mut OsRng, entry_points).unwrap();
+        let results = run_sync_with_tracing::<_, TestSessionParams<BinaryFormat>>(&mut OsRng, entry_points)
+            .unwrap()
+            .results()
+            .unwrap();
 
-        for (_id, report) in reports {
-            assert_eq!(report.result().unwrap(), 3); // 0 + 1 + 2
+        for (_id, result) in results {
+            assert_eq!(result, 3); // 0 + 1 + 2
         }
     }
 }
diff --git a/examples/src/simple_chain.rs b/examples/src/simple_chain.rs
index 0a85c6d..236c40c 100644
--- a/examples/src/simple_chain.rs
+++ b/examples/src/simple_chain.rs
@@ -87,10 +87,13 @@ mod tests {
             .map(|signer| (signer, DoubleSimpleEntryPoint::new(all_ids.clone())))
             .collect::<Vec<_>>();
 
-        let reports = run_sync_with_tracing::<_, TestSessionParams<BinaryFormat>>(&mut OsRng, entry_points).unwrap();
+        let results = run_sync_with_tracing::<_, TestSessionParams<BinaryFormat>>(&mut OsRng, entry_points)
+            .unwrap()
+            .results()
+            .unwrap();
 
-        for (_id, report) in reports {
-            assert_eq!(report.result().unwrap(), 3); // 0 + 1 + 2
+        for (_id, result) in results {
+            assert_eq!(result, 3); // 0 + 1 + 2
         }
     }
 }
diff --git a/examples/src/simple_malicious.rs b/examples/src/simple_malicious.rs
index 016f035..efc6761 100644
--- a/examples/src/simple_malicious.rs
+++ b/examples/src/simple_malicious.rs
@@ -93,7 +93,9 @@ fn serialized_garbage() {
         })
         .collect::<Vec<_>>();
 
-    let mut reports = run_sync_with_tracing::<_, TestSessionParams<BinaryFormat>>(&mut OsRng, entry_points).unwrap();
+    let mut reports = run_sync_with_tracing::<_, TestSessionParams<BinaryFormat>>(&mut OsRng, entry_points)
+        .unwrap()
+        .reports;
 
     let v0 = signers[0].verifying_key();
     let v1 = signers[1].verifying_key();
@@ -130,7 +132,9 @@ fn attributable_failure() {
         })
         .collect::<Vec<_>>();
 
-    let mut reports = run_sync_with_tracing::<_, TestSessionParams<BinaryFormat>>(&mut OsRng, entry_points).unwrap();
+    let mut reports = run_sync_with_tracing::<_, TestSessionParams<BinaryFormat>>(&mut OsRng, entry_points)
+        .unwrap()
+        .reports;
 
     let v0 = signers[0].verifying_key();
     let v1 = signers[1].verifying_key();
@@ -167,7 +171,9 @@ fn attributable_failure_round2() {
         })
         .collect::<Vec<_>>();
 
-    let mut reports = run_sync_with_tracing::<_, TestSessionParams<BinaryFormat>>(&mut OsRng, entry_points).unwrap();
+    let mut reports = run_sync_with_tracing::<_, TestSessionParams<BinaryFormat>>(&mut OsRng, entry_points)
+        .unwrap()
+        .reports;
 
     let v0 = signers[0].verifying_key();
     let v1 = signers[1].verifying_key();
diff --git a/manul/benches/empty_rounds.rs b/manul/benches/empty_rounds.rs
index a0ec8bd..3e19da6 100644
--- a/manul/benches/empty_rounds.rs
+++ b/manul/benches/empty_rounds.rs
@@ -195,8 +195,8 @@ fn bench_empty_rounds(c: &mut Criterion) {
             assert!(
                 run_sync::<_, TestSessionParams<BinaryFormat>>(&mut OsRng, entry_points_no_echo.clone())
                     .unwrap()
-                    .into_values()
-                    .all(|report| report.result().is_some())
+                    .results()
+                    .is_ok()
             )
         })
     });
@@ -225,8 +225,8 @@ fn bench_empty_rounds(c: &mut Criterion) {
             assert!(
                 run_sync::<_, TestSessionParams<BinaryFormat>>(&mut OsRng, entry_points_echo.clone())
                     .unwrap()
-                    .into_values()
-                    .all(|report| report.result().is_some())
+                    .results()
+                    .is_ok()
             );
         })
     });
diff --git a/manul/src/session/transcript.rs b/manul/src/session/transcript.rs
index 6739ee0..17cd4c6 100644
--- a/manul/src/session/transcript.rs
+++ b/manul/src/session/transcript.rs
@@ -1,6 +1,8 @@
 use alloc::{
     collections::{btree_map::Entry, BTreeMap, BTreeSet},
     format,
+    string::String,
+    vec::Vec,
 };
 use core::fmt::Debug;
 
@@ -183,6 +185,21 @@ pub enum SessionOutcome<P: Protocol> {
     Terminated,
 }
 
+impl<P> SessionOutcome<P>
+where
+    P: Protocol,
+{
+    /// Returns a brief description of the outcome.
+    pub fn brief(&self) -> String {
+        match self {
+            Self::Result(result) => format!("Success ({result:?})"),
+            Self::NotEnoughMessages => "Not enough messages to finalize, terminated".into(),
+            Self::Terminated => "Terminated by the user".into(),
+            Self::StalledWithProof(_) => "Unattributable failure during finalization".into(),
+        }
+    }
+}
+
 /// The report of a session execution.
 #[derive(Debug)]
 pub struct SessionReport<P: Protocol, SP: SessionParameters> {
@@ -217,4 +234,31 @@ where
             _ => None,
         }
     }
+
+    /// Returns a brief description of report.
+    pub fn brief(&self) -> String {
+        let provable_errors = self
+            .provable_errors
+            .iter()
+            .map(|(id, evidence)| format!("  {:?}: {}", id, evidence.description()))
+            .collect::<Vec<_>>();
+        let unprovable_errors = self
+            .unprovable_errors
+            .iter()
+            .map(|(id, error)| format!("  {:?}: {}", id, error))
+            .collect::<Vec<_>>();
+        let missing_messages = self
+            .missing_messages
+            .iter()
+            .map(|(id, parties)| format!("  {:?}: {:?}", id, parties))
+            .collect::<Vec<_>>();
+
+        format!(
+            "Result: {}\nProvable errors:\n{}\nUnprovable errors:\n{}\nMissing_messages:\n{}",
+            self.outcome.brief(),
+            provable_errors.join("\n"),
+            unprovable_errors.join("\n"),
+            missing_messages.join("\n")
+        )
+    }
 }
diff --git a/manul/src/testing/run_sync.rs b/manul/src/testing/run_sync.rs
index 431e7ef..6109ef1 100644
--- a/manul/src/testing/run_sync.rs
+++ b/manul/src/testing/run_sync.rs
@@ -1,4 +1,4 @@
-use alloc::{collections::BTreeMap, vec::Vec};
+use alloc::{collections::BTreeMap, format, string::String, vec::Vec};
 
 use rand::Rng;
 use rand_core::CryptoRngCore;
@@ -9,8 +9,8 @@ use tracing_subscriber::EnvFilter;
 use crate::{
     protocol::{EntryPoint, Protocol},
     session::{
-        CanFinalize, LocalError, Message, RoundAccumulator, RoundOutcome, Session, SessionId, SessionParameters,
-        SessionReport,
+        CanFinalize, LocalError, Message, RoundAccumulator, RoundOutcome, Session, SessionId, SessionOutcome,
+        SessionParameters, SessionReport,
     },
 };
 
@@ -93,7 +93,7 @@ where
 pub fn run_sync<EP, SP>(
     rng: &mut impl CryptoRngCore,
     entry_points: Vec<(SP::Signer, EP)>,
-) -> Result<BTreeMap<SP::Verifier, SessionReport<EP::Protocol, SP>>, LocalError>
+) -> Result<ExecutionResult<EP::Protocol, SP>, LocalError>
 where
     EP: EntryPoint<SP::Verifier>,
     SP: SessionParameters,
@@ -156,25 +156,24 @@ where
         }
     }
 
-    let mut outcomes = BTreeMap::new();
+    let mut reports = BTreeMap::new();
     for (verifier, state) in states {
-        let outcome = match state {
+        let report = match state {
             State::InProgress { session, accum } => session.terminate(accum)?,
             State::Finished(report) => report,
         };
-        outcomes.insert(verifier, outcome);
+        reports.insert(verifier, report);
     }
 
-    Ok(outcomes)
+    Ok(ExecutionResult { reports })
 }
 
 /// Same as [`run_sync()`], but enables a [`tracing`] subscriber that prints the tracing events to stdout,
 /// taking options from the environment variable `RUST_LOG` (see [`mod@tracing_subscriber::fmt`] for details).
-#[allow(clippy::type_complexity)]
 pub fn run_sync_with_tracing<EP, SP>(
     rng: &mut impl CryptoRngCore,
     entry_points: Vec<(SP::Signer, EP)>,
-) -> Result<BTreeMap<SP::Verifier, SessionReport<EP::Protocol, SP>>, LocalError>
+) -> Result<ExecutionResult<EP::Protocol, SP>, LocalError>
 where
     EP: EntryPoint<SP::Verifier>,
     SP: SessionParameters,
@@ -185,3 +184,37 @@ where
         .finish();
     tracing::subscriber::with_default(subscriber, || run_sync::<EP, SP>(rng, entry_points))
 }
+
+/// The result of a protocol execution on a set of nodes.
+#[derive(Debug)]
+pub struct ExecutionResult<P: Protocol, SP: SessionParameters> {
+    pub reports: BTreeMap<SP::Verifier, SessionReport<P, SP>>,
+}
+
+impl<P, SP> ExecutionResult<P, SP>
+where
+    P: Protocol,
+    SP: SessionParameters,
+{
+    pub fn results(self) -> Result<BTreeMap<SP::Verifier, P::Result>, String> {
+        let mut report_strings = Vec::new();
+        let mut results = BTreeMap::new();
+
+        for (id, report) in self.reports.into_iter() {
+            match report.outcome {
+                SessionOutcome::Result(result) => {
+                    results.insert(id, result);
+                }
+                _ => {
+                    report_strings.push(format!("Id: {:?}\n{}", id, report.brief()));
+                }
+            }
+        }
+
+        if report_strings.is_empty() {
+            Ok(results)
+        } else {
+            Err(report_strings.join("\n"))
+        }
+    }
+}
diff --git a/manul/src/tests/partial_echo.rs b/manul/src/tests/partial_echo.rs
index 4560829..9969a16 100644
--- a/manul/src/tests/partial_echo.rs
+++ b/manul/src/tests/partial_echo.rs
@@ -213,8 +213,8 @@ fn partial_echo() {
 
     let entry_points = vec![node0, node1, node2, node3, node4];
 
-    let reports = run_sync_with_tracing::<_, TestSessionParams<BinaryFormat>>(&mut OsRng, entry_points).unwrap();
-    for (_id, report) in reports {
-        assert!(report.result().is_some());
-    }
+    let _results = run_sync_with_tracing::<_, TestSessionParams<BinaryFormat>>(&mut OsRng, entry_points)
+        .unwrap()
+        .results()
+        .unwrap();
 }