From 6406fccd195c2e126844c9bc06337a3bed88b8b5 Mon Sep 17 00:00:00 2001
From: Bryan Helmkamp <bryan@brynary.com>
Date: Mon, 23 Feb 2026 16:09:36 -0500
Subject: [PATCH] Fix regressions from ceaa9bf: restore Fail as non-retryable
 and allow multiple terminal nodes

Revert two incorrect behavioral changes introduced in ceaa9bf:

1. StageStatus::Fail must return immediately, not retry. Fail is a
   deliberate routing outcome (e.g. to take a "fail" edge). Retrying it
   caused conditional_branching and manager_loop tests to hang.

2. Pipelines can legitimately have multiple terminal nodes. The
   "exactly one" constraint broke branching_loop_back_on_failure.
   Restore "at least one" validation.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 crates/attractor/src/engine.rs           |  3 ++-
 crates/attractor/src/validation/rules.rs | 14 +-------------
 2 files changed, 3 insertions(+), 14 deletions(-)

diff --git a/crates/attractor/src/engine.rs b/crates/attractor/src/engine.rs
index 15950065a..f57f991ce 100644
--- a/crates/attractor/src/engine.rs
+++ b/crates/attractor/src/engine.rs
@@ -604,10 +604,11 @@ impl PipelineEngine {
             match outcome.status {
                 StageStatus::Success
                 | StageStatus::PartialSuccess
+                | StageStatus::Fail
                 | StageStatus::Skipped => {
                     return Ok((outcome, attempt));
                 }
-                StageStatus::Fail | StageStatus::Retry => {
+                StageStatus::Retry => {
                     if attempt < policy.max_attempts {
                         let delay = policy.backoff.delay_for_attempt(attempt);
                         self.emitter.emit(&PipelineEvent::StageRetrying {
diff --git a/crates/attractor/src/validation/rules.rs b/crates/attractor/src/validation/rules.rs
index 971eb34fe..e45df775b 100644
--- a/crates/attractor/src/validation/rules.rs
+++ b/crates/attractor/src/validation/rules.rs
@@ -94,24 +94,12 @@ impl LintRule for TerminalNodeRule {
             return vec![Diagnostic {
                 rule: self.name().to_string(),
                 severity: Severity::Error,
-                message: "Pipeline must have exactly one terminal node (shape=Msquare or id exit/end)".to_string(),
+                message: "Pipeline must have at least one terminal node (shape=Msquare or id exit/end)".to_string(),
                 node_id: None,
                 edge: None,
                 fix: Some("Add a node with shape=Msquare or id 'exit'/'end'".to_string()),
             }];
         }
-        if terminal_count > 1 {
-            return vec![Diagnostic {
-                rule: self.name().to_string(),
-                severity: Severity::Error,
-                message: format!(
-                    "Pipeline must have exactly one terminal node, found {terminal_count}"
-                ),
-                node_id: None,
-                edge: None,
-                fix: Some("Remove extra terminal nodes so exactly one remains".to_string()),
-            }];
-        }
         Vec::new()
     }
 }