From 2ffe30ecf0bf12ddc7cf89e30445a5a9ac67df89 Mon Sep 17 00:00:00 2001
From: Sophia June Turner <547158+sophiajt@users.noreply.github.com>
Date: Tue, 5 Dec 2023 19:42:55 +1300
Subject: [PATCH] Respect non-zero exit code in subexpressions and blocks
 (#8984)

# Description

This PR changes the way we handled non-zero exit codes to be and early
exit between `foo; bar`. If `foo` in the example has a non-zero exit
code, `bar` wouldn't be run.

This also affects subexpressions.
---
 crates/nu-engine/src/eval.rs | 32 ++++++++------------------------
 1 file changed, 8 insertions(+), 24 deletions(-)

diff --git a/crates/nu-engine/src/eval.rs b/crates/nu-engine/src/eval.rs
index 307a08eb73..075b7388e8 100644
--- a/crates/nu-engine/src/eval.rs
+++ b/crates/nu-engine/src/eval.rs
@@ -723,7 +723,13 @@ pub fn eval_block(
                         let mut v: Vec<_> = exit_code.collect();
 
                         if let Some(v) = v.pop() {
+                            let break_loop = !matches!(v.as_i64(), Ok(0));
+
                             stack.add_env_var("LAST_EXIT_CODE".into(), v);
+                            if break_loop {
+                                input = PipelineData::empty();
+                                break;
+                            }
                         }
                     }
                 }
@@ -741,31 +747,9 @@ pub fn eval_subexpression(
     engine_state: &EngineState,
     stack: &mut Stack,
     block: &Block,
-    mut input: PipelineData,
+    input: PipelineData,
 ) -> Result<PipelineData, ShellError> {
-    for pipeline in block.pipelines.iter() {
-        let mut stderr_writer_jobs = vec![];
-        for expr in pipeline.elements.iter() {
-            input = eval_element_with_input(
-                engine_state,
-                stack,
-                expr,
-                input,
-                true,
-                false,
-                &mut stderr_writer_jobs,
-            )?
-            .0
-        }
-        // `eval_element_with_input` may creates some threads
-        // to write stderr message to a file, here we need to wait and make sure that it's
-        // finished.
-        for h in stderr_writer_jobs {
-            let _ = h.join();
-        }
-    }
-
-    Ok(input)
+    eval_block(engine_state, stack, block, input, true, false)
 }
 
 pub fn eval_variable(