From 2ba031677f991eb468a6b34bb1bf78e4fa908e13 Mon Sep 17 00:00:00 2001
From: Daniel Rainer <daniel.rainer@localhost>
Date: Wed, 25 Feb 2026 18:12:51 +0100
Subject: [PATCH] xtask: don't panic on failure

Panicking suggests that an assumption of our code was violated.
The current use of panics in xtasks is for expected failures, so it's
better to avoid panicking and instead just print the error message to
stderr and exit 1.

Closes #12482
---
 CHANGELOG.rst              |  4 ++++
 crates/xtask/src/format.rs |  6 +++---
 crates/xtask/src/lib.rs    | 17 ++++++++++++-----
 crates/xtask/src/main.rs   |  4 ++--
 4 files changed, 21 insertions(+), 10 deletions(-)

diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 6922892b4..03b6681bb 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -1,6 +1,10 @@
 fish ?.?.? (released ???)
 =========================
 
+For distributors and developers
+-------------------------------
+- xtasks no longer panic for expected failures
+
 Regression fixes:
 -----------------
 - (from 4.5.0) Intermediate ``⏎`` artifact when redrawing prompt (:issue:`12476`).
diff --git a/crates/xtask/src/format.rs b/crates/xtask/src/format.rs
index 33f232713..d21f61701 100644
--- a/crates/xtask/src/format.rs
+++ b/crates/xtask/src/format.rs
@@ -57,7 +57,7 @@ pub fn format(args: FormatArgs) {
                         "{YELLOW}warning: Did not find git, will proceed without checking for unstaged changes.{YELLOW:#}"
                     )
                 } else {
-                    panic!("Failed to run git status:\n{e}")
+                    fail!("Failed to run git status:\n{e}")
                 }
             }
         }
@@ -98,7 +98,7 @@ fn run_formatter(formatter: &mut Command, name: &str) {
     match formatter.status() {
         Ok(exit_status) => {
             if !exit_status.success() {
-                panic!("{name:?}: Files are not formatted correctly.");
+                fail!("{name:?}: Files are not formatted correctly.");
             }
         }
         Err(e) => {
@@ -107,7 +107,7 @@ fn run_formatter(formatter: &mut Command, name: &str) {
                     "{YELLOW}Formatter not found: {name:?}. Skipping associated files.{YELLOW:#}"
                 );
             } else {
-                panic!("Error occurred while running {name:?}:\n{e}")
+                fail!("Error occurred while running {name:?}:\n{e}")
             }
         }
     }
diff --git a/crates/xtask/src/lib.rs b/crates/xtask/src/lib.rs
index e2f23eb8a..c56ff4557 100644
--- a/crates/xtask/src/lib.rs
+++ b/crates/xtask/src/lib.rs
@@ -1,21 +1,28 @@
 use std::{ffi::OsStr, process::Command};
 
+macro_rules! fail {
+    ($($arg:tt)+) => {{
+        eprintln!($($arg)+);
+        std::process::exit(1);
+    }}
+}
+
 pub mod format;
 
 pub trait CommandExt {
-    fn run_or_panic(&mut self);
+    fn run_or_fail(&mut self);
 }
 
 impl CommandExt for Command {
-    fn run_or_panic(&mut self) {
+    fn run_or_fail(&mut self) {
         match self.status() {
             Ok(exit_status) => {
                 if !exit_status.success() {
-                    panic!("Command did not run successfully: {:?}", self.get_program())
+                    fail!("Command did not run successfully: {:?}", self.get_program())
                 }
             }
             Err(err) => {
-                panic!("Failed to run command: {err}");
+                fail!("Failed to run command: {err}")
             }
         }
     }
@@ -26,5 +33,5 @@ pub fn cargo<I, S>(cargo_args: I)
     I: IntoIterator<Item = S>,
     S: AsRef<OsStr>,
 {
-    Command::new(env!("CARGO")).args(cargo_args).run_or_panic();
+    Command::new(env!("CARGO")).args(cargo_args).run_or_fail();
 }
diff --git a/crates/xtask/src/main.rs b/crates/xtask/src/main.rs
index af405cd69..7744a682a 100644
--- a/crates/xtask/src/main.rs
+++ b/crates/xtask/src/main.rs
@@ -43,7 +43,7 @@ fn main() {
 fn run_checks() {
     let repo_root_dir = fish_build_helper::workspace_root();
     let check_script = repo_root_dir.join("build_tools").join("check.sh");
-    Command::new(check_script).run_or_panic();
+    Command::new(check_script).run_or_fail();
 }
 
 fn build_html_docs(fish_indent: Option<PathBuf>) {
@@ -94,5 +94,5 @@ fn build_html_docs(fish_indent: Option<PathBuf>) {
     Command::new(option_env!("FISH_SPHINX").unwrap_or("sphinx-build"))
         .env("PATH", new_path)
         .args(args)
-        .run_or_panic();
+        .run_or_fail();
 }