sort: make compression program failures non-fatal, warn and fallback to plain files

src/uu/sort/locales/en-US.ftl

@@ -15,7 +15,7 @@ sort-open-failed = open failed: {$path}: {$error}
 sort-parse-key-error = failed to parse key {$key}: {$msg}
 sort-cannot-read = cannot read: {$path}: {$error}
 sort-open-tmp-file-failed = failed to open temporary file: {$error}
-sort-compress-prog-execution-failed = couldn't execute compress program: errno {$code}
+sort-compress-prog-execution-failed = could not run compress program '{$prog}': {$error}
 sort-compress-prog-terminated-abnormally = {$prog} terminated abnormally
 sort-cannot-create-tmp-file = cannot create temporary file in '{$path}':
 sort-file-operands-combined = extra operand '{$file}'

src/uu/sort/locales/fr-FR.ftl

@@ -15,7 +15,7 @@ sort-open-failed = échec d'ouverture : {$path} : {$error}
 sort-parse-key-error = échec d'analyse de la clé {$key} : {$msg}
 sort-cannot-read = impossible de lire : {$path} : {$error}
 sort-open-tmp-file-failed = échec d'ouverture du fichier temporaire : {$error}
-sort-compress-prog-execution-failed = impossible d'exécuter le programme de compression : errno {$code}
+sort-compress-prog-execution-failed = impossible d'exécuter le programme de compression '{$prog}' : {$error}
 sort-compress-prog-terminated-abnormally = {$prog} s'est terminé anormalement
 sort-cannot-create-tmp-file = impossible de créer un fichier temporaire dans '{$path}' :
 sort-file-operands-combined = opérande supplémentaire '{$file}'

src/uu/sort/src/ext_sort.rs

@@ -20,7 +20,7 @@ use std::{
 };
 
 use itertools::Itertools;
-use uucore::error::UResult;
+use uucore::error::{UResult, strip_errno};
 
 use crate::Output;
 use crate::chunks::RecycledChunk;
@@ -52,10 +52,37 @@ pub fn ext_sort(
         let settings = settings.clone();
         move || sorter(&recycled_receiver, &sorted_sender, &settings)
     });
-    if settings.compress_prog.is_some() {
+
+    // Test if compression program exists and works, disable if not
+    let mut effective_settings = settings.clone();
+    if let Some(ref prog) = settings.compress_prog {
+        // Test the compression program by trying to spawn it
+        match std::process::Command::new(prog)
+            .stdin(std::process::Stdio::null())
+            .stdout(std::process::Stdio::null())
+            .stderr(std::process::Stdio::null())
+            .spawn()
+        {
+            Ok(mut child) => {
+                // Kill the test process immediately
+                let _ = child.kill();
+            }
+            Err(err) => {
+                // Print the error and disable compression
+                eprintln!(
+                    "sort: could not run compress program '{}': {}",
+                    prog,
+                    strip_errno(&err)
+                );
+                effective_settings.compress_prog = None;
+            }
+        }
+    }
+
+    if effective_settings.compress_prog.is_some() {
         reader_writer::<_, WriteableCompressedTmpFile>(
             files,
-            settings,
+            &effective_settings,
             &sorted_receiver,
             recycled_sender,
             output,
@@ -64,7 +91,7 @@ pub fn ext_sort(
     } else {
         reader_writer::<_, WriteablePlainTmpFile>(
             files,
-            settings,
+            &effective_settings,
             &sorted_receiver,
             recycled_sender,
             output,

src/uu/sort/src/merge.rs

@@ -488,7 +488,8 @@ impl WriteableTmpFile for WriteableCompressedTmpFile {
         let mut child = command
             .spawn()
             .map_err(|err| SortError::CompressProgExecutionFailed {
-                code: err.raw_os_error().unwrap(),
+                prog: compress_prog.to_owned(),
+                error: err,
             })?;
         let child_stdin = child.stdin.take().unwrap();
         Ok(Self {
@@ -522,7 +523,8 @@ impl ClosedTmpFile for ClosedCompressedTmpFile {
         let mut child = command
             .spawn()
             .map_err(|err| SortError::CompressProgExecutionFailed {
-                code: err.raw_os_error().unwrap(),
+                prog: self.compress_prog.clone(),
+                error: err,
             })?;
         let child_stdout = child.stdout.take().unwrap();
         Ok(CompressedTmpMergeInput {

src/uu/sort/src/sort.rs

@@ -152,8 +152,8 @@ pub enum SortError {
     #[error("{}", translate!("sort-open-tmp-file-failed", "error" => strip_errno(.error)))]
     OpenTmpFileFailed { error: std::io::Error },
 
-    #[error("{}", translate!("sort-compress-prog-execution-failed", "code" => .code))]
-    CompressProgExecutionFailed { code: i32 },
+    #[error("{}", translate!("sort-compress-prog-execution-failed", "prog" => .prog, "error" => strip_errno(.error)))]
+    CompressProgExecutionFailed { prog: String, error: std::io::Error },
 
     #[error("{}", translate!("sort-compress-prog-terminated-abnormally", "prog" => .prog.quote()))]
     CompressProgTerminatedAbnormally { prog: String },

tests/by-util/test_sort.rs

@@ -1002,8 +1002,7 @@ fn test_compress_merge() {
 #[test]
 #[cfg(not(target_os = "android"))]
 fn test_compress_fail() {
-    #[cfg(not(windows))]
-    new_ucmd!()
+    let result = new_ucmd!()
         .args(&[
             "ext_sort.txt",
             "-n",
@@ -1012,22 +1011,22 @@ fn test_compress_fail() {
             "-S",
             "10",
         ])
-        .fails()
-        .stderr_only("sort: couldn't execute compress program: errno 2\n");
-    // With coverage, it fails with a different error:
-    // "thread 'main' panicked at 'called `Option::unwrap()` on ...
-    // So, don't check the output
+        .succeeds();
+
+    #[cfg(not(windows))]
+    result.stderr_contains(
+        "sort: could not run compress program 'nonexistent-program': No such file or directory",
+    );
+
     #[cfg(windows)]
-    new_ucmd!()
-        .args(&[
-            "ext_sort.txt",
-            "-n",
-            "--compress-program",
-            "nonexistent-program",
-            "-S",
-            "10",
-        ])
-        .fails();
+    result.stderr_contains("could not run compress program");
+
+    // Check that it still produces correct sorted output to stdout
+    let expected = new_ucmd!()
+        .args(&["ext_sort.txt", "-n"])
+        .succeeds()
+        .stdout_move_str();
+    assert_eq!(result.stdout_str(), expected);
 }
 
 #[test]