split: print "creating file" with --verbose in the -n modes

src/uu/split/src/split.rs

@@ -810,6 +810,9 @@ struct OutFile {
     filename: OsString,
     maybe_writer: Option<Writer>,
     is_new: bool,
+    /// Whether `--verbose` already reported this file, so that retries and
+    /// re-opens of the writer stay silent.
+    announced: bool,
 }
 
 /// A set of output files
@@ -853,6 +856,9 @@ impl ManageOutFiles for OutFiles {
             let maybe_writer = if is_writer_optional {
                 None
             } else {
+                if settings.verbose {
+                    print_creating_file(&filename)?;
+                }
                 let instantiated = settings.instantiate_current_writer(&filename, true);
                 // If there was an error instantiating the writer for a file,
                 // it could be due to hitting the system limit of open files,
@@ -873,12 +879,17 @@ impl ManageOutFiles for OutFiles {
                 filename,
                 maybe_writer,
                 is_new: true,
+                announced: !is_writer_optional,
             });
         }
         Ok(out_files)
     }
 
     fn instantiate_writer(&mut self, idx: usize, settings: &Settings) -> UResult<&mut Writer> {
+        if settings.verbose && !self[idx].announced {
+            print_creating_file(&self[idx].filename)?;
+            self[idx].announced = true;
+        }
         let mut count = 0;
         // Use-case for doing multiple tries of closing fds:
         // E.g. split running in parallel to other processes (e.g. another split) doing similar stuff,

tests/by-util/test_split.rs

@@ -2353,3 +2353,60 @@ fn test_obsolete_lines_not_read_after_double_dash() {
         .fails()
         .stderr_contains("cannot open '-1' for reading");
 }
+
+#[test]
+fn test_verbose_number_of_chunks() {
+    use std::fmt::Write as _;
+
+    for (args, input, created) in [
+        (&["-n", "2"][..], "a\nb\n", &["xaa", "xab"][..]),
+        (&["-n", "l/2"], "a\nb\n", &["xaa", "xab"]),
+        (&["-n", "r/2"], "a\nb\n", &["xaa", "xab"]),
+        (&["-n", "3"], "a\nb\n", &["xaa", "xab", "xac"]),
+        (&["-n", "l/3"], "a\nb\n", &["xaa", "xab", "xac"]),
+        (&["-n", "r/3"], "a\nb\n", &["xaa", "xab", "xac"]),
+        // Only the files that get created are announced with `-e`.
+        (&["-e", "-n", "5"], "a\nb\n", &["xaa", "xab", "xac", "xad"]),
+        (&["-e", "-n", "l/3"], "a\nb\n", &["xaa", "xab"]),
+        (&["-e", "-n", "r/3"], "a\nb\n", &["xaa", "xab"]),
+        // A file written to several times is still announced once.
+        (&["-n", "2"], "1\n2\n3\n4\n5\n", &["xaa", "xab"]),
+        (&["-n", "l/2"], "1\n2\n3\n4\n5\n", &["xaa", "xab"]),
+        (&["-n", "r/2"], "1\n2\n3\n4\n5\n", &["xaa", "xab"]),
+        (&["-e", "-n", "l/2"], "1\n2\n3\n4\n5\n", &["xaa", "xab"]),
+        (&["-e", "-n", "r/2"], "1\n2\n3\n4\n5\n", &["xaa", "xab"]),
+    ] {
+        let (at, mut ucmd) = at_and_ucmd!();
+        let expected = created.iter().fold(String::new(), |mut out, name| {
+            writeln!(out, "creating file '{name}'").unwrap();
+            out
+        });
+
+        ucmd.args(args)
+            .arg("--verbose")
+            .pipe_in(input)
+            .succeeds()
+            .stdout_only(expected);
+        for name in created {
+            assert!(at.file_exists(name), "{args:?}: {name} is missing");
+        }
+    }
+}
+
+#[test]
+fn test_verbose_kth_chunk_creates_no_file() {
+    for (args, chunk) in [
+        (&["-n", "1/2"][..], "abc"),
+        (&["-n", "l/1/2"], "abcd\n"),
+        (&["-n", "r/1/2"], "abcd\n"),
+    ] {
+        let (at, mut ucmd) = at_and_ucmd!();
+
+        ucmd.args(args)
+            .arg("--verbose")
+            .pipe_in("abcd\n")
+            .succeeds()
+            .stdout_only(chunk);
+        assert!(!at.file_exists("xaa"), "{args:?}: unexpected output file");
+    }
+}