pr: Add support for -D/--date-format parameter

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

@@ -13,6 +13,8 @@ pr-help-pages = Begin and stop printing with page FIRST_PAGE[:LAST_PAGE]
 pr-help-header =
   Use the string header to replace the file name
                   in the header line.
+pr-help-date-format =
+  Use 'date'-style FORMAT for the header date.
 pr-help-double-space =
   Produce output that is double spaced. An extra <newline>
                   character is output following every <newline> found in the input.

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

@@ -13,6 +13,8 @@ pr-help-pages = Commencer et arrêter l'impression à la page PREMIÈRE_PAGE[:DE
 pr-help-header =
   Utiliser la chaîne d'en-tête pour remplacer le nom de fichier
                   dans la ligne d'en-tête.
+pr-help-date-format =
+  Utiliser le FORMAT de style 'date' pour la date dans la ligne d'en-tête.
 pr-help-double-space =
   Produire une sortie avec double espacement. Un caractère <saut de ligne>
                   supplémentaire est affiché après chaque <saut de ligne> trouvé dans l'entrée.

src/uu/pr/src/pr.rs

@@ -19,8 +19,8 @@ use thiserror::Error;
 use uucore::display::Quotable;
 use uucore::error::UResult;
 use uucore::format_usage;
-use uucore::translate;
 use uucore::time::{FormatSystemTimeFallback, format, format_system_time};
+use uucore::translate;
 
 const TAB: char = '\t';
 const LINES_PER_PAGE: usize = 66;
@@ -36,6 +36,7 @@ const FF: u8 = 0x0C_u8;
 
 mod options {
     pub const HEADER: &str = "header";
+    pub const DATE_FORMAT: &str = "date-format";
     pub const DOUBLE_SPACE: &str = "double-space";
     pub const NUMBER_LINES: &str = "number-lines";
     pub const FIRST_LINE_NUMBER: &str = "first-line-number";
@@ -176,6 +177,13 @@ pub fn uu_app() -> Command {
                 .help(translate!("pr-help-header"))
                 .value_name("STRING"),
         )
+        .arg(
+            Arg::new(options::DATE_FORMAT)
+                .short('D')
+                .long(options::DATE_FORMAT)
+                .value_name("FORMAT")
+                .help(translate!("pr-help-date-format")),
+        )
         .arg(
             Arg::new(options::DOUBLE_SPACE)
                 .short('d')
@@ -401,16 +409,21 @@ fn parse_usize(matches: &ArgMatches, opt: &str) -> Option<Result<usize, PrError>
         .map(from_parse_error_to_pr_error)
 }
 
-fn get_date_format() -> String {
-    // Replicate behavior from GNU manual.
-    if std::env::var("POSIXLY_CORRECT").is_ok()
-        // TODO: This needs to be moved to uucore and handled by icu?
-        && (std::env::var("LC_TIME").unwrap_or_default() == "POSIX"
-            || std::env::var("LC_ALL").unwrap_or_default() == "POSIX")
-    {
-        "%b %e %H:%M %Y"
-    } else {
-        format::LONG_ISO
+fn get_date_format(matches: &ArgMatches) -> String {
+    match matches.get_one::<String>(options::DATE_FORMAT) {
+        Some(format) => format,
+        None => {
+            // Replicate behavior from GNU manual.
+            if std::env::var("POSIXLY_CORRECT").is_ok()
+                // TODO: This needs to be moved to uucore and handled by icu?
+                && (std::env::var("LC_TIME").unwrap_or_default() == "POSIX"
+                    || std::env::var("LC_ALL").unwrap_or_default() == "POSIX")
+            {
+                "%b %e %H:%M %Y"
+            } else {
+                format::LONG_ISO
+            }
+        }
     }
     .to_string()
 }
@@ -514,7 +527,7 @@ fn build_options(
             format_system_time(
                 &mut v,
                 time,
-                &get_date_format(),
+                &get_date_format(matches),
                 FormatSystemTimeFallback::Integer,
             )
             .ok()

tests/by-util/test_pr.rs

@@ -404,6 +404,50 @@ fn test_with_offset_space_option() {
 
 #[test]
 fn test_with_date_format() {
+    let test_file_path = "test_one_page.log";
+    let expected_test_file_path = "test_one_page.log.expected";
+    let mut scenario = new_ucmd!();
+    let value = file_last_modified_time_format(&scenario, test_file_path, "%Y__%s");
+    scenario
+        .args(&[test_file_path, "-D", "%Y__%s"])
+        .succeeds()
+        .stdout_is_templated_fixture(expected_test_file_path, &[("{last_modified_time}", &value)]);
+
+    // "Format" doesn't need to contain any replaceable token.
+    let mut scenario = new_ucmd!();
+    scenario
+        .args(&[test_file_path, "-D", "Hello!"])
+        .succeeds()
+        .stdout_is_templated_fixture(
+            expected_test_file_path,
+            &[("{last_modified_time}", "Hello!")],
+        );
+
+    // Long option also works
+    let mut scenario = new_ucmd!();
+    scenario
+        .args(&[test_file_path, "--date-format=Hello!"])
+        .succeeds()
+        .stdout_is_templated_fixture(
+            expected_test_file_path,
+            &[("{last_modified_time}", "Hello!")],
+        );
+
+    // Option takes precedence over environment variables
+    let mut scenario = new_ucmd!();
+    scenario
+        .env("POSIXLY_CORRECT", "1")
+        .env("LC_TIME", "POSIX")
+        .args(&[test_file_path, "-D", "Hello!"])
+        .succeeds()
+        .stdout_is_templated_fixture(
+            expected_test_file_path,
+            &[("{last_modified_time}", "Hello!")],
+        );
+}
+
+#[test]
+fn test_with_date_format_env() {
     const POSIXLY_FORMAT: &str = "%b %e %H:%M %Y";
 
     // POSIXLY_CORRECT + LC_ALL/TIME=POSIX uses "%b %e %H:%M %Y" date format