rage: Add localized manpages to the Debian package

rage/CHANGELOG.md

@@ -13,6 +13,7 @@ to 1.0.0 are beta releases.
 - `rage-keygen -y IDENTITY_FILE` to convert identity files to recipients.
 - Elvish completions to the Debian package. These are not automatically
   discovered; Elvish users will need to manually import them.
+- Localized manpages to the Debian package.
 
 ### Changed
 - MSRV is now 1.65.0.

rage/Cargo.toml

@@ -79,7 +79,7 @@ assets = [
 
     # From the default `/etc/manpath.config` created by the `man-db` package:
     # > MANPATH_MAP     /usr/bin                /usr/share/man
-    ["target/release/manpages/rage*.1.gz", "usr/share/man/man1/", "644"],
+    ["target/release/manpages/**/rage*.1.gz", "usr/share/man/", "644"],
 
     ["../README.md", "usr/share/doc/rage/README.md", "644"],
 ]
@@ -125,7 +125,7 @@ clap = { workspace = true, features = ["string", "unstable-styles"] }
 clap_complete = "4"
 clap_mangen = "0.2"
 flate2 = "1"
-i18n-embed = { workspace = true, features = ["desktop-requester"] }
+i18n-embed.workspace = true
 i18n-embed-fl.workspace = true
 lazy_static.workspace = true
 rust-embed.workspace = true

rage/build.rs

@@ -11,6 +11,7 @@ use clap_mangen::{
     Man,
 };
 use flate2::{write::GzEncoder, Compression};
+use i18n_embed::unic_langid::LanguageIdentifier;
 
 mod i18n {
     include!("src/bin/rage/i18n.rs");
@@ -243,8 +244,6 @@ impl Cli {
 }
 
 fn main() -> io::Result<()> {
-    i18n::load_languages();
-
     // `OUT_DIR` is "intentionally opaque as it is only intended for `rustc` interaction"
     // (https://github.com/rust-lang/cargo/issues/9858). Peek into the black box and use
     // it to figure out where the target directory is.
@@ -257,9 +256,38 @@ fn main() -> io::Result<()> {
             .to_path_buf(),
     };
 
-    let mut cli = Cli::build();
-    cli.generate_completions(&out_dir.join("completions"))?;
-    cli.generate_manpages(&out_dir.join("manpages"))?;
+    // Generate the completions in English, because these aren't easily localizable.
+    i18n::load_languages(&[]);
+    Cli::build().generate_completions(&out_dir.join("completions"))?;
+
+    // Generate manpages for all supported languages.
+    let manpage_dir = out_dir.join("manpages");
+    for lang_dir in fs::read_dir("./i18n")? {
+        let lang_dir = lang_dir?.file_name();
+        let lang: LanguageIdentifier = lang_dir
+            .to_str()
+            .expect("should be valid Unicode")
+            .parse()
+            .expect("should be valid language identifier");
+
+        // Render the manpages into the correct folder structure, so that local checks can
+        // be performed with `man -M target/debug/manpages BINARY_NAME`.
+        let mut out_dir = if lang.language.as_str() == "en" {
+            manpage_dir.clone()
+        } else {
+            let mut lang_str = lang.language.as_str().to_owned();
+            if let Some(region) = lang.region {
+                // Locales for manpages use the POSIX format with underscores.
+                lang_str += "_";
+                lang_str += region.as_str();
+            }
+            manpage_dir.join(lang_str)
+        };
+        out_dir.push("man1");
+
+        i18n::load_languages(&[lang]);
+        Cli::build().generate_manpages(&out_dir)?;
+    }
 
     Ok(())
 }

rage/src/bin/rage-keygen/main.rs

@@ -2,6 +2,7 @@
 
 use age::{cli_common::file_io, secrecy::ExposeSecret};
 use clap::Parser;
+use i18n_embed::DesktopLanguageRequester;
 
 use std::io::{self, Write};
 
@@ -30,8 +31,9 @@ fn main() -> Result<(), error::Error> {
         .parse_default_env()
         .init();
 
-    let requested_languages = i18n::load_languages();
-    age::localizer().select(&requested_languages).unwrap();
+    let supported_languages =
+        i18n::load_languages(&DesktopLanguageRequester::requested_languages());
+    age::localizer().select(&supported_languages).unwrap();
 
     let opts = cli::AgeOptions::parse();
 

rage/src/bin/rage-mount/main.rs

@@ -8,6 +8,7 @@ use age::{
 use clap::{CommandFactory, Parser};
 use fuse_mt::FilesystemMT;
 use fuser::MountOption;
+use i18n_embed::DesktopLanguageRequester;
 use log::info;
 
 use std::fmt;
@@ -176,8 +177,9 @@ fn main() -> Result<(), Error> {
         .parse_default_env()
         .init();
 
-    let requested_languages = i18n::load_languages();
-    age::localizer().select(&requested_languages).unwrap();
+    let supported_languages =
+        i18n::load_languages(&DesktopLanguageRequester::requested_languages());
+    age::localizer().select(&supported_languages).unwrap();
 
     if console::user_attended() && args().len() == 1 {
         cli::AgeMountOptions::command().print_help()?;

rage/src/bin/rage/i18n.rs

@@ -1,7 +1,6 @@
 use i18n_embed::{
     fluent::{fluent_language_loader, FluentLanguageLoader},
     unic_langid::LanguageIdentifier,
-    DesktopLanguageRequester,
 };
 use lazy_static::lazy_static;
 use rust_embed::RustEmbed;
@@ -14,11 +13,19 @@ lazy_static! {
     pub(crate) static ref LANGUAGE_LOADER: FluentLanguageLoader = fluent_language_loader!();
 }
 
-pub(crate) fn load_languages() -> Vec<LanguageIdentifier> {
-    let requested_languages = DesktopLanguageRequester::requested_languages();
-    i18n_embed::select(&*LANGUAGE_LOADER, &Localizations, &requested_languages).unwrap();
+/// Selects the most suitable available language in order of preference by
+/// `requested_languages`, and loads it using the `rage` [`LANGUAGE_LOADER`] from the
+/// languages available in `rage/i18n/`.
+///
+/// Returns the available languages that were negotiated as being the most suitable to be
+/// selected, and were loaded by [`i18n_embed::select`].
+pub(crate) fn load_languages(
+    requested_languages: &[LanguageIdentifier],
+) -> Vec<LanguageIdentifier> {
+    let supported_languages =
+        i18n_embed::select(&*LANGUAGE_LOADER, &Localizations, &requested_languages).unwrap();
     // Unfortunately the common Windows terminals don't support Unicode Directionality
     // Isolation Marks, so we disable them for now.
     LANGUAGE_LOADER.set_use_isolating(false);
-    requested_languages
+    supported_languages
 }

rage/src/bin/rage/main.rs

@@ -10,6 +10,7 @@ use age::{
     Identity, IdentityFile, IdentityFileEntry, Recipient,
 };
 use clap::{CommandFactory, Parser};
+use i18n_embed::DesktopLanguageRequester;
 
 use std::fs::File;
 use std::io::{self, BufRead, BufReader};
@@ -521,8 +522,9 @@ fn main() -> Result<(), error::Error> {
         .parse_default_env()
         .init();
 
-    let requested_languages = i18n::load_languages();
-    age::localizer().select(&requested_languages).unwrap();
+    let supported_languages =
+        i18n::load_languages(&DesktopLanguageRequester::requested_languages());
+    age::localizer().select(&supported_languages).unwrap();
 
     // If you are piping input with no other args, this will not allow
     // it.