This is done in preparation for Fluent's FTL files, which will be placed
in `localization/fluent/`. Having a shared parent reduces top-level
clutter in the repo and makes it easier to find the localization files
for translators, including realizing that both PO and FTL files exist.
We keep PO and FTL files in separate directories because we need to
rebuild on any changes in the PO directory (technically only when there
are changes to `*.po` files, but due to technical limitations we can't
reliably trigger rebuilds only if those changes but not other files in
the same directory.) Changes to FTL files do not require rebuilds for
dev builds, since for these `rust-embed` does not actually embed them
into the binary but rather loads them from the file system at runtime.
Closes#12193
Also merge them into one warning because some of these lines wrap
on a small (80 column) terminal, which looks weird. The reason they
wrap might be the long prefix ("warning: fish-build-man-pages@0.0.0:").
Their msgfmt doesn't support --output-file=- yet, so use a temporary
file if "msgfmt" doesn't support "--check-format". Else we should
have GNU gettext which supports both.
See #11982
This command is only used to determine availability of `msgfmt`. Without
these changes, the entire help output shows up if the code panics later
on, which adds useless bloat to the output, making it harder to analyze
what went wrong.
Closes#11848
Prior to this, when `msgfmt` failed, this would be detected indirectly
by the parser, which would then panic due to it input being empty.
Explicit checking allows us to properly display `msgfmt`'s error
message.
Closes#11847
This completely removes our runtime dependency on gettext. As a
replacement, we have our own code for runtime localization in
`src/wutil/gettext.rs`. It considers the relevant locale variables to
decide which message catalogs to take localizations from. The use of
locale variables is mostly the same as in gettext, with the notable
exception that we do not support "default dialects". If `LANGUAGE=ll` is
set and we don't have a `ll` catalog but a `ll_CC` catalog, we will use
the catalog with the country code suffix. If multiple such catalogs
exist, we use an arbitrary one. (At the moment we have at most one
catalog per language, so this is not particularly relevant.)
By using an `EnvStack` to pass variables to gettext at runtime, we now
respect locale variables which are not exported.
For early output, we don't have an `EnvStack` to pass, so we add an
initialization function which constructs an `EnvStack` containing the
relevant locale variables from the corresponding Environment variables.
Treat `LANGUAGE` as path variable. This add automatic colon-splitting.
The sourcing of catalogs is completely reworked. Instead of looking for
MO files at runtime, we create catalogs as Rust maps at build time, by
converting PO files into MO data, which is not stored, but immediately
parsed to extract the mappings. From the mappings, we create Rust source
code as a build artifact, which is then macro-included in the crate's
library, i.e. `crates/gettext-maps/src/lib.rs`. The code in
`src/wutil/gettext.rs` includes the message catalogs from this library,
resulting in the message catalogs being built into the executable.
The `localize-messages` feature can now be used to control whether to
build with gettext support. By default, it is enabled. If `msgfmt` is
not available at build time, and `gettext` is enabled, a warning will be
emitted and fish is built with gettext support, but without any message
catalogs, so localization will not work then.
As a performance optimization, for each language we cache a separate
Rust source file containing its catalog as a map. This allows us to
reuse parsing results if the corresponding PO files have not changed
since we cached the parsing result.
Note that this approach does not eliminate our build-time dependency on
gettext. The process for generating PO files (which uses `msguniq` and
`msgmerge`) is unchanged, and we still need `msgfmt` to translate from
PO to MO. We could parse PO files directly, but these are significantly
more complex to parse, so we use `msgfmt` to do it for us and parse the
resulting MO data.
Advantages of the new approach:
- We have no runtime dependency on gettext anymore.
- The implementation has the same behavior everywhere.
- Our implementation is significantly simpler than GNU gettext.
- We can have localization in cargo-only builds by embedding
localizations into the code.
Previously, localization in such builds could only work reliably as
long as the binary was not moved from the build directory.
- We no longer have to take care of building and installing MO files in
build systems; everything we need for localization to work happens
automatically when building fish.
- Reduced overhead when disabling localization, both in compilation time
and binary size.
Disadvantages of this approach:
- Our own runtime implementation of gettext needs to be maintained.
- The implementation has a more limited feature set (but I don't think
it lacks any features which have been in use by fish).
Part of #11726Closes#11583Closes#11725Closes#11683
