`mdbook-i18n-helpers@0.3.6` will be imcompatible with `mdbook@0.5.0`

[hwhsu1231]

Problem Description

Hello, mdbook-i18n-helpers Team,

I previously opened an issue reporting an error when using mdbook with mdbook-i18n-helpers:

• The v0.5.0-alpha.1 version of mdBook is incompatible with mdbook-i18n-helpers rust-lang/mdBook#2835

The error message is as follows:

thread 'main' panicked at crates/mdbook-core/src/config.rs:184:41:
unreachable: invalid key `output`
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

It seems that mdbook-i18n-helpers versions 0.3.6 and below are no longer compatible with the upcoming mdbook@0.5.0 due to its breaking changes. I was wondering if there are any plans for mdbook-i18n-helpers to support the upcoming mdbook@0.5.0 release?

Steps to Reproduce

Run the following commands to reproduce the issue on the master branch:

Click to expand the commands

# Prepare Environment
MDBOOK_VERSION=master
git clone --branch=${MDBOOK_VERSION} --depth=1 https://github.com/rust-lang/mdBook.git mdbook-${MDBOOK_VERSION}
cd mdbook-${MDBOOK_VERSION}
conda create --prefix ./.conda --yes
conda activate ./.conda
conda install conda-forge::rust --channel conda-forge --yes
export CARGO_INSTALL_ROOT=$(pwd)/.conda
cargo install --path . --locked
cargo install mdbook-i18n-helpers

# Build with mdbook-i18n-helpers
export MDBOOK_OUTPUT='{"xgettext": {"depth": 5}}'
mdbook build $(pwd)/guide --dest-dir $(pwd)/guide/locale/pot

The full log: log-build-docs-on-master-branch.txt

As a comparison, run the same commands with the v0.4.52 tag:

Click to expand the commands

# Prepare Environment
MDBOOK_VERSION=v0.4.52
git clone --branch=${MDBOOK_VERSION} --depth=1 https://github.com/rust-lang/mdBook.git mdbook-${MDBOOK_VERSION}
cd mdbook-${MDBOOK_VERSION}
conda create --prefix ./.conda --yes
conda activate ./.conda
conda install conda-forge::rust --channel conda-forge --yes
export CARGO_INSTALL_ROOT=$(pwd)/.conda
cargo install --path . --locked
cargo install mdbook-i18n-helpers

# Build with mdbook-i18n-helpers
export MDBOOK_OUTPUT='{"xgettext": {"depth": 5}}'
mdbook build $(pwd)/guide --dest-dir $(pwd)/guide/locale/pot

The full log: log-build-docs-on-v0.4.52-tag.txt

[mgeisler]

Hi @hwhsu1231, thanks a lot for the report! We will definitely want to make the extension compatible with the latest version of mdbook!

The links in rust-lang/mdBook#2835 to the commits is helpful: it seems like a lot has changed! We will need some time to digest this, but perhaps we can start by updating the extension to error out if it sees mdbook 0.5 or later.

A PR for that would be much appreciated!