PHP extractor misses plural strings that use brackets in their discriminator

[NielsdeBlaauw]

Bug Report

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• Yes, more specifically, I reviewed the guidelines on how to write clear bug reports.

Describe the current, buggy behavior
When running make-pot the i18n commando can not correctly extract plurals when there brackets in the discriminator.

This is much like #225, but for PHP.

The reproduction example below is a minimal reproduction. The original case for us was code generated by Twig, which looks like

echo sprintf(_n("Reading time: %s minute", "Reading time: %s minutes", ($context['x'] ?? null), "demo"), ($context['x'] ?? null));

Describe how other contributors can replicate this bug

1. Create a php file with the following two string:

echo sprintf(_n("Reading time: %s minute", "Reading time: %s minutes", (1), "demo"), 1);
echo sprintf(_n("Download time: %s minute", "Download time: %s minutes", 1, "demo"), 1));

2. run wp i18n make-pot
3. Check resulting pot file. Download time is available to translate. Reading time is not.

Describe what you would expect as the correct outcome
The resulting pot file should contain both Reading time and Download Time.

[swissspidy]

This is a known bug in the underlying gettext library we're using for extracting the function calls: php-gettext/Gettext#229

It might not a bug in v5, but we're still on v4 due to PHP version requirements.

[swissspidy]

It might be possible to fix this upstream in v4, but needs someone to write a PR.

[swissspidy]

Since this is blocked by the upstream library and an easy workaround exists, I am closing this one for now