Fluent strings starting with '[' character get interpreted incorrectly about weblate

[henry-torproject]

This escaping is intentional in the translate-toolkit code, see https://github.com/translate/translate/blob/bf3b519010fd6c0f3cd53b210b5e1eb6be33bd8c/translate/storage/fluent.py#L55-L88.

If you feel this behavior should be changed, please open up an issue there.

@henry-torproject might be interested in this as well as an author of the referenced code.

Yes, it is indeed intentional.

The first thing to note is that { "[" } is a Fluent string literal, so

hud-init-stage-client-load-init-data = { "[" }{ -client }]: Loading

will produce exactly the same string as

hud-init-stage-client-load-init-data = [{ -client }]: Loading

so there should be no change in the end result.

The "[" at the start of a line is reserved in Fluent for selectors. E.g.

my-fluent-string = { $num ->
  [one] { $num } item
 *[other] { $num } items
 }

In your example, the original source is:

my-fluent-string = [ other

Since the "[" does not appear at the start of a line, it is technically valid. But the following are not:

my-fluent-string =
  [ other

my-fluent-string = first line
  [ second line

my-fluent-string =
  first line
  [ second line

On weblate, the user does not see the my-fluent-string line, and only sees everything after the "=" sign. You can think of the weblate input as everything that occurs after the "=" sign minus the indent. So

first line

second line

in the weblate input would become

my-fluent-string =
  first line
  second line

and simialrly

> [ other

would become

my-fluent-string =
  [ other

which is invalid Fluent.

Whilst we could have allowed for exceptions for the special case, it would have appeared inconsistent in the weblate context.

Besides the fact that [ gets replaced with { "[" } in Weblate, after you translate this problematic string, you receive the following error (but it still saves the translation):

Fluent translation syntax
Fluent syntax error: E0005: Expected message "hud-init-stage-client-load-init-data" to have a value or attributes [line 1, column 1].

This is because you need to escape the special "[" character, as in the original string. It would need to be

{ "[" }{ -client }]: Cargando

instead.

In this case, you may prefer to explicitly use

{ "[" }{ -client }{ "]" }: Loading

to make the string more symmetric, even though it is not necessary.

[nijel]

This escaping is intentional in the translate-toolkit code, see https://github.com/translate/translate/blob/bf3b519010fd6c0f3cd53b210b5e1eb6be33bd8c/translate/storage/fluent.py#L55-L88.

If you feel this behavior should be changed, please open up an issue there.

@henry-torproject might be interested in this as well as an author of the referenced code.

[github-actions]

The issue you've reported needs to be addressed in the translate-toolkit. Please file the issue there, and include links to any relevant specifications about the formats (if applicable).

[walpox]

Thank you for the clarification.