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I setup a configuration file with the following presets entries:
"petite pause (5 mn)": 300,
"grande pause (12 mn)": 720,
"séance travail (25 mn)": 1500
Notice the use of one accented character. The file is written in UTF-8 encoding. Now I restart gnome-shell. I see my presets, they are OK. I modify the duration in "Set Timer" to force a rewrite of the configuration file and now the configuration file is in ISO-8859-1 instead of UTF-8. I restart gnome-shell, the presets are no longer visible in the menu...
I can confirm this bug. The problem seem to be in the JSON.parse function. Because if you put the following lines after JSON.parse in line 353
global.log(jsondata["presets"]["presets"]["petite pause (5 mn)"]);
global.log(jsondata["presets"]["presets"]["grande pause (12 mn)"]);
global.log(jsondata["presets"]["presets"]["séance travail (25 mn)"]);
the output is as follows:
Of course both files (extension.js and gnome_shell_timer.json) being UTF-8 encoded.
Which is strange because RFC4627 says "JSON text SHALL be encoded in Unicode. The default encoding is UTF-8."
Won't be here for 1.5 weeks, so it won't happen 'til then.
I have filed Bug 658312 for the issue with GLib.file_set_contents.
Should be fixed now (using GSettings).