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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"FontProperties fail to roundtrip from their str","articleBody":"\u003c!--To help us understand and resolve your issue, please fill out the form to the best of your ability.--\u003e\r\n\u003c!--You can feel free to delete the sections that do not apply.--\u003e\r\n\r\n### Bug report\r\n\r\n**Bug summary**\r\n\r\nFontProperties has a `__str__` that appears to be intended to allow roundtripping (see use of `get_fontconfig_pattern`/`parse_fontconfig_pattern`), but after `fp = FontProperties()`; one has `FontProperties(str(fp)) != fp`.\r\n\r\n**Code for reproduction**\r\n\r\n\u003c!--A minimum code snippet required to reproduce the bug.\r\nPlease make sure to minimize the number of dependencies required, and provide\r\nany necessary plotted data.\r\nAvoid using threads, as Matplotlib is (explicitly) not thread-safe.--\u003e\r\n\r\n```python\r\nfrom matplotlib.font_manager import FontProperties, findfont\r\nfrom matplotlib import style; style.use(\"seaborn\")\r\n\r\nfp = FontProperties()\r\nprint(fp)\r\nprint(findfont(fp))\r\nfp_str_roundtrip = FontProperties(str(fp))\r\nprint(fp_str_roundtrip)\r\nprint(findfont(fp_str_roundtrip))\r\n```\r\n(setting the style to (matplotlib's version of) seaborn has the side-effect of changing the default sans-serif font from dejavusans to arial, which leads to the difference in the result of findfont -- otherwise, the default sans-serif font is also dejavusans and both calls to findfont return it).\r\n\r\n**Actual outcome**\r\n\r\n\u003c!--The output produced by the above code, which may be a screenshot, console output, etc.--\u003e\r\n\r\n```\r\n:family=sans-serif:style=normal:variant=normal:weight=normal:stretch=normal:size=10.0\r\n/usr/share/fonts/TTF/arial.ttf\r\n:family=:style=normal:variant=normal:weight=normal:stretch=normal:size=10.0\r\nfindfont: Font family [''] not found. Falling back to DejaVu Sans.\r\n/home/antony/src/extern/matplotlib/lib/matplotlib/mpl-data/fonts/ttf/DejaVuSans.ttf\r\n```\r\n\r\n**Expected outcome**\r\n\r\nProper roundtripping.\r\n\r\n**Matplotlib version**\r\n\u003c!--Please specify your platform and versions of the relevant libraries you are using:--\u003e\r\n  * Operating system: linux\r\n  * Matplotlib version: master\r\n  * Matplotlib backend (`print(matplotlib.get_backend())`): any\r\n  * Python version: 37\r\n  * Jupyter version (if applicable):\r\n  * Other libraries: \r\n\r\n\u003c!--Please tell us how you installed matplotlib and python e.g., from source, pip, conda--\u003e\r\n\u003c!--If you installed from conda, please specify which channel you used if not the default--\u003e\r\n\r\n","author":{"url":"https://github.com/anntzer","@type":"Person","name":"anntzer"},"datePublished":"2019-08-04T21:23:43.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":3},"url":"https://github.com/14977/matplotlib/issues/14977"}