### Make sure you are using the *latest* version: run `youtube-dl --version` and ensure your version is *2018.12.31*. If it's not, read [this FAQ entry](https://github.com/rg3/youtube-dl/blob/master/README.md#how-do-i-update-youtube-dl) and update. Issues with outdated version will be rejected.
### Make sure you are using the *latest* version: run `youtube-dl --version` and ensure your version is *2019.01.02*. If it's not, read [this FAQ entry](https://github.com/rg3/youtube-dl/blob/master/README.md#how-do-i-update-youtube-dl) and update. Issues with outdated version will be rejected.
- [ ] I've **verified** and **I assure** that I'm running youtube-dl **2018.12.31**
- [ ] I've **verified** and **I assure** that I'm running youtube-dl **2019.01.02**
### Before submitting an *issue* make sure you have:
### Before submitting an *issue* make sure you have:
- [ ] At least skimmed through the [README](https://github.com/rg3/youtube-dl/blob/master/README.md), **most notably** the [FAQ](https://github.com/rg3/youtube-dl#faq) and [BUGS](https://github.com/rg3/youtube-dl#bugs) sections
- [ ] At least skimmed through the [README](https://github.com/rg3/youtube-dl/blob/master/README.md), **most notably** the [FAQ](https://github.com/rg3/youtube-dl#faq) and [BUGS](https://github.com/rg3/youtube-dl#bugs) sections
@ -36,7 +36,7 @@ Add the `-v` flag to **your command line** you run youtube-dl with (`youtube-dl
@ -261,11 +261,33 @@ title = meta.get('title') or self._og_search_title(webpage)
This code will try to extract from `meta` first and if it fails it will try extracting `og:title` from a `webpage`.
This code will try to extract from `meta` first and if it fails it will try extracting `og:title` from a `webpage`.
### Make regular expressions flexible
### Regular expressions
When using regular expressions try to write them fuzzy and flexible.
#### Don't capture groups you don't use
#### Example
Capturing group must be an indication that it's used somewhere in the code. Any group that is not used must be non capturing.
##### Example
Don't capture id attribute name here since you can't use it for anything anyway.
Correct:
```python
r'(?:id|ID)=(?P<id>\d+)'
```
Incorrect:
```python
r'(id|ID)=(?P<id>\d+)'
```
#### Make regular expressions relaxed and flexible
When using regular expressions try to write them fuzzy, relaxed and flexible, skipping insignificant parts that are more likely to change, allowing both single and double quotes for quoted values and so on.
##### Example
Say you need to extract `title` from the following HTML code:
Say you need to extract `title` from the following HTML code:
@ -298,6 +320,25 @@ title = self._search_regex(
webpage, 'title', group='title')
webpage, 'title', group='title')
```
```
### Long lines policy
There is a soft limit to keep lines of code under 80 characters long. This means it should be respected if possible and if it does not make readability and code maintenance worse.
For example, you should **never** split long string literals like URLs or some other often copied entities over multiple lines to fit this limit:
Wrap all extracted numeric data into safe functions from [`youtube_dl/utils.py`](https://github.com/rg3/youtube-dl/blob/master/youtube_dl/utils.py): `int_or_none`, `float_or_none`. Use them for string to number conversions as well.
Wrap all extracted numeric data into safe functions from [`youtube_dl/utils.py`](https://github.com/rg3/youtube-dl/blob/master/youtube_dl/utils.py): `int_or_none`, `float_or_none`. Use them for string to number conversions as well.