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Issue with default_style and lines that include \n
Hi, I am facing an issue with strings which include newline characters getting formatted poorly. Here is an example that hopefully illustrates what I am looking for:
test = {}
test['test'] = 'This is a really long line that will get split into multiple lines when using folded style. With literal style, it will stay a single line'
t = yaml.dump(test, default_style='|')
print(t)
t = yaml.dump(test, default_style='>')
print(t)
test['test'] = 'This is a really long line that will get split \ninto multiple lines when using folded style. With literal style, it will stay a single line'
t = yaml.dump(test, default_style='|')
print(t)
t = yaml.dump(test, default_style='>')
print(t)
produces
"test": |-
This is a really long line that will get split into multiple lines when using folded style. With literal style, it will stay a single line
"test": >-
This is a really long line that will get split into multiple lines when using folded
style. With literal style, it will stay a single line
"test": "This is a really long line that will get split \ninto multiple lines when\
\ using folded style. With literal style, it will stay a single line"
"test": "This is a really long line that will get split \ninto multiple lines when\
\ using folded style. With literal style, it will stay a single line"
What I want from the second one is:
"test": |-
This is a really long line that will get split
into multiple lines when using folded style. With literal style, it will stay a single line
Sorry if I mixed up the terminology in my example!
It looks like if I double escape the \n
, it at least preserves the style format, although ignores the newline completely:
test['test'] = 'This is a really long line that will get split \\ninto multiple lines when using folded style. With literal style, it will stay a single line'
t = yaml.dump(test, default_style='|')
print(t)
t = yaml.dump(test, default_style='>')
print(t)
Result:
"test": |-
This is a really long line that will get split \ninto multiple lines when using folded style. With literal style, it will stay a single line
"test": >-
This is a really long line that will get split \ninto multiple lines when using
folded style. With literal style, it will stay a single line
You need to strip the space before the newline. I believe this is the code in the Emitter that is responsible for this.
This can be done by adding.
In [1]: import yaml
...:
...: def yaml_multiline_string_presenter(dumper, data):
...: if len(data.splitlines()) > 1:
...: data = '\n'.join([line.rstrip() for line in data.strip().splitlines()])
...: return dumper.represent_scalar('tag:yaml.org,2002:str', data, style='|')
...: return dumper.represent_scalar('tag:yaml.org,2002:str', data)
...: yaml.add_representer(str, yaml_multiline_string_presenter)
In [2]: test = {}
...: test['test'] = 'This is a really long line that will get split into multiple lines when using folded style. With literal style, it will stay a single line'
...: t = yaml.dump(test, default_style='|')
...: print(t)
...: t = yaml.dump(test, default_style='>')
...: print(t)
...:
...: test['test'] = 'This is a really long line that will get split \ninto multiple lines when using folded style. With literal style, it will stay a single line'
...: t = yaml.dump(test, default_style='|')
...: print(t)
...: t = yaml.dump(test, default_style='>')
...: print(t)
Results
"test": |-
This is a really long line that will get split into multiple lines when using folded style. With literal style, it will stay a single line
"test": >-
This is a really long line that will get split into multiple lines when using folded
style. With literal style, it will stay a single line
"test": |-
This is a really long line that will get split
into multiple lines when using folded style. With literal style, it will stay a single line
"test": |-
This is a really long line that will get split
into multiple lines when using folded style. With literal style, it will stay a single line