Refactoring

[alxwrd]

_format_fields seems clunky. The Javascript implementation in ratlog/ratlog.js seems a lot clearer

  const fieldString = Object.entries(fields || {})
    .map(([k, v]) => {
      const key = formatField(k)
      const value = formatField(v)
      return ` | ${key}${value && ': ' + value}`
    }).join('')

I also don't like the hacky newline escaping in escape. However,

newline = "\n"
print(repr("\\" + newline))
# '\\\n'

It's possible to string.replace("\n", "\\n"), but this just adds a special case for newlines. I don't know if this is better?

[jmsv]

ratlog.js defines a formatFields method that's called for key and value. Could we do something similar? e.g. (untested)

# Define this somewhere globally or within Log class
_format_field = lambda val: escape("|:", val) if val else ""

def create_field(entry):
    # Replace key & value string construction with _format_field call
    key = _format_field(entry[0])
    value = _format_field(entry[1])
    # Move colon from value definition to format string
    return " | {}: {}".format(key, value)

This might look tidier and aligns more to the reference implementation

[jmsv]

Regarding escaping: string.replace("\n", "\\n") seems like a bad idea imo. Fits the newline case but doesn't work with \t (tab) etc

[alxwrd]

Regarding escaping: string.replace("\n", "\n") seems like a bad idea imo. Fits the newline case but doesn't work with \t (tab) etc.

Agree. I just can't find a way to say:

>>> def escape(chars, string):
...     for char in chars:
...         string = string.replace(char, "\\"+char)
...     return string
...

>>> escape("\n", "this\ncontains\nnewlines")
'this\\\ncontains\\\nnewlines'
>>> print(_)
this\
contains\
newlines