Support for all line colouring

[SixFive7]

What issue does this PR address?
#35

Does this PR introduce a breaking change?
Not expected. But please check.

Please check if the PR fulfills these requirements

• The commit follows our guidelines
• Unit Tests for the changes have been added (for bug fixes / features)
  Just changes. No extra tests.

Other information:
An example of a possible (if not somewhat ugly) output:

I'm unsure of line 26 in ThemedValueFormatterState.cs.

Also, there might be a cleaner way to keep the Events.LogEventLevel.Information statements out of the tests?

Finally I only implemented SystemConsoleThemes.Literate as an example as I have no clue what colouring defaults are appropriate.

[nblumhardt]

Thanks!

I think all of the threading of the level through the various pieces is solid. I don't think we need to bake the idea of a "line style" into ConsoleTheme directly, though: if we overload Set() to optionally accept a level, then subclass themes could opt in to level-specific line colouring.

E.g. if, in ConsoleTheme we have:

public abstract int Set(TextWriter output, ConsoleThemeStyle style);

public virtual int Set(TextWriter output, ConsoleThemeStyle style, LogEventLevel level)
{
    return Set(output, style);
}

This also avoids changing the signature of the public Set method, since it'd be a breaking change for subclasses.

(It might be one step too far, but with some tricky substitution, we could introduce a new Level member to ConsoleThemeStyle, and only trigger using the level-specific LevelDebug etc. members when falling back to the two-argument Set method.)

Here's what the old theme looked like, just for historical interest :-)

[jwillmer]

When can we expect a merge?

[kyrylomyr]

It would be great to see this PR live

[nblumhardt]

Closing this one as stale, but if the OP or anyone following along is keen to follow up - I left some comments originally above; I think in order to merge this we'd also need at least one usable/aesthetically-pleasing example we could point folks to.

[Hedgineering]

Somewhat similar issue but I was trying to color the full line based on log levels;

I figured out how to do it. You can find how I accomplished it here if you're interested:
#35 (comment)