Allow output from commands to be wrapped to terminal width (fix #81)

[devdanzin]

Adds --wrap to commands, so output that is too wide for a given terminal width is wrapped inside the table cells.

Uses shutil.get_terminal_size() to get terminal size, then calculates an approximation of maximum column width and passes that as maxcolwidths and maxheadercolwidths parameters to tabulate.tabulate().

Adds some tests, but not exact output testing.

Fixes #81, except for very narrow terminals with lots of metrics.

[codecov-commenter]

Codecov Report

Merging #201 (fd5511b) into master (b0411ae) will increase coverage by 0.09%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #201      +/-   ##
==========================================
+ Coverage   95.33%   95.42%   +0.09%     
==========================================
  Files          24       24              
  Lines        1244     1269      +25     
  Branches      279      287       +8     
==========================================
+ Hits         1186     1211      +25     
  Misses         33       33              
  Partials       25       25              

Files Changed	Coverage Δ
src/wily/__main__.py	95.69% <100.00%> (+0.11%)	⬆️
src/wily/commands/diff.py	89.28% <100.00%> (+0.12%)	⬆️
src/wily/commands/index.py	100.00% <100.00%> (ø)
src/wily/commands/list_metrics.py	90.90% <100.00%> (+2.02%)	⬆️
src/wily/commands/rank.py	96.61% <100.00%> (+0.05%)	⬆️
src/wily/commands/report.py	97.22% <100.00%> (+0.05%)	⬆️
src/wily/helper/__init__.py	100.00% <100.00%> (ø)

[tonybaloney]

Please can you comment with some screenshots of what this looks like to confirm I'm seeing the same thing

[devdanzin]

Thanks for taking a look at this!

First, I'll show some good cases for most commands, then I'll use wily report to show how it works in different widths and how and when it breaks.

Rank:

Diff:

Index:

List-metrics:

Report wide, default metrics:

Report very wide, default metrics:

Here we see that this PR isn't optimal about using available width: it doesn't actually need wrapping here.

Report very wide, many metrics:

How it sorta breaks:

When the terminal is narrow enough, table cells become vertical text one character wide. That might still be better than the otherwise overlapping output in some situation, but it does look silly.

How it breaks:

When the terminal is narrow enough, the code tries to output the vertical text as above, but fails and the result is harder to read than the previous overlapping output we'd get.

There's some more context at #81 (comment)

[tonybaloney]

Please change to default=True

[devdanzin]

Thanks for reviewing! Changed here and in all other commands, was that the intention?

[tonybaloney]

Great, in that case please change the PR so this new behaviour is on by default. This looks much better

[devdanzin]

Tests aren't passing due to an issue I see no relation with this PR, but could be wrong. It's fixed by #203, and I could make the fix in this PR instead if that's cleaner.