Add the -d / --stdout option. Fixes #164.

[akaihola]

• decide on the design (see this comment)
• only print out a single file
• unit tests
• change log

[levouh]

Useless nitpick @akaihola, going to pull/test and then I'll report back here. Otherwise LGTM.

[akaihola]

@levouh, I rebased on master after merging another branch.

[sourcery-ai]

Sourcery Code Quality Report

✅  Merging this PR will increase code quality in the affected files by 1.42%.

Quality metrics	Before	After	Change
Complexity	4.91 ⭐	4.93 ⭐	0.02 👎
Method Length	100.67 🙂	96.64 🙂	-4.03 👍
Working memory	9.23 🙂	9.13 🙂	-0.10 👍
Quality	62.93% 🙂	64.35% 🙂	1.42% 👍

Other metrics	Before	After	Change
Lines	1645	1841	196

Changed files	Quality Before	Quality After	Quality Change
src/darker/main.py	38.07% 😞	36.17% 😞	-1.90% 👎
src/darker/command_line.py	72.65% 🙂	71.87% 🙂	-0.78% 👎
src/darker/config.py	88.87% ⭐	91.51% ⭐	2.64% 👍
src/darker/help.py	76.50% ⭐	76.09% ⭐	-0.41% 👎
src/darker/tests/test_command_line.py	69.59% 🙂	69.00% 🙂	-0.59% 👎
src/darker/tests/test_config.py	65.90% 🙂	67.61% 🙂	1.71% 👍
src/darker/tests/test_main.py	67.74% 🙂	67.34% 🙂	-0.40% 👎

Here are some functions in these files that still need a tune-up:

File	Function	Complexity	Length	Working Memory	Quality	Recommendation
src/darker/main.py	format_edited_parts	22 😞	253 ⛔	19 ⛔	24.23% ⛔	Refactor to reduce nesting. Try splitting into smaller methods. Extract out complex expressions
src/darker/main.py	main	23 😞	305 ⛔	14 😞	26.50% 😞	Refactor to reduce nesting. Try splitting into smaller methods. Extract out complex expressions
src/darker/tests/test_main.py	test_main	2 ⭐	348 ⛔	18 ⛔	39.08% 😞	Try splitting into smaller methods. Extract out complex expressions
src/darker/tests/test_command_line.py	test_parse_command_line	4 ⭐	690 ⛔	9 🙂	47.89% 😞	Try splitting into smaller methods
src/darker/tests/test_config.py	test_load_config	0 ⭐	321 ⛔	12 😞	48.95% 😞	Try splitting into smaller methods. Extract out complex expressions

Legend and Explanation

The emojis denote the absolute quality of the code:

• ⭐ excellent
• 🙂 good
• 😞 poor
• ⛔ very poor

The 👍 and 👎 indicate whether the quality has improved or gotten worse with this pull request.

---

Please see our documentation here for details on how these metrics are calculated.

We are actively working on this report - lots more documentation and extra metrics to come!

Help us improve this quality report!