Call pytest_report_collectionfinish hook when --collect-only is passed

[nicoddemus]

Fix #2895

[asottile]

Just for my curiosity, what's the difference between option.collectonly and getoption("collect-only")?

[codecov]

Codecov Report

Merging #4725 into master will decrease coverage by 0.01%.
The diff coverage is 55.55%.

@@            Coverage Diff             @@
##           master    #4725      +/-   ##
==========================================
- Coverage   95.68%   95.66%   -0.02%     
==========================================
  Files         113      113              
  Lines       24963    24963              
  Branches     2478     2479       +1     
==========================================
- Hits        23886    23882       -4     
  Misses        762      762              
- Partials      315      319       +4

Flag	Coverage Δ
#docs	29.67% <0%> (+0.07%)	⬆️
#doctesting	29.67% <0%> (+0.07%)	⬆️
#linting	29.67% <0%> (+0.07%)	⬆️
#linux	95.5% <55.55%> (-0.01%)	⬇️
#nobyte	92.28% <55.55%> (-0.01%)	⬇️
#numpy	93.1% <55.55%> (-0.01%)	⬇️
#pexpect	42.11% <55.55%> (ø)	⬆️
#py27	93.69% <55.55%> (+0.01%)	⬆️
#py34	91.77% <55.55%> (+0.06%)	⬆️
#py35	91.77% <55.55%> (+0.06%)	⬆️
#py36	91.79% <55.55%> (+0.06%)	⬆️
#py37	93.8% <55.55%> (-0.01%)	⬇️
#trial	93.1% <55.55%> (-0.01%)	⬇️
#windows	93.86% <55.55%> (-0.01%)	⬇️
#xdist	93.71% <55.55%> (-0.01%)	⬇️

Impacted Files	Coverage Δ
testing/test_terminal.py	99.81% <100%> (ø)	⬆️
src/_pytest/terminal.py	91.73% <33.33%> (+0.15%)	⬆️
src/_pytest/cacheprovider.py	95.75% <0%> (-1.42%)	⬇️
src/_pytest/capture.py	93.66% <0%> (-0.46%)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update c780d1f...426d6e0. Read the comment docs.

[codecov]

Codecov Report

Merging #4725 into master will decrease coverage by 0.01%.
The diff coverage is 55.55%.

@@            Coverage Diff             @@
##           master    #4725      +/-   ##
==========================================
- Coverage   95.68%   95.66%   -0.02%     
==========================================
  Files         113      113              
  Lines       24963    24963              
  Branches     2478     2479       +1     
==========================================
- Hits        23886    23882       -4     
  Misses        762      762              
- Partials      315      319       +4

Flag	Coverage Δ
#docs	29.67% <0%> (+0.07%)	⬆️
#doctesting	29.67% <0%> (+0.07%)	⬆️
#linting	29.67% <0%> (+0.07%)	⬆️
#linux	95.5% <55.55%> (-0.01%)	⬇️
#nobyte	92.28% <55.55%> (-0.01%)	⬇️
#numpy	93.1% <55.55%> (-0.01%)	⬇️
#pexpect	42.11% <55.55%> (ø)	⬆️
#py27	93.69% <55.55%> (+0.01%)	⬆️
#py34	91.77% <55.55%> (+0.06%)	⬆️
#py35	91.77% <55.55%> (+0.06%)	⬆️
#py36	91.79% <55.55%> (+0.06%)	⬆️
#py37	93.8% <55.55%> (-0.01%)	⬇️
#trial	93.1% <55.55%> (-0.01%)	⬇️
#windows	93.86% <55.55%> (-0.01%)	⬇️
#xdist	93.71% <55.55%> (-0.01%)	⬇️

Impacted Files	Coverage Δ
testing/test_terminal.py	99.81% <100%> (ø)	⬆️
src/_pytest/terminal.py	91.73% <33.33%> (+0.15%)	⬆️
src/_pytest/cacheprovider.py	95.75% <0%> (-1.42%)	⬇️
src/_pytest/capture.py	93.66% <0%> (-0.46%)	⬇️

---

Continue to review full report at Codecov.

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Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update c780d1f...426d6e0. Read the comment docs.

[nicoddemus]

Just for my curiosity, what's the difference between option.collectonly and getoption("collect-only")?

None, except the former is not really recommended anymore, not sure what's the specific reason for it.