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[PATCH v2 7/7] t/README: Add a note about the dangers of coverage chasing

From
Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date
Jul 25, 2010, 14:41 UTC
Message-ID
<1280068861-17701-8-git-send-email-avarab@gmail.com>
In-Reply-To
<1280068861-17701-1-git-send-email-avarab@gmail.com>

Having no coverage at all is almost always a bad sign, but trying to attain 100% coverage everywhere is usually a waste of time. Add a paragraph to explain this to future test writers.

Inspired-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 t/README |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)
diff --git a/t/README b/t/README
index 2fa6744..400e2da 100644
--- a/t/README
+++ b/t/README
@@ -271,6 +271,15 @@ Do:
  - Check the test coverage for your tests. See the "Test coverage"
    below.
 
+   Don't blindly follow test coverage metrics, they're a good way to
+   spot if you've missed something. If a new function you added
+   doesn't have any coverage you're probably doing something wrong,
+   but having 100% coverage doesn't necessarily mean that you tested
+   everything.
+
+   Tests that are likely to smoke out future regressions are better
+   than tests that just inflate the coverage metrics.
+
 Don't:
 
  - exit() within a <script> part.
-- 
1.7.0.4
Previous: Ævar Arnfjörð BjarmasonNext: Jonathan Nieder
Message 12 of 17 in “Detailed test coverage reports for Git”
  1. 0/7 Detailed test coverage reports for GitÆvar Arnfjörð Bjarmason, Jul 25, 2010
  2. 1/7 gitignore: Ignore files generated by "make coverage"Ævar Arnfjörð Bjarmason, Jul 25, 2010
  3. Jonathan NiederJul 25, 2010
  4. 2/7 Makefile: Include subdirectories in "make cover" reportsÆvar Arnfjörð Bjarmason, Jul 25, 2010
  5. Jonathan NiederJul 25, 2010
  6. 3/7 Makefile: Split out the untested functions targetÆvar Arnfjörð Bjarmason, Jul 25, 2010
  7. 4/7 Makefile: Add coverage-report-cover-db targetÆvar Arnfjörð Bjarmason, Jul 25, 2010
  8. Jonathan NiederJul 25, 2010
  9. 5/7 Makefile: Add coverage-report-cover-db-html targetÆvar Arnfjörð Bjarmason, Jul 25, 2010
  10. Jonathan NiederJul 25, 2010
  11. 6/7 t/README: A new section about test coverageÆvar Arnfjörð Bjarmason, Jul 25, 2010
  12. 7/7 t/README: Add a note about the dangers of coverage chasingÆvar Arnfjörð Bjarmason, Jul 25, 2010
  13. Jonathan NiederJul 25, 2010
  14. Ævar Arnfjörð BjarmasonJul 25, 2010
  15. Jonathan NiederJul 25, 2010
  16. Ævar Arnfjörð BjarmasonJul 25, 2010
  17. Jonathan NiederJul 25, 2010

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