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[PATCH v3 7/7] t/README: Add a note about the dangers of coverage chasing

From
Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date
Jul 25, 2010, 19:52 UTC
Message-ID
<1280087565-24671-8-git-send-email-avarab@gmail.com>
In-Reply-To
<1280087565-24671-1-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>
---

Jonathan doesn't particularly like this one. I have no particular preference, just trying to get across the point that you shouldn't cargo-cult-coverage.

 t/README |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)
diff --git a/t/README b/t/README
index 15d4b52..4fe8d50 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: Thomas Rast
Message 8 of 10 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. 2/7 Makefile: Include subdirectories in "make cover" reportsÆvar Arnfjörð Bjarmason, Jul 25, 2010
  4. 3/7 Makefile: Split out the untested functions targetÆvar Arnfjörð Bjarmason, Jul 25, 2010
  5. 4/7 Makefile: Add coverage-report-cover-db targetÆvar Arnfjörð Bjarmason, Jul 25, 2010
  6. 5/7 Makefile: Add coverage-report-cover-db-html targetÆvar Arnfjörð Bjarmason, Jul 25, 2010
  7. 6/7 t/README: A new section about test coverageÆvar Arnfjörð Bjarmason, Jul 25, 2010
  8. 7/7 t/README: Add a note about the dangers of coverage chasingÆvar Arnfjörð Bjarmason, Jul 25, 2010
  9. Thomas RastJul 26, 2010
  10. Ævar Arnfjörð BjarmasonJul 26, 2010

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