Often companies who are new to TDD ask us, what should we measure to know if we are headed in the right direction with regards to TDD. Here are some things you might consider. My take is, less is more. Don't measure 100 things, focus on a few at a time and move on.

1. Good Metrics for a
TDD Program
“Less is More”
Naresh Jain
naresh@industriallogic.com
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2. C3 - TreeMap
• Coverage
• Complexity
• Churn
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3. Test vs. Production Code
Src LOC Test LOC
60,000
45,000
30,000
15,000
0
15 Feb 2 Mar 17 Mar 1 Apr 18 Apr 1 May 16 May 31 May 15 Jun 30 Jun
Usually Test Driven code has more Test Code than Production Code
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4. Test Run Trend with
every CI Build
# of Failing Test # of Passing
300
225
150
75
0
B1 B2 B3 B4 B5 B6 B7 B8
Each Build
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5. Test Balance
• # of commits that include Tests over time (weekly)
Commits With Tests Commits Without Tests
150.0
112.5
75.0
37.5
0
W1 W2 W3 W4 W5 W6 W7
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6. Test Churn
• # of tests added/removed over time (weekly)
Tests Added Tests Removed
60
45
30
15
0
W1 W2 W3 W4 W5 W6
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7. Satisfaction Rating from
Developers and Testers
Devs Testers
70.0
52.5
%
35.0
17.5
0
June 6th June 13th June 20th June 27th July 4th July 11th July 18th
Weekly
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8. Thank You!
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