Equalizing samples when comparing middle revision against good and bad.

scripts/slave/recipe_modules/auto_bisect/revision_state.py

Index: scripts/slave/recipe_modules/auto_bisect/revision_state.py
diff --git a/scripts/slave/recipe_modules/auto_bisect/revision_state.py b/scripts/slave/recipe_modules/auto_bisect/revision_state.py
index 9ba13ff30eb7fd4bb99b3b7ffefb374a6746c946..ed80ac1b5b097e7524000c4610d3f5102066baf2 100644
--- a/scripts/slave/recipe_modules/auto_bisect/revision_state.py
+++ b/scripts/slave/recipe_modules/auto_bisect/revision_state.py
@@ -544,10 +544,12 @@ class RevisionState(object):
       return self.overall_return_code == self.bisector.lkgr.overall_return_code
 
     while True:
+      truncate_length = min(len(x) for x in (self.bisector.lkgr.values,
+                                             self.bisector.fkbr.values))

[dtu, 2016/04/20 23:01:17]

A little bit weird for taking the min of just two values. Why not just
min(len(lkgr), len(fkbr))?

(In fact, you don't even need to take the min. Your previous strategy of doing
lkgr[:len(fkbr)] and fkbr[:len(lkgr)] works as well.)

(I also notice that this class is reaching into self.bisector a lot, and that's
the code smell "feature envy.")

[RobertoCN, 2016/04/20 23:13:33]

done. 

Agreed. revision_state will be gutted soon.

       diff_from_good = self.bisector.significantly_different(
-          self.bisector.lkgr.values, self.values)
+          self.bisector.lkgr.values[:truncate_length], self.values)
       diff_from_bad = self.bisector.significantly_different(
-          self.bisector.fkbr.values, self.values)
+          self.bisector.fkbr.values[:truncate_length], self.values)
 
       if diff_from_good and diff_from_bad:
         # Multiple regressions.