[LNT] r240423 - Don't crash when aggregation of samples results in 0 value in ComparisonResult constructor.

[Kristof Beyls]

Author: kbeyls
Date: Tue Jun 23 10:50:56 2015
New Revision: 240423

URL: http://llvm.org/viewvc/llvm-project?rev=240423&view=rev
Log:
Don't crash when aggregation of samples results in 0 value in ComparisonResult constructor.

Modified:
    lnt/trunk/lnt/server/reporting/analysis.py
    lnt/trunk/tests/server/reporting/analysis.py

Modified: lnt/trunk/lnt/server/reporting/analysis.py
URL: http://llvm.org/viewvc/llvm-project/lnt/trunk/lnt/server/reporting/analysis.py?rev=240423&r1=240422&r2=240423&view=diff
==============================================================================
--- lnt/trunk/lnt/server/reporting/analysis.py (original)
+++ lnt/trunk/lnt/server/reporting/analysis.py Tue Jun 23 10:50:56 2015
@@ -68,12 +68,12 @@ class ComparisonResult:
             self.previous = None
 
         # Compute the comparison status for the test value.
-        if self.current and self.previous and self.previous != 0:
+        self.delta = 0
+        self.pct_delta = 0.0
+        if self.current and self.previous:
             self.delta, value = absmin_diff(self.current, prev_samples)
-            self.pct_delta = self.delta / value
-        else:
-            self.delta = 0
-            self.pct_delta = 0.0
+            if value != 0:
+                self.pct_delta = self.delta / value
 
         # If we have multiple values for this run, use that to estimate the
         # distribution.

Modified: lnt/trunk/tests/server/reporting/analysis.py
URL: http://llvm.org/viewvc/llvm-project/lnt/trunk/tests/server/reporting/analysis.py?rev=240423&r1=240422&r2=240423&view=diff
==============================================================================
--- lnt/trunk/tests/server/reporting/analysis.py (original)
+++ lnt/trunk/tests/server/reporting/analysis.py Tue Jun 23 10:50:56 2015
@@ -6,6 +6,7 @@ import unittest
 from lnt.server.reporting.analysis import ComparisonResult, REGRESSED, IMPROVED
 from lnt.server.reporting.analysis import UNCHANGED_PASS, UNCHANGED_FAIL
 from lnt.server.reporting.analysis import absmin_diff
+from lnt.util.stats import median
 
 FLAT_LINE = [1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0,
              1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0]
@@ -298,6 +299,12 @@ class ComparisonResultTest(unittest.Test
         # Fixme
         # self.assertEquals(slow.get_value_status(), IMPROVED)
 
+    def test_handle_zero_sample(self):
+        for agfn in (min, median):
+            zeroSample = ComparisonResult(
+                agfn, False, False, [0.005, 0.0047, 0.0048], [0.0, 0.01, 0.01])
+            self.assertEquals(zeroSample.get_value_status(), UNCHANGED_PASS)
+
 
 class AbsMinTester(unittest.TestCase):