tools/syz-testbed: fix relative value change computation

It's perfectly normal for a column value not to be present -- e.g. when
we compare syzkaller branches that don't use the same statistics.

1 files changed, 27 insertions, 0 deletions

diff --git a/tools/syz-testbed/table_test.go b/tools/syz-testbed/table_test.go
new file mode 100644
index 000000000..fb07e7804
--- /dev/null
+++ b/tools/syz-testbed/table_test.go
@@ -0,0 +1,27 @@
+// Copyright 2024 syzkaller project authors. All rights reserved.
+// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
+
+package main
+
+import (
+	"testing"
+
+	"github.com/google/syzkaller/pkg/stats"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestRelativeValues(t *testing.T) {
+	table := NewTable("", "A", "B")
+	table.Set("row1", "A", NewValueCell(&stats.Sample{Xs: []float64{2, 2}}))
+	table.Set("row1", "B", NewValueCell(&stats.Sample{Xs: []float64{3, 3}}))
+	// Don't set row2/A.
+	table.Set("row2", "B", NewValueCell(&stats.Sample{Xs: []float64{1, 1}}))
+
+	err := table.SetRelativeValues("A")
+	assert.NoError(t, err)
+
+	assert.InDelta(t, 50.0, *table.Get("row1", "B").(*ValueCell).PercentChange, 0.1)
+	assert.Nil(t, table.Get("row1", "A").(*ValueCell).PercentChange)
+	assert.Nil(t, table.Get("row2", "A"))
+	assert.Nil(t, table.Get("row2", "B").(*ValueCell).PercentChange)
+}