sync: fix pool wrap-around test
TestPoolDequeue in long mode does a little more than 1<<21 pushes.
This was originally because the head and tail indexes were 21 bits and
the intent was to test wrap-around behavior. However, in the final
version they were both 32 bits, so the test no longer tested
wrap-around.
It would take too long to reach 32-bit wrap around in a test, so
instead we initialize the poolDequeue with indexes that are already
nearly at their limit. This keeps the knowledge of the maximum index
in one place, and lets us test wrap-around even in short mode.
Change-Id: Ib9b8d85b6d9b5be235849c2b32e81c809e806579
Reviewed-on: https://go-review.googlesource.com/c/go/+/183979
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
diff --git a/src/sync/export_test.go b/src/sync/export_test.go
index 10d3599..ffbe567 100644
--- a/src/sync/export_test.go
+++ b/src/sync/export_test.go
@@ -18,9 +18,13 @@
}
func NewPoolDequeue(n int) PoolDequeue {
- return &poolDequeue{
+ d := &poolDequeue{
vals: make([]eface, n),
}
+ // For testing purposes, set the head and tail indexes close
+ // to wrapping around.
+ d.headTail = d.pack(1<<dequeueBits-500, 1<<dequeueBits-500)
+ return d
}
func (d *poolDequeue) PushHead(val interface{}) bool {
diff --git a/src/sync/pool_test.go b/src/sync/pool_test.go
index ff1174c..090f1a8 100644
--- a/src/sync/pool_test.go
+++ b/src/sync/pool_test.go
@@ -173,9 +173,7 @@
func testPoolDequeue(t *testing.T, d PoolDequeue) {
const P = 10
- // In long mode, do enough pushes to wrap around the 21-bit
- // indexes.
- N := 1<<21 + 1000
+ var N int = 2e6
if testing.Short() {
N = 1e3
}
