net/http: fix TestTransportServerClosingUnexpectedly flake

Fixes #32119

Change-Id: I8cf2e2e69737e2485568af91ab75149f3cf66781
Reviewed-on: https://go-review.googlesource.com/c/go/+/178918
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

1 files changed, 15 insertions, 0 deletions

diff --git a/src/net/http/export_test.go b/src/net/http/export_test.go
index b6965c239e..c33b88860a 100644
--- a/src/net/http/export_test.go
+++ b/src/net/http/export_test.go
@@ -244,3 +244,18 @@ func ExportSetH2GoawayTimeout(d time.Duration) (restore func()) {
 }
 
 func (r *Request) ExportIsReplayable() bool { return r.isReplayable() }
+
+// ExportCloseTransportConnsAbruptly closes all idle connections from
+// tr in an abrupt way, just reaching into the underlying Conns and
+// closing them, without telling the Transport or its persistConns
+// that it's doing so. This is to simulate the server closing connections
+// on the Transport.
+func ExportCloseTransportConnsAbruptly(tr *Transport) {
+	tr.idleMu.Lock()
+	for _, pcs := range tr.idleConn {
+		for _, pc := range pcs {
+			pc.conn.Close()
+		}
+	}
+	tr.idleMu.Unlock()
+}