x/tools/internal/jsonrpc2_v2: failures with "connection refused"

[bcmills]

#!watchflakes
post <- pkg == "golang.org/x/tools/internal/jsonrpc2_v2" && `connection refused`

greplogs --dashboard -md -l -e '(?ms)connection refused.*FAIL\s+golang\.org/x/tools/internal/jsonrpc2_v2' --since=2021-06-03

2021-11-05T04:20:33-6f75aad-0a5ca24/solaris-amd64-oraclerel

--- FAIL: TestIdleTimeout (0.23s)
    serve_test.go:38: dial tcp 127.0.0.1:57098: connect: connection refused
FAIL
FAIL	golang.org/x/tools/internal/jsonrpc2_v2	0.616s

2021-11-03T20:51:16-84e69e7-88407a8/openbsd-amd64-68
2021-10-09T14:53:12-ee04797-eba91e8/dragonfly-amd64
2021-10-08T19:19:09-c5188f2-b9e1e1b/openbsd-amd64-64
2021-09-24T07:22:13-6d1e33f-d413908/plan9-arm
2021-09-19T16:34:52-7559231-771b8ea/freebsd-amd64-race
2021-08-18T22:16:57-bf6c7f2-eda3de0/solaris-amd64-oraclerel
2021-08-02T20:18:28-bb69444-8a7ee4c/freebsd-386-11_4
2021-07-13T20:15:39-ef97713-a985897/solaris-amd64-oraclerel
2021-07-08T19:56:33-febfa9d-3d1d066/linux-amd64-wsl

--- FAIL: TestServe (1.49s)
    --- FAIL: TestServe/tcp (1.47s)
        serve_test.go:104: dial tcp 127.0.0.1:43425: connect: connection refused
FAIL
FAIL	golang.org/x/tools/internal/jsonrpc2_v2	1.801s

2021-07-08T19:53:41-c979f92-296ddf2/linux-amd64-wsl
2021-07-08T17:53:43-55cd480-296ddf2/linux-amd64-wsl
2021-06-24T04:20:08-4833ac5-0e7012e/darwin-amd64-nocgo

Likely related to #46520.

[gopherbot]

Change https://go.dev/cl/388598 mentions this issue: internal/jsonrpc2_v2: eliminate arbitrary timeouts in tests

[gopherbot]

Change https://go.dev/cl/388597 mentions this issue: internal/jsonrpc2_v2: refactor concurrency in idleListener

[gopherbot]

Change https://go.dev/cl/388134 mentions this issue: internal/jsonrpc2_v2: rework Connection concurrency

[gopherbot]

Change https://go.dev/cl/388600 mentions this issue: internal/lsp/protocol: avoid replying with non-nil interface values in case of error

[gopherbot]

Change https://go.dev/cl/388775 mentions this issue: internal/jsonrpc2_v2: error out in-flight client calls when the reader breaks

[heschi]

2022-07-01T14:13:48-ffc70b9-8d2935a/freebsd-amd64-12_3