Rob Findley 88be01311a internal/jsonrpc2: fix races in cancellation ... We had a deadlock in cases where a request was cancelled (1) after being written to the stream, but (2) before a response was received. This resulted in the request ID being removed from the pending map while the server has the request, after which point the server response would hang in Conn.Run trying to send to a nil channel. After fixing this nil send there was still a race: it was possible that Conn.Run could get the pending request, and Conn.Call would select ctx.Done before Conn.Run could send to the response channel, again resulting in a blocking send. Fix this by adding a buffer to the response channel. The response channel management is also made less forgiving, because we should be able to reason precisely about how many sends and receives will occur: + Don't close the response channel after sending a response: there should only be one recipient. + Don't delete the ID from pending map twice: it should only be cleaned up by Conn.Call. Cancellation tests in the lsprpc package are updated to exercise the race conditions. Fixes golang/go#37159 Change-Id: Ie3207442ea910f79247b18d8647fd52f39fb15db Reviewed-on: https://go-review.googlesource.com/c/tools/+/219126 Run-TryBot: Robert Findley <rfindley@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Heschi Kreinick <heschi@google.com>		2020-02-14 14:43:24 +00:00
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lsprpc_test.go	internal/jsonrpc2: fix races in cancellation	2020-02-14 14:43:24 +00:00
lsprpc.go	internal/lsp/lsprpc: add an LSP forwarder and regtest environment	2020-02-14 14:21:06 +00:00
telemetry.go	internal/lsp: refactor LSP server instantiation	2020-02-06 23:12:37 +00:00