Keep HTTP/1 connection state after pipelined responses

[ericmj]

next_request/3 started the next queued response with decode(:status, %{conn | state: :status}, data, responses). decode/4 already takes the parser state as its first argument, and conn.state is the connection's own :open or :closed, so the struct update overwrote it with a parser state.

Once a response completed with another request in flight, open?/1 compared :status == :open and returned false, and close/1, whose clauses match :open and :closed, raised FunctionClauseError. Measured on the unfixed code: conn.state is :status after the first response, and HTTP1.close(conn) raises. Only pipelining reaches it: with nothing else in flight, next_request/3 matches its %{request: nil} clause, which buffers the rest and leaves the struct alone.

The test opens two requests, delivers the first response, and checks the connection is still open, the second response still parses, and close/1 works.

[coveralls]

Coverage Report for CI Build 7

Coverage remained the same at 88.627%

Details

• Coverage remained the same as the base build.
• Patch coverage: 1 of 1 lines across 1 file are fully covered (100%).
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	1741
Covered Lines:	1543
Line Coverage:	88.63%
Coverage Strength:	550.56 hits per line

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💛 - Coveralls