doc: document new http.Transport limit on 1xx responses

Fixes #65035

Change-Id: I3b0586b5e2a0729e6b252d2bcd4139c99bc80733
Reviewed-on: https://go-review.googlesource.com/c/go/+/622335
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Damien Neil <dneil@google.com>
Reviewed-by: Jonathan Amsterdam <jba@google.com>

diff --git a/doc/next/6-stdlib/99-minor/net/http/65035.md b/doc/next/6-stdlib/99-minor/net/http/65035.md
new file mode 100644 (file)
index 0000000..5368aad
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+++ b/doc/next/6-stdlib/99-minor/net/http/65035.md
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+[Transport]'s limit on 1xx informational responses received
+in response to a request has changed.
+It previously aborted a request and returned an error after
+receiving more than 5 1xx responses.
+It now returns an error if the total size of all 1xx responses
+exceeds the [Transport.MaxResponseHeaderBytes] configuration setting.
+
+In addition, when a request has a
+[net/http/httptrace.ClientTrace.Got1xxResponse]
+trace hook, there is now no limit on the total number of 1xx responses.
+The `Got1xxResponse` hook may return an error to abort a request.