doc/go1.20: add section on coverage

Add some basic material on the changes to code coverage testing
to the release notes.

For #54202.

Change-Id: I28200d43b4952ce8e8ecf46c8fe8e97c81d245e5
Reviewed-on: https://go-review.googlesource.com/c/go/+/453857
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Than McIntosh <thanm@google.com>
Reviewed-by: Eli Bendersky <eliben@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>

diff --git a/doc/go1.20.html b/doc/go1.20.html
index f53680e3ba4fd95767172e0e3637b76bdce9dea0..d14034c2f50f3042ef921b6aff0295323f2e4019 100644 (file)
--- a/doc/go1.20.html
+++ b/doc/go1.20.html
@@ -175,6 +175,14 @@ Do not send CLs removing the interior tags from such phrases.
   Specifying <code>-pgo=off</code> turns off profile-guided optimization.
 </p>
 
+<p><!-- https://go.dev/issue/51430 -->
+  The <code>go</code> <code>build</code>, <code>go</code> <code>install</code>,
+  and other build-related commands now support a <code>-cover</code>
+  flag that builds the specified target with code coverage instrumentation.
+  This is described in more detail in the
+  <a href="#cover">Cover</a> section below.
+</p>
+
 <h4 id="go-version"><code>go</code> <code>version</code></h4>
 
 <p><!-- https://go.dev/issue/48187 -->
@@ -228,7 +236,19 @@ Do not send CLs removing the interior tags from such phrases.
 <h3 id="cover">Cover</h3>
 
 <p><!-- CL 436236, CL 401236, CL 438503 -->
-  TODO coverage
+  Go 1.20 supports collecting code coverage profiles for programs
+  (applications and integration tests), as opposed to just unit tests.
+</p>
+
+<p>
+  To collect coverage data for a program, build it with <code>go</code>
+  <code>build</code>'s <code>-cover</code> flag, then run the resulting
+  binary with the environment variable <code>GOCOVERDIR</code> set
+  to an output directory for coverage profiles.
+  See the
+  <a href="https://go.dev/testing/coverage">'coverage for integration tests' landing page</a> for more on how to get started.
+  For details on the design and implementation, see the
+  <a href="https://golang.org/issue/51430">proposal</a>.
 </p>
 
 <h3 id="vet">Vet</h3>
@@ -285,6 +305,13 @@ Do not send CLs removing the interior tags from such phrases.
   assists in some circumstances.
 </p>
 
+<p><!-- https://go.dev/issue/51430 -->
+  Go 1.20 adds a new <code>runtime/coverage</code> package
+  containing APIs for writing coverage profile data at
+  runtime from a long-running and/or server programs that
+  do not terminate via <code>os.Exit()</code>.
+</p>
+
 <h2 id="compiler">Compiler</h2>
 
 <p><!-- https://go.dev/issue/55022 -->