cmd/vet: add slog checker

Add the slog static analysis pass to `go vet`.

Vendor in golang.org/x/tools@master to pick up the pass.

Tweak a test in slog to avoid triggering the vet check.

Change-Id: I55ceac9a4e6876c8385897784542761ea0af2481
Reviewed-on: https://go-review.googlesource.com/c/go/+/496156
Reviewed-by: Alan Donovan <adonovan@google.com>
Run-TryBot: Jonathan Amsterdam <jba@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>

1 files changed, 13 insertions, 0 deletions

diff --git a/src/cmd/vet/testdata/slog/slog.go b/src/cmd/vet/testdata/slog/slog.go
new file mode 100644
index 0000000000..accb04361b
--- /dev/null
+++ b/src/cmd/vet/testdata/slog/slog.go
@@ -0,0 +1,13 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file contains tests for the slog checker.
+
+package slog
+
+import "log/slog"
+
+func SlogTest() {
+	slog.Info("msg", "a") // ERROR "call to slog.Info missing a final value"
+}