gopls/internal/regtest/bench: add benchmarks for codeactions

Add missing benchmarks for codeactions.

For golang/go#61508

Change-Id: I260fdae1c70c2e2291b7469cb7240d3d68cf1ded
Reviewed-on: https://go-review.googlesource.com/c/tools/+/512495
Run-TryBot: Robert Findley <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Reviewed-by: Alan Donovan <[email protected]>
gopls-CI: kokoro <[email protected]>

Author: findleyr

gopls/internal/regtest/bench/codeaction_test.go

@@ -0,0 +1,69 @@
+// 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.
+
+package bench
+
+import (
+	"fmt"
+	"sync/atomic"
+	"testing"
+
+	"golang.org/x/tools/gopls/internal/lsp/protocol"
+)
+
+func BenchmarkCodeAction(b *testing.B) {
+	for _, test := range didChangeTests {
+		b.Run(test.repo, func(b *testing.B) {
+			env := getRepo(b, test.repo).sharedEnv(b)
+			env.OpenFile(test.file)
+			defer closeBuffer(b, env, test.file)
+			env.AfterChange()
+
+			env.CodeAction(test.file, nil) // pre-warm
+
+			b.ResetTimer()
+
+			if stopAndRecord := startProfileIfSupported(b, env, qualifiedName(test.repo, "hover")); stopAndRecord != nil {
+				defer stopAndRecord()
+			}
+
+			for i := 0; i < b.N; i++ {
+				env.CodeAction(test.file, nil)
+			}
+		})
+	}
+}
+
+func BenchmarkCodeActionFollowingEdit(b *testing.B) {
+	for _, test := range didChangeTests {
+		b.Run(test.repo, func(b *testing.B) {
+			env := getRepo(b, test.repo).sharedEnv(b)
+			env.OpenFile(test.file)
+			defer closeBuffer(b, env, test.file)
+			env.EditBuffer(test.file, protocol.TextEdit{NewText: "// __REGTEST_PLACEHOLDER_0__\n"})
+			env.AfterChange()
+
+			env.CodeAction(test.file, nil) // pre-warm
+
+			b.ResetTimer()
+
+			if stopAndRecord := startProfileIfSupported(b, env, qualifiedName(test.repo, "hover")); stopAndRecord != nil {
+				defer stopAndRecord()
+			}
+
+			for i := 0; i < b.N; i++ {
+				edits := atomic.AddInt64(&editID, 1)
+				env.EditBuffer(test.file, protocol.TextEdit{
+					Range: protocol.Range{
+						Start: protocol.Position{Line: 0, Character: 0},
+						End:   protocol.Position{Line: 1, Character: 0},
+					},
+					// Increment the placeholder text, to ensure cache misses.
+					NewText: fmt.Sprintf("// __REGTEST_PLACEHOLDER_%d__\n", edits),
+				})
+				env.CodeAction(test.file, nil)
+			}
+		})
+	}
+}