gopls/internal/settings: deprecate "allowImplicitNetworkAccess"

This setting changes the behavior of gopls in fundamental low-level
ways, and therefore is severely under-tested and now worth maintaining.
Gopls should make accurate decisions about whether to allow network
access for commands.

Fixes golang/go#66860

Change-Id: Ia2f58bf146fc6bd37d769b65fc227cb2d0027032
Reviewed-on: https://go-review.googlesource.com/c/tools/+/579437
Reviewed-by: Alan Donovan <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>
Auto-Submit: Robert Findley <[email protected]>

Author: findleyr

gopls/doc/release/v0.16.0.md

@@ -10,6 +10,9 @@ go install golang.org/x/tools/[email protected]
   that if your LSP client is able and configured to request semantic tokens,
   gopls will provide them. The default was previously false because VS Code
   historically provided no client-side way for users to disable the feature.
+- The experimental "allowImplicitNetworkAccess" setting is deprecated (but not
+  yet removed). Please comment on https://go.dev/issue/66861 if you use this
+  setting and would be impacted by its removal.
 
 ## New features
 

gopls/internal/settings/settings.go

@@ -985,6 +985,7 @@ func (o *Options) set(name string, value interface{}, seen map[string]struct{})
 		result.deprecated("")
 
 	case "allowImplicitNetworkAccess":
+		result.softErrorf("gopls setting \"allowImplicitNetworkAccess\" is deprecated.\nPlease comment on https://go.dev/issue/66861 if this impacts your workflow.")
 		result.setBool(&o.AllowImplicitNetworkAccess)
 
 	case "experimentalUseInvalidMetadata":

gopls/internal/test/integration/misc/configuration_test.go

@@ -239,6 +239,7 @@ func TestDeprecatedSettings(t *testing.T) {
 			"experimentalWorkspaceModule":    true,
 			"tempModfile":                    true,
 			"allowModfileModifications":      true,
+			"allowImplicitNetworkAccess":     true,
 		},
 	).Run(t, "", func(t *testing.T, env *Env) {
 		env.OnceMet(
@@ -248,6 +249,7 @@ func TestDeprecatedSettings(t *testing.T) {
 			ShownMessage("experimentalWatchedFileDelay"),
 			ShownMessage("tempModfile"),
 			ShownMessage("allowModfileModifications"),
+			ShownMessage("allowImplicitNetworkAccess"),
 		)
 	})
 }