dashboard: only test nounified on release-branch.go1.20

With Go 1.20, we've switched the default to GOEXPERIMENT=unified, but
still support GOEXPERIMENT=nounified. For Go 1.21, we're going to
remove the experiment knob.

This CL updates the builders accordingly: continues to test
GOEXPERIMENT=nounified only for the 1.20 release branch, and stops
testing GOEXPERIMENT=unified entirely (since that's the default
everywhere we care about testing it).

Fixes golang/go#52150.
Fixes golang/go#57977.

Change-Id: Ice5be7c3db3453989ab12a48e2c93760590492ef
Reviewed-on: https://go-review.googlesource.com/c/build/+/463156
Reviewed-by: Dmitri Shuralyov <[email protected]>
Run-TryBot: Matthew Dempsky <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>

Author: mdempsky

dashboard/builders.go

@@ -1646,34 +1646,15 @@ func init() {
 			"GOEXPERIMENT=staticlockranking",
 		},
 	})
-	addBuilder(BuildConfig{
-		Name:     "linux-amd64-unified",
-		HostType: "host-linux-amd64-buster",
-		Notes:    "builder with GOEXPERIMENT=unified, see go.dev/issue/46786",
-		tryBot: func(repo, branch, goBranch string) bool {
-			// TODO(go.dev/issue/52150): Restore testing against tools repo.
-			return (repo == "go" /*|| repo == "tools"*/) && (goBranch == "master" || goBranch == "dev.unified")
-		},
-		buildsRepo: func(repo, branch, goBranch string) bool {
-			return (repo == "go" || repo == "tools") && (goBranch == "master" || goBranch == "dev.unified")
-		},
-		env: []string{
-			"GO_DISABLE_OUTBOUND_NETWORK=1",
-			"GOEXPERIMENT=unified",
-		},
-		numTestHelpers:    1,
-		numTryTestHelpers: 4,
-		KnownIssues:       []int{52150},
-	})
 	addBuilder(BuildConfig{
 		Name:     "linux-amd64-nounified",
 		HostType: "host-linux-amd64-buster",
-		Notes:    "builder with GOEXPERIMENT=nounified, see go.dev/issue/51397",
+		Notes:    "builder with GOEXPERIMENT=nounified, see go.dev/issue/51397 and go.dev/issue/57977",
 		tryBot: func(repo, branch, goBranch string) bool {
-			return (repo == "go" || repo == "tools") && (goBranch == "master" || goBranch == "dev.unified")
+			return (repo == "go" || repo == "tools") && goBranch == "release-branch.go1.20"
 		},
 		buildsRepo: func(repo, branch, goBranch string) bool {
-			return (repo == "go" || repo == "tools") && (goBranch == "master" || goBranch == "dev.unified")
+			return (repo == "go" || repo == "tools") && goBranch == "release-branch.go1.20"
 		},
 		env: []string{
 			"GO_DISABLE_OUTBOUND_NETWORK=1",

dashboard/builders_test.go

@@ -98,9 +98,7 @@ func TestTrybots(t *testing.T) {
 				"linux-386",
 				"linux-amd64",
 				"linux-amd64-boringcrypto",
-				"linux-amd64-nounified",
 				"linux-amd64-race",
-				"linux-amd64-unified",
 				"linux-arm-aws",
 				"linux-arm64",
 				"openbsd-amd64-72",
@@ -134,6 +132,7 @@ func TestTrybots(t *testing.T) {
 				"linux-386",
 				"linux-amd64",
 				"linux-amd64-boringcrypto",
+				"linux-amd64-nounified",
 				"linux-amd64-race",
 				"linux-arm-aws",
 				"linux-arm64",
@@ -579,19 +578,12 @@ func TestBuilderConfig(t *testing.T) {
 		{b("[email protected]", "go"), onlyPost},
 		{b("linux-amd64-staticlockranking", "net"), none},
 
-		{b("linux-amd64-unified", "go"), both},
-		{b("linux-amd64-unified", "tools"), onlyPost},
-		{b("linux-amd64-unified", "net"), none},
-		{b("[email protected]", "go"), both},
-		{b("[email protected]", "tools"), onlyPost},
-		{b("[email protected]", "net"), none},
-
-		{b("linux-amd64-nounified", "go"), both},
-		{b("linux-amd64-nounified", "tools"), both},
+		{b("linux-amd64-nounified", "go"), none},
+		{b("linux-amd64-nounified", "tools"), none},
 		{b("linux-amd64-nounified", "net"), none},
-		{b("linux-amd64-nounified@dev.unified", "go"), both},
-		{b("linux-amd64-nounified@dev.unified", "tools"), both},
-		{b("linux-amd64-nounified@dev.unified", "net"), none},
+		{b("linux-amd64-nounified@go1.20", "go"), both},
+		{b("linux-amd64-nounified@go1.20", "tools"), both},
+		{b("linux-amd64-nounified@go1.20", "net"), none},
 	}
 	for _, tt := range tests {
 		t.Run(tt.br.testName, func(t *testing.T) {