feat: first class build targets (#3062)

Adds the ability to tell goreleaser to use the first-class Go ports as
targets.

Closes #3053

Signed-off-by: Carlos A Becker <caarlos0@gmail.com>

internal/builders/golang/build.go

@@ -68,29 +68,67 @@ func (*Builder) WithDefaults(build config.Build) (config.Build, error) {
 			build.Goamd64 = []string{"v1"}
 		}
 		targets, err := buildtarget.List(build)
-		build.Targets = targets
 		if err != nil {
 			return build, err
 		}
+		build.Targets = targets
 	} else {
-		for i, target := range build.Targets {
+		targets := map[string]bool{}
+		for _, target := range build.Targets {
+			if target == go118FirstClassTargetsName ||
+				target == goStableFirstClassTargetsName {
+				for _, t := range go118FirstClassTargets {
+					targets[t] = true
+				}
+				continue
+			}
 			if strings.HasSuffix(target, "_amd64") {
-				build.Targets[i] = target + "_v1"
+				targets[target+"_v1"] = true
+				continue
 			}
 			if strings.HasSuffix(target, "_arm") {
-				build.Targets[i] = target + "_6"
+				targets[target+"_6"] = true
+				continue
 			}
 			if strings.HasSuffix(target, "_mips") ||
 				strings.HasSuffix(target, "_mips64") ||
 				strings.HasSuffix(target, "_mipsle") ||
 				strings.HasSuffix(target, "_mips64le") {
-				build.Targets[i] = target + "_hardfloat"
+				targets[target+"_hardfloat"] = true
+				continue
 			}
+			targets[target] = true
 		}
+		build.Targets = keys(targets)
 	}
 	return build, nil
 }
 
+func keys(m map[string]bool) []string {
+	result := make([]string, 0, len(m))
+	for k := range m {
+		result = append(result, k)
+	}
+	return result
+}
+
+const (
+	go118FirstClassTargetsName    = "go_118_first_class"
+	goStableFirstClassTargetsName = "go_first_class"
+)
+
+// go tool dist list -json | jq -r '.[] | select(.FirstClass) | [.GOOS, .GOARCH] | @tsv'
+var go118FirstClassTargets = []string{
+	"darwin_amd64_v1",
+	"darwin_arm64",
+	"linux_386",
+	"linux_amd64_v1",
+	"linux_arm_6",
+	"linux_arm64",
+	"windows_386",
+	"windows_amd64_v1",
+}
+
 // Build builds a golang build.
 func (*Builder) Build(ctx *context.Context, build config.Build, options api.Options) error {
 	if err := checkMain(build); err != nil {

internal/builders/golang/build_test.go

@@ -185,6 +185,42 @@ func TestWithDefaults(t *testing.T) {
 			},
 			goBinary: "go",
 		},
+		"go first class targets": {
+			build: config.Build{
+				ID:      "foo3",
+				Binary:  "foo",
+				Targets: []string{goStableFirstClassTargetsName},
+			},
+			targets:  go118FirstClassTargets,
+			goBinary: "go",
+		},
+		"go 1.18 first class targets": {
+			build: config.Build{
+				ID:      "foo3",
+				Binary:  "foo",
+				Targets: []string{go118FirstClassTargetsName},
+			},
+			targets:  go118FirstClassTargets,
+			goBinary: "go",
+		},
+		"go 1.18 first class targets plus custom": {
+			build: config.Build{
+				ID:      "foo3",
+				Binary:  "foo",
+				Targets: []string{"linux_amd64_v1", go118FirstClassTargetsName, "darwin_amd64_v2"},
+			},
+			targets:  append(go118FirstClassTargets, "darwin_amd64_v2"),
+			goBinary: "go",
+		},
+		"repeatin targets": {
+			build: config.Build{
+				ID:      "foo3",
+				Binary:  "foo",
+				Targets: []string{go118FirstClassTargetsName, go118FirstClassTargetsName, goStableFirstClassTargetsName},
+			},
+			targets:  go118FirstClassTargets,
+			goBinary: "go",
+		},
 	} {
 		t.Run(name, func(t *testing.T) {
 			if testcase.build.GoBinary != "" && testcase.build.GoBinary != "go" {