// tag::configuration[]
// Using the Java API
println(System.getenv("ENVIRONMENTAL"))

// Using the Gradle API, provides a lazy Provider<String>
println(providers.environmentVariable("ENVIRONMENTAL").get())

// end::configuration[]

abstract class PrintValue : DefaultTask() {
    @get:Input abstract val inputValue: Property<String>
    @TaskAction fun action() { println(inputValue.get()) }
}

// tag::execution[]

	if err != nil {
		log.Fatal(err)
	}

	if os.Getenv("GO111MODULE") == "on" {
		out, err := exec.Command("go", "env", "GOMOD").Output()
		if err != nil {
			log.Fatal(err)
		}
		modRoot := filepath.Dir(strings.TrimSpace(string(out)))
		check(data, "module root", modRoot)
	} else {
		check(data, "GOPATH", os.Getenv("GOPATH"))
	}
	check(data, "GOROOT", os.Getenv("GOROOT"))
}

    interface Parameters extends ValueSourceParameters {
        Property<String> getSubstring()
    }

    Map<String, String> obtain() {
        return System.getenv().findAll { key, _ ->
            key.contains(parameters.substring.get())
        }
    }
}
// end::value-source[]

// tag::create-provider[]

	if err != nil {
		fmt.Fprintf(os.Stderr, "error: coverage meta-data prep failed: %v\n", err)
		if os.Getenv("GOCOVERDEBUG") != "" {
			panic("meta-data write failure")
		}
	}
	if len(ml) == 0 {
		fmt.Fprintf(os.Stderr, "program not built with -cover\n")
		return
	}

	goCoverDir = os.Getenv("GOCOVERDIR")
	if goCoverDir == "" {
		fmt.Fprintf(os.Stderr, "warning: GOCOVERDIR not set, no coverage data emitted\n")

func Builder() string {
	return os.Getenv("GO_BUILDER_NAME")
}

// HasGoBuild reports whether the current system can build programs with “go build”
// and then run them with os.StartProcess or exec.Command.
func HasGoBuild() bool {
	if os.Getenv("GO_GCFLAGS") != "" {
		// It's too much work to require every caller of the go command
		// to pass along "-gcflags="+os.Getenv("GO_GCFLAGS").

cp stdout go.mod

go list -modfile=go.mod all
-- print_go_mod.go --
//go:build ignore
package main

import (
    "fmt"
    "os"
)

func main() {
    work := os.Getenv("WORK")
fmt.Printf(`module example.com/mod

require b.com v0.0.0

replace b.com => %s\gopath\src/modb
`,  work)
}
-- a.go --
package a

import _ "b.com/b"
-- modb/go.mod --
module b.com

		os.WriteFile(filepath.Join(dir, "README"), []byte(cacheREADME), 0666)
	}

	diskCache, err := Open(dir)
	if err != nil {
		base.Fatalf("failed to initialize build cache at %s: %s\n", dir, err)
	}

	if v := cfg.Getenv("GOCACHEPROG"); v != "" && goexperiment.CacheProg {
		defaultCache = startCacheProg(v, diskCache)
	} else {
		defaultCache = diskCache
	}
}

var (
	defaultDirOnce    sync.Once
	defaultDir        string

	if *target != "" {
		f := strings.Split(*target, "/")
		if len(f) != 2 {
			t.Fatalf("-target argument must be goos/goarch")
		}
		defer os.Setenv("GOOS", os.Getenv("GOOS"))
		defer os.Setenv("GOARCH", os.Getenv("GOARCH"))
		os.Setenv("GOOS", f[0])
		os.Setenv("GOARCH", f[1])
		goarch = f[1]
	}

	hash := notsha256.Sum256([]byte(fmt.Sprintf("%v-%v-%v-%v", srcfname, flags, printCode, printGnuAsm)))

	b.WriteString(fmt.Sprintf("ISTIO_OUTBOUND_PORTS=%s\n", os.Getenv("ISTIO_OUTBOUND_PORTS")))
	b.WriteString(fmt.Sprintf("ISTIO_LOCAL_EXCLUDE_PORTS=%s\n", os.Getenv("ISTIO_LOCAL_EXCLUDE_PORTS")))
	b.WriteString(fmt.Sprintf("ISTIO_EXCLUDE_INTERFACES=%s\n", os.Getenv("ISTIO_EXCLUDE_INTERFACES")))
	b.WriteString(fmt.Sprintf("ISTIO_SERVICE_CIDR=%s\n", os.Getenv("ISTIO_SERVICE_CIDR")))

		}
	}
}

func TestCallRunInCleanupHelper(t *testing.T) {
	if os.Getenv("GO_WANT_HELPER_PROCESS") != "1" {
		return
	}

	t.Cleanup(func() {
		t.Run("in-cleanup", func(t *testing.T) {
			t.Log("must not be executed")
		})
	})
}

func TestGoexitInCleanupAfterPanicHelper(t *testing.T) {
	if os.Getenv("GO_WANT_HELPER_PROCESS") != "1" {
		return
	}