Golang Config.Import方法代码示例

func TestTransitivelyErrorFreeFlag(t *testing.T) {
	// Create an minimal custom build.Context
	// that fakes the following packages:
	//
	// a --> b --> c!   c has an error
	//   \              d and e are transitively error-free.
	//    e --> d
	//
	// Each package [a-e] consists of one file, x.go.
	pkgs := map[string]string{
		"a": `package a; import (_ "b"; _ "e")`,
		"b": `package b; import _ "c"`,
		"c": `package c; func f() { _ = int(false) }`, // type error within function body
		"d": `package d;`,
		"e": `package e; import _ "d"`,
	}
	conf := loader.Config{
		AllowErrors:   true,
		SourceImports: true,
		Build:         fakeContext(pkgs),
	}
	conf.Import("a")

	prog, err := conf.Load()
	if err != nil {
		t.Errorf("Load failed: %s", err)
	}
	if prog == nil {
		t.Fatalf("Load returned nil *Program")
	}

	for pkg, info := range prog.AllPackages {
		var wantErr, wantTEF bool
		switch pkg.Path() {
		case "a", "b":
		case "c":
			wantErr = true
		case "d", "e":
			wantTEF = true
		default:
			t.Errorf("unexpected package: %q", pkg.Path())
			continue
		}

		if (info.Errors != nil) != wantErr {
			if wantErr {
				t.Errorf("Package %q.Error = nil, want error", pkg.Path())
			} else {
				t.Errorf("Package %q has unexpected Errors: %v",
					pkg.Path(), info.Errors)
			}
		}

		if info.TransitivelyErrorFree != wantTEF {
			t.Errorf("Package %q.TransitivelyErrorFree=%t, want %t",
				pkg.Path(), info.TransitivelyErrorFree, wantTEF)
		}
	}
}

// Test that both syntax (scan/parse) and type errors are both recorded
// (in PackageInfo.Errors) and reported (via Config.TypeChecker.Error).
func TestErrorReporting(t *testing.T) {
	pkgs := map[string]string{
		"a": `package a; import _ "b"; var x int = false`,
		"b": `package b; 'syntax error!`,
	}
	conf := loader.Config{
		AllowErrors:   true,
		SourceImports: true,
		Build:         fakeContext(pkgs),
	}
	var mu sync.Mutex
	var allErrors []error
	conf.TypeChecker.Error = func(err error) {
		mu.Lock()
		allErrors = append(allErrors, err)
		mu.Unlock()
	}
	conf.Import("a")

	prog, err := conf.Load()
	if err != nil {
		t.Errorf("Load failed: %s", err)
	}
	if prog == nil {
		t.Fatalf("Load returned nil *Program")
	}

	// TODO(adonovan): test keys of ImportMap.

	// Check errors recorded in each PackageInfo.
	for pkg, info := range prog.AllPackages {
		switch pkg.Path() {
		case "a":
			if !hasError(info.Errors, "cannot convert false") {
				t.Errorf("a.Errors = %v, want bool conversion (type) error", info.Errors)
			}
		case "b":
			if !hasError(info.Errors, "rune literal not terminated") {
				t.Errorf("b.Errors = %v, want unterminated literal (syntax) error", info.Errors)
			}
		}
	}

	// Check errors reported via error handler.
	if !hasError(allErrors, "cannot convert false") ||
		!hasError(allErrors, "rune literal not terminated") {
		t.Errorf("allErrors = %v, want both syntax and type errors", allErrors)
	}
}

func generateSourceFiles(conf *loader.Config, subcommand string) (tmpDirPath string) {
	// Make a temp directory.
	tmpDir := makeTmpDir()
	if *work {
		// Print the name of the directory and don't clean it up on exit.
		fmt.Println(tmpDir)
	} else {
		// Clean up the directory on exit.
		atexit.Run(func() {
			removeDir(tmpDir)
		})
	}

	// Load the whole program from source files. This almost certainly causes more work than we need to do,
	// but it's an easy fix for a few problems I've encountered. Deleting this may be a good target for
	// future optimization work.
	conf.SourceImports = true

	// Mark the extra packages we want to instrument.
	var pkgs []string
	*instrument = strings.Trim(*instrument, ", ")
	if *instrument != "" {
		pkgs = strings.Split(*instrument, ",")
	}
	all := false
	for _, pkg := range pkgs {
		// check for the special reserved package names: "main", "all", and "std"
		// see 'go help packages'
		switch pkg {
		case "main":
			switch subcommand {
			case "run": // The main package is always instrumented anyway. Carry on.
			case "test":
				logFatal(`godebug test: can't pass reserved name "main" in the -instrument flag.`)
			}
		case "all":
			if !all {
				all = true
				fmt.Println(`godebug run: heads up: "all" means "all except std". godebug can't step into the standard library yet.` + "\n")
			}
		case "std":
			logFatalf("godebug %s: reserved name \"std\" cannot be passed in the -instrument flag."+
				"\ngodebug cannot currently instrument packages in the standard library."+
				"\nDo you wish it could? Chime in at https://github.com/mailgun/godebug/issues/12",
				subcommand)
		default:
			for _, path := range gotool.ImportPaths([]string{pkg}) { // wildcard "..." expansion
				conf.Import(path)
			}
		}
	}

	// Load the program.
	prog, err := conf.Load()
	exitIfErr(err)

	// If we're in "all" mode, mark all but the standard library packages and godebug itself for instrumenting.
	stdLib := getStdLibPkgs()
	if all {
		markAlmostAllPackages(prog, stdLib)
	}

	// Warn the user if they have breakpoints set in files that we are not instrumenting.
	checkForUnusedBreakpoints(subcommand, prog, stdLib)

	// Generate debugging-enabled source files.
	wd := getwd()
	gen.Generate(prog, ioutil.ReadFile, func(importPath, filename string) io.WriteCloser {
		if importPath == "main" {
			filename = filepath.Join(tmpDir, filepath.Base(filename))
		} else {
			importPath, _ = findUnderGopath(wd, importPath)
			exitIfErr(os.MkdirAll(filepath.Join(tmpDir, "src", importPath), 0770))
			filename = filepath.Join(tmpDir, "src", importPath, filepath.Base(filename))
		}
		return createFileHook(filename, tmpDir)
	})
	return tmpDir
}

func TestCgoOption(t *testing.T) {
	switch runtime.GOOS {
	// On these systems, the net and os/user packages don't use cgo.
	case "plan9", "solaris", "windows":
		return
	}
	// In nocgo builds (e.g. linux-amd64-nocgo),
	// there is no "runtime/cgo" package,
	// so cgo-generated Go files will have a failing import.
	if !build.Default.CgoEnabled {
		return
	}
	// Test that we can load cgo-using packages with
	// CGO_ENABLED=[01], which causes go/build to select pure
	// Go/native implementations, respectively, based on build
	// tags.
	//
	// Each entry specifies a package-level object and the generic
	// file expected to define it when cgo is disabled.
	// When cgo is enabled, the exact file is not specified (since
	// it varies by platform), but must differ from the generic one.
	//
	// The test also loads the actual file to verify that the
	// object is indeed defined at that location.
	for _, test := range []struct {
		pkg, name, genericFile string
	}{
		{"net", "cgoLookupHost", "cgo_stub.go"},
		{"os/user", "lookupId", "lookup_stubs.go"},
	} {
		ctxt := build.Default
		for _, ctxt.CgoEnabled = range []bool{false, true} {
			conf := loader.Config{Build: &ctxt}
			conf.Import(test.pkg)
			prog, err := conf.Load()
			if err != nil {
				t.Errorf("Load failed: %v", err)
				continue
			}
			info := prog.Imported[test.pkg]
			if info == nil {
				t.Errorf("package %s not found", test.pkg)
				continue
			}
			obj := info.Pkg.Scope().Lookup(test.name)
			if obj == nil {
				t.Errorf("no object %s.%s", test.pkg, test.name)
				continue
			}
			posn := prog.Fset.Position(obj.Pos())
			t.Logf("%s: %s (CgoEnabled=%t)", posn, obj, ctxt.CgoEnabled)

			gotFile := filepath.Base(posn.Filename)
			filesMatch := gotFile == test.genericFile

			if ctxt.CgoEnabled && filesMatch {
				t.Errorf("CGO_ENABLED=1: %s found in %s, want native file",
					obj, gotFile)
			} else if !ctxt.CgoEnabled && !filesMatch {
				t.Errorf("CGO_ENABLED=0: %s found in %s, want %s",
					obj, gotFile, test.genericFile)
			}

			// Load the file and check the object is declared at the right place.
			b, err := ioutil.ReadFile(posn.Filename)
			if err != nil {
				t.Errorf("can't read %s: %s", posn.Filename, err)
				continue
			}
			line := string(bytes.Split(b, []byte("\n"))[posn.Line-1])
			ident := line[posn.Column-1:]
			if !strings.HasPrefix(ident, test.name) {
				t.Errorf("%s: %s not declared here (looking at %q)", posn, obj, ident)
			}
		}
	}
}