Exemple #1
0
// Name = identifier | "?" | QualifiedName .
//
// If materializePkg is set, the returned package is guaranteed to be set.
// For fully qualified names, the returned package may be a fake package
// (without name, scope, and not in the p.imports map), created for the
// sole purpose of providing a package path. Fake packages are created
// when the package id is not found in the p.imports map; in that case
// we cannot create a real package because we don't have a package name.
// For non-qualified names, the returned package is the imported package.
//
func (p *parser) parseName(materializePkg bool) (pkg *types.Package, name string) {
	switch p.tok {
	case scanner.Ident:
		pkg = p.imports[p.id]
		name = p.lit
		p.next()
	case '?':
		// anonymous
		pkg = p.imports[p.id]
		p.next()
	case '@':
		// exported name prefixed with package path
		var id string
		id, name = p.parseQualifiedName()
		if materializePkg {
			// we don't have a package name - if the package
			// doesn't exist yet, create a fake package instead
			pkg = p.getPkg(id, "")
			if pkg == nil {
				pkg = types.NewPackage(id, "")
			}
		}
	default:
		p.error("name expected")
	}
	return
}
Exemple #2
0
func (p *importer) fieldName(parent *types.Package) (*types.Package, string) {
	name := p.string()
	pkg := parent
	if pkg == nil {
		// use the imported package instead
		pkg = p.pkgList[0]
	}
	if p.version == 0 && name == "_" {
		// version 0 didn't export a package for _ fields
		// see issue #15514

		// For bug-compatibility with gc, pretend all imported
		// blank fields belong to the same dummy package.
		// This avoids spurious "cannot assign A to B" errors
		// from go/types caused by types changing as they are
		// re-exported.
		const blankpkg = "<_>"
		pkg := p.imports[blankpkg]
		if pkg == nil {
			pkg = types.NewPackage(blankpkg, blankpkg)
			p.imports[blankpkg] = pkg
		}

		return pkg, name
	}
	if name != "" && !exported(name) {
		if name == "?" {
			name = ""
		}
		pkg = p.pkg()
	}
	return pkg, name
}
Exemple #3
0
func NewPackage(path, name string) *Package {
	return &Package{
		types.NewPackage(path, name),
		token.NewFileSet(),
		[]Type{},
	}
}
Exemple #4
0
// getPkg returns the package for a given id. If the package is
// not found, create the package and add it to the p.localPkgs
// and p.sharedPkgs maps. name is the (expected) name of the
// package. If name == "", the package name is expected to be
// set later via an import clause in the export data.
//
// id identifies a package, usually by a canonical package path like
// "encoding/json" but possibly by a non-canonical import path like
// "./json".
//
func (p *parser) getPkg(id, name string) *types.Package {
	// package unsafe is not in the packages maps - handle explicitly
	if id == "unsafe" {
		return types.Unsafe
	}

	pkg := p.localPkgs[id]
	if pkg == nil {
		// first import of id from this package
		pkg = p.sharedPkgs[id]
		if pkg == nil {
			// first import of id by this importer;
			// add (possibly unnamed) pkg to shared packages
			pkg = types.NewPackage(id, name)
			p.sharedPkgs[id] = pkg
		}
		// add (possibly unnamed) pkg to local packages
		if p.localPkgs == nil {
			p.localPkgs = make(map[string]*types.Package)
		}
		p.localPkgs[id] = pkg
	} else if name != "" {
		// package exists already and we have an expected package name;
		// make sure names match or set package name if necessary
		if pname := pkg.Name(); pname == "" {
			setName(pkg, name)
		} else if pname != name {
			p.errorf("%s package name mismatch: %s (given) vs %s (expected)", id, pname, name)
		}
	}
	return pkg
}
Exemple #5
0
func (p *importer) pkg() *types.Package {
	// if the package was seen before, i is its index (>= 0)
	i := p.int()
	if i >= 0 {
		return p.pkgList[i]
	}

	// otherwise, i is the package tag (< 0)
	if i != packageTag {
		panic(fmt.Sprintf("unexpected package tag %d", i))
	}

	// read package data
	name := p.string()
	path := p.string()

	// if the package was imported before, use that one; otherwise create a new one
	pkg := p.imports[path]
	if pkg == nil {
		pkg = types.NewPackage(path, name)
		p.imports[path] = pkg
	}
	p.pkgList = append(p.pkgList, pkg)

	return pkg
}
Exemple #6
0
func (imp *importer) newPackageInfo(path, dir string) *PackageInfo {
	pkg := types.NewPackage(path, "")
	info := &PackageInfo{
		Pkg: pkg,
		Info: types.Info{
			Types:      make(map[ast.Expr]types.TypeAndValue),
			Defs:       make(map[*ast.Ident]types.Object),
			Uses:       make(map[*ast.Ident]types.Object),
			Implicits:  make(map[ast.Node]types.Object),
			Scopes:     make(map[ast.Node]*types.Scope),
			Selections: make(map[*ast.SelectorExpr]*types.Selection),
		},
		errorFunc: imp.conf.TypeChecker.Error,
		dir:       dir,
	}

	// Copy the types.Config so we can vary it across PackageInfos.
	tc := imp.conf.TypeChecker
	tc.IgnoreFuncBodies = false
	if f := imp.conf.TypeCheckFuncBodies; f != nil {
		tc.IgnoreFuncBodies = !f(path)
	}
	tc.Importer = closure{imp, info}
	tc.Error = info.appendError // appendError wraps the user's Error function

	info.checker = types.NewChecker(&tc, imp.conf.fset(), pkg, &info.Info)
	imp.progMu.Lock()
	imp.prog.AllPackages[pkg] = info
	imp.progMu.Unlock()
	return info
}
// TestDevendorizeImportPaths checks if vendored
// import paths are devendorized correctly.
func TestDevendorizeImportPaths(t *testing.T) {
	i := imports.New("github.com/ernesto-jimenez/gogen/imports")
	pkg := types.NewPackage("github.com/ernesto-jimenez/gogen/vendor/github.com/stretchr/testify/mock", "mock")
	named := types.NewNamed(types.NewTypeName(token.Pos(0), pkg, "", &types.Array{}), &types.Array{}, nil)
	i.AddImportsFrom(named)
	require.Equal(t, map[string]string{"github.com/stretchr/testify/mock": "mock"}, i.Imports())
}
Exemple #8
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// getPkg returns the package for a given path. If the package is
// not found but we have a package name, create the package and
// add it to the p.imports map.
//
func (p *parser) getPkg(pkgpath, name string) *types.Package {
	// package unsafe is not in the imports map - handle explicitly
	if pkgpath == "unsafe" {
		return types.Unsafe
	}
	pkg := p.imports[pkgpath]
	if pkg == nil && name != "" {
		pkg = types.NewPackage(pkgpath, name)
		p.imports[pkgpath] = pkg
	}
	return pkg
}
Exemple #9
0
func loadExportData(pkgs []*build.Package, env []string, args ...string) ([]*types.Package, error) {
	// Compile the package. This will produce good errors if the package
	// doesn't typecheck for some reason, and is a necessary step to
	// building the final output anyway.
	paths := make([]string, len(pkgs))
	for i, p := range pkgs {
		paths[i] = p.ImportPath
	}
	if err := goInstall(paths, env, args...); err != nil {
		return nil, err
	}

	goos, goarch := getenv(env, "GOOS"), getenv(env, "GOARCH")

	// Assemble a fake GOPATH and trick go/importer into using it.
	// Ideally the importer package would let us provide this to
	// it somehow, but this works with what's in Go 1.5 today and
	// gives us access to the gcimporter package without us having
	// to make a copy of it.
	fakegopath := filepath.Join(tmpdir, "fakegopath")
	if err := removeAll(fakegopath); err != nil {
		return nil, err
	}
	if err := mkdir(filepath.Join(fakegopath, "pkg")); err != nil {
		return nil, err
	}
	typePkgs := make([]*types.Package, len(pkgs))
	imp := importer.Default()
	for i, p := range pkgs {
		importPath := p.ImportPath
		src := filepath.Join(pkgdir(env), importPath+".a")
		dst := filepath.Join(fakegopath, "pkg/"+goos+"_"+goarch+"/"+importPath+".a")
		if err := copyFile(dst, src); err != nil {
			return nil, err
		}
		if buildN {
			typePkgs[i] = types.NewPackage(importPath, path.Base(importPath))
			continue
		}
		oldDefault := build.Default
		build.Default = ctx // copy
		build.Default.GOARCH = goarch
		build.Default.GOPATH = fakegopath
		p, err := imp.Import(importPath)
		build.Default = oldDefault
		if err != nil {
			return nil, err
		}
		typePkgs[i] = p
	}
	return typePkgs, nil
}
Exemple #10
0
func TestBuildPackage_MissingImport(t *testing.T) {
	fset := token.NewFileSet()
	f, err := parser.ParseFile(fset, "bad.go", `package bad; import "missing"`, 0)
	if err != nil {
		t.Fatal(err)
	}

	pkg := types.NewPackage("bad", "")
	ssapkg, _, err := ssautil.BuildPackage(new(types.Config), fset, pkg, []*ast.File{f}, 0)
	if err == nil || ssapkg != nil {
		t.Fatal("BuildPackage succeeded unexpectedly")
	}
}
func TestSetName(t *testing.T) {
	pkg := types.NewPackage("path", "foo")
	scope := pkg.Scope()

	// verify setName
	setName(pkg, "bar")
	if name := pkg.Name(); name != "bar" {
		t.Fatalf(`got package name %q; want "bar"`, name)
	}

	// verify no other fields are changed
	if pkg.Path() != "path" || pkg.Scope() != scope || pkg.Complete() || pkg.Imports() != nil {
		t.Fatalf("setName changed other fields")
	}
}
Exemple #12
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func (p *importer) pkg() *types.Package {
	// if the package was seen before, i is its index (>= 0)
	i := p.tagOrIndex()
	if i >= 0 {
		return p.pkgList[i]
	}

	// otherwise, i is the package tag (< 0)
	if i != packageTag {
		panic(fmt.Sprintf("unexpected package tag %d", i))
	}

	// read package data
	name := p.string()
	path := p.string()

	// we should never see an empty package name
	if name == "" {
		panic("empty package name in import")
	}

	// an empty path denotes the package we are currently importing;
	// it must be the first package we see
	if (path == "") != (len(p.pkgList) == 0) {
		panic(fmt.Sprintf("package path %q for pkg index %d", path, len(p.pkgList)))
	}

	// if the package was imported before, use that one; otherwise create a new one
	if path == "" {
		path = p.path
	}
	pkg := p.imports[path]
	if pkg == nil {
		pkg = types.NewPackage(path, name)
		p.imports[path] = pkg
	} else if pkg.Name() != name {
		panic(fmt.Sprintf("conflicting names %s and %s for package %q", pkg.Name(), name, path))
	}
	p.pkgList = append(p.pkgList, pkg)

	return pkg
}
Exemple #13
0
func TestBuildPackage(t *testing.T) {
	// There is a more substantial test of BuildPackage and the
	// SSA program it builds in ../ssa/builder_test.go.

	fset := token.NewFileSet()
	f, err := parser.ParseFile(fset, "hello.go", hello, 0)
	if err != nil {
		t.Fatal(err)
	}

	pkg := types.NewPackage("hello", "")
	ssapkg, _, err := ssautil.BuildPackage(&types.Config{Importer: importer.Default()}, fset, pkg, []*ast.File{f}, 0)
	if err != nil {
		t.Fatal(err)
	}
	if pkg.Name() != "main" {
		t.Errorf("pkg.Name() = %s, want main", pkg.Name())
	}
	if ssapkg.Func("main") == nil {
		ssapkg.WriteTo(os.Stderr)
		t.Errorf("ssapkg has no main function")
	}
}
Exemple #14
0
// getPkg returns the package for a given id. If the package is
// not found but we have a package name, create the package and
// add it to the p.localPkgs and p.sharedPkgs maps.
//
// id identifies a package, usually by a canonical package path like
// "encoding/json" but possibly by a non-canonical import path like
// "./json".
//
func (p *parser) getPkg(id, name string) *types.Package {
	// package unsafe is not in the packages maps - handle explicitly
	if id == "unsafe" {
		return types.Unsafe
	}

	pkg := p.localPkgs[id]
	if pkg == nil && name != "" {
		// first import of id from this package
		pkg = p.sharedPkgs[id]
		if pkg == nil {
			// first import of id by this importer
			pkg = types.NewPackage(id, name)
			p.sharedPkgs[id] = pkg
		}

		if p.localPkgs == nil {
			p.localPkgs = make(map[string]*types.Package)
		}
		p.localPkgs[id] = pkg
	}
	return pkg
}
Exemple #15
0
	"go/types"
	"reflect"
	"unsafe"

	"golang.org/x/tools/go/ssa"
)

type opaqueType struct {
	types.Type
	name string
}

func (t *opaqueType) String() string { return t.name }

// A bogus "reflect" type-checker package.  Shared across interpreters.
var reflectTypesPackage = types.NewPackage("reflect", "reflect")

// rtype is the concrete type the interpreter uses to implement the
// reflect.Type interface.
//
// type rtype <opaque>
var rtypeType = makeNamedType("rtype", &opaqueType{nil, "rtype"})

// error is an (interpreted) named type whose underlying type is string.
// The interpreter uses it for all implementations of the built-in error
// interface that it creates.
// We put it in the "reflect" package for expedience.
//
// type error string
var errorType = makeNamedType("error", &opaqueType{nil, "error"})
// BImportData imports a package from the serialized package data
// and returns the number of bytes consumed and a reference to the package.
// If data is obviously malformed, an error is returned but in
// general it is not recommended to call BImportData on untrusted data.
func BImportData(imports map[string]*types.Package, data []byte, path string) (int, *types.Package, error) {
	p := importer{
		imports: imports,
		data:    data,
	}
	p.buf = p.bufarray[:]

	// read low-level encoding format
	switch format := p.byte(); format {
	case 'c':
		// compact format - nothing to do
	case 'd':
		p.debugFormat = true
	default:
		return p.read, nil, fmt.Errorf("invalid encoding format in export data: got %q; want 'c' or 'd'", format)
	}

	// --- generic export data ---

	if v := p.string(); v != "v0" {
		return p.read, nil, fmt.Errorf("unknown version: %s", v)
	}

	// populate typList with predeclared "known" types
	p.typList = append(p.typList, predeclared...)

	// read package data
	// TODO(gri) clean this up
	i := p.tagOrIndex()
	if i != packageTag {
		panic(fmt.Sprintf("package tag expected, got %d", i))
	}
	name := p.string()
	if s := p.string(); s != "" {
		panic(fmt.Sprintf("empty path expected, got %s", s))
	}
	pkg := p.imports[path]
	if pkg == nil {
		pkg = types.NewPackage(path, name)
		p.imports[path] = pkg
	}
	p.pkgList = append(p.pkgList, pkg)

	if debug && p.pkgList[0] != pkg {
		panic("imported packaged not found in pkgList[0]")
	}

	// read compiler-specific flags
	p.string() // discard

	// read consts
	for i := p.int(); i > 0; i-- {
		name := p.string()
		typ := p.typ(nil)
		val := p.value()
		p.declare(types.NewConst(token.NoPos, pkg, name, typ, val))
	}

	// read vars
	for i := p.int(); i > 0; i-- {
		name := p.string()
		typ := p.typ(nil)
		p.declare(types.NewVar(token.NoPos, pkg, name, typ))
	}

	// read funcs
	for i := p.int(); i > 0; i-- {
		name := p.string()
		sig := p.typ(nil).(*types.Signature)
		p.int() // read and discard index of inlined function body
		p.declare(types.NewFunc(token.NoPos, pkg, name, sig))
	}

	// read types
	for i := p.int(); i > 0; i-- {
		// name is parsed as part of named type and the
		// type object is added to scope via respective
		// named type
		_ = p.typ(nil).(*types.Named)
	}

	// ignore compiler-specific import data

	// complete interfaces
	for _, typ := range p.typList {
		if it, ok := typ.(*types.Interface); ok {
			it.Complete()
		}
	}

	// record all referenced packages as imports
	list := append(([]*types.Package)(nil), p.pkgList[1:]...)
	sort.Sort(byPath(list))
	pkg.SetImports(list)

	// package was imported completely and without errors
	pkg.MarkComplete()

	return p.read, pkg, nil
}
Exemple #17
0
// CreateTestMainPackage creates and returns a synthetic "main"
// package that runs all the tests of the supplied packages, similar
// to the one that would be created by the 'go test' tool.
//
// It returns nil if the program contains no tests.
//
func (prog *Program) CreateTestMainPackage(pkgs ...*Package) *Package {
	pkgs, tests, benchmarks, examples := FindTests(pkgs)
	if len(pkgs) == 0 {
		return nil
	}

	testmain := &Package{
		Prog:    prog,
		Members: make(map[string]Member),
		values:  make(map[types.Object]Value),
		Pkg:     types.NewPackage("test$main", "main"),
	}

	// Build package's init function.
	init := &Function{
		name:      "init",
		Signature: new(types.Signature),
		Synthetic: "package initializer",
		Pkg:       testmain,
		Prog:      prog,
	}
	init.startBody()

	if testMainStartBodyHook != nil {
		testMainStartBodyHook(init)
	}

	// Initialize packages to test.
	var pkgpaths []string
	for _, pkg := range pkgs {
		var v Call
		v.Call.Value = pkg.init
		v.setType(types.NewTuple())
		init.emit(&v)

		pkgpaths = append(pkgpaths, pkg.Pkg.Path())
	}
	sort.Strings(pkgpaths)
	init.emit(new(Return))
	init.finishBody()
	testmain.init = init
	testmain.Pkg.MarkComplete()
	testmain.Members[init.name] = init

	// For debugging convenience, define an unexported const
	// that enumerates the packages.
	packagesConst := types.NewConst(token.NoPos, testmain.Pkg, "packages", tString,
		exact.MakeString(strings.Join(pkgpaths, " ")))
	memberFromObject(testmain, packagesConst, nil)

	// Create main *types.Func and *ssa.Function
	mainFunc := types.NewFunc(token.NoPos, testmain.Pkg, "main", new(types.Signature))
	memberFromObject(testmain, mainFunc, nil)
	main := testmain.Func("main")
	main.Synthetic = "test main function"

	main.startBody()

	if testMainStartBodyHook != nil {
		testMainStartBodyHook(main)
	}

	if testingPkg := prog.ImportedPackage("testing"); testingPkg != nil {
		testingMain := testingPkg.Func("Main")
		testingMainParams := testingMain.Signature.Params()

		// The generated code is as if compiled from this:
		//
		// func main() {
		//      match      := func(_, _ string) (bool, error) { return true, nil }
		//      tests      := []testing.InternalTest{{"TestFoo", TestFoo}, ...}
		//      benchmarks := []testing.InternalBenchmark{...}
		//      examples   := []testing.InternalExample{...}
		// 	testing.Main(match, tests, benchmarks, examples)
		// }

		matcher := &Function{
			name:      "matcher",
			Signature: testingMainParams.At(0).Type().(*types.Signature),
			Synthetic: "test matcher predicate",
			parent:    main,
			Pkg:       testmain,
			Prog:      prog,
		}
		main.AnonFuncs = append(main.AnonFuncs, matcher)
		matcher.startBody()
		matcher.emit(&Return{Results: []Value{vTrue, nilConst(types.Universe.Lookup("error").Type())}})
		matcher.finishBody()

		// Emit call: testing.Main(matcher, tests, benchmarks, examples).
		var c Call
		c.Call.Value = testingMain
		c.Call.Args = []Value{
			matcher,
			testMainSlice(main, tests, testingMainParams.At(1).Type()),
			testMainSlice(main, benchmarks, testingMainParams.At(2).Type()),
			testMainSlice(main, examples, testingMainParams.At(3).Type()),
		}
		emitTailCall(main, &c)
	} else {
		// The program does not import "testing", but FindTests
		// returned non-nil, which must mean there were Examples
		// but no Tests or Benchmarks.
		// We'll simply call them from testmain.main; this will
		// ensure they don't panic, but will not check any
		// "Output:" comments.
		for _, eg := range examples {
			var c Call
			c.Call.Value = eg
			c.setType(types.NewTuple())
			main.emit(&c)
		}
		main.emit(&Return{})
		main.currentBlock = nil
	}

	main.finishBody()

	testmain.Members["main"] = main

	if prog.mode&PrintPackages != 0 {
		printMu.Lock()
		testmain.WriteTo(os.Stdout)
		printMu.Unlock()
	}

	if prog.mode&SanityCheckFunctions != 0 {
		sanityCheckPackage(testmain)
	}

	prog.packages[testmain.Pkg] = testmain

	return testmain
}
Exemple #18
0
// CreateTestMainPackage creates and returns a synthetic "testmain"
// package for the specified package if it defines tests, benchmarks or
// executable examples, or nil otherwise.  The new package is named
// "main" and provides a function named "main" that runs the tests,
// similar to the one that would be created by the 'go test' tool.
//
// Subsequent calls to prog.AllPackages include the new package.
// The package pkg must belong to the program prog.
func (prog *Program) CreateTestMainPackage(pkg *Package) *Package {
	if pkg.Prog != prog {
		log.Fatal("Package does not belong to Program")
	}

	tests, benchmarks, examples, testMainFunc := FindTests(pkg)

	if testMainFunc == nil && tests == nil && benchmarks == nil && examples == nil {
		return nil
	}

	testmain := &Package{
		Prog:    prog,
		Members: make(map[string]Member),
		values:  make(map[types.Object]Value),
		Pkg:     types.NewPackage(pkg.Pkg.Path()+"$testmain", "main"),
	}

	// Build package's init function.
	init := &Function{
		name:      "init",
		Signature: new(types.Signature),
		Synthetic: "package initializer",
		Pkg:       testmain,
		Prog:      prog,
	}
	init.startBody()

	if testMainStartBodyHook != nil {
		testMainStartBodyHook(init)
	}

	// Initialize package under test.
	var v Call
	v.Call.Value = pkg.init
	v.setType(types.NewTuple())
	init.emit(&v)
	init.emit(new(Return))
	init.finishBody()
	testmain.init = init
	testmain.Pkg.MarkComplete()
	testmain.Members[init.name] = init

	// Create main *types.Func and *Function
	mainFunc := types.NewFunc(token.NoPos, testmain.Pkg, "main", new(types.Signature))
	memberFromObject(testmain, mainFunc, nil)
	main := testmain.Func("main")
	main.Synthetic = "test main function"

	main.startBody()

	if testMainStartBodyHook != nil {
		testMainStartBodyHook(main)
	}

	if testingPkg := prog.ImportedPackage("testing"); testingPkg != nil {
		testingMain := testingPkg.Func("Main")
		testingMainParams := testingMain.Signature.Params()

		// The generated code is as if compiled from this:
		//
		// func main() {
		//      match      := func(_, _ string) (bool, error) { return true, nil }
		//      tests      := []testing.InternalTest{{"TestFoo", TestFoo}, ...}
		//      benchmarks := []testing.InternalBenchmark{...}
		//      examples   := []testing.InternalExample{...}
		//	if TestMain is defined {
		// 		m := testing.MainStart(match, tests, benchmarks, examples)
		// 		return TestMain(m)
		// 	} else {
		// 		return testing.Main(match, tests, benchmarks, examples)
		// 	}
		// }

		matcher := &Function{
			name:      "matcher",
			Signature: testingMainParams.At(0).Type().(*types.Signature),
			Synthetic: "test matcher predicate",
			parent:    main,
			Pkg:       testmain,
			Prog:      prog,
		}
		main.AnonFuncs = append(main.AnonFuncs, matcher)
		matcher.startBody()
		matcher.emit(&Return{Results: []Value{vTrue, nilConst(types.Universe.Lookup("error").Type())}})
		matcher.finishBody()

		var c Call
		c.Call.Args = []Value{
			matcher,
			testMainSlice(main, tests, testingMainParams.At(1).Type()),
			testMainSlice(main, benchmarks, testingMainParams.At(2).Type()),
			testMainSlice(main, examples, testingMainParams.At(3).Type()),
		}
		if testMainFunc != nil {
			// Emit: m := testing.MainStart(matcher, tests, benchmarks, examples).
			// (Main and MainStart have the same parameters.)
			mainStart := testingPkg.Func("MainStart")
			c.Call.Value = mainStart
			c.setType(mainStart.Signature.Results().At(0).Type()) // *testing.M
			m := main.emit(&c)

			// Emit: return TestMain(m)
			var c2 Call
			c2.Call.Value = testMainFunc
			c2.Call.Args = []Value{m}
			emitTailCall(main, &c2)
		} else {
			// Emit: return testing.Main(matcher, tests, benchmarks, examples)
			c.Call.Value = testingMain
			emitTailCall(main, &c)
		}
	} else {
		// The program does not import "testing", but FindTests
		// returned non-nil, which must mean there were Examples
		// but no Test, Benchmark, or TestMain functions.

		// We'll simply call them from testmain.main; this will
		// ensure they don't panic, but will not check any
		// "Output:" comments.
		// (We should not execute an Example that has no
		// "Output:" comment, but it's impossible to tell here.)
		for _, eg := range examples {
			var c Call
			c.Call.Value = eg
			c.setType(types.NewTuple())
			main.emit(&c)
		}
		main.emit(&Return{})
		main.currentBlock = nil
	}

	main.finishBody()

	testmain.Members["main"] = main

	if prog.mode&PrintPackages != 0 {
		printMu.Lock()
		testmain.WriteTo(os.Stdout)
		printMu.Unlock()
	}

	if prog.mode&SanityCheckFunctions != 0 {
		sanityCheckPackage(testmain)
	}

	prog.packages[testmain.Pkg] = testmain

	return testmain
}
// This program demonstrates how to run the SSA builder on a single
// package of one or more already-parsed files.  Its dependencies are
// loaded from compiler export data.  This is what you'd typically use
// for a compiler; it does not depend on golang.org/x/tools/go/loader.
//
// It shows the printed representation of packages, functions, and
// instructions.  Within the function listing, the name of each
// BasicBlock such as ".0.entry" is printed left-aligned, followed by
// the block's Instructions.
//
// For each instruction that defines an SSA virtual register
// (i.e. implements Value), the type of that value is shown in the
// right column.
//
// Build and run the ssadump.go program if you want a standalone tool
// with similar functionality. It is located at
// golang.org/x/tools/cmd/ssadump.
//
func ExampleBuildPackage() {
	// Parse the source files.
	fset := token.NewFileSet()
	f, err := parser.ParseFile(fset, "hello.go", hello, parser.ParseComments)
	if err != nil {
		fmt.Print(err) // parse error
		return
	}
	files := []*ast.File{f}

	// Create the type-checker's package.
	pkg := types.NewPackage("hello", "")

	// Type-check the package, load dependencies.
	// Create and build the SSA program.
	hello, _, err := ssautil.BuildPackage(
		&types.Config{Importer: importer.Default()}, fset, pkg, files, ssa.SanityCheckFunctions)
	if err != nil {
		fmt.Print(err) // type error in some package
		return
	}

	// Print out the package.
	hello.WriteTo(os.Stdout)

	// Print out the package-level functions.
	hello.Func("init").WriteTo(os.Stdout)
	hello.Func("main").WriteTo(os.Stdout)

	// Output:
	//
	// package hello:
	//   func  init       func()
	//   var   init$guard bool
	//   func  main       func()
	//   const message    message = "Hello, World!":untyped string
	//
	// # Name: hello.init
	// # Package: hello
	// # Synthetic: package initializer
	// func init():
	// 0:                                                                entry P:0 S:2
	// 	t0 = *init$guard                                                   bool
	// 	if t0 goto 2 else 1
	// 1:                                                           init.start P:1 S:1
	// 	*init$guard = true:bool
	// 	t1 = fmt.init()                                                      ()
	// 	jump 2
	// 2:                                                            init.done P:2 S:0
	// 	return
	//
	// # Name: hello.main
	// # Package: hello
	// # Location: hello.go:8:6
	// func main():
	// 0:                                                                entry P:0 S:0
	// 	t0 = new [1]interface{} (varargs)                       *[1]interface{}
	// 	t1 = &t0[0:int]                                            *interface{}
	// 	t2 = make interface{} <- string ("Hello, World!":string)    interface{}
	// 	*t1 = t2
	// 	t3 = slice t0[:]                                          []interface{}
	// 	t4 = fmt.Println(t3...)                              (n int, err error)
	// 	return
}
// TestRuntimeTypes tests that (*Program).RuntimeTypes() includes all necessary types.
func TestRuntimeTypes(t *testing.T) {
	tests := []struct {
		input string
		want  []string
	}{
		// An exported package-level type is needed.
		{`package A; type T struct{}; func (T) f() {}`,
			[]string{"*p.T", "p.T"},
		},
		// An unexported package-level type is not needed.
		{`package B; type t struct{}; func (t) f() {}`,
			nil,
		},
		// Subcomponents of type of exported package-level var are needed.
		{`package C; import "bytes"; var V struct {*bytes.Buffer}`,
			[]string{"*bytes.Buffer", "*struct{*bytes.Buffer}", "struct{*bytes.Buffer}"},
		},
		// Subcomponents of type of unexported package-level var are not needed.
		{`package D; import "bytes"; var v struct {*bytes.Buffer}`,
			nil,
		},
		// Subcomponents of type of exported package-level function are needed.
		{`package E; import "bytes"; func F(struct {*bytes.Buffer}) {}`,
			[]string{"*bytes.Buffer", "struct{*bytes.Buffer}"},
		},
		// Subcomponents of type of unexported package-level function are not needed.
		{`package F; import "bytes"; func f(struct {*bytes.Buffer}) {}`,
			nil,
		},
		// Subcomponents of type of exported method of uninstantiated unexported type are not needed.
		{`package G; import "bytes"; type x struct{}; func (x) G(struct {*bytes.Buffer}) {}; var v x`,
			nil,
		},
		// ...unless used by MakeInterface.
		{`package G2; import "bytes"; type x struct{}; func (x) G(struct {*bytes.Buffer}) {}; var v interface{} = x{}`,
			[]string{"*bytes.Buffer", "*p.x", "p.x", "struct{*bytes.Buffer}"},
		},
		// Subcomponents of type of unexported method are not needed.
		{`package I; import "bytes"; type X struct{}; func (X) G(struct {*bytes.Buffer}) {}`,
			[]string{"*bytes.Buffer", "*p.X", "p.X", "struct{*bytes.Buffer}"},
		},
		// Local types aren't needed.
		{`package J; import "bytes"; func f() { type T struct {*bytes.Buffer}; var t T; _ = t }`,
			nil,
		},
		// ...unless used by MakeInterface.
		{`package K; import "bytes"; func f() { type T struct {*bytes.Buffer}; _ = interface{}(T{}) }`,
			[]string{"*bytes.Buffer", "*p.T", "p.T"},
		},
		// Types used as operand of MakeInterface are needed.
		{`package L; import "bytes"; func f() { _ = interface{}(struct{*bytes.Buffer}{}) }`,
			[]string{"*bytes.Buffer", "struct{*bytes.Buffer}"},
		},
		// MakeInterface is optimized away when storing to a blank.
		{`package M; import "bytes"; var _ interface{} = struct{*bytes.Buffer}{}`,
			nil,
		},
	}
	for _, test := range tests {
		// Parse the file.
		fset := token.NewFileSet()
		f, err := parser.ParseFile(fset, "input.go", test.input, 0)
		if err != nil {
			t.Errorf("test %q: %s", test.input[:15], err)
			continue
		}

		// Create a single-file main package.
		// Load dependencies from gc binary export data.
		ssapkg, _, err := ssautil.BuildPackage(&types.Config{Importer: importer.Default()}, fset,
			types.NewPackage("p", ""), []*ast.File{f}, ssa.SanityCheckFunctions)
		if err != nil {
			t.Errorf("test %q: %s", test.input[:15], err)
			continue
		}

		var typstrs []string
		for _, T := range ssapkg.Prog.RuntimeTypes() {
			typstrs = append(typstrs, T.String())
		}
		sort.Strings(typstrs)

		if !reflect.DeepEqual(typstrs, test.want) {
			t.Errorf("test 'package %s': got %q, want %q",
				f.Name.Name, typstrs, test.want)
		}
	}
}
// Tests that programs partially loaded from gc object files contain
// functions with no code for the external portions, but are otherwise ok.
func TestBuildPackage(t *testing.T) {
	input := `
package main

import (
	"bytes"
	"io"
	"testing"
)

func main() {
        var t testing.T
	t.Parallel()    // static call to external declared method
        t.Fail()        // static call to promoted external declared method
        testing.Short() // static call to external package-level function

        var w io.Writer = new(bytes.Buffer)
        w.Write(nil)    // interface invoke of external declared method
}
`

	// Parse the file.
	fset := token.NewFileSet()
	f, err := parser.ParseFile(fset, "input.go", input, 0)
	if err != nil {
		t.Error(err)
		return
	}

	// Build an SSA program from the parsed file.
	// Load its dependencies from gc binary export data.
	mainPkg, _, err := ssautil.BuildPackage(&types.Config{Importer: importer.Default()}, fset,
		types.NewPackage("main", ""), []*ast.File{f}, ssa.SanityCheckFunctions)
	if err != nil {
		t.Error(err)
		return
	}

	// The main package, its direct and indirect dependencies are loaded.
	deps := []string{
		// directly imported dependencies:
		"bytes", "io", "testing",
		// indirect dependencies mentioned by
		// the direct imports' export data
		"sync", "unicode", "time",
	}

	prog := mainPkg.Prog
	all := prog.AllPackages()
	if len(all) <= len(deps) {
		t.Errorf("unexpected set of loaded packages: %q", all)
	}
	for _, path := range deps {
		pkg := prog.ImportedPackage(path)
		if pkg == nil {
			t.Errorf("package not loaded: %q", path)
			continue
		}

		// External packages should have no function bodies (except for wrappers).
		isExt := pkg != mainPkg

		// init()
		if isExt && !isEmpty(pkg.Func("init")) {
			t.Errorf("external package %s has non-empty init", pkg)
		} else if !isExt && isEmpty(pkg.Func("init")) {
			t.Errorf("main package %s has empty init", pkg)
		}

		for _, mem := range pkg.Members {
			switch mem := mem.(type) {
			case *ssa.Function:
				// Functions at package level.
				if isExt && !isEmpty(mem) {
					t.Errorf("external function %s is non-empty", mem)
				} else if !isExt && isEmpty(mem) {
					t.Errorf("function %s is empty", mem)
				}

			case *ssa.Type:
				// Methods of named types T.
				// (In this test, all exported methods belong to *T not T.)
				if !isExt {
					t.Fatalf("unexpected name type in main package: %s", mem)
				}
				mset := prog.MethodSets.MethodSet(types.NewPointer(mem.Type()))
				for i, n := 0, mset.Len(); i < n; i++ {
					m := prog.MethodValue(mset.At(i))
					// For external types, only synthetic wrappers have code.
					expExt := !strings.Contains(m.Synthetic, "wrapper")
					if expExt && !isEmpty(m) {
						t.Errorf("external method %s is non-empty: %s",
							m, m.Synthetic)
					} else if !expExt && isEmpty(m) {
						t.Errorf("method function %s is empty: %s",
							m, m.Synthetic)
					}
				}
			}
		}
	}

	expectedCallee := []string{
		"(*testing.T).Parallel",
		"(*testing.common).Fail",
		"testing.Short",
		"N/A",
	}
	callNum := 0
	for _, b := range mainPkg.Func("main").Blocks {
		for _, instr := range b.Instrs {
			switch instr := instr.(type) {
			case ssa.CallInstruction:
				call := instr.Common()
				if want := expectedCallee[callNum]; want != "N/A" {
					got := call.StaticCallee().String()
					if want != got {
						t.Errorf("call #%d from main.main: got callee %s, want %s",
							callNum, got, want)
					}
				}
				callNum++
			}
		}
	}
	if callNum != 4 {
		t.Errorf("in main.main: got %d calls, want %d", callNum, 4)
	}
}