stdlib_test.go

     1  // Copyright 2013 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // This file tests types2.Check by using it to
     6  // typecheck the standard library and tests.
     7  
     8  package types2_test
     9  
    10  import (
    11  	"bytes"
    12  	"cmd/compile/internal/syntax"
    13  	"errors"
    14  	"fmt"
    15  	"go/build"
    16  	"internal/testenv"
    17  	"os"
    18  	"path/filepath"
    19  	"runtime"
    20  	"strings"
    21  	"sync"
    22  	"testing"
    23  	"time"
    24  
    25  	. "cmd/compile/internal/types2"
    26  )
    27  
    28  var stdLibImporter = defaultImporter()
    29  
    30  func TestStdlib(t *testing.T) {
    31  	if testing.Short() {
    32  		t.Skip("skipping in short mode")
    33  	}
    34  
    35  	testenv.MustHaveGoBuild(t)
    36  
    37  	// Collect non-test files.
    38  	dirFiles := make(map[string][]string)
    39  	root := filepath.Join(testenv.GOROOT(t), "src")
    40  	walkPkgDirs(root, func(dir string, filenames []string) {
    41  		dirFiles[dir] = filenames
    42  	}, t.Error)
    43  
    44  	c := &stdlibChecker{
    45  		dirFiles: dirFiles,
    46  		pkgs:     make(map[string]*futurePackage),
    47  	}
    48  
    49  	start := time.Now()
    50  
    51  	// Though we read files while parsing, type-checking is otherwise CPU bound.
    52  	//
    53  	// This doesn't achieve great CPU utilization as many packages may block
    54  	// waiting for a common import, but in combination with the non-deterministic
    55  	// map iteration below this should provide decent coverage of concurrent
    56  	// type-checking (see golang/go#47729).
    57  	cpulimit := make(chan struct{}, runtime.GOMAXPROCS(0))
    58  	var wg sync.WaitGroup
    59  
    60  	for dir := range dirFiles {
    61  		dir := dir
    62  
    63  		cpulimit <- struct{}{}
    64  		wg.Add(1)
    65  		go func() {
    66  			defer func() {
    67  				wg.Done()
    68  				<-cpulimit
    69  			}()
    70  
    71  			_, err := c.getDirPackage(dir)
    72  			if err != nil {
    73  				t.Errorf("error checking %s: %v", dir, err)
    74  			}
    75  		}()
    76  	}
    77  
    78  	wg.Wait()
    79  
    80  	if testing.Verbose() {
    81  		fmt.Println(len(dirFiles), "packages typechecked in", time.Since(start))
    82  	}
    83  }
    84  
    85  // stdlibChecker implements concurrent type-checking of the packages defined by
    86  // dirFiles, which must define a closed set of packages (such as GOROOT/src).
    87  type stdlibChecker struct {
    88  	dirFiles map[string][]string // non-test files per directory; must be pre-populated
    89  
    90  	mu   sync.Mutex
    91  	pkgs map[string]*futurePackage // future cache of type-checking results
    92  }
    93  
    94  // A futurePackage is a future result of type-checking.
    95  type futurePackage struct {
    96  	done chan struct{} // guards pkg and err
    97  	pkg  *Package
    98  	err  error
    99  }
   100  
   101  func (c *stdlibChecker) Import(path string) (*Package, error) {
   102  	panic("unimplemented: use ImportFrom")
   103  }
   104  
   105  func (c *stdlibChecker) ImportFrom(path, dir string, _ ImportMode) (*Package, error) {
   106  	if path == "unsafe" {
   107  		// unsafe cannot be type checked normally.
   108  		return Unsafe, nil
   109  	}
   110  
   111  	p, err := build.Default.Import(path, dir, build.FindOnly)
   112  	if err != nil {
   113  		return nil, err
   114  	}
   115  
   116  	pkg, err := c.getDirPackage(p.Dir)
   117  	if pkg != nil {
   118  		// As long as pkg is non-nil, avoid redundant errors related to failed
   119  		// imports. TestStdlib will collect errors once for each package.
   120  		return pkg, nil
   121  	}
   122  	return nil, err
   123  }
   124  
   125  // getDirPackage gets the package defined in dir from the future cache.
   126  //
   127  // If this is the first goroutine requesting the package, getDirPackage
   128  // type-checks.
   129  func (c *stdlibChecker) getDirPackage(dir string) (*Package, error) {
   130  	c.mu.Lock()
   131  	fut, ok := c.pkgs[dir]
   132  	if !ok {
   133  		// First request for this package dir; type check.
   134  		fut = &futurePackage{
   135  			done: make(chan struct{}),
   136  		}
   137  		c.pkgs[dir] = fut
   138  		files, ok := c.dirFiles[dir]
   139  		c.mu.Unlock()
   140  		if !ok {
   141  			fut.err = fmt.Errorf("no files for %s", dir)
   142  		} else {
   143  			// Using dir as the package path here may be inconsistent with the behavior
   144  			// of a normal importer, but is sufficient as dir is by construction unique
   145  			// to this package.
   146  			fut.pkg, fut.err = typecheckFiles(dir, files, c)
   147  		}
   148  		close(fut.done)
   149  	} else {
   150  		// Otherwise, await the result.
   151  		c.mu.Unlock()
   152  		<-fut.done
   153  	}
   154  	return fut.pkg, fut.err
   155  }
   156  
   157  // firstComment returns the contents of the first non-empty comment in
   158  // the given file, "skip", or the empty string. No matter the present
   159  // comments, if any of them contains a build tag, the result is always
   160  // "skip". Only comments within the first 4K of the file are considered.
   161  // TODO(gri) should only read until we see "package" token.
   162  func firstComment(filename string) (first string) {
   163  	f, err := os.Open(filename)
   164  	if err != nil {
   165  		return ""
   166  	}
   167  	defer f.Close()
   168  
   169  	// read at most 4KB
   170  	var buf [4 << 10]byte
   171  	n, _ := f.Read(buf[:])
   172  	src := bytes.NewBuffer(buf[:n])
   173  
   174  	// TODO(gri) we need a better way to terminate CommentsDo
   175  	defer func() {
   176  		if p := recover(); p != nil {
   177  			if s, ok := p.(string); ok {
   178  				first = s
   179  			}
   180  		}
   181  	}()
   182  
   183  	syntax.CommentsDo(src, func(_, _ uint, text string) {
   184  		if text[0] != '/' {
   185  			return // not a comment
   186  		}
   187  
   188  		// extract comment text
   189  		if text[1] == '*' {
   190  			text = text[:len(text)-2]
   191  		}
   192  		text = strings.TrimSpace(text[2:])
   193  
   194  		if strings.HasPrefix(text, "go:build ") {
   195  			panic("skip")
   196  		}
   197  		if first == "" {
   198  			first = text // text may be "" but that's ok
   199  		}
   200  		// continue as we may still see build tags
   201  	})
   202  
   203  	return
   204  }
   205  
   206  func testTestDir(t *testing.T, path string, ignore ...string) {
   207  	files, err := os.ReadDir(path)
   208  	if err != nil {
   209  		// cmd/distpack deletes GOROOT/test, so skip the test if it isn't present.
   210  		// cmd/distpack also requires GOROOT/VERSION to exist, so use that to
   211  		// suppress false-positive skips.
   212  		if _, err := os.Stat(filepath.Join(testenv.GOROOT(t), "test")); os.IsNotExist(err) {
   213  			if _, err := os.Stat(filepath.Join(testenv.GOROOT(t), "VERSION")); err == nil {
   214  				t.Skipf("skipping: GOROOT/test not present")
   215  			}
   216  		}
   217  		t.Fatal(err)
   218  	}
   219  
   220  	excluded := make(map[string]bool)
   221  	for _, filename := range ignore {
   222  		excluded[filename] = true
   223  	}
   224  
   225  	for _, f := range files {
   226  		// filter directory contents
   227  		if f.IsDir() || !strings.HasSuffix(f.Name(), ".go") || excluded[f.Name()] {
   228  			continue
   229  		}
   230  
   231  		// get per-file instructions
   232  		expectErrors := false
   233  		filename := filepath.Join(path, f.Name())
   234  		goVersion := ""
   235  		if comment := firstComment(filename); comment != "" {
   236  			if strings.Contains(comment, "-goexperiment") {
   237  				continue // ignore this file
   238  			}
   239  			fields := strings.Fields(comment)
   240  			switch fields[0] {
   241  			case "skip", "compiledir":
   242  				continue // ignore this file
   243  			case "errorcheck":
   244  				expectErrors = true
   245  				for _, arg := range fields[1:] {
   246  					if arg == "-0" || arg == "-+" || arg == "-std" {
   247  						// Marked explicitly as not expecting errors (-0),
   248  						// or marked as compiling runtime/stdlib, which is only done
   249  						// to trigger runtime/stdlib-only error output.
   250  						// In both cases, the code should typecheck.
   251  						expectErrors = false
   252  						break
   253  					}
   254  					const prefix = "-lang="
   255  					if strings.HasPrefix(arg, prefix) {
   256  						goVersion = arg[len(prefix):]
   257  					}
   258  				}
   259  			}
   260  		}
   261  
   262  		// parse and type-check file
   263  		if testing.Verbose() {
   264  			fmt.Println("\t", filename)
   265  		}
   266  		file, err := syntax.ParseFile(filename, nil, nil, 0)
   267  		if err == nil {
   268  			conf := Config{
   269  				GoVersion: goVersion,
   270  				Importer:  stdLibImporter,
   271  			}
   272  			_, err = conf.Check(filename, []*syntax.File{file}, nil)
   273  		}
   274  
   275  		if expectErrors {
   276  			if err == nil {
   277  				t.Errorf("expected errors but found none in %s", filename)
   278  			}
   279  		} else {
   280  			if err != nil {
   281  				t.Error(err)
   282  			}
   283  		}
   284  	}
   285  }
   286  
   287  func TestStdTest(t *testing.T) {
   288  	testenv.MustHaveGoBuild(t)
   289  
   290  	if testing.Short() && testenv.Builder() == "" {
   291  		t.Skip("skipping in short mode")
   292  	}
   293  
   294  	testTestDir(t, filepath.Join(testenv.GOROOT(t), "test"),
   295  		"cmplxdivide.go", // also needs file cmplxdivide1.go - ignore
   296  		"directive.go",   // tests compiler rejection of bad directive placement - ignore
   297  		"directive2.go",  // tests compiler rejection of bad directive placement - ignore
   298  		"embedfunc.go",   // tests //go:embed
   299  		"embedvers.go",   // tests //go:embed
   300  		"linkname2.go",   // types2 doesn't check validity of //go:xxx directives
   301  		"linkname3.go",   // types2 doesn't check validity of //go:xxx directives
   302  	)
   303  }
   304  
   305  func TestStdFixed(t *testing.T) {
   306  	testenv.MustHaveGoBuild(t)
   307  
   308  	if testing.Short() && testenv.Builder() == "" {
   309  		t.Skip("skipping in short mode")
   310  	}
   311  
   312  	testTestDir(t, filepath.Join(testenv.GOROOT(t), "test", "fixedbugs"),
   313  		"bug248.go", "bug302.go", "bug369.go", // complex test instructions - ignore
   314  		"bug398.go",      // types2 doesn't check for anonymous interface cycles (go.dev/issue/56103)
   315  		"issue6889.go",   // gc-specific test
   316  		"issue11362.go",  // canonical import path check
   317  		"issue16369.go",  // types2 handles this correctly - not an issue
   318  		"issue18459.go",  // types2 doesn't check validity of //go:xxx directives
   319  		"issue18882.go",  // types2 doesn't check validity of //go:xxx directives
   320  		"issue20529.go",  // types2 does not have constraints on stack size
   321  		"issue22200.go",  // types2 does not have constraints on stack size
   322  		"issue22200b.go", // types2 does not have constraints on stack size
   323  		"issue25507.go",  // types2 does not have constraints on stack size
   324  		"issue20780.go",  // types2 does not have constraints on stack size
   325  		"issue42058a.go", // types2 does not have constraints on channel element size
   326  		"issue42058b.go", // types2 does not have constraints on channel element size
   327  		"issue48097.go",  // go/types doesn't check validity of //go:xxx directives, and non-init bodyless function
   328  		"issue48230.go",  // go/types doesn't check validity of //go:xxx directives
   329  		"issue49767.go",  // go/types does not have constraints on channel element size
   330  		"issue49814.go",  // go/types does not have constraints on array size
   331  		"issue56103.go",  // anonymous interface cycles; will be a type checker error in 1.22
   332  		"issue52697.go",  // types2 does not have constraints on stack size
   333  
   334  		// These tests requires runtime/cgo.Incomplete, which is only available on some platforms.
   335  		// However, types2 does not know about build constraints.
   336  		"bug514.go",
   337  		"issue40954.go",
   338  		"issue42032.go",
   339  		"issue42076.go",
   340  		"issue46903.go",
   341  		"issue51733.go",
   342  		"notinheap2.go",
   343  		"notinheap3.go",
   344  	)
   345  }
   346  
   347  func TestStdKen(t *testing.T) {
   348  	testenv.MustHaveGoBuild(t)
   349  
   350  	testTestDir(t, filepath.Join(testenv.GOROOT(t), "test", "ken"))
   351  }
   352  
   353  // Package paths of excluded packages.
   354  var excluded = map[string]bool{
   355  	"builtin": true,
   356  
   357  	// go.dev/issue/46027: some imports are missing for this submodule.
   358  	"crypto/internal/edwards25519/field/_asm": true,
   359  	"crypto/internal/bigmod/_asm":             true,
   360  }
   361  
   362  // printPackageMu synchronizes the printing of type-checked package files in
   363  // the typecheckFiles function.
   364  //
   365  // Without synchronization, package files may be interleaved during concurrent
   366  // type-checking.
   367  var printPackageMu sync.Mutex
   368  
   369  // typecheckFiles typechecks the given package files.
   370  func typecheckFiles(path string, filenames []string, importer Importer) (*Package, error) {
   371  	// Parse package files.
   372  	var files []*syntax.File
   373  	for _, filename := range filenames {
   374  		var errs []error
   375  		errh := func(err error) { errs = append(errs, err) }
   376  		file, err := syntax.ParseFile(filename, errh, nil, 0)
   377  		if err != nil {
   378  			return nil, errors.Join(errs...)
   379  		}
   380  
   381  		files = append(files, file)
   382  	}
   383  
   384  	if testing.Verbose() {
   385  		printPackageMu.Lock()
   386  		fmt.Println("package", files[0].PkgName.Value)
   387  		for _, filename := range filenames {
   388  			fmt.Println("\t", filename)
   389  		}
   390  		printPackageMu.Unlock()
   391  	}
   392  
   393  	// Typecheck package files.
   394  	var errs []error
   395  	conf := Config{
   396  		Error: func(err error) {
   397  			errs = append(errs, err)
   398  		},
   399  		Importer:    importer,
   400  		EnableAlias: true,
   401  	}
   402  	info := Info{Uses: make(map[*syntax.Name]Object)}
   403  	pkg, _ := conf.Check(path, files, &info)
   404  	err := errors.Join(errs...)
   405  	if err != nil {
   406  		return pkg, err
   407  	}
   408  
   409  	// Perform checks of API invariants.
   410  
   411  	// All Objects have a package, except predeclared ones.
   412  	errorError := Universe.Lookup("error").Type().Underlying().(*Interface).ExplicitMethod(0) // (error).Error
   413  	for id, obj := range info.Uses {
   414  		predeclared := obj == Universe.Lookup(obj.Name()) || obj == errorError
   415  		if predeclared == (obj.Pkg() != nil) {
   416  			posn := id.Pos()
   417  			if predeclared {
   418  				return nil, fmt.Errorf("%s: predeclared object with package: %s", posn, obj)
   419  			} else {
   420  				return nil, fmt.Errorf("%s: user-defined object without package: %s", posn, obj)
   421  			}
   422  		}
   423  	}
   424  
   425  	return pkg, nil
   426  }
   427  
   428  // pkgFilenames returns the list of package filenames for the given directory.
   429  func pkgFilenames(dir string, includeTest bool) ([]string, error) {
   430  	ctxt := build.Default
   431  	ctxt.CgoEnabled = false
   432  	pkg, err := ctxt.ImportDir(dir, 0)
   433  	if err != nil {
   434  		if _, nogo := err.(*build.NoGoError); nogo {
   435  			return nil, nil // no *.go files, not an error
   436  		}
   437  		return nil, err
   438  	}
   439  	if excluded[pkg.ImportPath] {
   440  		return nil, nil
   441  	}
   442  	var filenames []string
   443  	for _, name := range pkg.GoFiles {
   444  		filenames = append(filenames, filepath.Join(pkg.Dir, name))
   445  	}
   446  	if includeTest {
   447  		for _, name := range pkg.TestGoFiles {
   448  			filenames = append(filenames, filepath.Join(pkg.Dir, name))
   449  		}
   450  	}
   451  	return filenames, nil
   452  }
   453  
   454  func walkPkgDirs(dir string, pkgh func(dir string, filenames []string), errh func(args ...interface{})) {
   455  	w := walker{pkgh, errh}
   456  	w.walk(dir)
   457  }
   458  
   459  type walker struct {
   460  	pkgh func(dir string, filenames []string)
   461  	errh func(args ...any)
   462  }
   463  
   464  func (w *walker) walk(dir string) {
   465  	files, err := os.ReadDir(dir)
   466  	if err != nil {
   467  		w.errh(err)
   468  		return
   469  	}
   470  
   471  	// apply pkgh to the files in directory dir
   472  
   473  	// Don't get test files as these packages are imported.
   474  	pkgFiles, err := pkgFilenames(dir, false)
   475  	if err != nil {
   476  		w.errh(err)
   477  		return
   478  	}
   479  	if pkgFiles != nil {
   480  		w.pkgh(dir, pkgFiles)
   481  	}
   482  
   483  	// traverse subdirectories, but don't walk into testdata
   484  	for _, f := range files {
   485  		if f.IsDir() && f.Name() != "testdata" {
   486  			w.walk(filepath.Join(dir, f.Name()))
   487  		}
   488  	}
   489  }
   490
View as plain text