check_test.go

     1  // Copyright 2011 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 implements a typechecker test harness. The packages specified
     6  // in tests are typechecked. Error messages reported by the typechecker are
     7  // compared against the errors expected in the test files.
     8  //
     9  // Expected errors are indicated in the test files by putting comments
    10  // of the form /* ERROR pattern */ or /* ERRORx pattern */ (or a similar
    11  // //-style line comment) immediately following the tokens where errors
    12  // are reported. There must be exactly one blank before and after the
    13  // ERROR/ERRORx indicator, and the pattern must be a properly quoted Go
    14  // string.
    15  //
    16  // The harness will verify that each ERROR pattern is a substring of the
    17  // error reported at that source position, and that each ERRORx pattern
    18  // is a regular expression matching the respective error.
    19  // Consecutive comments may be used to indicate multiple errors reported
    20  // at the same position.
    21  //
    22  // For instance, the following test source indicates that an "undeclared"
    23  // error should be reported for the undeclared variable x:
    24  //
    25  //	package p
    26  //	func f() {
    27  //		_ = x /* ERROR "undeclared" */ + 1
    28  //	}
    29  
    30  package types2_test
    31  
    32  import (
    33  	"bytes"
    34  	"cmd/compile/internal/syntax"
    35  	"flag"
    36  	"fmt"
    37  	"internal/buildcfg"
    38  	"internal/testenv"
    39  	"os"
    40  	"path/filepath"
    41  	"reflect"
    42  	"regexp"
    43  	"runtime"
    44  	"strconv"
    45  	"strings"
    46  	"testing"
    47  
    48  	. "cmd/compile/internal/types2"
    49  )
    50  
    51  var (
    52  	haltOnError  = flag.Bool("halt", false, "halt on error")
    53  	verifyErrors = flag.Bool("verify", false, "verify errors (rather than list them) in TestManual")
    54  )
    55  
    56  func parseFiles(t *testing.T, filenames []string, srcs [][]byte, mode syntax.Mode) ([]*syntax.File, []error) {
    57  	var files []*syntax.File
    58  	var errlist []error
    59  	errh := func(err error) { errlist = append(errlist, err) }
    60  	for i, filename := range filenames {
    61  		base := syntax.NewFileBase(filename)
    62  		r := bytes.NewReader(srcs[i])
    63  		file, err := syntax.Parse(base, r, errh, nil, mode)
    64  		if file == nil {
    65  			t.Fatalf("%s: %s", filename, err)
    66  		}
    67  		files = append(files, file)
    68  	}
    69  	return files, errlist
    70  }
    71  
    72  func unpackError(err error) (syntax.Pos, string) {
    73  	switch err := err.(type) {
    74  	case syntax.Error:
    75  		return err.Pos, err.Msg
    76  	case Error:
    77  		return err.Pos, err.Msg
    78  	default:
    79  		return nopos, err.Error()
    80  	}
    81  }
    82  
    83  // absDiff returns the absolute difference between x and y.
    84  func absDiff(x, y uint) uint {
    85  	if x < y {
    86  		return y - x
    87  	}
    88  	return x - y
    89  }
    90  
    91  // parseFlags parses flags from the first line of the given source if the line
    92  // starts with "//" (line comment) followed by "-" (possibly with spaces
    93  // between). Otherwise the line is ignored.
    94  func parseFlags(src []byte, flags *flag.FlagSet) error {
    95  	// we must have a line comment that starts with a "-"
    96  	const prefix = "//"
    97  	if !bytes.HasPrefix(src, []byte(prefix)) {
    98  		return nil // first line is not a line comment
    99  	}
   100  	src = src[len(prefix):]
   101  	if i := bytes.Index(src, []byte("-")); i < 0 || len(bytes.TrimSpace(src[:i])) != 0 {
   102  		return nil // comment doesn't start with a "-"
   103  	}
   104  	end := bytes.Index(src, []byte("\n"))
   105  	const maxLen = 256
   106  	if end < 0 || end > maxLen {
   107  		return fmt.Errorf("flags comment line too long")
   108  	}
   109  
   110  	return flags.Parse(strings.Fields(string(src[:end])))
   111  }
   112  
   113  // testFiles type-checks the package consisting of the given files, and
   114  // compares the resulting errors with the ERROR annotations in the source.
   115  // Except for manual tests, each package is type-checked twice, once without
   116  // use of Alias types, and once with Alias types.
   117  //
   118  // The srcs slice contains the file content for the files named in the
   119  // filenames slice. The colDelta parameter specifies the tolerance for position
   120  // mismatch when comparing errors. The manual parameter specifies whether this
   121  // is a 'manual' test.
   122  //
   123  // If provided, opts may be used to mutate the Config before type-checking.
   124  func testFiles(t *testing.T, filenames []string, srcs [][]byte, colDelta uint, manual bool, opts ...func(*Config)) {
   125  	enableAlias := true
   126  	opts = append(opts, func(conf *Config) { conf.EnableAlias = enableAlias })
   127  	testFilesImpl(t, filenames, srcs, colDelta, manual, opts...)
   128  	if !manual {
   129  		enableAlias = false
   130  		testFilesImpl(t, filenames, srcs, colDelta, manual, opts...)
   131  	}
   132  }
   133  
   134  func testFilesImpl(t *testing.T, filenames []string, srcs [][]byte, colDelta uint, manual bool, opts ...func(*Config)) {
   135  	if len(filenames) == 0 {
   136  		t.Fatal("no source files")
   137  	}
   138  
   139  	// parse files
   140  	files, errlist := parseFiles(t, filenames, srcs, 0)
   141  	pkgName := "<no package>"
   142  	if len(files) > 0 {
   143  		pkgName = files[0].PkgName.Value
   144  	}
   145  	listErrors := manual && !*verifyErrors
   146  	if listErrors && len(errlist) > 0 {
   147  		t.Errorf("--- %s:", pkgName)
   148  		for _, err := range errlist {
   149  			t.Error(err)
   150  		}
   151  	}
   152  
   153  	// set up typechecker
   154  	var conf Config
   155  	conf.Trace = manual && testing.Verbose()
   156  	conf.Importer = defaultImporter()
   157  	conf.Error = func(err error) {
   158  		if *haltOnError {
   159  			defer panic(err)
   160  		}
   161  		if listErrors {
   162  			t.Error(err)
   163  			return
   164  		}
   165  		errlist = append(errlist, err)
   166  	}
   167  
   168  	// apply custom configuration
   169  	for _, opt := range opts {
   170  		opt(&conf)
   171  	}
   172  
   173  	// apply flag setting (overrides custom configuration)
   174  	var goexperiment, gotypesalias string
   175  	flags := flag.NewFlagSet("", flag.PanicOnError)
   176  	flags.StringVar(&conf.GoVersion, "lang", "", "")
   177  	flags.StringVar(&goexperiment, "goexperiment", "", "")
   178  	flags.BoolVar(&conf.FakeImportC, "fakeImportC", false, "")
   179  	flags.StringVar(&gotypesalias, "gotypesalias", "", "")
   180  	if err := parseFlags(srcs[0], flags); err != nil {
   181  		t.Fatal(err)
   182  	}
   183  
   184  	exp, err := buildcfg.ParseGOEXPERIMENT(runtime.GOOS, runtime.GOARCH, goexperiment)
   185  	if err != nil {
   186  		t.Fatal(err)
   187  	}
   188  	old := buildcfg.Experiment
   189  	defer func() {
   190  		buildcfg.Experiment = old
   191  	}()
   192  	buildcfg.Experiment = *exp
   193  
   194  	// By default, gotypesalias is not set.
   195  	if gotypesalias != "" {
   196  		conf.EnableAlias = gotypesalias != "0"
   197  	}
   198  
   199  	// Provide Config.Info with all maps so that info recording is tested.
   200  	info := Info{
   201  		Types:        make(map[syntax.Expr]TypeAndValue),
   202  		Instances:    make(map[*syntax.Name]Instance),
   203  		Defs:         make(map[*syntax.Name]Object),
   204  		Uses:         make(map[*syntax.Name]Object),
   205  		Implicits:    make(map[syntax.Node]Object),
   206  		Selections:   make(map[*syntax.SelectorExpr]*Selection),
   207  		Scopes:       make(map[syntax.Node]*Scope),
   208  		FileVersions: make(map[*syntax.PosBase]string),
   209  	}
   210  
   211  	// typecheck
   212  	conf.Check(pkgName, files, &info)
   213  	if listErrors {
   214  		return
   215  	}
   216  
   217  	// collect expected errors
   218  	errmap := make(map[string]map[uint][]syntax.Error)
   219  	for i, filename := range filenames {
   220  		if m := syntax.CommentMap(bytes.NewReader(srcs[i]), regexp.MustCompile("^ ERRORx? ")); len(m) > 0 {
   221  			errmap[filename] = m
   222  		}
   223  	}
   224  
   225  	// match against found errors
   226  	var indices []int // list indices of matching errors, reused for each error
   227  	for _, err := range errlist {
   228  		gotPos, gotMsg := unpackError(err)
   229  
   230  		// find list of errors for the respective error line
   231  		filename := gotPos.Base().Filename()
   232  		filemap := errmap[filename]
   233  		line := gotPos.Line()
   234  		var errList []syntax.Error
   235  		if filemap != nil {
   236  			errList = filemap[line]
   237  		}
   238  
   239  		// At least one of the errors in errList should match the current error.
   240  		indices = indices[:0]
   241  		for i, want := range errList {
   242  			pattern, substr := strings.CutPrefix(want.Msg, " ERROR ")
   243  			if !substr {
   244  				var found bool
   245  				pattern, found = strings.CutPrefix(want.Msg, " ERRORx ")
   246  				if !found {
   247  					panic("unreachable")
   248  				}
   249  			}
   250  			pattern, err := strconv.Unquote(strings.TrimSpace(pattern))
   251  			if err != nil {
   252  				t.Errorf("%s:%d:%d: %v", filename, line, want.Pos.Col(), err)
   253  				continue
   254  			}
   255  			if substr {
   256  				if !strings.Contains(gotMsg, pattern) {
   257  					continue
   258  				}
   259  			} else {
   260  				rx, err := regexp.Compile(pattern)
   261  				if err != nil {
   262  					t.Errorf("%s:%d:%d: %v", filename, line, want.Pos.Col(), err)
   263  					continue
   264  				}
   265  				if !rx.MatchString(gotMsg) {
   266  					continue
   267  				}
   268  			}
   269  			indices = append(indices, i)
   270  		}
   271  		if len(indices) == 0 {
   272  			t.Errorf("%s: no error expected: %q", gotPos, gotMsg)
   273  			continue
   274  		}
   275  		// len(indices) > 0
   276  
   277  		// If there are multiple matching errors, select the one with the closest column position.
   278  		index := -1 // index of matching error
   279  		var delta uint
   280  		for _, i := range indices {
   281  			if d := absDiff(gotPos.Col(), errList[i].Pos.Col()); index < 0 || d < delta {
   282  				index, delta = i, d
   283  			}
   284  		}
   285  
   286  		// The closest column position must be within expected colDelta.
   287  		if delta > colDelta {
   288  			t.Errorf("%s: got col = %d; want %d", gotPos, gotPos.Col(), errList[index].Pos.Col())
   289  		}
   290  
   291  		// eliminate from errList
   292  		if n := len(errList) - 1; n > 0 {
   293  			// not the last entry - slide entries down (don't reorder)
   294  			copy(errList[index:], errList[index+1:])
   295  			filemap[line] = errList[:n]
   296  		} else {
   297  			// last entry - remove errList from filemap
   298  			delete(filemap, line)
   299  		}
   300  
   301  		// if filemap is empty, eliminate from errmap
   302  		if len(filemap) == 0 {
   303  			delete(errmap, filename)
   304  		}
   305  	}
   306  
   307  	// there should be no expected errors left
   308  	if len(errmap) > 0 {
   309  		t.Errorf("--- %s: unreported errors:", pkgName)
   310  		for filename, filemap := range errmap {
   311  			for line, errList := range filemap {
   312  				for _, err := range errList {
   313  					t.Errorf("%s:%d:%d: %s", filename, line, err.Pos.Col(), err.Msg)
   314  				}
   315  			}
   316  		}
   317  	}
   318  }
   319  
   320  // boolFieldAddr(conf, name) returns the address of the boolean field conf.<name>.
   321  // For accessing unexported fields.
   322  func boolFieldAddr(conf *Config, name string) *bool {
   323  	v := reflect.Indirect(reflect.ValueOf(conf))
   324  	return (*bool)(v.FieldByName(name).Addr().UnsafePointer())
   325  }
   326  
   327  // TestManual is for manual testing of a package - either provided
   328  // as a list of filenames belonging to the package, or a directory
   329  // name containing the package files - after the test arguments
   330  // (and a separating "--"). For instance, to test the package made
   331  // of the files foo.go and bar.go, use:
   332  //
   333  //	go test -run Manual -- foo.go bar.go
   334  //
   335  // If no source arguments are provided, the file testdata/manual.go
   336  // is used instead.
   337  // Provide the -verify flag to verify errors against ERROR comments
   338  // in the input files rather than having a list of errors reported.
   339  // The accepted Go language version can be controlled with the -lang
   340  // flag.
   341  func TestManual(t *testing.T) {
   342  	testenv.MustHaveGoBuild(t)
   343  
   344  	filenames := flag.Args()
   345  	if len(filenames) == 0 {
   346  		filenames = []string{filepath.FromSlash("testdata/manual.go")}
   347  	}
   348  
   349  	info, err := os.Stat(filenames[0])
   350  	if err != nil {
   351  		t.Fatalf("TestManual: %v", err)
   352  	}
   353  
   354  	DefPredeclaredTestFuncs()
   355  	if info.IsDir() {
   356  		if len(filenames) > 1 {
   357  			t.Fatal("TestManual: must have only one directory argument")
   358  		}
   359  		testDir(t, filenames[0], 0, true)
   360  	} else {
   361  		testPkg(t, filenames, 0, true)
   362  	}
   363  }
   364  
   365  func TestLongConstants(t *testing.T) {
   366  	format := `package longconst; const _ = %s /* ERROR "constant overflow" */; const _ = %s // ERROR "excessively long constant"`
   367  	src := fmt.Sprintf(format, strings.Repeat("1", 9999), strings.Repeat("1", 10001))
   368  	testFiles(t, []string{"longconst.go"}, [][]byte{[]byte(src)}, 0, false)
   369  }
   370  
   371  func withSizes(sizes Sizes) func(*Config) {
   372  	return func(cfg *Config) {
   373  		cfg.Sizes = sizes
   374  	}
   375  }
   376  
   377  // TestIndexRepresentability tests that constant index operands must
   378  // be representable as int even if they already have a type that can
   379  // represent larger values.
   380  func TestIndexRepresentability(t *testing.T) {
   381  	const src = `package index; var s []byte; var _ = s[int64 /* ERRORx "int64\\(1\\) << 40 \\(.*\\) overflows int" */ (1) << 40]`
   382  	testFiles(t, []string{"index.go"}, [][]byte{[]byte(src)}, 0, false, withSizes(&StdSizes{4, 4}))
   383  }
   384  
   385  func TestIssue47243_TypedRHS(t *testing.T) {
   386  	// The RHS of the shift expression below overflows uint on 32bit platforms,
   387  	// but this is OK as it is explicitly typed.
   388  	const src = `package issue47243; var a uint64; var _ = a << uint64(4294967296)` // uint64(1<<32)
   389  	testFiles(t, []string{"p.go"}, [][]byte{[]byte(src)}, 0, false, withSizes(&StdSizes{4, 4}))
   390  }
   391  
   392  func TestCheck(t *testing.T) {
   393  	old := buildcfg.Experiment.RangeFunc
   394  	defer func() {
   395  		buildcfg.Experiment.RangeFunc = old
   396  	}()
   397  	buildcfg.Experiment.RangeFunc = true
   398  
   399  	DefPredeclaredTestFuncs()
   400  	testDirFiles(t, "../../../../internal/types/testdata/check", 50, false) // TODO(gri) narrow column tolerance
   401  }
   402  func TestSpec(t *testing.T) { testDirFiles(t, "../../../../internal/types/testdata/spec", 20, false) } // TODO(gri) narrow column tolerance
   403  func TestExamples(t *testing.T) {
   404  	testDirFiles(t, "../../../../internal/types/testdata/examples", 125, false)
   405  } // TODO(gri) narrow column tolerance
   406  func TestFixedbugs(t *testing.T) {
   407  	testDirFiles(t, "../../../../internal/types/testdata/fixedbugs", 100, false)
   408  }                            // TODO(gri) narrow column tolerance
   409  func TestLocal(t *testing.T) { testDirFiles(t, "testdata/local", 0, false) }
   410  
   411  func testDirFiles(t *testing.T, dir string, colDelta uint, manual bool) {
   412  	testenv.MustHaveGoBuild(t)
   413  	dir = filepath.FromSlash(dir)
   414  
   415  	fis, err := os.ReadDir(dir)
   416  	if err != nil {
   417  		t.Error(err)
   418  		return
   419  	}
   420  
   421  	for _, fi := range fis {
   422  		path := filepath.Join(dir, fi.Name())
   423  
   424  		// If fi is a directory, its files make up a single package.
   425  		if fi.IsDir() {
   426  			testDir(t, path, colDelta, manual)
   427  		} else {
   428  			t.Run(filepath.Base(path), func(t *testing.T) {
   429  				testPkg(t, []string{path}, colDelta, manual)
   430  			})
   431  		}
   432  	}
   433  }
   434  
   435  func testDir(t *testing.T, dir string, colDelta uint, manual bool) {
   436  	fis, err := os.ReadDir(dir)
   437  	if err != nil {
   438  		t.Error(err)
   439  		return
   440  	}
   441  
   442  	var filenames []string
   443  	for _, fi := range fis {
   444  		filenames = append(filenames, filepath.Join(dir, fi.Name()))
   445  	}
   446  
   447  	t.Run(filepath.Base(dir), func(t *testing.T) {
   448  		testPkg(t, filenames, colDelta, manual)
   449  	})
   450  }
   451  
   452  func testPkg(t *testing.T, filenames []string, colDelta uint, manual bool) {
   453  	srcs := make([][]byte, len(filenames))
   454  	for i, filename := range filenames {
   455  		src, err := os.ReadFile(filename)
   456  		if err != nil {
   457  			t.Fatalf("could not read %s: %v", filename, err)
   458  		}
   459  		srcs[i] = src
   460  	}
   461  	testFiles(t, filenames, srcs, colDelta, manual)
   462  }
   463
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