vet_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  package main
     6  
     7  import (
     8  	"bytes"
     9  	"errors"
    10  	"fmt"
    11  	"internal/testenv"
    12  	"log"
    13  	"os"
    14  	"os/exec"
    15  	"path"
    16  	"path/filepath"
    17  	"regexp"
    18  	"strconv"
    19  	"strings"
    20  	"testing"
    21  )
    22  
    23  // TestMain executes the test binary as the vet command if
    24  // GO_VETTEST_IS_VET is set, and runs the tests otherwise.
    25  func TestMain(m *testing.M) {
    26  	if os.Getenv("GO_VETTEST_IS_VET") != "" {
    27  		main()
    28  		os.Exit(0)
    29  	}
    30  
    31  	os.Setenv("GO_VETTEST_IS_VET", "1") // Set for subprocesses to inherit.
    32  	os.Exit(m.Run())
    33  }
    34  
    35  // vetPath returns the path to the "vet" binary to run.
    36  func vetPath(t testing.TB) string {
    37  	return testenv.Executable(t)
    38  }
    39  
    40  func vetCmd(t *testing.T, arg, pkg string) *exec.Cmd {
    41  	cmd := testenv.Command(t, testenv.GoToolPath(t), "vet", "-vettool="+vetPath(t), arg, path.Join("cmd/vet/testdata", pkg))
    42  	cmd.Env = os.Environ()
    43  	return cmd
    44  }
    45  
    46  func TestVet(t *testing.T) {
    47  	t.Parallel()
    48  	for _, pkg := range []string{
    49  		"appends",
    50  		"asm",
    51  		"assign",
    52  		"atomic",
    53  		"bool",
    54  		"buildtag",
    55  		"cgo",
    56  		"composite",
    57  		"copylock",
    58  		"deadcode",
    59  		"directive",
    60  		"httpresponse",
    61  		"lostcancel",
    62  		"method",
    63  		"nilfunc",
    64  		"print",
    65  		"shift",
    66  		"slog",
    67  		"structtag",
    68  		"testingpkg",
    69  		// "testtag" has its own test
    70  		"unmarshal",
    71  		"unsafeptr",
    72  		"unused",
    73  	} {
    74  		pkg := pkg
    75  		t.Run(pkg, func(t *testing.T) {
    76  			t.Parallel()
    77  
    78  			// Skip cgo test on platforms without cgo.
    79  			if pkg == "cgo" && !cgoEnabled(t) {
    80  				return
    81  			}
    82  
    83  			cmd := vetCmd(t, "-printfuncs=Warn,Warnf", pkg)
    84  
    85  			// The asm test assumes amd64.
    86  			if pkg == "asm" {
    87  				cmd.Env = append(cmd.Env, "GOOS=linux", "GOARCH=amd64")
    88  			}
    89  
    90  			dir := filepath.Join("testdata", pkg)
    91  			gos, err := filepath.Glob(filepath.Join(dir, "*.go"))
    92  			if err != nil {
    93  				t.Fatal(err)
    94  			}
    95  			asms, err := filepath.Glob(filepath.Join(dir, "*.s"))
    96  			if err != nil {
    97  				t.Fatal(err)
    98  			}
    99  			var files []string
   100  			files = append(files, gos...)
   101  			files = append(files, asms...)
   102  
   103  			errchk(cmd, files, t)
   104  		})
   105  	}
   106  
   107  	// The loopclosure analyzer (aka "rangeloop" before CL 140578)
   108  	// is a no-op for files whose version >= go1.22, so we use a
   109  	// go.mod file in the rangeloop directory to "downgrade".
   110  	//
   111  	// TOOD(adonovan): delete when go1.21 goes away.
   112  	t.Run("loopclosure", func(t *testing.T) {
   113  		cmd := testenv.Command(t, testenv.GoToolPath(t), "vet", "-vettool="+vetPath(t), ".")
   114  		cmd.Env = append(os.Environ(), "GOWORK=off")
   115  		cmd.Dir = "testdata/rangeloop"
   116  		cmd.Stderr = new(strings.Builder) // all vet output goes to stderr
   117  		cmd.Run()
   118  		stderr := cmd.Stderr.(fmt.Stringer).String()
   119  
   120  		filename := filepath.FromSlash("testdata/rangeloop/rangeloop.go")
   121  
   122  		// Unlike the tests above, which runs vet in cmd/vet/, this one
   123  		// runs it in subdirectory, so the "full names" in the output
   124  		// are in fact short "./rangeloop.go".
   125  		// But we can't just pass "./rangeloop.go" as the "full name"
   126  		// argument to errorCheck as it does double duty as both a
   127  		// string that appears in the output, and as file name
   128  		// openable relative to the test directory, containing text
   129  		// expectations.
   130  		//
   131  		// So, we munge the file.
   132  		stderr = strings.ReplaceAll(stderr, filepath.FromSlash("./rangeloop.go"), filename)
   133  
   134  		if err := errorCheck(stderr, false, filename, filepath.Base(filename)); err != nil {
   135  			t.Errorf("error check failed: %s", err)
   136  			t.Log("vet stderr:\n", cmd.Stderr)
   137  		}
   138  	})
   139  
   140  	// The stdversion analyzer requires a lower-than-tip go
   141  	// version in its go.mod file for it to report anything.
   142  	// So again we use a testdata go.mod file to "downgrade".
   143  	t.Run("stdversion", func(t *testing.T) {
   144  		cmd := testenv.Command(t, testenv.GoToolPath(t), "vet", "-vettool="+vetPath(t), ".")
   145  		cmd.Env = append(os.Environ(), "GOWORK=off")
   146  		cmd.Dir = "testdata/stdversion"
   147  		cmd.Stderr = new(strings.Builder) // all vet output goes to stderr
   148  		cmd.Run()
   149  		stderr := cmd.Stderr.(fmt.Stringer).String()
   150  
   151  		filename := filepath.FromSlash("testdata/stdversion/stdversion.go")
   152  
   153  		// Unlike the tests above, which runs vet in cmd/vet/, this one
   154  		// runs it in subdirectory, so the "full names" in the output
   155  		// are in fact short "./rangeloop.go".
   156  		// But we can't just pass "./rangeloop.go" as the "full name"
   157  		// argument to errorCheck as it does double duty as both a
   158  		// string that appears in the output, and as file name
   159  		// openable relative to the test directory, containing text
   160  		// expectations.
   161  		//
   162  		// So, we munge the file.
   163  		stderr = strings.ReplaceAll(stderr, filepath.FromSlash("./stdversion.go"), filename)
   164  
   165  		if err := errorCheck(stderr, false, filename, filepath.Base(filename)); err != nil {
   166  			t.Errorf("error check failed: %s", err)
   167  			t.Log("vet stderr:\n", cmd.Stderr)
   168  		}
   169  	})
   170  }
   171  
   172  func cgoEnabled(t *testing.T) bool {
   173  	// Don't trust build.Default.CgoEnabled as it is false for
   174  	// cross-builds unless CGO_ENABLED is explicitly specified.
   175  	// That's fine for the builders, but causes commands like
   176  	// 'GOARCH=386 go test .' to fail.
   177  	// Instead, we ask the go command.
   178  	cmd := testenv.Command(t, testenv.GoToolPath(t), "list", "-f", "{{context.CgoEnabled}}")
   179  	out, _ := cmd.CombinedOutput()
   180  	return string(out) == "true\n"
   181  }
   182  
   183  func errchk(c *exec.Cmd, files []string, t *testing.T) {
   184  	output, err := c.CombinedOutput()
   185  	if _, ok := err.(*exec.ExitError); !ok {
   186  		t.Logf("vet output:\n%s", output)
   187  		t.Fatal(err)
   188  	}
   189  	fullshort := make([]string, 0, len(files)*2)
   190  	for _, f := range files {
   191  		fullshort = append(fullshort, f, filepath.Base(f))
   192  	}
   193  	err = errorCheck(string(output), false, fullshort...)
   194  	if err != nil {
   195  		t.Errorf("error check failed: %s", err)
   196  	}
   197  }
   198  
   199  // TestTags verifies that the -tags argument controls which files to check.
   200  func TestTags(t *testing.T) {
   201  	t.Parallel()
   202  	for tag, wantFile := range map[string]int{
   203  		"testtag":     1, // file1
   204  		"x testtag y": 1,
   205  		"othertag":    2,
   206  	} {
   207  		tag, wantFile := tag, wantFile
   208  		t.Run(tag, func(t *testing.T) {
   209  			t.Parallel()
   210  			t.Logf("-tags=%s", tag)
   211  			cmd := vetCmd(t, "-tags="+tag, "tagtest")
   212  			output, err := cmd.CombinedOutput()
   213  
   214  			want := fmt.Sprintf("file%d.go", wantFile)
   215  			dontwant := fmt.Sprintf("file%d.go", 3-wantFile)
   216  
   217  			// file1 has testtag and file2 has !testtag.
   218  			if !bytes.Contains(output, []byte(filepath.Join("tagtest", want))) {
   219  				t.Errorf("%s: %s was excluded, should be included", tag, want)
   220  			}
   221  			if bytes.Contains(output, []byte(filepath.Join("tagtest", dontwant))) {
   222  				t.Errorf("%s: %s was included, should be excluded", tag, dontwant)
   223  			}
   224  			if t.Failed() {
   225  				t.Logf("err=%s, output=<<%s>>", err, output)
   226  			}
   227  		})
   228  	}
   229  }
   230  
   231  // All declarations below were adapted from test/run.go.
   232  
   233  // errorCheck matches errors in outStr against comments in source files.
   234  // For each line of the source files which should generate an error,
   235  // there should be a comment of the form // ERROR "regexp".
   236  // If outStr has an error for a line which has no such comment,
   237  // this function will report an error.
   238  // Likewise if outStr does not have an error for a line which has a comment,
   239  // or if the error message does not match the <regexp>.
   240  // The <regexp> syntax is Perl but it's best to stick to egrep.
   241  //
   242  // Sources files are supplied as fullshort slice.
   243  // It consists of pairs: full path to source file and its base name.
   244  func errorCheck(outStr string, wantAuto bool, fullshort ...string) (err error) {
   245  	var errs []error
   246  	out := splitOutput(outStr, wantAuto)
   247  	// Cut directory name.
   248  	for i := range out {
   249  		for j := 0; j < len(fullshort); j += 2 {
   250  			full, short := fullshort[j], fullshort[j+1]
   251  			out[i] = strings.ReplaceAll(out[i], full, short)
   252  		}
   253  	}
   254  
   255  	var want []wantedError
   256  	for j := 0; j < len(fullshort); j += 2 {
   257  		full, short := fullshort[j], fullshort[j+1]
   258  		want = append(want, wantedErrors(full, short)...)
   259  	}
   260  	for _, we := range want {
   261  		var errmsgs []string
   262  		if we.auto {
   263  			errmsgs, out = partitionStrings("<autogenerated>", out)
   264  		} else {
   265  			errmsgs, out = partitionStrings(we.prefix, out)
   266  		}
   267  		if len(errmsgs) == 0 {
   268  			errs = append(errs, fmt.Errorf("%s:%d: missing error %q", we.file, we.lineNum, we.reStr))
   269  			continue
   270  		}
   271  		matched := false
   272  		n := len(out)
   273  		for _, errmsg := range errmsgs {
   274  			// Assume errmsg says "file:line: foo".
   275  			// Cut leading "file:line: " to avoid accidental matching of file name instead of message.
   276  			text := errmsg
   277  			if _, suffix, ok := strings.Cut(text, " "); ok {
   278  				text = suffix
   279  			}
   280  			if we.re.MatchString(text) {
   281  				matched = true
   282  			} else {
   283  				out = append(out, errmsg)
   284  			}
   285  		}
   286  		if !matched {
   287  			errs = append(errs, fmt.Errorf("%s:%d: no match for %#q in:\n\t%s", we.file, we.lineNum, we.reStr, strings.Join(out[n:], "\n\t")))
   288  			continue
   289  		}
   290  	}
   291  
   292  	if len(out) > 0 {
   293  		errs = append(errs, fmt.Errorf("Unmatched Errors:"))
   294  		for _, errLine := range out {
   295  			errs = append(errs, fmt.Errorf("%s", errLine))
   296  		}
   297  	}
   298  
   299  	if len(errs) == 0 {
   300  		return nil
   301  	}
   302  	if len(errs) == 1 {
   303  		return errs[0]
   304  	}
   305  	var buf strings.Builder
   306  	fmt.Fprintf(&buf, "\n")
   307  	for _, err := range errs {
   308  		fmt.Fprintf(&buf, "%s\n", err.Error())
   309  	}
   310  	return errors.New(buf.String())
   311  }
   312  
   313  func splitOutput(out string, wantAuto bool) []string {
   314  	// gc error messages continue onto additional lines with leading tabs.
   315  	// Split the output at the beginning of each line that doesn't begin with a tab.
   316  	// <autogenerated> lines are impossible to match so those are filtered out.
   317  	var res []string
   318  	for _, line := range strings.Split(out, "\n") {
   319  		line = strings.TrimSuffix(line, "\r") // normalize Windows output
   320  		if strings.HasPrefix(line, "\t") {
   321  			res[len(res)-1] += "\n" + line
   322  		} else if strings.HasPrefix(line, "go tool") || strings.HasPrefix(line, "#") || !wantAuto && strings.HasPrefix(line, "<autogenerated>") {
   323  			continue
   324  		} else if strings.TrimSpace(line) != "" {
   325  			res = append(res, line)
   326  		}
   327  	}
   328  	return res
   329  }
   330  
   331  // matchPrefix reports whether s starts with file name prefix followed by a :,
   332  // and possibly preceded by a directory name.
   333  func matchPrefix(s, prefix string) bool {
   334  	i := strings.Index(s, ":")
   335  	if i < 0 {
   336  		return false
   337  	}
   338  	j := strings.LastIndex(s[:i], "/")
   339  	s = s[j+1:]
   340  	if len(s) <= len(prefix) || s[:len(prefix)] != prefix {
   341  		return false
   342  	}
   343  	if s[len(prefix)] == ':' {
   344  		return true
   345  	}
   346  	return false
   347  }
   348  
   349  func partitionStrings(prefix string, strs []string) (matched, unmatched []string) {
   350  	for _, s := range strs {
   351  		if matchPrefix(s, prefix) {
   352  			matched = append(matched, s)
   353  		} else {
   354  			unmatched = append(unmatched, s)
   355  		}
   356  	}
   357  	return
   358  }
   359  
   360  type wantedError struct {
   361  	reStr   string
   362  	re      *regexp.Regexp
   363  	lineNum int
   364  	auto    bool // match <autogenerated> line
   365  	file    string
   366  	prefix  string
   367  }
   368  
   369  var (
   370  	errRx       = regexp.MustCompile(`// (?:GC_)?ERROR(NEXT)? (.*)`)
   371  	errAutoRx   = regexp.MustCompile(`// (?:GC_)?ERRORAUTO(NEXT)? (.*)`)
   372  	errQuotesRx = regexp.MustCompile(`"([^"]*)"`)
   373  	lineRx      = regexp.MustCompile(`LINE(([+-])(\d+))?`)
   374  )
   375  
   376  // wantedErrors parses expected errors from comments in a file.
   377  func wantedErrors(file, short string) (errs []wantedError) {
   378  	cache := make(map[string]*regexp.Regexp)
   379  
   380  	src, err := os.ReadFile(file)
   381  	if err != nil {
   382  		log.Fatal(err)
   383  	}
   384  	for i, line := range strings.Split(string(src), "\n") {
   385  		lineNum := i + 1
   386  		if strings.Contains(line, "////") {
   387  			// double comment disables ERROR
   388  			continue
   389  		}
   390  		var auto bool
   391  		m := errAutoRx.FindStringSubmatch(line)
   392  		if m != nil {
   393  			auto = true
   394  		} else {
   395  			m = errRx.FindStringSubmatch(line)
   396  		}
   397  		if m == nil {
   398  			continue
   399  		}
   400  		if m[1] == "NEXT" {
   401  			lineNum++
   402  		}
   403  		all := m[2]
   404  		mm := errQuotesRx.FindAllStringSubmatch(all, -1)
   405  		if mm == nil {
   406  			log.Fatalf("%s:%d: invalid errchk line: %s", file, lineNum, line)
   407  		}
   408  		for _, m := range mm {
   409  			replacedOnce := false
   410  			rx := lineRx.ReplaceAllStringFunc(m[1], func(m string) string {
   411  				if replacedOnce {
   412  					return m
   413  				}
   414  				replacedOnce = true
   415  				n := lineNum
   416  				if strings.HasPrefix(m, "LINE+") {
   417  					delta, _ := strconv.Atoi(m[5:])
   418  					n += delta
   419  				} else if strings.HasPrefix(m, "LINE-") {
   420  					delta, _ := strconv.Atoi(m[5:])
   421  					n -= delta
   422  				}
   423  				return fmt.Sprintf("%s:%d", short, n)
   424  			})
   425  			re := cache[rx]
   426  			if re == nil {
   427  				var err error
   428  				re, err = regexp.Compile(rx)
   429  				if err != nil {
   430  					log.Fatalf("%s:%d: invalid regexp \"%#q\" in ERROR line: %v", file, lineNum, rx, err)
   431  				}
   432  				cache[rx] = re
   433  			}
   434  			prefix := fmt.Sprintf("%s:%d", short, lineNum)
   435  			errs = append(errs, wantedError{
   436  				reStr:   rx,
   437  				re:      re,
   438  				prefix:  prefix,
   439  				auto:    auto,
   440  				lineNum: lineNum,
   441  				file:    short,
   442  			})
   443  		}
   444  	}
   445  
   446  	return
   447  }
   448
View as plain text