parser_test.go

     1  // Copyright 2016 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 syntax
     6  
     7  import (
     8  	"bytes"
     9  	"flag"
    10  	"fmt"
    11  	"io/ioutil"
    12  	"path/filepath"
    13  	"regexp"
    14  	"runtime"
    15  	"strings"
    16  	"sync"
    17  	"testing"
    18  	"time"
    19  )
    20  
    21  var (
    22  	fast   = flag.Bool("fast", false, "parse package files in parallel")
    23  	verify = flag.Bool("verify", false, "verify idempotent printing")
    24  	src_   = flag.String("src", "parser.go", "source file to parse")
    25  	skip   = flag.String("skip", "", "files matching this regular expression are skipped by TestStdLib")
    26  )
    27  
    28  func TestParse(t *testing.T) {
    29  	ParseFile(*src_, func(err error) { t.Error(err) }, nil, AllowGenerics)
    30  }
    31  
    32  func TestVerify(t *testing.T) {
    33  	ast, err := ParseFile(*src_, func(err error) { t.Error(err) }, nil, AllowGenerics)
    34  	if err != nil {
    35  		return // error already reported
    36  	}
    37  	verifyPrint(t, *src_, ast)
    38  }
    39  
    40  func TestParseGo2(t *testing.T) {
    41  	dir := filepath.Join(testdata, "go2")
    42  	list, err := ioutil.ReadDir(dir)
    43  	if err != nil {
    44  		t.Fatal(err)
    45  	}
    46  	for _, fi := range list {
    47  		name := fi.Name()
    48  		if !fi.IsDir() && !strings.HasPrefix(name, ".") {
    49  			ParseFile(filepath.Join(dir, name), func(err error) { t.Error(err) }, nil, AllowGenerics|AllowMethodTypeParams)
    50  		}
    51  	}
    52  }
    53  
    54  func TestStdLib(t *testing.T) {
    55  	if testing.Short() {
    56  		t.Skip("skipping test in short mode")
    57  	}
    58  
    59  	var skipRx *regexp.Regexp
    60  	if *skip != "" {
    61  		var err error
    62  		skipRx, err = regexp.Compile(*skip)
    63  		if err != nil {
    64  			t.Fatalf("invalid argument for -skip (%v)", err)
    65  		}
    66  	}
    67  
    68  	var m1 runtime.MemStats
    69  	runtime.ReadMemStats(&m1)
    70  	start := time.Now()
    71  
    72  	type parseResult struct {
    73  		filename string
    74  		lines    uint
    75  	}
    76  
    77  	results := make(chan parseResult)
    78  	go func() {
    79  		defer close(results)
    80  		for _, dir := range []string{
    81  			runtime.GOROOT(),
    82  		} {
    83  			walkDirs(t, dir, func(filename string) {
    84  				if skipRx != nil && skipRx.MatchString(filename) {
    85  					// Always report skipped files since regexp
    86  					// typos can lead to surprising results.
    87  					fmt.Printf("skipping %s\n", filename)
    88  					return
    89  				}
    90  				if debug {
    91  					fmt.Printf("parsing %s\n", filename)
    92  				}
    93  				ast, err := ParseFile(filename, nil, nil, AllowGenerics)
    94  				if err != nil {
    95  					t.Error(err)
    96  					return
    97  				}
    98  				if *verify {
    99  					verifyPrint(t, filename, ast)
   100  				}
   101  				results <- parseResult{filename, ast.EOF.Line()}
   102  			})
   103  		}
   104  	}()
   105  
   106  	var count, lines uint
   107  	for res := range results {
   108  		count++
   109  		lines += res.lines
   110  		if testing.Verbose() {
   111  			fmt.Printf("%5d  %s (%d lines)\n", count, res.filename, res.lines)
   112  		}
   113  	}
   114  
   115  	dt := time.Since(start)
   116  	var m2 runtime.MemStats
   117  	runtime.ReadMemStats(&m2)
   118  	dm := float64(m2.TotalAlloc-m1.TotalAlloc) / 1e6
   119  
   120  	fmt.Printf("parsed %d lines (%d files) in %v (%d lines/s)\n", lines, count, dt, int64(float64(lines)/dt.Seconds()))
   121  	fmt.Printf("allocated %.3fMb (%.3fMb/s)\n", dm, dm/dt.Seconds())
   122  }
   123  
   124  func walkDirs(t *testing.T, dir string, action func(string)) {
   125  	fis, err := ioutil.ReadDir(dir)
   126  	if err != nil {
   127  		t.Error(err)
   128  		return
   129  	}
   130  
   131  	var files, dirs []string
   132  	for _, fi := range fis {
   133  		if fi.Mode().IsRegular() {
   134  			if strings.HasSuffix(fi.Name(), ".go") {
   135  				path := filepath.Join(dir, fi.Name())
   136  				files = append(files, path)
   137  			}
   138  		} else if fi.IsDir() && fi.Name() != "testdata" {
   139  			path := filepath.Join(dir, fi.Name())
   140  			if !strings.HasSuffix(path, string(filepath.Separator)+"test") {
   141  				dirs = append(dirs, path)
   142  			}
   143  		}
   144  	}
   145  
   146  	if *fast {
   147  		var wg sync.WaitGroup
   148  		wg.Add(len(files))
   149  		for _, filename := range files {
   150  			go func(filename string) {
   151  				defer wg.Done()
   152  				action(filename)
   153  			}(filename)
   154  		}
   155  		wg.Wait()
   156  	} else {
   157  		for _, filename := range files {
   158  			action(filename)
   159  		}
   160  	}
   161  
   162  	for _, dir := range dirs {
   163  		walkDirs(t, dir, action)
   164  	}
   165  }
   166  
   167  func verifyPrint(t *testing.T, filename string, ast1 *File) {
   168  	var buf1 bytes.Buffer
   169  	_, err := Fprint(&buf1, ast1, LineForm)
   170  	if err != nil {
   171  		panic(err)
   172  	}
   173  	bytes1 := buf1.Bytes()
   174  
   175  	ast2, err := Parse(NewFileBase(filename), &buf1, nil, nil, 0)
   176  	if err != nil {
   177  		panic(err)
   178  	}
   179  
   180  	var buf2 bytes.Buffer
   181  	_, err = Fprint(&buf2, ast2, LineForm)
   182  	if err != nil {
   183  		panic(err)
   184  	}
   185  	bytes2 := buf2.Bytes()
   186  
   187  	if bytes.Compare(bytes1, bytes2) != 0 {
   188  		fmt.Printf("--- %s ---\n", filename)
   189  		fmt.Printf("%s\n", bytes1)
   190  		fmt.Println()
   191  
   192  		fmt.Printf("--- %s ---\n", filename)
   193  		fmt.Printf("%s\n", bytes2)
   194  		fmt.Println()
   195  
   196  		t.Error("printed syntax trees do not match")
   197  	}
   198  }
   199  
   200  func TestIssue17697(t *testing.T) {
   201  	_, err := Parse(nil, bytes.NewReader(nil), nil, nil, 0) // return with parser error, don't panic
   202  	if err == nil {
   203  		t.Errorf("no error reported")
   204  	}
   205  }
   206  
   207  func TestParseFile(t *testing.T) {
   208  	_, err := ParseFile("", nil, nil, 0)
   209  	if err == nil {
   210  		t.Error("missing io error")
   211  	}
   212  
   213  	var first error
   214  	_, err = ParseFile("", func(err error) {
   215  		if first == nil {
   216  			first = err
   217  		}
   218  	}, nil, 0)
   219  	if err == nil || first == nil {
   220  		t.Error("missing io error")
   221  	}
   222  	if err != first {
   223  		t.Errorf("got %v; want first error %v", err, first)
   224  	}
   225  }
   226  
   227  // Make sure (PosMax + 1) doesn't overflow when converted to default
   228  // type int (when passed as argument to fmt.Sprintf) on 32bit platforms
   229  // (see test cases below).
   230  var tooLarge int = PosMax + 1
   231  
   232  func TestLineDirectives(t *testing.T) {
   233  	// valid line directives lead to a syntax error after them
   234  	const valid = "syntax error: package statement must be first"
   235  	const filename = "directives.go"
   236  
   237  	for _, test := range []struct {
   238  		src, msg  string
   239  		filename  string
   240  		line, col uint // 1-based; 0 means unknown
   241  	}{
   242  		// ignored //line directives
   243  		{"//\n", valid, filename, 2, 1},            // no directive
   244  		{"//line\n", valid, filename, 2, 1},        // missing colon
   245  		{"//line foo\n", valid, filename, 2, 1},    // missing colon
   246  		{"  //line foo:\n", valid, filename, 2, 1}, // not a line start
   247  		{"//  line foo:\n", valid, filename, 2, 1}, // space between // and line
   248  
   249  		// invalid //line directives with one colon
   250  		{"//line :\n", "invalid line number: ", filename, 1, 9},
   251  		{"//line :x\n", "invalid line number: x", filename, 1, 9},
   252  		{"//line foo :\n", "invalid line number: ", filename, 1, 13},
   253  		{"//line foo:x\n", "invalid line number: x", filename, 1, 12},
   254  		{"//line foo:0\n", "invalid line number: 0", filename, 1, 12},
   255  		{"//line foo:1 \n", "invalid line number: 1 ", filename, 1, 12},
   256  		{"//line foo:-12\n", "invalid line number: -12", filename, 1, 12},
   257  		{"//line C:foo:0\n", "invalid line number: 0", filename, 1, 14},
   258  		{fmt.Sprintf("//line foo:%d\n", tooLarge), fmt.Sprintf("invalid line number: %d", tooLarge), filename, 1, 12},
   259  
   260  		// invalid //line directives with two colons
   261  		{"//line ::\n", "invalid line number: ", filename, 1, 10},
   262  		{"//line ::x\n", "invalid line number: x", filename, 1, 10},
   263  		{"//line foo::123abc\n", "invalid line number: 123abc", filename, 1, 13},
   264  		{"//line foo::0\n", "invalid line number: 0", filename, 1, 13},
   265  		{"//line foo:0:1\n", "invalid line number: 0", filename, 1, 12},
   266  
   267  		{"//line :123:0\n", "invalid column number: 0", filename, 1, 13},
   268  		{"//line foo:123:0\n", "invalid column number: 0", filename, 1, 16},
   269  		{fmt.Sprintf("//line foo:10:%d\n", tooLarge), fmt.Sprintf("invalid column number: %d", tooLarge), filename, 1, 15},
   270  
   271  		// effect of valid //line directives on lines
   272  		{"//line foo:123\n   foo", valid, "foo", 123, 0},
   273  		{"//line  foo:123\n   foo", valid, " foo", 123, 0},
   274  		{"//line foo:123\n//line bar:345\nfoo", valid, "bar", 345, 0},
   275  		{"//line C:foo:123\n", valid, "C:foo", 123, 0},
   276  		{"//line /src/a/a.go:123\n   foo", valid, "/src/a/a.go", 123, 0},
   277  		{"//line :x:1\n", valid, ":x", 1, 0},
   278  		{"//line foo ::1\n", valid, "foo :", 1, 0},
   279  		{"//line foo:123abc:1\n", valid, "foo:123abc", 1, 0},
   280  		{"//line foo :123:1\n", valid, "foo ", 123, 1},
   281  		{"//line ::123\n", valid, ":", 123, 0},
   282  
   283  		// effect of valid //line directives on columns
   284  		{"//line :x:1:10\n", valid, ":x", 1, 10},
   285  		{"//line foo ::1:2\n", valid, "foo :", 1, 2},
   286  		{"//line foo:123abc:1:1000\n", valid, "foo:123abc", 1, 1000},
   287  		{"//line foo :123:1000\n\n", valid, "foo ", 124, 1},
   288  		{"//line ::123:1234\n", valid, ":", 123, 1234},
   289  
   290  		// //line directives with omitted filenames lead to empty filenames
   291  		{"//line :10\n", valid, "", 10, 0},
   292  		{"//line :10:20\n", valid, filename, 10, 20},
   293  		{"//line bar:1\n//line :10\n", valid, "", 10, 0},
   294  		{"//line bar:1\n//line :10:20\n", valid, "bar", 10, 20},
   295  
   296  		// ignored /*line directives
   297  		{"/**/", valid, filename, 1, 5},             // no directive
   298  		{"/*line*/", valid, filename, 1, 9},         // missing colon
   299  		{"/*line foo*/", valid, filename, 1, 13},    // missing colon
   300  		{"  //line foo:*/", valid, filename, 1, 16}, // not a line start
   301  		{"/*  line foo:*/", valid, filename, 1, 16}, // space between // and line
   302  
   303  		// invalid /*line directives with one colon
   304  		{"/*line :*/", "invalid line number: ", filename, 1, 9},
   305  		{"/*line :x*/", "invalid line number: x", filename, 1, 9},
   306  		{"/*line foo :*/", "invalid line number: ", filename, 1, 13},
   307  		{"/*line foo:x*/", "invalid line number: x", filename, 1, 12},
   308  		{"/*line foo:0*/", "invalid line number: 0", filename, 1, 12},
   309  		{"/*line foo:1 */", "invalid line number: 1 ", filename, 1, 12},
   310  		{"/*line C:foo:0*/", "invalid line number: 0", filename, 1, 14},
   311  		{fmt.Sprintf("/*line foo:%d*/", tooLarge), fmt.Sprintf("invalid line number: %d", tooLarge), filename, 1, 12},
   312  
   313  		// invalid /*line directives with two colons
   314  		{"/*line ::*/", "invalid line number: ", filename, 1, 10},
   315  		{"/*line ::x*/", "invalid line number: x", filename, 1, 10},
   316  		{"/*line foo::123abc*/", "invalid line number: 123abc", filename, 1, 13},
   317  		{"/*line foo::0*/", "invalid line number: 0", filename, 1, 13},
   318  		{"/*line foo:0:1*/", "invalid line number: 0", filename, 1, 12},
   319  
   320  		{"/*line :123:0*/", "invalid column number: 0", filename, 1, 13},
   321  		{"/*line foo:123:0*/", "invalid column number: 0", filename, 1, 16},
   322  		{fmt.Sprintf("/*line foo:10:%d*/", tooLarge), fmt.Sprintf("invalid column number: %d", tooLarge), filename, 1, 15},
   323  
   324  		// effect of valid /*line directives on lines
   325  		{"/*line foo:123*/   foo", valid, "foo", 123, 0},
   326  		{"/*line foo:123*/\n//line bar:345\nfoo", valid, "bar", 345, 0},
   327  		{"/*line C:foo:123*/", valid, "C:foo", 123, 0},
   328  		{"/*line /src/a/a.go:123*/   foo", valid, "/src/a/a.go", 123, 0},
   329  		{"/*line :x:1*/", valid, ":x", 1, 0},
   330  		{"/*line foo ::1*/", valid, "foo :", 1, 0},
   331  		{"/*line foo:123abc:1*/", valid, "foo:123abc", 1, 0},
   332  		{"/*line foo :123:10*/", valid, "foo ", 123, 10},
   333  		{"/*line ::123*/", valid, ":", 123, 0},
   334  
   335  		// effect of valid /*line directives on columns
   336  		{"/*line :x:1:10*/", valid, ":x", 1, 10},
   337  		{"/*line foo ::1:2*/", valid, "foo :", 1, 2},
   338  		{"/*line foo:123abc:1:1000*/", valid, "foo:123abc", 1, 1000},
   339  		{"/*line foo :123:1000*/\n", valid, "foo ", 124, 1},
   340  		{"/*line ::123:1234*/", valid, ":", 123, 1234},
   341  
   342  		// /*line directives with omitted filenames lead to the previously used filenames
   343  		{"/*line :10*/", valid, "", 10, 0},
   344  		{"/*line :10:20*/", valid, filename, 10, 20},
   345  		{"//line bar:1\n/*line :10*/", valid, "", 10, 0},
   346  		{"//line bar:1\n/*line :10:20*/", valid, "bar", 10, 20},
   347  	} {
   348  		base := NewFileBase(filename)
   349  		_, err := Parse(base, strings.NewReader(test.src), nil, nil, 0)
   350  		if err == nil {
   351  			t.Errorf("%s: no error reported", test.src)
   352  			continue
   353  		}
   354  		perr, ok := err.(Error)
   355  		if !ok {
   356  			t.Errorf("%s: got %v; want parser error", test.src, err)
   357  			continue
   358  		}
   359  		if msg := perr.Msg; msg != test.msg {
   360  			t.Errorf("%s: got msg = %q; want %q", test.src, msg, test.msg)
   361  		}
   362  
   363  		pos := perr.Pos
   364  		if filename := pos.RelFilename(); filename != test.filename {
   365  			t.Errorf("%s: got filename = %q; want %q", test.src, filename, test.filename)
   366  		}
   367  		if line := pos.RelLine(); line != test.line {
   368  			t.Errorf("%s: got line = %d; want %d", test.src, line, test.line)
   369  		}
   370  		if col := pos.RelCol(); col != test.col {
   371  			t.Errorf("%s: got col = %d; want %d", test.src, col, test.col)
   372  		}
   373  	}
   374  }
   375
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