parser_test.go

Documentation: cmd/compile/internal/syntax

     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)
    50  		}
    51  	}
    52  }
    53  
    54  func TestStdLib(t *testing.T)        { testStdLib(t, 0) }
    55  func TestStdLibGeneric(t *testing.T) { testStdLib(t, AllowGenerics) }
    56  
    57  func testStdLib(t *testing.T, mode Mode) {
    58  	if testing.Short() {
    59  		t.Skip("skipping test in short mode")
    60  	}
    61  
    62  	var skipRx *regexp.Regexp
    63  	if *skip != "" {
    64  		var err error
    65  		skipRx, err = regexp.Compile(*skip)
    66  		if err != nil {
    67  			t.Fatalf("invalid argument for -skip (%v)", err)
    68  		}
    69  	}
    70  
    71  	var m1 runtime.MemStats
    72  	runtime.ReadMemStats(&m1)
    73  	start := time.Now()
    74  
    75  	type parseResult struct {
    76  		filename string
    77  		lines    uint
    78  	}
    79  
    80  	results := make(chan parseResult)
    81  	go func() {
    82  		defer close(results)
    83  		for _, dir := range []string{
    84  			runtime.GOROOT(),
    85  		} {
    86  			walkDirs(t, dir, func(filename string) {
    87  				if skipRx != nil && skipRx.MatchString(filename) {
    88  					// Always report skipped files since regexp
    89  					// typos can lead to surprising results.
    90  					fmt.Printf("skipping %s\n", filename)
    91  					return
    92  				}
    93  				if debug {
    94  					fmt.Printf("parsing %s\n", filename)
    95  				}
    96  				ast, err := ParseFile(filename, nil, nil, mode)
    97  				if err != nil {
    98  					t.Error(err)
    99  					return
   100  				}
   101  				if *verify {
   102  					verifyPrint(t, filename, ast)
   103  				}
   104  				results <- parseResult{filename, ast.EOF.Line()}
   105  			})
   106  		}
   107  	}()
   108  
   109  	var count, lines uint
   110  	for res := range results {
   111  		count++
   112  		lines += res.lines
   113  		if testing.Verbose() {
   114  			fmt.Printf("%5d  %s (%d lines)\n", count, res.filename, res.lines)
   115  		}
   116  	}
   117  
   118  	dt := time.Since(start)
   119  	var m2 runtime.MemStats
   120  	runtime.ReadMemStats(&m2)
   121  	dm := float64(m2.TotalAlloc-m1.TotalAlloc) / 1e6
   122  
   123  	fmt.Printf("parsed %d lines (%d files) in %v (%d lines/s)\n", lines, count, dt, int64(float64(lines)/dt.Seconds()))
   124  	fmt.Printf("allocated %.3fMb (%.3fMb/s)\n", dm, dm/dt.Seconds())
   125  }
   126  
   127  func walkDirs(t *testing.T, dir string, action func(string)) {
   128  	fis, err := ioutil.ReadDir(dir)
   129  	if err != nil {
   130  		t.Error(err)
   131  		return
   132  	}
   133  
   134  	var files, dirs []string
   135  	for _, fi := range fis {
   136  		if fi.Mode().IsRegular() {
   137  			if strings.HasSuffix(fi.Name(), ".go") {
   138  				path := filepath.Join(dir, fi.Name())
   139  				files = append(files, path)
   140  			}
   141  		} else if fi.IsDir() && fi.Name() != "testdata" {
   142  			path := filepath.Join(dir, fi.Name())
   143  			if !strings.HasSuffix(path, string(filepath.Separator)+"test") {
   144  				dirs = append(dirs, path)
   145  			}
   146  		}
   147  	}
   148  
   149  	if *fast {
   150  		var wg sync.WaitGroup
   151  		wg.Add(len(files))
   152  		for _, filename := range files {
   153  			go func(filename string) {
   154  				defer wg.Done()
   155  				action(filename)
   156  			}(filename)
   157  		}
   158  		wg.Wait()
   159  	} else {
   160  		for _, filename := range files {
   161  			action(filename)
   162  		}
   163  	}
   164  
   165  	for _, dir := range dirs {
   166  		walkDirs(t, dir, action)
   167  	}
   168  }
   169  
   170  func verifyPrint(t *testing.T, filename string, ast1 *File) {
   171  	var buf1 bytes.Buffer
   172  	_, err := Fprint(&buf1, ast1, LineForm)
   173  	if err != nil {
   174  		panic(err)
   175  	}
   176  	bytes1 := buf1.Bytes()
   177  
   178  	ast2, err := Parse(NewFileBase(filename), &buf1, nil, nil, 0)
   179  	if err != nil {
   180  		panic(err)
   181  	}
   182  
   183  	var buf2 bytes.Buffer
   184  	_, err = Fprint(&buf2, ast2, LineForm)
   185  	if err != nil {
   186  		panic(err)
   187  	}
   188  	bytes2 := buf2.Bytes()
   189  
   190  	if bytes.Compare(bytes1, bytes2) != 0 {
   191  		fmt.Printf("--- %s ---\n", filename)
   192  		fmt.Printf("%s\n", bytes1)
   193  		fmt.Println()
   194  
   195  		fmt.Printf("--- %s ---\n", filename)
   196  		fmt.Printf("%s\n", bytes2)
   197  		fmt.Println()
   198  
   199  		t.Error("printed syntax trees do not match")
   200  	}
   201  }
   202  
   203  func TestIssue17697(t *testing.T) {
   204  	_, err := Parse(nil, bytes.NewReader(nil), nil, nil, 0) // return with parser error, don't panic
   205  	if err == nil {
   206  		t.Errorf("no error reported")
   207  	}
   208  }
   209  
   210  func TestParseFile(t *testing.T) {
   211  	_, err := ParseFile("", nil, nil, 0)
   212  	if err == nil {
   213  		t.Error("missing io error")
   214  	}
   215  
   216  	var first error
   217  	_, err = ParseFile("", func(err error) {
   218  		if first == nil {
   219  			first = err
   220  		}
   221  	}, nil, 0)
   222  	if err == nil || first == nil {
   223  		t.Error("missing io error")
   224  	}
   225  	if err != first {
   226  		t.Errorf("got %v; want first error %v", err, first)
   227  	}
   228  }
   229  
   230  // Make sure (PosMax + 1) doesn't overflow when converted to default
   231  // type int (when passed as argument to fmt.Sprintf) on 32bit platforms
   232  // (see test cases below).
   233  var tooLarge int = PosMax + 1
   234  
   235  func TestLineDirectives(t *testing.T) {
   236  	// valid line directives lead to a syntax error after them
   237  	const valid = "syntax error: package statement must be first"
   238  	const filename = "directives.go"
   239  
   240  	for _, test := range []struct {
   241  		src, msg  string
   242  		filename  string
   243  		line, col uint // 1-based; 0 means unknown
   244  	}{
   245  		// ignored //line directives
   246  		{"//\n", valid, filename, 2, 1},            // no directive
   247  		{"//line\n", valid, filename, 2, 1},        // missing colon
   248  		{"//line foo\n", valid, filename, 2, 1},    // missing colon
   249  		{"  //line foo:\n", valid, filename, 2, 1}, // not a line start
   250  		{"//  line foo:\n", valid, filename, 2, 1}, // space between // and line
   251  
   252  		// invalid //line directives with one colon
   253  		{"//line :\n", "invalid line number: ", filename, 1, 9},
   254  		{"//line :x\n", "invalid line number: x", filename, 1, 9},
   255  		{"//line foo :\n", "invalid line number: ", filename, 1, 13},
   256  		{"//line foo:x\n", "invalid line number: x", filename, 1, 12},
   257  		{"//line foo:0\n", "invalid line number: 0", filename, 1, 12},
   258  		{"//line foo:1 \n", "invalid line number: 1 ", filename, 1, 12},
   259  		{"//line foo:-12\n", "invalid line number: -12", filename, 1, 12},
   260  		{"//line C:foo:0\n", "invalid line number: 0", filename, 1, 14},
   261  		{fmt.Sprintf("//line foo:%d\n", tooLarge), fmt.Sprintf("invalid line number: %d", tooLarge), filename, 1, 12},
   262  
   263  		// invalid //line directives with two colons
   264  		{"//line ::\n", "invalid line number: ", filename, 1, 10},
   265  		{"//line ::x\n", "invalid line number: x", filename, 1, 10},
   266  		{"//line foo::123abc\n", "invalid line number: 123abc", filename, 1, 13},
   267  		{"//line foo::0\n", "invalid line number: 0", filename, 1, 13},
   268  		{"//line foo:0:1\n", "invalid line number: 0", filename, 1, 12},
   269  
   270  		{"//line :123:0\n", "invalid column number: 0", filename, 1, 13},
   271  		{"//line foo:123:0\n", "invalid column number: 0", filename, 1, 16},
   272  		{fmt.Sprintf("//line foo:10:%d\n", tooLarge), fmt.Sprintf("invalid column number: %d", tooLarge), filename, 1, 15},
   273  
   274  		// effect of valid //line directives on lines
   275  		{"//line foo:123\n   foo", valid, "foo", 123, 0},
   276  		{"//line  foo:123\n   foo", valid, " foo", 123, 0},
   277  		{"//line foo:123\n//line bar:345\nfoo", valid, "bar", 345, 0},
   278  		{"//line C:foo:123\n", valid, "C:foo", 123, 0},
   279  		{"//line /src/a/a.go:123\n   foo", valid, "/src/a/a.go", 123, 0},
   280  		{"//line :x:1\n", valid, ":x", 1, 0},
   281  		{"//line foo ::1\n", valid, "foo :", 1, 0},
   282  		{"//line foo:123abc:1\n", valid, "foo:123abc", 1, 0},
   283  		{"//line foo :123:1\n", valid, "foo ", 123, 1},
   284  		{"//line ::123\n", valid, ":", 123, 0},
   285  
   286  		// effect of valid //line directives on columns
   287  		{"//line :x:1:10\n", valid, ":x", 1, 10},
   288  		{"//line foo ::1:2\n", valid, "foo :", 1, 2},
   289  		{"//line foo:123abc:1:1000\n", valid, "foo:123abc", 1, 1000},
   290  		{"//line foo :123:1000\n\n", valid, "foo ", 124, 1},
   291  		{"//line ::123:1234\n", valid, ":", 123, 1234},
   292  
   293  		// //line directives with omitted filenames lead to empty filenames
   294  		{"//line :10\n", valid, "", 10, 0},
   295  		{"//line :10:20\n", valid, filename, 10, 20},
   296  		{"//line bar:1\n//line :10\n", valid, "", 10, 0},
   297  		{"//line bar:1\n//line :10:20\n", valid, "bar", 10, 20},
   298  
   299  		// ignored /*line directives
   300  		{"/**/", valid, filename, 1, 5},             // no directive
   301  		{"/*line*/", valid, filename, 1, 9},         // missing colon
   302  		{"/*line foo*/", valid, filename, 1, 13},    // missing colon
   303  		{"  //line foo:*/", valid, filename, 1, 16}, // not a line start
   304  		{"/*  line foo:*/", valid, filename, 1, 16}, // space between // and line
   305  
   306  		// invalid /*line directives with one colon
   307  		{"/*line :*/", "invalid line number: ", filename, 1, 9},
   308  		{"/*line :x*/", "invalid line number: x", filename, 1, 9},
   309  		{"/*line foo :*/", "invalid line number: ", filename, 1, 13},
   310  		{"/*line foo:x*/", "invalid line number: x", filename, 1, 12},
   311  		{"/*line foo:0*/", "invalid line number: 0", filename, 1, 12},
   312  		{"/*line foo:1 */", "invalid line number: 1 ", filename, 1, 12},
   313  		{"/*line C:foo:0*/", "invalid line number: 0", filename, 1, 14},
   314  		{fmt.Sprintf("/*line foo:%d*/", tooLarge), fmt.Sprintf("invalid line number: %d", tooLarge), filename, 1, 12},
   315  
   316  		// invalid /*line directives with two colons
   317  		{"/*line ::*/", "invalid line number: ", filename, 1, 10},
   318  		{"/*line ::x*/", "invalid line number: x", filename, 1, 10},
   319  		{"/*line foo::123abc*/", "invalid line number: 123abc", filename, 1, 13},
   320  		{"/*line foo::0*/", "invalid line number: 0", filename, 1, 13},
   321  		{"/*line foo:0:1*/", "invalid line number: 0", filename, 1, 12},
   322  
   323  		{"/*line :123:0*/", "invalid column number: 0", filename, 1, 13},
   324  		{"/*line foo:123:0*/", "invalid column number: 0", filename, 1, 16},
   325  		{fmt.Sprintf("/*line foo:10:%d*/", tooLarge), fmt.Sprintf("invalid column number: %d", tooLarge), filename, 1, 15},
   326  
   327  		// effect of valid /*line directives on lines
   328  		{"/*line foo:123*/   foo", valid, "foo", 123, 0},
   329  		{"/*line foo:123*/\n//line bar:345\nfoo", valid, "bar", 345, 0},
   330  		{"/*line C:foo:123*/", valid, "C:foo", 123, 0},
   331  		{"/*line /src/a/a.go:123*/   foo", valid, "/src/a/a.go", 123, 0},
   332  		{"/*line :x:1*/", valid, ":x", 1, 0},
   333  		{"/*line foo ::1*/", valid, "foo :", 1, 0},
   334  		{"/*line foo:123abc:1*/", valid, "foo:123abc", 1, 0},
   335  		{"/*line foo :123:10*/", valid, "foo ", 123, 10},
   336  		{"/*line ::123*/", valid, ":", 123, 0},
   337  
   338  		// effect of valid /*line directives on columns
   339  		{"/*line :x:1:10*/", valid, ":x", 1, 10},
   340  		{"/*line foo ::1:2*/", valid, "foo :", 1, 2},
   341  		{"/*line foo:123abc:1:1000*/", valid, "foo:123abc", 1, 1000},
   342  		{"/*line foo :123:1000*/\n", valid, "foo ", 124, 1},
   343  		{"/*line ::123:1234*/", valid, ":", 123, 1234},
   344  
   345  		// /*line directives with omitted filenames lead to the previously used filenames
   346  		{"/*line :10*/", valid, "", 10, 0},
   347  		{"/*line :10:20*/", valid, filename, 10, 20},
   348  		{"//line bar:1\n/*line :10*/", valid, "", 10, 0},
   349  		{"//line bar:1\n/*line :10:20*/", valid, "bar", 10, 20},
   350  	} {
   351  		base := NewFileBase(filename)
   352  		_, err := Parse(base, strings.NewReader(test.src), nil, nil, 0)
   353  		if err == nil {
   354  			t.Errorf("%s: no error reported", test.src)
   355  			continue
   356  		}
   357  		perr, ok := err.(Error)
   358  		if !ok {
   359  			t.Errorf("%s: got %v; want parser error", test.src, err)
   360  			continue
   361  		}
   362  		if msg := perr.Msg; msg != test.msg {
   363  			t.Errorf("%s: got msg = %q; want %q", test.src, msg, test.msg)
   364  		}
   365  
   366  		pos := perr.Pos
   367  		if filename := pos.RelFilename(); filename != test.filename {
   368  			t.Errorf("%s: got filename = %q; want %q", test.src, filename, test.filename)
   369  		}
   370  		if line := pos.RelLine(); line != test.line {
   371  			t.Errorf("%s: got line = %d; want %d", test.src, line, test.line)
   372  		}
   373  		if col := pos.RelCol(); col != test.col {
   374  			t.Errorf("%s: got col = %d; want %d", test.src, col, test.col)
   375  		}
   376  	}
   377  }
   378
View as plain text