...
Run Format

Source file src/cmd/vet/testdata/print.go

Documentation: cmd/vet/testdata

     1  // Copyright 2010 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 contains tests for the printf checker.
     6  
     7  // TODO(rsc): The user-defined wrapper tests are commented out
     8  // because they produced too many false positives when vet was
     9  // enabled during go test. See the TODO in ../print.go for a plan
    10  // to fix that; when it's fixed, uncomment the user-defined wrapper tests.
    11  
    12  package testdata
    13  
    14  import (
    15  	"fmt"
    16  	. "fmt"
    17  	"math"
    18  	"os"
    19  	"testing"
    20  	"unsafe" // just for test case printing unsafe.Pointer
    21  	// For testing printf-like functions from external package.
    22  	// "github.com/foobar/externalprintf"
    23  )
    24  
    25  func UnsafePointerPrintfTest() {
    26  	var up unsafe.Pointer
    27  	fmt.Printf("%p, %x %X", up, up, up)
    28  }
    29  
    30  // Error methods that do not satisfy the Error interface and should be checked.
    31  type errorTest1 int
    32  
    33  func (errorTest1) Error(...interface{}) string {
    34  	return "hi"
    35  }
    36  
    37  type errorTest2 int // Analogous to testing's *T type.
    38  func (errorTest2) Error(...interface{}) {
    39  }
    40  
    41  type errorTest3 int
    42  
    43  func (errorTest3) Error() { // No return value.
    44  }
    45  
    46  type errorTest4 int
    47  
    48  func (errorTest4) Error() int { // Different return type.
    49  	return 3
    50  }
    51  
    52  type errorTest5 int
    53  
    54  func (errorTest5) error() { // niladic; don't complain if no args (was bug)
    55  }
    56  
    57  // This function never executes, but it serves as a simple test for the program.
    58  // Test with make test.
    59  func PrintfTests() {
    60  	var b bool
    61  	var i int
    62  	var r rune
    63  	var s string
    64  	var x float64
    65  	var p *int
    66  	var imap map[int]int
    67  	var fslice []float64
    68  	var c complex64
    69  	// Some good format/argtypes
    70  	fmt.Printf("")
    71  	fmt.Printf("%b %b %b", 3, i, x)
    72  	fmt.Printf("%c %c %c %c", 3, i, 'x', r)
    73  	fmt.Printf("%d %d %d", 3, i, imap)
    74  	fmt.Printf("%e %e %e %e", 3e9, x, fslice, c)
    75  	fmt.Printf("%E %E %E %E", 3e9, x, fslice, c)
    76  	fmt.Printf("%f %f %f %f", 3e9, x, fslice, c)
    77  	fmt.Printf("%F %F %F %F", 3e9, x, fslice, c)
    78  	fmt.Printf("%g %g %g %g", 3e9, x, fslice, c)
    79  	fmt.Printf("%G %G %G %G", 3e9, x, fslice, c)
    80  	fmt.Printf("%b %b %b %b", 3e9, x, fslice, c)
    81  	fmt.Printf("%o %o", 3, i)
    82  	fmt.Printf("%p %p", p, nil)
    83  	fmt.Printf("%q %q %q %q", 3, i, 'x', r)
    84  	fmt.Printf("%s %s %s", "hi", s, []byte{65})
    85  	fmt.Printf("%t %t", true, b)
    86  	fmt.Printf("%T %T", 3, i)
    87  	fmt.Printf("%U %U", 3, i)
    88  	fmt.Printf("%v %v", 3, i)
    89  	fmt.Printf("%x %x %x %x", 3, i, "hi", s)
    90  	fmt.Printf("%X %X %X %X", 3, i, "hi", s)
    91  	fmt.Printf("%.*s %d %g", 3, "hi", 23, 2.3)
    92  	fmt.Printf("%s", &stringerv)
    93  	fmt.Printf("%v", &stringerv)
    94  	fmt.Printf("%T", &stringerv)
    95  	fmt.Printf("%s", &embeddedStringerv)
    96  	fmt.Printf("%v", &embeddedStringerv)
    97  	fmt.Printf("%T", &embeddedStringerv)
    98  	fmt.Printf("%v", notstringerv)
    99  	fmt.Printf("%T", notstringerv)
   100  	fmt.Printf("%q", stringerarrayv)
   101  	fmt.Printf("%v", stringerarrayv)
   102  	fmt.Printf("%s", stringerarrayv)
   103  	fmt.Printf("%v", notstringerarrayv)
   104  	fmt.Printf("%T", notstringerarrayv)
   105  	fmt.Printf("%d", new(Formatter))
   106  	fmt.Printf("%*%", 2)               // Ridiculous but allowed.
   107  	fmt.Printf("%s", interface{}(nil)) // Nothing useful we can say.
   108  
   109  	fmt.Printf("%g", 1+2i)
   110  	fmt.Printf("%#e %#E %#f %#F %#g %#G", 1.2, 1.2, 1.2, 1.2, 1.2, 1.2) // OK since Go 1.9
   111  	// Some bad format/argTypes
   112  	fmt.Printf("%b", "hi")                      // ERROR "Printf format %b has arg \x22hi\x22 of wrong type string"
   113  	fmt.Printf("%t", c)                         // ERROR "Printf format %t has arg c of wrong type complex64"
   114  	fmt.Printf("%t", 1+2i)                      // ERROR "Printf format %t has arg 1 \+ 2i of wrong type complex128"
   115  	fmt.Printf("%c", 2.3)                       // ERROR "Printf format %c has arg 2.3 of wrong type float64"
   116  	fmt.Printf("%d", 2.3)                       // ERROR "Printf format %d has arg 2.3 of wrong type float64"
   117  	fmt.Printf("%e", "hi")                      // ERROR "Printf format %e has arg \x22hi\x22 of wrong type string"
   118  	fmt.Printf("%E", true)                      // ERROR "Printf format %E has arg true of wrong type bool"
   119  	fmt.Printf("%f", "hi")                      // ERROR "Printf format %f has arg \x22hi\x22 of wrong type string"
   120  	fmt.Printf("%F", 'x')                       // ERROR "Printf format %F has arg 'x' of wrong type rune"
   121  	fmt.Printf("%g", "hi")                      // ERROR "Printf format %g has arg \x22hi\x22 of wrong type string"
   122  	fmt.Printf("%g", imap)                      // ERROR "Printf format %g has arg imap of wrong type map\[int\]int"
   123  	fmt.Printf("%G", i)                         // ERROR "Printf format %G has arg i of wrong type int"
   124  	fmt.Printf("%o", x)                         // ERROR "Printf format %o has arg x of wrong type float64"
   125  	fmt.Printf("%p", 23)                        // ERROR "Printf format %p has arg 23 of wrong type int"
   126  	fmt.Printf("%q", x)                         // ERROR "Printf format %q has arg x of wrong type float64"
   127  	fmt.Printf("%s", b)                         // ERROR "Printf format %s has arg b of wrong type bool"
   128  	fmt.Printf("%s", byte(65))                  // ERROR "Printf format %s has arg byte\(65\) of wrong type byte"
   129  	fmt.Printf("%t", 23)                        // ERROR "Printf format %t has arg 23 of wrong type int"
   130  	fmt.Printf("%U", x)                         // ERROR "Printf format %U has arg x of wrong type float64"
   131  	fmt.Printf("%x", nil)                       // ERROR "Printf format %x has arg nil of wrong type untyped nil"
   132  	fmt.Printf("%X", 2.3)                       // ERROR "Printf format %X has arg 2.3 of wrong type float64"
   133  	fmt.Printf("%s", stringerv)                 // ERROR "Printf format %s has arg stringerv of wrong type testdata.ptrStringer"
   134  	fmt.Printf("%t", stringerv)                 // ERROR "Printf format %t has arg stringerv of wrong type testdata.ptrStringer"
   135  	fmt.Printf("%s", embeddedStringerv)         // ERROR "Printf format %s has arg embeddedStringerv of wrong type testdata.embeddedStringer"
   136  	fmt.Printf("%t", embeddedStringerv)         // ERROR "Printf format %t has arg embeddedStringerv of wrong type testdata.embeddedStringer"
   137  	fmt.Printf("%q", notstringerv)              // ERROR "Printf format %q has arg notstringerv of wrong type testdata.notstringer"
   138  	fmt.Printf("%t", notstringerv)              // ERROR "Printf format %t has arg notstringerv of wrong type testdata.notstringer"
   139  	fmt.Printf("%t", stringerarrayv)            // ERROR "Printf format %t has arg stringerarrayv of wrong type testdata.stringerarray"
   140  	fmt.Printf("%t", notstringerarrayv)         // ERROR "Printf format %t has arg notstringerarrayv of wrong type testdata.notstringerarray"
   141  	fmt.Printf("%q", notstringerarrayv)         // ERROR "Printf format %q has arg notstringerarrayv of wrong type testdata.notstringerarray"
   142  	fmt.Printf("%d", BoolFormatter(true))       // ERROR "Printf format %d has arg BoolFormatter\(true\) of wrong type testdata.BoolFormatter"
   143  	fmt.Printf("%z", FormatterVal(true))        // correct (the type is responsible for formatting)
   144  	fmt.Printf("%d", FormatterVal(true))        // correct (the type is responsible for formatting)
   145  	fmt.Printf("%s", nonemptyinterface)         // correct (the type is responsible for formatting)
   146  	fmt.Printf("%.*s %d %6g", 3, "hi", 23, 'x') // ERROR "Printf format %6g has arg 'x' of wrong type rune"
   147  	fmt.Println()                               // not an error
   148  	fmt.Println("%s", "hi")                     // ERROR "Println call has possible formatting directive %s"
   149  	fmt.Println("%v", "hi")                     // ERROR "Println call has possible formatting directive %v"
   150  	fmt.Println("0.0%")                         // correct (trailing % couldn't be a formatting directive)
   151  	fmt.Printf("%s", "hi", 3)                   // ERROR "Printf call needs 1 arg but has 2 args"
   152  	_ = fmt.Sprintf("%"+("s"), "hi", 3)         // ERROR "Sprintf call needs 1 arg but has 2 args"
   153  	fmt.Printf("%s%%%d", "hi", 3)               // correct
   154  	fmt.Printf("%08s", "woo")                   // correct
   155  	fmt.Printf("% 8s", "woo")                   // correct
   156  	fmt.Printf("%.*d", 3, 3)                    // correct
   157  	fmt.Printf("%.*d x", 3, 3, 3, 3)            // ERROR "Printf call needs 2 args but has 4 args"
   158  	fmt.Printf("%.*d x", "hi", 3)               // ERROR "Printf format %.*d uses non-int \x22hi\x22 as argument of \*"
   159  	fmt.Printf("%.*d x", i, 3)                  // correct
   160  	fmt.Printf("%.*d x", s, 3)                  // ERROR "Printf format %.\*d uses non-int s as argument of \*"
   161  	fmt.Printf("%*% x", 0.22)                   // ERROR "Printf format %\*% uses non-int 0.22 as argument of \*"
   162  	fmt.Printf("%q %q", multi()...)             // ok
   163  	fmt.Printf("%#q", `blah`)                   // ok
   164  	// printf("now is the time", "buddy")          // no error "printf call has arguments but no formatting directives"
   165  	Printf("now is the time", "buddy") // ERROR "Printf call has arguments but no formatting directives"
   166  	Printf("hi")                       // ok
   167  	const format = "%s %s\n"
   168  	Printf(format, "hi", "there")
   169  	Printf(format, "hi")              // ERROR "Printf format %s reads arg #2, but call has only 1 arg$"
   170  	Printf("%s %d %.3v %q", "str", 4) // ERROR "Printf format %.3v reads arg #3, but call has only 2 args"
   171  	f := new(ptrStringer)
   172  	f.Warn(0, "%s", "hello", 3)           // ERROR "Warn call has possible formatting directive %s"
   173  	f.Warnf(0, "%s", "hello", 3)          // ERROR "Warnf call needs 1 arg but has 2 args"
   174  	f.Warnf(0, "%r", "hello")             // ERROR "Warnf format %r has unknown verb r"
   175  	f.Warnf(0, "%#s", "hello")            // ERROR "Warnf format %#s has unrecognized flag #"
   176  	fmt.Printf("%#s", FormatterVal(true)) // correct (the type is responsible for formatting)
   177  	Printf("d%", 2)                       // ERROR "Printf format % is missing verb at end of string"
   178  	Printf("%d", percentDV)
   179  	Printf("%d", &percentDV)
   180  	Printf("%d", notPercentDV)  // ERROR "Printf format %d has arg notPercentDV of wrong type testdata.notPercentDStruct"
   181  	Printf("%d", &notPercentDV) // ERROR "Printf format %d has arg &notPercentDV of wrong type \*testdata.notPercentDStruct"
   182  	Printf("%p", &notPercentDV) // Works regardless: we print it as a pointer.
   183  	Printf("%s", percentSV)
   184  	Printf("%s", &percentSV)
   185  	// Good argument reorderings.
   186  	Printf("%[1]d", 3)
   187  	Printf("%[1]*d", 3, 1)
   188  	Printf("%[2]*[1]d", 1, 3)
   189  	Printf("%[2]*.[1]*[3]d", 2, 3, 4)
   190  	fmt.Fprintf(os.Stderr, "%[2]*.[1]*[3]d", 2, 3, 4) // Use Fprintf to make sure we count arguments correctly.
   191  	// Bad argument reorderings.
   192  	Printf("%[xd", 3)                      // ERROR "Printf format %\[xd is missing closing \]"
   193  	Printf("%[x]d x", 3)                   // ERROR "Printf format has invalid argument index \[x\]"
   194  	Printf("%[3]*s x", "hi", 2)            // ERROR "Printf format has invalid argument index \[3\]"
   195  	_ = fmt.Sprintf("%[3]d x", 2)          // ERROR "Sprintf format has invalid argument index \[3\]"
   196  	Printf("%[2]*.[1]*[3]d x", 2, "hi", 4) // ERROR "Printf format %\[2]\*\.\[1\]\*\[3\]d uses non-int \x22hi\x22 as argument of \*"
   197  	Printf("%[0]s x", "arg1")              // ERROR "Printf format has invalid argument index \[0\]"
   198  	Printf("%[0]d x", 1)                   // ERROR "Printf format has invalid argument index \[0\]"
   199  	// Something that satisfies the error interface.
   200  	var e error
   201  	fmt.Println(e.Error()) // ok
   202  	// Something that looks like an error interface but isn't, such as the (*T).Error method
   203  	// in the testing package.
   204  	var et1 *testing.T
   205  	et1.Error()        // ok
   206  	et1.Error("hi")    // ok
   207  	et1.Error("%d", 3) // ERROR "Error call has possible formatting directive %d"
   208  	var et3 errorTest3
   209  	et3.Error() // ok, not an error method.
   210  	var et4 errorTest4
   211  	et4.Error() // ok, not an error method.
   212  	var et5 errorTest5
   213  	et5.error() // ok, not an error method.
   214  	// Interfaces can be used with any verb.
   215  	var iface interface {
   216  		ToTheMadness() bool // Method ToTheMadness usually returns false
   217  	}
   218  	fmt.Printf("%f", iface) // ok: fmt treats interfaces as transparent and iface may well have a float concrete type
   219  	// Can't print a function.
   220  	Printf("%d", someFunction) // ERROR "Printf format %d arg someFunction is a func value, not called"
   221  	Printf("%v", someFunction) // ERROR "Printf format %v arg someFunction is a func value, not called"
   222  	Println(someFunction)      // ERROR "Println arg someFunction is a func value, not called"
   223  	Printf("%p", someFunction) // ok: maybe someone wants to see the pointer
   224  	Printf("%T", someFunction) // ok: maybe someone wants to see the type
   225  	// Bug: used to recur forever.
   226  	Printf("%p %x", recursiveStructV, recursiveStructV.next)
   227  	Printf("%p %x", recursiveStruct1V, recursiveStruct1V.next)
   228  	Printf("%p %x", recursiveSliceV, recursiveSliceV)
   229  	Printf("%p %x", recursiveMapV, recursiveMapV)
   230  	// Special handling for Log.
   231  	math.Log(3) // OK
   232  	var t *testing.T
   233  	t.Log("%d", 3) // ERROR "Log call has possible formatting directive %d"
   234  	t.Logf("%d", 3)
   235  	t.Logf("%d", "hi") // ERROR "Logf format %d has arg \x22hi\x22 of wrong type string"
   236  
   237  	// Errorf(1, "%d", 3)    // OK
   238  	// Errorf(1, "%d", "hi") // no error "Errorf format %d has arg \x22hi\x22 of wrong type string"
   239  
   240  	// Multiple string arguments before variadic args
   241  	// errorf("WARNING", "foobar")            // OK
   242  	// errorf("INFO", "s=%s, n=%d", "foo", 1) // OK
   243  	// errorf("ERROR", "%d")                  // no error "errorf format %d reads arg #1, but call has only 0 args"
   244  
   245  	// Printf from external package
   246  	// externalprintf.Printf("%d", 42) // OK
   247  	// externalprintf.Printf("foobar") // OK
   248  	// level := 123
   249  	// externalprintf.Logf(level, "%d", 42)                        // OK
   250  	// externalprintf.Errorf(level, level, "foo %q bar", "foobar") // OK
   251  	// externalprintf.Logf(level, "%d")                            // no error "Logf format %d reads arg #1, but call has only 0 args"
   252  	// var formatStr = "%s %s"
   253  	// externalprintf.Sprintf(formatStr, "a", "b")     // OK
   254  	// externalprintf.Logf(level, formatStr, "a", "b") // OK
   255  
   256  	// user-defined Println-like functions
   257  	ss := &someStruct{}
   258  	ss.Log(someFunction, "foo")          // OK
   259  	ss.Error(someFunction, someFunction) // OK
   260  	ss.Println()                         // OK
   261  	ss.Println(1.234, "foo")             // OK
   262  	ss.Println(1, someFunction)          // no error "Println arg someFunction is a func value, not called"
   263  	ss.log(someFunction)                 // OK
   264  	ss.log(someFunction, "bar", 1.33)    // OK
   265  	ss.log(someFunction, someFunction)   // no error "log arg someFunction is a func value, not called"
   266  
   267  	// indexed arguments
   268  	Printf("%d %[3]d %d %[2]d x", 1, 2, 3, 4)             // OK
   269  	Printf("%d %[0]d %d %[2]d x", 1, 2, 3, 4)             // ERROR "Printf format has invalid argument index \[0\]"
   270  	Printf("%d %[3]d %d %[-2]d x", 1, 2, 3, 4)            // ERROR "Printf format has invalid argument index \[-2\]"
   271  	Printf("%d %[3]d %d %[2234234234234]d x", 1, 2, 3, 4) // ERROR "Printf format has invalid argument index \[2234234234234\]"
   272  	Printf("%d %[3]d %-10d %[2]d x", 1, 2, 3)             // ERROR "Printf format %-10d reads arg #4, but call has only 3 args"
   273  	Printf("%[1][3]d x", 1, 2)                            // ERROR "Printf format %\[1\]\[ has unknown verb \["
   274  	Printf("%[1]d x", 1, 2)                               // OK
   275  	Printf("%d %[3]d %d %[2]d x", 1, 2, 3, 4, 5)          // OK
   276  
   277  	// wrote Println but meant Fprintln
   278  	Printf("%p\n", os.Stdout)   // OK
   279  	Println(os.Stdout, "hello") // ERROR "Println does not take io.Writer but has first arg os.Stdout"
   280  
   281  	Printf(someString(), "hello") // OK
   282  
   283  }
   284  
   285  func someString() string { return "X" }
   286  
   287  type someStruct struct{}
   288  
   289  // Log is non-variadic user-define Println-like function.
   290  // Calls to this func must be skipped when checking
   291  // for Println-like arguments.
   292  func (ss *someStruct) Log(f func(), s string) {}
   293  
   294  // Error is variadic user-define Println-like function.
   295  // Calls to this func mustn't be checked for Println-like arguments,
   296  // since variadic arguments type isn't interface{}.
   297  func (ss *someStruct) Error(args ...func()) {}
   298  
   299  // Println is variadic user-defined Println-like function.
   300  // Calls to this func must be checked for Println-like arguments.
   301  func (ss *someStruct) Println(args ...interface{}) {}
   302  
   303  // log is variadic user-defined Println-like function.
   304  // Calls to this func must be checked for Println-like arguments.
   305  func (ss *someStruct) log(f func(), args ...interface{}) {}
   306  
   307  // A function we use as a function value; it has no other purpose.
   308  func someFunction() {}
   309  
   310  /*
   311  // Printf is used by the test so we must declare it.
   312  func Printf(format string, args ...interface{}) {
   313  	panic("don't call - testing only")
   314  }
   315  
   316  // Println is used by the test so we must declare it.
   317  func Println(args ...interface{}) {
   318  	panic("don't call - testing only")
   319  }
   320  
   321  // Logf is used by the test so we must declare it.
   322  func Logf(format string, args ...interface{}) {
   323  	panic("don't call - testing only")
   324  }
   325  
   326  // Log is used by the test so we must declare it.
   327  func Log(args ...interface{}) {
   328  	panic("don't call - testing only")
   329  }
   330  */
   331  
   332  // printf is used by the test so we must declare it.
   333  func printf(format string, args ...interface{}) {
   334  	panic("don't call - testing only")
   335  }
   336  
   337  /*
   338  // Errorf is used by the test for a case in which the first parameter
   339  // is not a format string.
   340  func Errorf(i int, format string, args ...interface{}) {
   341  	panic("don't call - testing only")
   342  }
   343  
   344  // errorf is used by the test for a case in which the function accepts multiple
   345  // string parameters before variadic arguments
   346  func errorf(level, format string, args ...interface{}) {
   347  	panic("don't call - testing only")
   348  }
   349  */
   350  
   351  // multi is used by the test.
   352  func multi() []interface{} {
   353  	panic("don't call - testing only")
   354  }
   355  
   356  type stringer int
   357  
   358  func (stringer) String() string { return "string" }
   359  
   360  type ptrStringer float64
   361  
   362  var stringerv ptrStringer
   363  
   364  func (*ptrStringer) String() string {
   365  	return "string"
   366  }
   367  
   368  func (*ptrStringer) Warn(int, ...interface{}) string {
   369  	return "warn"
   370  }
   371  
   372  func (*ptrStringer) Warnf(int, string, ...interface{}) string {
   373  	return "warnf"
   374  }
   375  
   376  type embeddedStringer struct {
   377  	foo string
   378  	ptrStringer
   379  	bar int
   380  }
   381  
   382  var embeddedStringerv embeddedStringer
   383  
   384  type notstringer struct {
   385  	f float64
   386  }
   387  
   388  var notstringerv notstringer
   389  
   390  type stringerarray [4]float64
   391  
   392  func (stringerarray) String() string {
   393  	return "string"
   394  }
   395  
   396  var stringerarrayv stringerarray
   397  
   398  type notstringerarray [4]float64
   399  
   400  var notstringerarrayv notstringerarray
   401  
   402  var nonemptyinterface = interface {
   403  	f()
   404  }(nil)
   405  
   406  // A data type we can print with "%d".
   407  type percentDStruct struct {
   408  	a int
   409  	b []byte
   410  	c *float64
   411  }
   412  
   413  var percentDV percentDStruct
   414  
   415  // A data type we cannot print correctly with "%d".
   416  type notPercentDStruct struct {
   417  	a int
   418  	b []byte
   419  	c bool
   420  }
   421  
   422  var notPercentDV notPercentDStruct
   423  
   424  // A data type we can print with "%s".
   425  type percentSStruct struct {
   426  	a string
   427  	b []byte
   428  	C stringerarray
   429  }
   430  
   431  var percentSV percentSStruct
   432  
   433  type recursiveStringer int
   434  
   435  func (s recursiveStringer) String() string {
   436  	_ = fmt.Sprintf("%d", s)
   437  	_ = fmt.Sprintf("%#v", s)
   438  	_ = fmt.Sprintf("%v", s)  // ERROR "Sprintf format %v with arg s causes recursive String method call"
   439  	_ = fmt.Sprintf("%v", &s) // ERROR "Sprintf format %v with arg &s causes recursive String method call"
   440  	_ = fmt.Sprintf("%T", s)  // ok; does not recursively call String
   441  	return fmt.Sprintln(s)    // ERROR "Sprintln arg s causes recursive call to String method"
   442  }
   443  
   444  type recursivePtrStringer int
   445  
   446  func (p *recursivePtrStringer) String() string {
   447  	_ = fmt.Sprintf("%v", *p)
   448  	_ = fmt.Sprint(&p)     // ok; prints address
   449  	return fmt.Sprintln(p) // ERROR "Sprintln arg p causes recursive call to String method"
   450  }
   451  
   452  type BoolFormatter bool
   453  
   454  func (*BoolFormatter) Format(fmt.State, rune) {
   455  }
   456  
   457  // Formatter with value receiver
   458  type FormatterVal bool
   459  
   460  func (FormatterVal) Format(fmt.State, rune) {
   461  }
   462  
   463  type RecursiveSlice []RecursiveSlice
   464  
   465  var recursiveSliceV = &RecursiveSlice{}
   466  
   467  type RecursiveMap map[int]RecursiveMap
   468  
   469  var recursiveMapV = make(RecursiveMap)
   470  
   471  type RecursiveStruct struct {
   472  	next *RecursiveStruct
   473  }
   474  
   475  var recursiveStructV = &RecursiveStruct{}
   476  
   477  type RecursiveStruct1 struct {
   478  	next *RecursiveStruct2
   479  }
   480  
   481  type RecursiveStruct2 struct {
   482  	next *RecursiveStruct1
   483  }
   484  
   485  var recursiveStruct1V = &RecursiveStruct1{}
   486  
   487  type unexportedInterface struct {
   488  	f interface{}
   489  }
   490  
   491  // Issue 17798: unexported ptrStringer cannot be formatted.
   492  type unexportedStringer struct {
   493  	t ptrStringer
   494  }
   495  type unexportedStringerOtherFields struct {
   496  	s string
   497  	t ptrStringer
   498  	S string
   499  }
   500  
   501  // Issue 17798: unexported error cannot be formatted.
   502  type unexportedError struct {
   503  	e error
   504  }
   505  type unexportedErrorOtherFields struct {
   506  	s string
   507  	e error
   508  	S string
   509  }
   510  
   511  type errorer struct{}
   512  
   513  func (e errorer) Error() string { return "errorer" }
   514  
   515  type unexportedCustomError struct {
   516  	e errorer
   517  }
   518  
   519  type errorInterface interface {
   520  	error
   521  	ExtraMethod()
   522  }
   523  
   524  type unexportedErrorInterface struct {
   525  	e errorInterface
   526  }
   527  
   528  func UnexportedStringerOrError() {
   529  	fmt.Printf("%s", unexportedInterface{"foo"}) // ok; prints {foo}
   530  	fmt.Printf("%s", unexportedInterface{3})     // ok; we can't see the problem
   531  
   532  	us := unexportedStringer{}
   533  	fmt.Printf("%s", us)  // ERROR "Printf format %s has arg us of wrong type testdata.unexportedStringer"
   534  	fmt.Printf("%s", &us) // ERROR "Printf format %s has arg &us of wrong type [*]testdata.unexportedStringer"
   535  
   536  	usf := unexportedStringerOtherFields{
   537  		s: "foo",
   538  		S: "bar",
   539  	}
   540  	fmt.Printf("%s", usf)  // ERROR "Printf format %s has arg usf of wrong type testdata.unexportedStringerOtherFields"
   541  	fmt.Printf("%s", &usf) // ERROR "Printf format %s has arg &usf of wrong type [*]testdata.unexportedStringerOtherFields"
   542  
   543  	ue := unexportedError{
   544  		e: &errorer{},
   545  	}
   546  	fmt.Printf("%s", ue)  // ERROR "Printf format %s has arg ue of wrong type testdata.unexportedError"
   547  	fmt.Printf("%s", &ue) // ERROR "Printf format %s has arg &ue of wrong type [*]testdata.unexportedError"
   548  
   549  	uef := unexportedErrorOtherFields{
   550  		s: "foo",
   551  		e: &errorer{},
   552  		S: "bar",
   553  	}
   554  	fmt.Printf("%s", uef)  // ERROR "Printf format %s has arg uef of wrong type testdata.unexportedErrorOtherFields"
   555  	fmt.Printf("%s", &uef) // ERROR "Printf format %s has arg &uef of wrong type [*]testdata.unexportedErrorOtherFields"
   556  
   557  	uce := unexportedCustomError{
   558  		e: errorer{},
   559  	}
   560  	fmt.Printf("%s", uce) // ERROR "Printf format %s has arg uce of wrong type testdata.unexportedCustomError"
   561  
   562  	uei := unexportedErrorInterface{}
   563  	fmt.Printf("%s", uei)       // ERROR "Printf format %s has arg uei of wrong type testdata.unexportedErrorInterface"
   564  	fmt.Println("foo\n", "bar") // not an error
   565  
   566  	fmt.Println("foo\n")  // ERROR "Println arg list ends with redundant newline"
   567  	fmt.Println("foo\\n") // not an error
   568  	fmt.Println(`foo\n`)  // not an error
   569  
   570  	intSlice := []int{3, 4}
   571  	fmt.Printf("%s", intSlice) // ERROR "Printf format %s has arg intSlice of wrong type \[\]int"
   572  	nonStringerArray := [1]unexportedStringer{{}}
   573  	fmt.Printf("%s", nonStringerArray)  // ERROR "Printf format %s has arg nonStringerArray of wrong type \[1\]testdata.unexportedStringer"
   574  	fmt.Printf("%s", []stringer{3, 4})  // not an error
   575  	fmt.Printf("%s", [2]stringer{3, 4}) // not an error
   576  }
   577  
   578  // TODO: Disable complaint about '0' for Go 1.10. To be fixed properly in 1.11.
   579  // See issues 23598 and 23605.
   580  func DisableErrorForFlag0() {
   581  	fmt.Printf("%0t", true)
   582  }
   583  

View as plain text