package assert
import (
"bufio"
"bytes"
"encoding/json"
"errors"
"fmt"
"math"
"os"
"reflect"
"regexp"
"runtime"
"strings"
"time"
"unicode"
"unicode/utf8"
"github.com/davecgh/go-spew/spew"
"github.com/pmezard/go-difflib/difflib"
)
//go:generate go run ../_codegen/main.go -output-package=assert -template=assertion_format.go.tmpl
// TestingT is an interface wrapper around *testing.T
type TestingT interface {
Errorf ( format string , args ... interface { } )
}
// Comparison a custom function that returns true on success and false on failure
type Comparison func ( ) ( success bool )
/ *
Helper functions
* /
// ObjectsAreEqual determines if two objects are considered equal.
//
// This function does no assertion of any kind.
func ObjectsAreEqual ( expected , actual interface { } ) bool {
if expected == nil || actual == nil {
return expected == actual
}
if exp , ok := expected . ( [ ] byte ) ; ok {
act , ok := actual . ( [ ] byte )
if ! ok {
return false
} else if exp == nil || act == nil {
return exp == nil && act == nil
}
return bytes . Equal ( exp , act )
}
return reflect . DeepEqual ( expected , actual )
}
// ObjectsAreEqualValues gets whether two objects are equal, or if their
// values are equal.
func ObjectsAreEqualValues ( expected , actual interface { } ) bool {
if ObjectsAreEqual ( expected , actual ) {
return true
}
actualType := reflect . TypeOf ( actual )
if actualType == nil {
return false
}
expectedValue := reflect . ValueOf ( expected )
if expectedValue . IsValid ( ) && expectedValue . Type ( ) . ConvertibleTo ( actualType ) {
// Attempt comparison after type conversion
return reflect . DeepEqual ( expectedValue . Convert ( actualType ) . Interface ( ) , actual )
}
return false
}
/ * CallerInfo is necessary because the assert functions use the testing object
internally , causing it to print the file : line of the assert method , rather than where
the problem actually occurred in calling code . * /
// CallerInfo returns an array of strings containing the file and line number
// of each stack frame leading from the current test to the assert call that
// failed.
func CallerInfo ( ) [ ] string {
pc := uintptr ( 0 )
file := ""
line := 0
ok := false
name := ""
callers := [ ] string { }
for i := 0 ; ; i ++ {
pc , file , line , ok = runtime . Caller ( i )
if ! ok {
// The breaks below failed to terminate the loop, and we ran off the
// end of the call stack.
break
}
// This is a huge edge case, but it will panic if this is the case, see #180
if file == "<autogenerated>" {
break
}
f := runtime . FuncForPC ( pc )
if f == nil {
break
}
name = f . Name ( )
// testing.tRunner is the standard library function that calls
// tests. Subtests are called directly by tRunner, without going through
// the Test/Benchmark/Example function that contains the t.Run calls, so
// with subtests we should break when we hit tRunner, without adding it
// to the list of callers.
if name == "testing.tRunner" {
break
}
parts := strings . Split ( file , "/" )
file = parts [ len ( parts ) - 1 ]
if len ( parts ) > 1 {
dir := parts [ len ( parts ) - 2 ]
if ( dir != "assert" && dir != "mock" && dir != "require" ) || file == "mock_test.go" {
callers = append ( callers , fmt . Sprintf ( "%s:%d" , file , line ) )
}
}
// Drop the package
segments := strings . Split ( name , "." )
name = segments [ len ( segments ) - 1 ]
if isTest ( name , "Test" ) ||
isTest ( name , "Benchmark" ) ||
isTest ( name , "Example" ) {
break
}
}
return callers
}
// Stolen from the `go test` tool.
// isTest tells whether name looks like a test (or benchmark, according to prefix).
// It is a Test (say) if there is a character after Test that is not a lower-case letter.
// We don't want TesticularCancer.
func isTest ( name , prefix string ) bool {
if ! strings . HasPrefix ( name , prefix ) {
return false
}
if len ( name ) == len ( prefix ) { // "Test" is ok
return true
}
rune , _ := utf8 . DecodeRuneInString ( name [ len ( prefix ) : ] )
return ! unicode . IsLower ( rune )
}
// getWhitespaceString returns a string that is long enough to overwrite the default
// output from the go testing framework.
func getWhitespaceString ( ) string {
_ , file , line , ok := runtime . Caller ( 1 )
if ! ok {
return ""
}
parts := strings . Split ( file , "/" )
file = parts [ len ( parts ) - 1 ]
return strings . Repeat ( " " , len ( fmt . Sprintf ( "%s:%d: " , file , line ) ) )
}
func messageFromMsgAndArgs ( msgAndArgs ... interface { } ) string {
if len ( msgAndArgs ) == 0 || msgAndArgs == nil {
return ""
}
if len ( msgAndArgs ) == 1 {
return msgAndArgs [ 0 ] . ( string )
}
if len ( msgAndArgs ) > 1 {
return fmt . Sprintf ( msgAndArgs [ 0 ] . ( string ) , msgAndArgs [ 1 : ] ... )
}
return ""
}
// Aligns the provided message so that all lines after the first line start at the same location as the first line.
// Assumes that the first line starts at the correct location (after carriage return, tab, label, spacer and tab).
// The longestLabelLen parameter specifies the length of the longest label in the output (required becaues this is the
// basis on which the alignment occurs).
func indentMessageLines ( message string , longestLabelLen int ) string {
outBuf := new ( bytes . Buffer )
for i , scanner := 0 , bufio . NewScanner ( strings . NewReader ( message ) ) ; scanner . Scan ( ) ; i ++ {
// no need to align first line because it starts at the correct location (after the label)
if i != 0 {
// append alignLen+1 spaces to align with "{{longestLabel}}:" before adding tab
outBuf . WriteString ( "\n\r\t" + strings . Repeat ( " " , longestLabelLen + 1 ) + "\t" )
}
outBuf . WriteString ( scanner . Text ( ) )
}
return outBuf . String ( )
}
type failNower interface {
FailNow ( )
}
// FailNow fails test
func FailNow ( t TestingT , failureMessage string , msgAndArgs ... interface { } ) bool {
Fail ( t , failureMessage , msgAndArgs ... )
// We cannot extend TestingT with FailNow() and
// maintain backwards compatibility, so we fallback
// to panicking when FailNow is not available in
// TestingT.
// See issue #263
if t , ok := t . ( failNower ) ; ok {
t . FailNow ( )
} else {
panic ( "test failed and t is missing `FailNow()`" )
}
return false
}
// Fail reports a failure through
func Fail ( t TestingT , failureMessage string , msgAndArgs ... interface { } ) bool {
content := [ ] labeledContent {
{ "Error Trace" , strings . Join ( CallerInfo ( ) , "\n\r\t\t\t" ) } ,
{ "Error" , failureMessage } ,
}
// Add test name if the Go version supports it
if n , ok := t . ( interface {
Name ( ) string
} ) ; ok {
content = append ( content , labeledContent { "Test" , n . Name ( ) } )
}
message := messageFromMsgAndArgs ( msgAndArgs ... )
if len ( message ) > 0 {
content = append ( content , labeledContent { "Messages" , message } )
}
t . Errorf ( "%s" , "\r" + getWhitespaceString ( ) + labeledOutput ( content ... ) )
return false
}
type labeledContent struct {
label string
content string
}
// labeledOutput returns a string consisting of the provided labeledContent. Each labeled output is appended in the following manner:
//
// \r\t{{label}}:{{align_spaces}}\t{{content}}\n
//
// The initial carriage return is required to undo/erase any padding added by testing.T.Errorf. The "\t{{label}}:" is for the label.
// If a label is shorter than the longest label provided, padding spaces are added to make all the labels match in length. Once this
// alignment is achieved, "\t{{content}}\n" is added for the output.
//
// If the content of the labeledOutput contains line breaks, the subsequent lines are aligned so that they start at the same location as the first line.
func labeledOutput ( content ... labeledContent ) string {
longestLabel := 0
for _ , v := range content {
if len ( v . label ) > longestLabel {
longestLabel = len ( v . label )
}
}
var output string
for _ , v := range content {
output += "\r\t" + v . label + ":" + strings . Repeat ( " " , longestLabel - len ( v . label ) ) + "\t" + indentMessageLines ( v . content , longestLabel ) + "\n"
}
return output
}
// Implements asserts that an object is implemented by the specified interface.
//
// assert.Implements(t, (*MyInterface)(nil), new(MyObject))
func Implements ( t TestingT , interfaceObject interface { } , object interface { } , msgAndArgs ... interface { } ) bool {
interfaceType := reflect . TypeOf ( interfaceObject ) . Elem ( )
if object == nil {
return Fail ( t , fmt . Sprintf ( "Cannot check if nil implements %v" , interfaceType ) , msgAndArgs ... )
}
if ! reflect . TypeOf ( object ) . Implements ( interfaceType ) {
return Fail ( t , fmt . Sprintf ( "%T must implement %v" , object , interfaceType ) , msgAndArgs ... )
}
return true
}
// IsType asserts that the specified objects are of the same type.
func IsType ( t TestingT , expectedType interface { } , object interface { } , msgAndArgs ... interface { } ) bool {
if ! ObjectsAreEqual ( reflect . TypeOf ( object ) , reflect . TypeOf ( expectedType ) ) {
return Fail ( t , fmt . Sprintf ( "Object expected to be of type %v, but was %v" , reflect . TypeOf ( expectedType ) , reflect . TypeOf ( object ) ) , msgAndArgs ... )
}
return true
}
// Equal asserts that two objects are equal.
//
// assert.Equal(t, 123, 123)
//
// Pointer variable equality is determined based on the equality of the
// referenced values (as opposed to the memory addresses). Function equality
// cannot be determined and will always fail.
func Equal ( t TestingT , expected , actual interface { } , msgAndArgs ... interface { } ) bool {
if err := validateEqualArgs ( expected , actual ) ; err != nil {
return Fail ( t , fmt . Sprintf ( "Invalid operation: %#v == %#v (%s)" ,
expected , actual , err ) , msgAndArgs ... )
}
if ! ObjectsAreEqual ( expected , actual ) {
diff := diff ( expected , actual )
expected , actual = formatUnequalValues ( expected , actual )
return Fail ( t , fmt . Sprintf ( "Not equal: \n" +
"expected: %s\n" +
"actual : %s%s" , expected , actual , diff ) , msgAndArgs ... )
}
return true
}
// formatUnequalValues takes two values of arbitrary types and returns string
// representations appropriate to be presented to the user.
//
// If the values are not of like type, the returned strings will be prefixed
// with the type name, and the value will be enclosed in parenthesis similar
// to a type conversion in the Go grammar.
func formatUnequalValues ( expected , actual interface { } ) ( e string , a string ) {
if reflect . TypeOf ( expected ) != reflect . TypeOf ( actual ) {
return fmt . Sprintf ( "%T(%#v)" , expected , expected ) ,
fmt . Sprintf ( "%T(%#v)" , actual , actual )
}
return fmt . Sprintf ( "%#v" , expected ) ,
fmt . Sprintf ( "%#v" , actual )
}
// EqualValues asserts that two objects are equal or convertable to the same types
// and equal.
//
// assert.EqualValues(t, uint32(123), int32(123))
func EqualValues ( t TestingT , expected , actual interface { } , msgAndArgs ... interface { } ) bool {
if ! ObjectsAreEqualValues ( expected , actual ) {
diff := diff ( expected , actual )
expected , actual = formatUnequalValues ( expected , actual )
return Fail ( t , fmt . Sprintf ( "Not equal: \n" +
"expected: %s\n" +
"actual : %s%s" , expected , actual , diff ) , msgAndArgs ... )
}
return true
}
// Exactly asserts that two objects are equal in value and type.
//
// assert.Exactly(t, int32(123), int64(123))
func Exactly ( t TestingT , expected , actual interface { } , msgAndArgs ... interface { } ) bool {
aType := reflect . TypeOf ( expected )
bType := reflect . TypeOf ( actual )
if aType != bType {
return Fail ( t , fmt . Sprintf ( "Types expected to match exactly\n\r\t%v != %v" , aType , bType ) , msgAndArgs ... )
}
return Equal ( t , expected , actual , msgAndArgs ... )
}
// NotNil asserts that the specified object is not nil.
//
// assert.NotNil(t, err)
func NotNil ( t TestingT , object interface { } , msgAndArgs ... interface { } ) bool {
if ! isNil ( object ) {
return true
}
return Fail ( t , "Expected value not to be nil." , msgAndArgs ... )
}
// isNil checks if a specified object is nil or not, without Failing.
func isNil ( object interface { } ) bool {
if object == nil {
return true
}
value := reflect . ValueOf ( object )
kind := value . Kind ( )
if kind >= reflect . Chan && kind <= reflect . Slice && value . IsNil ( ) {
return true
}
return false
}
// Nil asserts that the specified object is nil.
//
// assert.Nil(t, err)
func Nil ( t TestingT , object interface { } , msgAndArgs ... interface { } ) bool {
if isNil ( object ) {
return true
}
return Fail ( t , fmt . Sprintf ( "Expected nil, but got: %#v" , object ) , msgAndArgs ... )
}
// isEmpty gets whether the specified object is considered empty or not.
func isEmpty ( object interface { } ) bool {
// get nil case out of the way
if object == nil {
return true
}
objValue := reflect . ValueOf ( object )
switch objValue . Kind ( ) {
// collection types are empty when they have no element
case reflect . Array , reflect . Chan , reflect . Map , reflect . Slice :
return objValue . Len ( ) == 0
// pointers are empty if nil or if the value they point to is empty
case reflect . Ptr :
if objValue . IsNil ( ) {
return true
}
deref := objValue . Elem ( ) . Interface ( )
return isEmpty ( deref )
// for all other types, compare against the zero value
default :
zero := reflect . Zero ( objValue . Type ( ) )
return reflect . DeepEqual ( object , zero . Interface ( ) )
}
}
// Empty asserts that the specified object is empty. I.e. nil, "", false, 0 or either
// a slice or a channel with len == 0.
//
// assert.Empty(t, obj)
func Empty ( t TestingT , object interface { } , msgAndArgs ... interface { } ) bool {
pass := isEmpty ( object )
if ! pass {
Fail ( t , fmt . Sprintf ( "Should be empty, but was %v" , object ) , msgAndArgs ... )
}
return pass
}
// NotEmpty asserts that the specified object is NOT empty. I.e. not nil, "", false, 0 or either
// a slice or a channel with len == 0.
//
// if assert.NotEmpty(t, obj) {
// assert.Equal(t, "two", obj[1])
// }
func NotEmpty ( t TestingT , object interface { } , msgAndArgs ... interface { } ) bool {
pass := ! isEmpty ( object )
if ! pass {
Fail ( t , fmt . Sprintf ( "Should NOT be empty, but was %v" , object ) , msgAndArgs ... )
}
return pass
}
// getLen try to get length of object.
// return (false, 0) if impossible.
func getLen ( x interface { } ) ( ok bool , length int ) {
v := reflect . ValueOf ( x )
defer func ( ) {
if e := recover ( ) ; e != nil {
ok = false
}
} ( )
return true , v . Len ( )
}
// Len asserts that the specified object has specific length.
// Len also fails if the object has a type that len() not accept.
//
// assert.Len(t, mySlice, 3)
func Len ( t TestingT , object interface { } , length int , msgAndArgs ... interface { } ) bool {
ok , l := getLen ( object )
if ! ok {
return Fail ( t , fmt . Sprintf ( "\"%s\" could not be applied builtin len()" , object ) , msgAndArgs ... )
}
if l != length {
return Fail ( t , fmt . Sprintf ( "\"%s\" should have %d item(s), but has %d" , object , length , l ) , msgAndArgs ... )
}
return true
}
// True asserts that the specified value is true.
//
// assert.True(t, myBool)
func True ( t TestingT , value bool , msgAndArgs ... interface { } ) bool {
if value != true {
return Fail ( t , "Should be true" , msgAndArgs ... )
}
return true
}
// False asserts that the specified value is false.
//
// assert.False(t, myBool)
func False ( t TestingT , value bool , msgAndArgs ... interface { } ) bool {
if value != false {
return Fail ( t , "Should be false" , msgAndArgs ... )
}
return true
}
// NotEqual asserts that the specified values are NOT equal.
//
// assert.NotEqual(t, obj1, obj2)
//
// Pointer variable equality is determined based on the equality of the
// referenced values (as opposed to the memory addresses).
func NotEqual ( t TestingT , expected , actual interface { } , msgAndArgs ... interface { } ) bool {
if err := validateEqualArgs ( expected , actual ) ; err != nil {
return Fail ( t , fmt . Sprintf ( "Invalid operation: %#v != %#v (%s)" ,
expected , actual , err ) , msgAndArgs ... )
}
if ObjectsAreEqual ( expected , actual ) {
return Fail ( t , fmt . Sprintf ( "Should not be: %#v\n" , actual ) , msgAndArgs ... )
}
return true
}
// containsElement try loop over the list check if the list includes the element.
// return (false, false) if impossible.
// return (true, false) if element was not found.
// return (true, true) if element was found.
func includeElement ( list interface { } , element interface { } ) ( ok , found bool ) {
listValue := reflect . ValueOf ( list )
elementValue := reflect . ValueOf ( element )
defer func ( ) {
if e := recover ( ) ; e != nil {
ok = false
found = false
}
} ( )
if reflect . TypeOf ( list ) . Kind ( ) == reflect . String {
return true , strings . Contains ( listValue . String ( ) , elementValue . String ( ) )
}
if reflect . TypeOf ( list ) . Kind ( ) == reflect . Map {
mapKeys := listValue . MapKeys ( )
for i := 0 ; i < len ( mapKeys ) ; i ++ {
if ObjectsAreEqual ( mapKeys [ i ] . Interface ( ) , element ) {
return true , true
}
}
return true , false
}
for i := 0 ; i < listValue . Len ( ) ; i ++ {
if ObjectsAreEqual ( listValue . Index ( i ) . Interface ( ) , element ) {
return true , true
}
}
return true , false
}
// Contains asserts that the specified string, list(array, slice...) or map contains the
// specified substring or element.
//
// assert.Contains(t, "Hello World", "World")
// assert.Contains(t, ["Hello", "World"], "World")
// assert.Contains(t, {"Hello": "World"}, "Hello")
func Contains ( t TestingT , s , contains interface { } , msgAndArgs ... interface { } ) bool {
ok , found := includeElement ( s , contains )
if ! ok {
return Fail ( t , fmt . Sprintf ( "\"%s\" could not be applied builtin len()" , s ) , msgAndArgs ... )
}
if ! found {
return Fail ( t , fmt . Sprintf ( "\"%s\" does not contain \"%s\"" , s , contains ) , msgAndArgs ... )
}
return true
}
// NotContains asserts that the specified string, list(array, slice...) or map does NOT contain the
// specified substring or element.
//
// assert.NotContains(t, "Hello World", "Earth")
// assert.NotContains(t, ["Hello", "World"], "Earth")
// assert.NotContains(t, {"Hello": "World"}, "Earth")
func NotContains ( t TestingT , s , contains interface { } , msgAndArgs ... interface { } ) bool {
ok , found := includeElement ( s , contains )
if ! ok {
return Fail ( t , fmt . Sprintf ( "\"%s\" could not be applied builtin len()" , s ) , msgAndArgs ... )
}
if found {
return Fail ( t , fmt . Sprintf ( "\"%s\" should not contain \"%s\"" , s , contains ) , msgAndArgs ... )
}
return true
}
// Subset asserts that the specified list(array, slice...) contains all
// elements given in the specified subset(array, slice...).
//
// assert.Subset(t, [1, 2, 3], [1, 2], "But [1, 2, 3] does contain [1, 2]")
func Subset ( t TestingT , list , subset interface { } , msgAndArgs ... interface { } ) ( ok bool ) {
if subset == nil {
return true // we consider nil to be equal to the nil set
}
subsetValue := reflect . ValueOf ( subset )
defer func ( ) {
if e := recover ( ) ; e != nil {
ok = false
}
} ( )
listKind := reflect . TypeOf ( list ) . Kind ( )
subsetKind := reflect . TypeOf ( subset ) . Kind ( )
if listKind != reflect . Array && listKind != reflect . Slice {
return Fail ( t , fmt . Sprintf ( "%q has an unsupported type %s" , list , listKind ) , msgAndArgs ... )
}
if subsetKind != reflect . Array && subsetKind != reflect . Slice {
return Fail ( t , fmt . Sprintf ( "%q has an unsupported type %s" , subset , subsetKind ) , msgAndArgs ... )
}
for i := 0 ; i < subsetValue . Len ( ) ; i ++ {
element := subsetValue . Index ( i ) . Interface ( )
ok , found := includeElement ( list , element )
if ! ok {
return Fail ( t , fmt . Sprintf ( "\"%s\" could not be applied builtin len()" , list ) , msgAndArgs ... )
}
if ! found {
return Fail ( t , fmt . Sprintf ( "\"%s\" does not contain \"%s\"" , list , element ) , msgAndArgs ... )
}
}
return true
}
// NotSubset asserts that the specified list(array, slice...) contains not all
// elements given in the specified subset(array, slice...).
//
// assert.NotSubset(t, [1, 3, 4], [1, 2], "But [1, 3, 4] does not contain [1, 2]")
func NotSubset ( t TestingT , list , subset interface { } , msgAndArgs ... interface { } ) ( ok bool ) {
if subset == nil {
return Fail ( t , fmt . Sprintf ( "nil is the empty set which is a subset of every set" ) , msgAndArgs ... )
}
subsetValue := reflect . ValueOf ( subset )
defer func ( ) {
if e := recover ( ) ; e != nil {
ok = false
}
} ( )
listKind := reflect . TypeOf ( list ) . Kind ( )
subsetKind := reflect . TypeOf ( subset ) . Kind ( )
if listKind != reflect . Array && listKind != reflect . Slice {
return Fail ( t , fmt . Sprintf ( "%q has an unsupported type %s" , list , listKind ) , msgAndArgs ... )
}
if subsetKind != reflect . Array && subsetKind != reflect . Slice {
return Fail ( t , fmt . Sprintf ( "%q has an unsupported type %s" , subset , subsetKind ) , msgAndArgs ... )
}
for i := 0 ; i < subsetValue . Len ( ) ; i ++ {
element := subsetValue . Index ( i ) . Interface ( )
ok , found := includeElement ( list , element )
if ! ok {
return Fail ( t , fmt . Sprintf ( "\"%s\" could not be applied builtin len()" , list ) , msgAndArgs ... )
}
if ! found {
return true
}
}
return Fail ( t , fmt . Sprintf ( "%q is a subset of %q" , subset , list ) , msgAndArgs ... )
}
// ElementsMatch asserts that the specified listA(array, slice...) is equal to specified
// listB(array, slice...) ignoring the order of the elements. If there are duplicate elements,
// the number of appearances of each of them in both lists should match.
//
// assert.ElementsMatch(t, [1, 3, 2, 3], [1, 3, 3, 2])
func ElementsMatch ( t TestingT , listA , listB interface { } , msgAndArgs ... interface { } ) ( ok bool ) {
if isEmpty ( listA ) && isEmpty ( listB ) {
return true
}
aKind := reflect . TypeOf ( listA ) . Kind ( )
bKind := reflect . TypeOf ( listB ) . Kind ( )
if aKind != reflect . Array && aKind != reflect . Slice {
return Fail ( t , fmt . Sprintf ( "%q has an unsupported type %s" , listA , aKind ) , msgAndArgs ... )
}
if bKind != reflect . Array && bKind != reflect . Slice {
return Fail ( t , fmt . Sprintf ( "%q has an unsupported type %s" , listB , bKind ) , msgAndArgs ... )
}
aValue := reflect . ValueOf ( listA )
bValue := reflect . ValueOf ( listB )
aLen := aValue . Len ( )
bLen := bValue . Len ( )
if aLen != bLen {
return Fail ( t , fmt . Sprintf ( "lengths don't match: %d != %d" , aLen , bLen ) , msgAndArgs ... )
}
// Mark indexes in bValue that we already used
visited := make ( [ ] bool , bLen )
for i := 0 ; i < aLen ; i ++ {
element := aValue . Index ( i ) . Interface ( )
found := false
for j := 0 ; j < bLen ; j ++ {
if visited [ j ] {
continue
}
if ObjectsAreEqual ( bValue . Index ( j ) . Interface ( ) , element ) {
visited [ j ] = true
found = true
break
}
}
if ! found {
return Fail ( t , fmt . Sprintf ( "element %s appears more times in %s than in %s" , element , aValue , bValue ) , msgAndArgs ... )
}
}
return true
}
// Condition uses a Comparison to assert a complex condition.
func Condition ( t TestingT , comp Comparison , msgAndArgs ... interface { } ) bool {
result := comp ( )
if ! result {
Fail ( t , "Condition failed!" , msgAndArgs ... )
}
return result
}
// PanicTestFunc defines a func that should be passed to the assert.Panics and assert.NotPanics
// methods, and represents a simple func that takes no arguments, and returns nothing.
type PanicTestFunc func ( )
// didPanic returns true if the function passed to it panics. Otherwise, it returns false.
func didPanic ( f PanicTestFunc ) ( bool , interface { } ) {
didPanic := false
var message interface { }
func ( ) {
defer func ( ) {
if message = recover ( ) ; message != nil {
didPanic = true
}
} ( )
// call the target function
f ( )
} ( )
return didPanic , message
}
// Panics asserts that the code inside the specified PanicTestFunc panics.
//
// assert.Panics(t, func(){ GoCrazy() })
func Panics ( t TestingT , f PanicTestFunc , msgAndArgs ... interface { } ) bool {
if funcDidPanic , panicValue := didPanic ( f ) ; ! funcDidPanic {
return Fail ( t , fmt . Sprintf ( "func %#v should panic\n\r\tPanic value:\t%v" , f , panicValue ) , msgAndArgs ... )
}
return true
}
// PanicsWithValue asserts that the code inside the specified PanicTestFunc panics, and that
// the recovered panic value equals the expected panic value.
//
// assert.PanicsWithValue(t, "crazy error", func(){ GoCrazy() })
func PanicsWithValue ( t TestingT , expected interface { } , f PanicTestFunc , msgAndArgs ... interface { } ) bool {
funcDidPanic , panicValue := didPanic ( f )
if ! funcDidPanic {
return Fail ( t , fmt . Sprintf ( "func %#v should panic\n\r\tPanic value:\t%v" , f , panicValue ) , msgAndArgs ... )
}
if panicValue != expected {
return Fail ( t , fmt . Sprintf ( "func %#v should panic with value:\t%v\n\r\tPanic value:\t%v" , f , expected , panicValue ) , msgAndArgs ... )
}
return true
}
// NotPanics asserts that the code inside the specified PanicTestFunc does NOT panic.
//
// assert.NotPanics(t, func(){ RemainCalm() })
func NotPanics ( t TestingT , f PanicTestFunc , msgAndArgs ... interface { } ) bool {
if funcDidPanic , panicValue := didPanic ( f ) ; funcDidPanic {
return Fail ( t , fmt . Sprintf ( "func %#v should not panic\n\r\tPanic value:\t%v" , f , panicValue ) , msgAndArgs ... )
}
return true
}
// WithinDuration asserts that the two times are within duration delta of each other.
//
// assert.WithinDuration(t, time.Now(), time.Now(), 10*time.Second)
func WithinDuration ( t TestingT , expected , actual time . Time , delta time . Duration , msgAndArgs ... interface { } ) bool {
dt := expected . Sub ( actual )
if dt < - delta || dt > delta {
return Fail ( t , fmt . Sprintf ( "Max difference between %v and %v allowed is %v, but difference was %v" , expected , actual , delta , dt ) , msgAndArgs ... )
}
return true
}
func toFloat ( x interface { } ) ( float64 , bool ) {
var xf float64
xok := true
switch xn := x . ( type ) {
case uint8 :
xf = float64 ( xn )
case uint16 :
xf = float64 ( xn )
case uint32 :
xf = float64 ( xn )
case uint64 :
xf = float64 ( xn )
case int :
xf = float64 ( xn )
case int8 :
xf = float64 ( xn )
case int16 :
xf = float64 ( xn )
case int32 :
xf = float64 ( xn )
case int64 :
xf = float64 ( xn )
case float32 :
xf = float64 ( xn )
case float64 :
xf = float64 ( xn )
case time . Duration :
xf = float64 ( xn )
default :
xok = false
}
return xf , xok
}
// InDelta asserts that the two numerals are within delta of each other.
//
// assert.InDelta(t, math.Pi, (22 / 7.0), 0.01)
func InDelta ( t TestingT , expected , actual interface { } , delta float64 , msgAndArgs ... interface { } ) bool {
af , aok := toFloat ( expected )
bf , bok := toFloat ( actual )
if ! aok || ! bok {
return Fail ( t , fmt . Sprintf ( "Parameters must be numerical" ) , msgAndArgs ... )
}
if math . IsNaN ( af ) {
return Fail ( t , fmt . Sprintf ( "Expected must not be NaN" ) , msgAndArgs ... )
}
if math . IsNaN ( bf ) {
return Fail ( t , fmt . Sprintf ( "Expected %v with delta %v, but was NaN" , expected , delta ) , msgAndArgs ... )
}
dt := af - bf
if dt < - delta || dt > delta {
return Fail ( t , fmt . Sprintf ( "Max difference between %v and %v allowed is %v, but difference was %v" , expected , actual , delta , dt ) , msgAndArgs ... )
}
return true
}
// InDeltaSlice is the same as InDelta, except it compares two slices.
func InDeltaSlice ( t TestingT , expected , actual interface { } , delta float64 , msgAndArgs ... interface { } ) bool {
if expected == nil || actual == nil ||
reflect . TypeOf ( actual ) . Kind ( ) != reflect . Slice ||
reflect . TypeOf ( expected ) . Kind ( ) != reflect . Slice {
return Fail ( t , fmt . Sprintf ( "Parameters must be slice" ) , msgAndArgs ... )
}
actualSlice := reflect . ValueOf ( actual )
expectedSlice := reflect . ValueOf ( expected )
for i := 0 ; i < actualSlice . Len ( ) ; i ++ {
result := InDelta ( t , actualSlice . Index ( i ) . Interface ( ) , expectedSlice . Index ( i ) . Interface ( ) , delta , msgAndArgs ... )
if ! result {
return result
}
}
return true
}
// InDeltaMapValues is the same as InDelta, but it compares all values between two maps. Both maps must have exactly the same keys.
func InDeltaMapValues ( t TestingT , expected , actual interface { } , delta float64 , msgAndArgs ... interface { } ) bool {
if expected == nil || actual == nil ||
reflect . TypeOf ( actual ) . Kind ( ) != reflect . Map ||
reflect . TypeOf ( expected ) . Kind ( ) != reflect . Map {
return Fail ( t , "Arguments must be maps" , msgAndArgs ... )
}
expectedMap := reflect . ValueOf ( expected )
actualMap := reflect . ValueOf ( actual )
if expectedMap . Len ( ) != actualMap . Len ( ) {
return Fail ( t , "Arguments must have the same number of keys" , msgAndArgs ... )
}
for _ , k := range expectedMap . MapKeys ( ) {
ev := expectedMap . MapIndex ( k )
av := actualMap . MapIndex ( k )
if ! ev . IsValid ( ) {
return Fail ( t , fmt . Sprintf ( "missing key %q in expected map" , k ) , msgAndArgs ... )
}
if ! av . IsValid ( ) {
return Fail ( t , fmt . Sprintf ( "missing key %q in actual map" , k ) , msgAndArgs ... )
}
if ! InDelta (
t ,
ev . Interface ( ) ,
av . Interface ( ) ,
delta ,
msgAndArgs ... ,
) {
return false
}
}
return true
}
func calcRelativeError ( expected , actual interface { } ) ( float64 , error ) {
af , aok := toFloat ( expected )
if ! aok {
return 0 , fmt . Errorf ( "expected value %q cannot be converted to float" , expected )
}
if af == 0 {
return 0 , fmt . Errorf ( "expected value must have a value other than zero to calculate the relative error" )
}
bf , bok := toFloat ( actual )
if ! bok {
return 0 , fmt . Errorf ( "actual value %q cannot be converted to float" , actual )
}
return math . Abs ( af - bf ) / math . Abs ( af ) , nil
}
// InEpsilon asserts that expected and actual have a relative error less than epsilon
func InEpsilon ( t TestingT , expected , actual interface { } , epsilon float64 , msgAndArgs ... interface { } ) bool {
actualEpsilon , err := calcRelativeError ( expected , actual )
if err != nil {
return Fail ( t , err . Error ( ) , msgAndArgs ... )
}
if actualEpsilon > epsilon {
return Fail ( t , fmt . Sprintf ( "Relative error is too high: %#v (expected)\n" +
" < %#v (actual)" , epsilon , actualEpsilon ) , msgAndArgs ... )
}
return true
}
// InEpsilonSlice is the same as InEpsilon, except it compares each value from two slices.
func InEpsilonSlice ( t TestingT , expected , actual interface { } , epsilon float64 , msgAndArgs ... interface { } ) bool {
if expected == nil || actual == nil ||
reflect . TypeOf ( actual ) . Kind ( ) != reflect . Slice ||
reflect . TypeOf ( expected ) . Kind ( ) != reflect . Slice {
return Fail ( t , fmt . Sprintf ( "Parameters must be slice" ) , msgAndArgs ... )
}
actualSlice := reflect . ValueOf ( actual )
expectedSlice := reflect . ValueOf ( expected )
for i := 0 ; i < actualSlice . Len ( ) ; i ++ {
result := InEpsilon ( t , actualSlice . Index ( i ) . Interface ( ) , expectedSlice . Index ( i ) . Interface ( ) , epsilon )
if ! result {
return result
}
}
return true
}
/ *
Errors
* /
// NoError asserts that a function returned no error (i.e. `nil`).
//
// actualObj, err := SomeFunction()
// if assert.NoError(t, err) {
// assert.Equal(t, expectedObj, actualObj)
// }
func NoError ( t TestingT , err error , msgAndArgs ... interface { } ) bool {
if err != nil {
return Fail ( t , fmt . Sprintf ( "Received unexpected error:\n%+v" , err ) , msgAndArgs ... )
}
return true
}
// Error asserts that a function returned an error (i.e. not `nil`).
//
// actualObj, err := SomeFunction()
// if assert.Error(t, err) {
// assert.Equal(t, expectedError, err)
// }
func Error ( t TestingT , err error , msgAndArgs ... interface { } ) bool {
if err == nil {
return Fail ( t , "An error is expected but got nil." , msgAndArgs ... )
}
return true
}
// EqualError asserts that a function returned an error (i.e. not `nil`)
// and that it is equal to the provided error.
//
// actualObj, err := SomeFunction()
// assert.EqualError(t, err, expectedErrorString)
func EqualError ( t TestingT , theError error , errString string , msgAndArgs ... interface { } ) bool {
if ! Error ( t , theError , msgAndArgs ... ) {
return false
}
expected := errString
actual := theError . Error ( )
// don't need to use deep equals here, we know they are both strings
if expected != actual {
return Fail ( t , fmt . Sprintf ( "Error message not equal:\n" +
"expected: %q\n" +
"actual : %q" , expected , actual ) , msgAndArgs ... )
}
return true
}
// matchRegexp return true if a specified regexp matches a string.
func matchRegexp ( rx interface { } , str interface { } ) bool {
var r * regexp . Regexp
if rr , ok := rx . ( * regexp . Regexp ) ; ok {
r = rr
} else {
r = regexp . MustCompile ( fmt . Sprint ( rx ) )
}
return ( r . FindStringIndex ( fmt . Sprint ( str ) ) != nil )
}
// Regexp asserts that a specified regexp matches a string.
//
// assert.Regexp(t, regexp.MustCompile("start"), "it's starting")
// assert.Regexp(t, "start...$", "it's not starting")
func Regexp ( t TestingT , rx interface { } , str interface { } , msgAndArgs ... interface { } ) bool {
match := matchRegexp ( rx , str )
if ! match {
Fail ( t , fmt . Sprintf ( "Expect \"%v\" to match \"%v\"" , str , rx ) , msgAndArgs ... )
}
return match
}
// NotRegexp asserts that a specified regexp does not match a string.
//
// assert.NotRegexp(t, regexp.MustCompile("starts"), "it's starting")
// assert.NotRegexp(t, "^start", "it's not starting")
func NotRegexp ( t TestingT , rx interface { } , str interface { } , msgAndArgs ... interface { } ) bool {
match := matchRegexp ( rx , str )
if match {
Fail ( t , fmt . Sprintf ( "Expect \"%v\" to NOT match \"%v\"" , str , rx ) , msgAndArgs ... )
}
return ! match
}
// Zero asserts that i is the zero value for its type.
func Zero ( t TestingT , i interface { } , msgAndArgs ... interface { } ) bool {
if i != nil && ! reflect . DeepEqual ( i , reflect . Zero ( reflect . TypeOf ( i ) ) . Interface ( ) ) {
return Fail ( t , fmt . Sprintf ( "Should be zero, but was %v" , i ) , msgAndArgs ... )
}
return true
}
// NotZero asserts that i is not the zero value for its type.
func NotZero ( t TestingT , i interface { } , msgAndArgs ... interface { } ) bool {
if i == nil || reflect . DeepEqual ( i , reflect . Zero ( reflect . TypeOf ( i ) ) . Interface ( ) ) {
return Fail ( t , fmt . Sprintf ( "Should not be zero, but was %v" , i ) , msgAndArgs ... )
}
return true
}
// FileExists checks whether a file exists in the given path. It also fails if the path points to a directory or there is an error when trying to check the file.
func FileExists ( t TestingT , path string , msgAndArgs ... interface { } ) bool {
info , err := os . Lstat ( path )
if err != nil {
if os . IsNotExist ( err ) {
return Fail ( t , fmt . Sprintf ( "unable to find file %q" , path ) , msgAndArgs ... )
}
return Fail ( t , fmt . Sprintf ( "error when running os.Lstat(%q): %s" , path , err ) , msgAndArgs ... )
}
if info . IsDir ( ) {
return Fail ( t , fmt . Sprintf ( "%q is a directory" , path ) , msgAndArgs ... )
}
return true
}
// DirExists checks whether a directory exists in the given path. It also fails if the path is a file rather a directory or there is an error checking whether it exists.
func DirExists ( t TestingT , path string , msgAndArgs ... interface { } ) bool {
info , err := os . Lstat ( path )
if err != nil {
if os . IsNotExist ( err ) {
return Fail ( t , fmt . Sprintf ( "unable to find file %q" , path ) , msgAndArgs ... )
}
return Fail ( t , fmt . Sprintf ( "error when running os.Lstat(%q): %s" , path , err ) , msgAndArgs ... )
}
if ! info . IsDir ( ) {
return Fail ( t , fmt . Sprintf ( "%q is a file" , path ) , msgAndArgs ... )
}
return true
}
// JSONEq asserts that two JSON strings are equivalent.
//
// assert.JSONEq(t, `{"hello": "world", "foo": "bar"}`, `{"foo": "bar", "hello": "world"}`)
func JSONEq ( t TestingT , expected string , actual string , msgAndArgs ... interface { } ) bool {
var expectedJSONAsInterface , actualJSONAsInterface interface { }
if err := json . Unmarshal ( [ ] byte ( expected ) , & expectedJSONAsInterface ) ; err != nil {
return Fail ( t , fmt . Sprintf ( "Expected value ('%s') is not valid json.\nJSON parsing error: '%s'" , expected , err . Error ( ) ) , msgAndArgs ... )
}
if err := json . Unmarshal ( [ ] byte ( actual ) , & actualJSONAsInterface ) ; err != nil {
return Fail ( t , fmt . Sprintf ( "Input ('%s') needs to be valid json.\nJSON parsing error: '%s'" , actual , err . Error ( ) ) , msgAndArgs ... )
}
return Equal ( t , expectedJSONAsInterface , actualJSONAsInterface , msgAndArgs ... )
}
func typeAndKind ( v interface { } ) ( reflect . Type , reflect . Kind ) {
t := reflect . TypeOf ( v )
k := t . Kind ( )
if k == reflect . Ptr {
t = t . Elem ( )
k = t . Kind ( )
}
return t , k
}
// diff returns a diff of both values as long as both are of the same type and
// are a struct, map, slice or array. Otherwise it returns an empty string.
func diff ( expected interface { } , actual interface { } ) string {
if expected == nil || actual == nil {
return ""
}
et , ek := typeAndKind ( expected )
at , _ := typeAndKind ( actual )
if et != at {
return ""
}
if ek != reflect . Struct && ek != reflect . Map && ek != reflect . Slice && ek != reflect . Array {
return ""
}
e := spewConfig . Sdump ( expected )
a := spewConfig . Sdump ( actual )
diff , _ := difflib . GetUnifiedDiffString ( difflib . UnifiedDiff {
A : difflib . SplitLines ( e ) ,
B : difflib . SplitLines ( a ) ,
FromFile : "Expected" ,
FromDate : "" ,
ToFile : "Actual" ,
ToDate : "" ,
Context : 1 ,
} )
return "\n\nDiff:\n" + diff
}
// validateEqualArgs checks whether provided arguments can be safely used in the
// Equal/NotEqual functions.
func validateEqualArgs ( expected , actual interface { } ) error {
if isFunction ( expected ) || isFunction ( actual ) {
return errors . New ( "cannot take func type as argument" )
}
return nil
}
func isFunction ( arg interface { } ) bool {
if arg == nil {
return false
}
return reflect . TypeOf ( arg ) . Kind ( ) == reflect . Func
}
var spewConfig = spew . ConfigState {
Indent : " " ,
DisablePointerAddresses : true ,
DisableCapacities : true ,
SortKeys : true ,
}