diff --git a/vendor/github.com/stretchr/testify/assert/assertion_format.go b/vendor/github.com/stretchr/testify/assert/assertion_format.go
index e0364e9..bf89ecd 100644
--- a/vendor/github.com/stretchr/testify/assert/assertion_format.go
+++ b/vendor/github.com/stretchr/testify/assert/assertion_format.go
@@ -32,7 +32,8 @@
 	return Contains(t, s, contains, append([]interface{}{msg}, args...)...)
 }
 
-// DirExistsf 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.
+// DirExistsf 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 DirExistsf(t TestingT, path string, msg string, args ...interface{}) bool {
 	if h, ok := t.(tHelper); ok {
 		h.Helper()
@@ -160,7 +161,8 @@
 	return False(t, value, append([]interface{}{msg}, args...)...)
 }
 
-// FileExistsf 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.
+// FileExistsf 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 FileExistsf(t TestingT, path string, msg string, args ...interface{}) bool {
 	if h, ok := t.(tHelper); ok {
 		h.Helper()
@@ -267,7 +269,7 @@
 
 // InDeltaf asserts that the two numerals are within delta of each other.
 //
-// 	 assert.InDeltaf(t, math.Pi, (22 / 7.0, "error message %s", "formatted"), 0.01)
+// 	 assert.InDeltaf(t, math.Pi, 22/7.0, 0.01, "error message %s", "formatted")
 func InDeltaf(t TestingT, expected interface{}, actual interface{}, delta float64, msg string, args ...interface{}) bool {
 	if h, ok := t.(tHelper); ok {
 		h.Helper()
@@ -325,14 +327,6 @@
 	return JSONEq(t, expected, actual, append([]interface{}{msg}, args...)...)
 }
 
-// YAMLEqf asserts that two YAML strings are equivalent.
-func YAMLEqf(t TestingT, expected string, actual string, msg string, args ...interface{}) bool {
-	if h, ok := t.(tHelper); ok {
-		h.Helper()
-	}
-	return YAMLEq(t, expected, actual, append([]interface{}{msg}, args...)...)
-}
-
 // Lenf asserts that the specified object has specific length.
 // Lenf also fails if the object has a type that len() not accept.
 //
@@ -369,6 +363,17 @@
 	return LessOrEqual(t, e1, e2, append([]interface{}{msg}, args...)...)
 }
 
+// Neverf asserts that the given condition doesn't satisfy in waitFor time,
+// periodically checking the target function each tick.
+//
+//    assert.Neverf(t, func() bool { return false; }, time.Second, 10*time.Millisecond, "error message %s", "formatted")
+func Neverf(t TestingT, condition func() bool, waitFor time.Duration, tick time.Duration, msg string, args ...interface{}) bool {
+	if h, ok := t.(tHelper); ok {
+		h.Helper()
+	}
+	return Never(t, condition, waitFor, tick, append([]interface{}{msg}, args...)...)
+}
+
 // Nilf asserts that the specified object is nil.
 //
 //    assert.Nilf(t, err, "error message %s", "formatted")
@@ -379,6 +384,15 @@
 	return Nil(t, object, append([]interface{}{msg}, args...)...)
 }
 
+// NoDirExistsf checks whether a directory does not exist in the given path.
+// It fails if the path points to an existing _directory_ only.
+func NoDirExistsf(t TestingT, path string, msg string, args ...interface{}) bool {
+	if h, ok := t.(tHelper); ok {
+		h.Helper()
+	}
+	return NoDirExists(t, path, append([]interface{}{msg}, args...)...)
+}
+
 // NoErrorf asserts that a function returned no error (i.e. `nil`).
 //
 //   actualObj, err := SomeFunction()
@@ -392,6 +406,15 @@
 	return NoError(t, err, append([]interface{}{msg}, args...)...)
 }
 
+// NoFileExistsf checks whether a file does not exist in a given path. It fails
+// if the path points to an existing _file_ only.
+func NoFileExistsf(t TestingT, path string, msg string, args ...interface{}) bool {
+	if h, ok := t.(tHelper); ok {
+		h.Helper()
+	}
+	return NoFileExists(t, path, append([]interface{}{msg}, args...)...)
+}
+
 // NotContainsf asserts that the specified string, list(array, slice...) or map does NOT contain the
 // specified substring or element.
 //
@@ -462,6 +485,19 @@
 	return NotRegexp(t, rx, str, append([]interface{}{msg}, args...)...)
 }
 
+// NotSamef asserts that two pointers do not reference the same object.
+//
+//    assert.NotSamef(t, ptr1, ptr2, "error message %s", "formatted")
+//
+// Both arguments must be pointer variables. Pointer variable sameness is
+// determined based on the equality of both type and value.
+func NotSamef(t TestingT, expected interface{}, actual interface{}, msg string, args ...interface{}) bool {
+	if h, ok := t.(tHelper); ok {
+		h.Helper()
+	}
+	return NotSame(t, expected, actual, append([]interface{}{msg}, args...)...)
+}
+
 // NotSubsetf asserts that the specified list(array, slice...) contains not all
 // elements given in the specified subset(array, slice...).
 //
@@ -491,6 +527,18 @@
 	return Panics(t, f, append([]interface{}{msg}, args...)...)
 }
 
+// PanicsWithErrorf asserts that the code inside the specified PanicTestFunc
+// panics, and that the recovered panic value is an error that satisfies the
+// EqualError comparison.
+//
+//   assert.PanicsWithErrorf(t, "crazy error", func(){ GoCrazy() }, "error message %s", "formatted")
+func PanicsWithErrorf(t TestingT, errString string, f PanicTestFunc, msg string, args ...interface{}) bool {
+	if h, ok := t.(tHelper); ok {
+		h.Helper()
+	}
+	return PanicsWithError(t, errString, f, append([]interface{}{msg}, args...)...)
+}
+
 // PanicsWithValuef asserts that the code inside the specified PanicTestFunc panics, and that
 // the recovered panic value equals the expected panic value.
 //
@@ -557,6 +605,14 @@
 	return WithinDuration(t, expected, actual, delta, append([]interface{}{msg}, args...)...)
 }
 
+// YAMLEqf asserts that two YAML strings are equivalent.
+func YAMLEqf(t TestingT, expected string, actual string, msg string, args ...interface{}) bool {
+	if h, ok := t.(tHelper); ok {
+		h.Helper()
+	}
+	return YAMLEq(t, expected, actual, append([]interface{}{msg}, args...)...)
+}
+
 // Zerof asserts that i is the zero value for its type.
 func Zerof(t TestingT, i interface{}, msg string, args ...interface{}) bool {
 	if h, ok := t.(tHelper); ok {
diff --git a/vendor/github.com/stretchr/testify/assert/assertion_forward.go b/vendor/github.com/stretchr/testify/assert/assertion_forward.go
index 2683040..75ecdca 100644
--- a/vendor/github.com/stretchr/testify/assert/assertion_forward.go
+++ b/vendor/github.com/stretchr/testify/assert/assertion_forward.go
@@ -53,7 +53,8 @@
 	return Containsf(a.t, s, contains, msg, args...)
 }
 
-// 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.
+// 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 (a *Assertions) DirExists(path string, msgAndArgs ...interface{}) bool {
 	if h, ok := a.t.(tHelper); ok {
 		h.Helper()
@@ -61,7 +62,8 @@
 	return DirExists(a.t, path, msgAndArgs...)
 }
 
-// DirExistsf 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.
+// DirExistsf 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 (a *Assertions) DirExistsf(path string, msg string, args ...interface{}) bool {
 	if h, ok := a.t.(tHelper); ok {
 		h.Helper()
@@ -309,7 +311,8 @@
 	return Falsef(a.t, value, msg, args...)
 }
 
-// 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.
+// 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 (a *Assertions) FileExists(path string, msgAndArgs ...interface{}) bool {
 	if h, ok := a.t.(tHelper); ok {
 		h.Helper()
@@ -317,7 +320,8 @@
 	return FileExists(a.t, path, msgAndArgs...)
 }
 
-// FileExistsf 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.
+// FileExistsf 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 (a *Assertions) FileExistsf(path string, msg string, args ...interface{}) bool {
 	if h, ok := a.t.(tHelper); ok {
 		h.Helper()
@@ -521,7 +525,7 @@
 
 // InDelta asserts that the two numerals are within delta of each other.
 //
-// 	 a.InDelta(math.Pi, (22 / 7.0), 0.01)
+// 	 a.InDelta(math.Pi, 22/7.0, 0.01)
 func (a *Assertions) InDelta(expected interface{}, actual interface{}, delta float64, msgAndArgs ...interface{}) bool {
 	if h, ok := a.t.(tHelper); ok {
 		h.Helper()
@@ -563,7 +567,7 @@
 
 // InDeltaf asserts that the two numerals are within delta of each other.
 //
-// 	 a.InDeltaf(math.Pi, (22 / 7.0, "error message %s", "formatted"), 0.01)
+// 	 a.InDeltaf(math.Pi, 22/7.0, 0.01, "error message %s", "formatted")
 func (a *Assertions) InDeltaf(expected interface{}, actual interface{}, delta float64, msg string, args ...interface{}) bool {
 	if h, ok := a.t.(tHelper); ok {
 		h.Helper()
@@ -639,22 +643,6 @@
 	return JSONEqf(a.t, expected, actual, msg, args...)
 }
 
-// YAMLEq asserts that two YAML strings are equivalent.
-func (a *Assertions) YAMLEq(expected string, actual string, msgAndArgs ...interface{}) bool {
-	if h, ok := a.t.(tHelper); ok {
-		h.Helper()
-	}
-	return YAMLEq(a.t, expected, actual, msgAndArgs...)
-}
-
-// YAMLEqf asserts that two YAML strings are equivalent.
-func (a *Assertions) YAMLEqf(expected string, actual string, msg string, args ...interface{}) bool {
-	if h, ok := a.t.(tHelper); ok {
-		h.Helper()
-	}
-	return YAMLEqf(a.t, expected, actual, msg, args...)
-}
-
 // Len asserts that the specified object has specific length.
 // Len also fails if the object has a type that len() not accept.
 //
@@ -727,6 +715,28 @@
 	return Lessf(a.t, e1, e2, msg, args...)
 }
 
+// Never asserts that the given condition doesn't satisfy in waitFor time,
+// periodically checking the target function each tick.
+//
+//    a.Never(func() bool { return false; }, time.Second, 10*time.Millisecond)
+func (a *Assertions) Never(condition func() bool, waitFor time.Duration, tick time.Duration, msgAndArgs ...interface{}) bool {
+	if h, ok := a.t.(tHelper); ok {
+		h.Helper()
+	}
+	return Never(a.t, condition, waitFor, tick, msgAndArgs...)
+}
+
+// Neverf asserts that the given condition doesn't satisfy in waitFor time,
+// periodically checking the target function each tick.
+//
+//    a.Neverf(func() bool { return false; }, time.Second, 10*time.Millisecond, "error message %s", "formatted")
+func (a *Assertions) Neverf(condition func() bool, waitFor time.Duration, tick time.Duration, msg string, args ...interface{}) bool {
+	if h, ok := a.t.(tHelper); ok {
+		h.Helper()
+	}
+	return Neverf(a.t, condition, waitFor, tick, msg, args...)
+}
+
 // Nil asserts that the specified object is nil.
 //
 //    a.Nil(err)
@@ -747,6 +757,24 @@
 	return Nilf(a.t, object, msg, args...)
 }
 
+// NoDirExists checks whether a directory does not exist in the given path.
+// It fails if the path points to an existing _directory_ only.
+func (a *Assertions) NoDirExists(path string, msgAndArgs ...interface{}) bool {
+	if h, ok := a.t.(tHelper); ok {
+		h.Helper()
+	}
+	return NoDirExists(a.t, path, msgAndArgs...)
+}
+
+// NoDirExistsf checks whether a directory does not exist in the given path.
+// It fails if the path points to an existing _directory_ only.
+func (a *Assertions) NoDirExistsf(path string, msg string, args ...interface{}) bool {
+	if h, ok := a.t.(tHelper); ok {
+		h.Helper()
+	}
+	return NoDirExistsf(a.t, path, msg, args...)
+}
+
 // NoError asserts that a function returned no error (i.e. `nil`).
 //
 //   actualObj, err := SomeFunction()
@@ -773,6 +801,24 @@
 	return NoErrorf(a.t, err, msg, args...)
 }
 
+// NoFileExists checks whether a file does not exist in a given path. It fails
+// if the path points to an existing _file_ only.
+func (a *Assertions) NoFileExists(path string, msgAndArgs ...interface{}) bool {
+	if h, ok := a.t.(tHelper); ok {
+		h.Helper()
+	}
+	return NoFileExists(a.t, path, msgAndArgs...)
+}
+
+// NoFileExistsf checks whether a file does not exist in a given path. It fails
+// if the path points to an existing _file_ only.
+func (a *Assertions) NoFileExistsf(path string, msg string, args ...interface{}) bool {
+	if h, ok := a.t.(tHelper); ok {
+		h.Helper()
+	}
+	return NoFileExistsf(a.t, path, msg, args...)
+}
+
 // NotContains asserts that the specified string, list(array, slice...) or map does NOT contain the
 // specified substring or element.
 //
@@ -913,6 +959,32 @@
 	return NotRegexpf(a.t, rx, str, msg, args...)
 }
 
+// NotSame asserts that two pointers do not reference the same object.
+//
+//    a.NotSame(ptr1, ptr2)
+//
+// Both arguments must be pointer variables. Pointer variable sameness is
+// determined based on the equality of both type and value.
+func (a *Assertions) NotSame(expected interface{}, actual interface{}, msgAndArgs ...interface{}) bool {
+	if h, ok := a.t.(tHelper); ok {
+		h.Helper()
+	}
+	return NotSame(a.t, expected, actual, msgAndArgs...)
+}
+
+// NotSamef asserts that two pointers do not reference the same object.
+//
+//    a.NotSamef(ptr1, ptr2, "error message %s", "formatted")
+//
+// Both arguments must be pointer variables. Pointer variable sameness is
+// determined based on the equality of both type and value.
+func (a *Assertions) NotSamef(expected interface{}, actual interface{}, msg string, args ...interface{}) bool {
+	if h, ok := a.t.(tHelper); ok {
+		h.Helper()
+	}
+	return NotSamef(a.t, expected, actual, msg, args...)
+}
+
 // NotSubset asserts that the specified list(array, slice...) contains not all
 // elements given in the specified subset(array, slice...).
 //
@@ -961,6 +1033,30 @@
 	return Panics(a.t, f, msgAndArgs...)
 }
 
+// PanicsWithError asserts that the code inside the specified PanicTestFunc
+// panics, and that the recovered panic value is an error that satisfies the
+// EqualError comparison.
+//
+//   a.PanicsWithError("crazy error", func(){ GoCrazy() })
+func (a *Assertions) PanicsWithError(errString string, f PanicTestFunc, msgAndArgs ...interface{}) bool {
+	if h, ok := a.t.(tHelper); ok {
+		h.Helper()
+	}
+	return PanicsWithError(a.t, errString, f, msgAndArgs...)
+}
+
+// PanicsWithErrorf asserts that the code inside the specified PanicTestFunc
+// panics, and that the recovered panic value is an error that satisfies the
+// EqualError comparison.
+//
+//   a.PanicsWithErrorf("crazy error", func(){ GoCrazy() }, "error message %s", "formatted")
+func (a *Assertions) PanicsWithErrorf(errString string, f PanicTestFunc, msg string, args ...interface{}) bool {
+	if h, ok := a.t.(tHelper); ok {
+		h.Helper()
+	}
+	return PanicsWithErrorf(a.t, errString, f, msg, args...)
+}
+
 // PanicsWithValue asserts that the code inside the specified PanicTestFunc panics, and that
 // the recovered panic value equals the expected panic value.
 //
@@ -1103,6 +1199,22 @@
 	return WithinDurationf(a.t, expected, actual, delta, msg, args...)
 }
 
+// YAMLEq asserts that two YAML strings are equivalent.
+func (a *Assertions) YAMLEq(expected string, actual string, msgAndArgs ...interface{}) bool {
+	if h, ok := a.t.(tHelper); ok {
+		h.Helper()
+	}
+	return YAMLEq(a.t, expected, actual, msgAndArgs...)
+}
+
+// YAMLEqf asserts that two YAML strings are equivalent.
+func (a *Assertions) YAMLEqf(expected string, actual string, msg string, args ...interface{}) bool {
+	if h, ok := a.t.(tHelper); ok {
+		h.Helper()
+	}
+	return YAMLEqf(a.t, expected, actual, msg, args...)
+}
+
 // Zero asserts that i is the zero value for its type.
 func (a *Assertions) Zero(i interface{}, msgAndArgs ...interface{}) bool {
 	if h, ok := a.t.(tHelper); ok {
diff --git a/vendor/github.com/stretchr/testify/assert/assertions.go b/vendor/github.com/stretchr/testify/assert/assertions.go
index 044da8b..bdd8138 100644
--- a/vendor/github.com/stretchr/testify/assert/assertions.go
+++ b/vendor/github.com/stretchr/testify/assert/assertions.go
@@ -11,6 +11,7 @@
 	"reflect"
 	"regexp"
 	"runtime"
+	"runtime/debug"
 	"strings"
 	"time"
 	"unicode"
@@ -21,7 +22,7 @@
 	yaml "gopkg.in/yaml.v2"
 )
 
-//go:generate go run ../_codegen/main.go -output-package=assert -template=assertion_format.go.tmpl
+//go:generate sh -c "cd ../_codegen && go build && cd - && ../_codegen/_codegen -output-package=assert -template=assertion_format.go.tmpl"
 
 // TestingT is an interface wrapper around *testing.T
 type TestingT interface {
@@ -351,6 +352,19 @@
 
 }
 
+// validateEqualArgs checks whether provided arguments can be safely used in the
+// Equal/NotEqual functions.
+func validateEqualArgs(expected, actual interface{}) error {
+	if expected == nil && actual == nil {
+		return nil
+	}
+
+	if isFunction(expected) || isFunction(actual) {
+		return errors.New("cannot take func type as argument")
+	}
+	return nil
+}
+
 // Same asserts that two pointers reference the same object.
 //
 //    assert.Same(t, ptr1, ptr2)
@@ -362,18 +376,7 @@
 		h.Helper()
 	}
 
-	expectedPtr, actualPtr := reflect.ValueOf(expected), reflect.ValueOf(actual)
-	if expectedPtr.Kind() != reflect.Ptr || actualPtr.Kind() != reflect.Ptr {
-		return Fail(t, "Invalid operation: both arguments must be pointers", msgAndArgs...)
-	}
-
-	expectedType, actualType := reflect.TypeOf(expected), reflect.TypeOf(actual)
-	if expectedType != actualType {
-		return Fail(t, fmt.Sprintf("Pointer expected to be of type %v, but was %v",
-			expectedType, actualType), msgAndArgs...)
-	}
-
-	if expected != actual {
+	if !samePointers(expected, actual) {
 		return Fail(t, fmt.Sprintf("Not same: \n"+
 			"expected: %p %#v\n"+
 			"actual  : %p %#v", expected, expected, actual, actual), msgAndArgs...)
@@ -382,6 +385,42 @@
 	return true
 }
 
+// NotSame asserts that two pointers do not reference the same object.
+//
+//    assert.NotSame(t, ptr1, ptr2)
+//
+// Both arguments must be pointer variables. Pointer variable sameness is
+// determined based on the equality of both type and value.
+func NotSame(t TestingT, expected, actual interface{}, msgAndArgs ...interface{}) bool {
+	if h, ok := t.(tHelper); ok {
+		h.Helper()
+	}
+
+	if samePointers(expected, actual) {
+		return Fail(t, fmt.Sprintf(
+			"Expected and actual point to the same object: %p %#v",
+			expected, expected), msgAndArgs...)
+	}
+	return true
+}
+
+// samePointers compares two generic interface objects and returns whether
+// they point to the same object
+func samePointers(first, second interface{}) bool {
+	firstPtr, secondPtr := reflect.ValueOf(first), reflect.ValueOf(second)
+	if firstPtr.Kind() != reflect.Ptr || secondPtr.Kind() != reflect.Ptr {
+		return false
+	}
+
+	firstType, secondType := reflect.TypeOf(first), reflect.TypeOf(second)
+	if firstType != secondType {
+		return false
+	}
+
+	// compare pointer addresses
+	return first == second
+}
+
 // formatUnequalValues takes two values of arbitrary types and returns string
 // representations appropriate to be presented to the user.
 //
@@ -393,9 +432,11 @@
 		return fmt.Sprintf("%T(%#v)", expected, expected),
 			fmt.Sprintf("%T(%#v)", actual, actual)
 	}
-
-	return fmt.Sprintf("%#v", expected),
-		fmt.Sprintf("%#v", actual)
+	switch expected.(type) {
+	case time.Duration:
+		return fmt.Sprintf("%v", expected), fmt.Sprintf("%v", actual)
+	}
+	return fmt.Sprintf("%#v", expected), fmt.Sprintf("%#v", actual)
 }
 
 // EqualValues asserts that two objects are equal or convertable to the same types
@@ -901,15 +942,17 @@
 type PanicTestFunc func()
 
 // didPanic returns true if the function passed to it panics. Otherwise, it returns false.
-func didPanic(f PanicTestFunc) (bool, interface{}) {
+func didPanic(f PanicTestFunc) (bool, interface{}, string) {
 
 	didPanic := false
 	var message interface{}
+	var stack string
 	func() {
 
 		defer func() {
 			if message = recover(); message != nil {
 				didPanic = true
+				stack = string(debug.Stack())
 			}
 		}()
 
@@ -918,7 +961,7 @@
 
 	}()
 
-	return didPanic, message
+	return didPanic, message, stack
 
 }
 
@@ -930,7 +973,7 @@
 		h.Helper()
 	}
 
-	if funcDidPanic, panicValue := didPanic(f); !funcDidPanic {
+	if funcDidPanic, panicValue, _ := didPanic(f); !funcDidPanic {
 		return Fail(t, fmt.Sprintf("func %#v should panic\n\tPanic value:\t%#v", f, panicValue), msgAndArgs...)
 	}
 
@@ -946,12 +989,34 @@
 		h.Helper()
 	}
 
-	funcDidPanic, panicValue := didPanic(f)
+	funcDidPanic, panicValue, panickedStack := didPanic(f)
 	if !funcDidPanic {
 		return Fail(t, fmt.Sprintf("func %#v should panic\n\tPanic value:\t%#v", f, panicValue), msgAndArgs...)
 	}
 	if panicValue != expected {
-		return Fail(t, fmt.Sprintf("func %#v should panic with value:\t%#v\n\tPanic value:\t%#v", f, expected, panicValue), msgAndArgs...)
+		return Fail(t, fmt.Sprintf("func %#v should panic with value:\t%#v\n\tPanic value:\t%#v\n\tPanic stack:\t%s", f, expected, panicValue, panickedStack), msgAndArgs...)
+	}
+
+	return true
+}
+
+// PanicsWithError asserts that the code inside the specified PanicTestFunc
+// panics, and that the recovered panic value is an error that satisfies the
+// EqualError comparison.
+//
+//   assert.PanicsWithError(t, "crazy error", func(){ GoCrazy() })
+func PanicsWithError(t TestingT, errString string, f PanicTestFunc, msgAndArgs ...interface{}) bool {
+	if h, ok := t.(tHelper); ok {
+		h.Helper()
+	}
+
+	funcDidPanic, panicValue, panickedStack := didPanic(f)
+	if !funcDidPanic {
+		return Fail(t, fmt.Sprintf("func %#v should panic\n\tPanic value:\t%#v", f, panicValue), msgAndArgs...)
+	}
+	panicErr, ok := panicValue.(error)
+	if !ok || panicErr.Error() != errString {
+		return Fail(t, fmt.Sprintf("func %#v should panic with error message:\t%#v\n\tPanic value:\t%#v\n\tPanic stack:\t%s", f, errString, panicValue, panickedStack), msgAndArgs...)
 	}
 
 	return true
@@ -965,8 +1030,8 @@
 		h.Helper()
 	}
 
-	if funcDidPanic, panicValue := didPanic(f); funcDidPanic {
-		return Fail(t, fmt.Sprintf("func %#v should not panic\n\tPanic value:\t%v", f, panicValue), msgAndArgs...)
+	if funcDidPanic, panicValue, panickedStack := didPanic(f); funcDidPanic {
+		return Fail(t, fmt.Sprintf("func %#v should not panic\n\tPanic value:\t%v\n\tPanic stack:\t%s", f, panicValue, panickedStack), msgAndArgs...)
 	}
 
 	return true
@@ -1026,7 +1091,7 @@
 
 // InDelta asserts that the two numerals are within delta of each other.
 //
-// 	 assert.InDelta(t, math.Pi, (22 / 7.0), 0.01)
+// 	 assert.InDelta(t, math.Pi, 22/7.0, 0.01)
 func InDelta(t TestingT, expected, actual interface{}, delta float64, msgAndArgs ...interface{}) bool {
 	if h, ok := t.(tHelper); ok {
 		h.Helper()
@@ -1314,7 +1379,8 @@
 	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.
+// 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 {
 	if h, ok := t.(tHelper); ok {
 		h.Helper()
@@ -1332,7 +1398,24 @@
 	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.
+// NoFileExists checks whether a file does not exist in a given path. It fails
+// if the path points to an existing _file_ only.
+func NoFileExists(t TestingT, path string, msgAndArgs ...interface{}) bool {
+	if h, ok := t.(tHelper); ok {
+		h.Helper()
+	}
+	info, err := os.Lstat(path)
+	if err != nil {
+		return true
+	}
+	if info.IsDir() {
+		return true
+	}
+	return Fail(t, fmt.Sprintf("file %q exists", path), msgAndArgs...)
+}
+
+// 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 {
 	if h, ok := t.(tHelper); ok {
 		h.Helper()
@@ -1350,6 +1433,25 @@
 	return true
 }
 
+// NoDirExists checks whether a directory does not exist in the given path.
+// It fails if the path points to an existing _directory_ only.
+func NoDirExists(t TestingT, path string, msgAndArgs ...interface{}) bool {
+	if h, ok := t.(tHelper); ok {
+		h.Helper()
+	}
+	info, err := os.Lstat(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return true
+		}
+		return true
+	}
+	if !info.IsDir() {
+		return true
+	}
+	return Fail(t, fmt.Sprintf("directory %q exists", path), msgAndArgs...)
+}
+
 // JSONEq asserts that two JSON strings are equivalent.
 //
 //  assert.JSONEq(t, `{"hello": "world", "foo": "bar"}`, `{"foo": "bar", "hello": "world"}`)
@@ -1439,15 +1541,6 @@
 	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
@@ -1475,24 +1568,59 @@
 		h.Helper()
 	}
 
+	ch := make(chan bool, 1)
+
 	timer := time.NewTimer(waitFor)
-	ticker := time.NewTicker(tick)
-	checkPassed := make(chan bool)
 	defer timer.Stop()
+
+	ticker := time.NewTicker(tick)
 	defer ticker.Stop()
-	defer close(checkPassed)
-	for {
+
+	for tick := ticker.C; ; {
 		select {
 		case <-timer.C:
 			return Fail(t, "Condition never satisfied", msgAndArgs...)
-		case result := <-checkPassed:
-			if result {
+		case <-tick:
+			tick = nil
+			go func() { ch <- condition() }()
+		case v := <-ch:
+			if v {
 				return true
 			}
-		case <-ticker.C:
-			go func() {
-				checkPassed <- condition()
-			}()
+			tick = ticker.C
+		}
+	}
+}
+
+// Never asserts that the given condition doesn't satisfy in waitFor time,
+// periodically checking the target function each tick.
+//
+//    assert.Never(t, func() bool { return false; }, time.Second, 10*time.Millisecond)
+func Never(t TestingT, condition func() bool, waitFor time.Duration, tick time.Duration, msgAndArgs ...interface{}) bool {
+	if h, ok := t.(tHelper); ok {
+		h.Helper()
+	}
+
+	ch := make(chan bool, 1)
+
+	timer := time.NewTimer(waitFor)
+	defer timer.Stop()
+
+	ticker := time.NewTicker(tick)
+	defer ticker.Stop()
+
+	for tick := ticker.C; ; {
+		select {
+		case <-timer.C:
+			return true
+		case <-tick:
+			tick = nil
+			go func() { ch <- condition() }()
+		case v := <-ch:
+			if v {
+				return Fail(t, "Condition satisfied", msgAndArgs...)
+			}
+			tick = ticker.C
 		}
 	}
 }
diff --git a/vendor/github.com/stretchr/testify/assert/forward_assertions.go b/vendor/github.com/stretchr/testify/assert/forward_assertions.go
index 9ad5685..df189d2 100644
--- a/vendor/github.com/stretchr/testify/assert/forward_assertions.go
+++ b/vendor/github.com/stretchr/testify/assert/forward_assertions.go
@@ -13,4 +13,4 @@
 	}
 }
 
-//go:generate go run ../_codegen/main.go -output-package=assert -template=assertion_forward.go.tmpl -include-format-funcs
+//go:generate sh -c "cd ../_codegen && go build && cd - && ../_codegen/_codegen -output-package=assert -template=assertion_forward.go.tmpl -include-format-funcs"