Update mattermost library (#2152)

* Update mattermost library

* Fix linting

vendor/github.com/wiggin77/merror/.travis.yml

@@ -1,5 +0,0 @@
-language: go
-sudo: false
-before_script:
-  - go vet ./...
-  

vendor/github.com/wiggin77/merror/README.md

@@ -1,6 +1,47 @@
 # merror
 
 [![GoDoc](https://godoc.org/github.com/wiggin77/merror?status.svg)](https://godoc.org/github.com/wiggin77/merror)
-[![Build Status](https://travis-ci.org/wiggin77/merror.svg?branch=master)](https://travis-ci.org/wiggin77/merror)
+![Build Status](https://github.com/wiggin77/merror/actions/workflows/ci.yml/badge.svg?event=push)
 
 Multiple Error aggregator for Go.
+
+## Usage
+
+```go
+func foo() error {
+  merr := merror.New()
+
+  if err := DoSomething(); err != nil {
+    merr.Append(err)
+  }
+
+  return merr.ErrorOrNil()
+}
+```
+
+A bounded `merror` can be used to guard against memory ballooning.
+
+```go
+func bar() error {
+  merr := merror.NewWithCap(10)
+
+  for i := 0; i < 15; i++ {
+    if err := DoSomething(); err != nil {
+      merr.Append(err)
+    }
+  }
+
+  fmt.Printf("Len: %d,  Overflow: %d", merr.Len(), merr.Overflow()) 
+  // Len: 10,  Overflow: 5
+
+  return merr.ErrorOrNil()
+}
+```
+
+## errors.Is
+
+If any of the errors appended to a `merror` match the target error passed to `errors.Is(err, target error)` then true is returned.
+
+## errors.As
+
+If any of the errors appended to a `merror` match the target type passed to `errors.As(err error, target any)` then true is returned and the target is set to the matching error.

vendor/github.com/wiggin77/merror/append.go

@@ -0,0 +1,25 @@
+package merror
+
+// Append an error to a multi-error.
+// If `to` is `nil` it will just assign `err`.
+// If `to` is not a `*MError` it will create a new `*MError` and append both errors.
+// If `err` is `nil` it will just return `to`.
+// Otherwise it will just append to the existing `*MError`.
+func Append(to, err error) error {
+	if err == nil {
+		return to
+	}
+	if to == nil {
+		return err
+	}
+
+	if merr, ok := to.(*MError); ok {
+		merr.Append(err)
+		return merr
+	}
+
+	merr := New()
+	merr.Append(to)
+	merr.Append(err)
+	return merr
+}

vendor/github.com/wiggin77/merror/merror.go

@@ -1,6 +1,9 @@
 package merror
 
-import "sync"
+import (
+	"errors"
+	"sync"
+)
 
 // MError represents zero or more errors that can be
 // accumulated via the `Append` method.
@@ -34,18 +37,20 @@ func NewWithCap(cap int) *MError {
 }
 
 // Append adds an error to the aggregated error list.
-func (me *MError) Append(err error) {
-	if err == nil {
+func (me *MError) Append(errs ...error) {
+	if len(errs) == 0 {
 		return
 	}
 
 	me.mux.Lock()
 	defer me.mux.Unlock()
 
-	if me.cap > 0 && len(me.errors) >= me.cap {
-		me.overflow++
-	} else {
-		me.errors = append(me.errors, err)
+	for _, err := range errs {
+		if me.cap > 0 && len(me.errors) >= me.cap {
+			me.overflow++
+		} else {
+			me.errors = append(me.errors, err)
+		}
 	}
 }
 
@@ -118,3 +123,29 @@ func (me *MError) Error() string {
 	}
 	return f(me)
 }
+
+func (me *MError) Is(target error) bool {
+	me.mux.RLock()
+	defer me.mux.RUnlock()
+
+	for _, err := range me.errors {
+		if errors.Is(err, target) {
+			return true
+		}
+	}
+
+	return false
+}
+
+func (me *MError) As(target interface{}) bool {
+	me.mux.RLock()
+	defer me.mux.RUnlock()
+
+	for _, err := range me.errors {
+		if errors.As(err, target) {
+			return true
+		}
+	}
+
+	return false
+}