PLT-1378 Initial version of emoji reactions (#4520)

* Refactored emoji.json to support multiple aliases and emoji categories

* Added custom category to emoji.jsx and stabilized all fields

* Removed conflicting aliases for :mattermost: and :ca:

* fixup after store changes

* Added emoji reactions

* Removed reactions for an emoji when that emoji is deleted

* Fixed incorrect test case

* Renamed ReactionList to ReactionListView

* Fixed 👍 and 👎 not showing up as possible reactions

* Removed text emoticons from emoji reaction autocomplete

* Changed emoji reactions to be sorted by the order that they were first created

* Set a maximum number of listeners for the ReactionStore

* Removed unused code from Textbox component

* Fixed reaction permissions

* Changed error code when trying to modify reactions for another user

* Fixed merge conflicts

* Properly applied theme colours to reactions

* Fixed ESLint and gofmt errors

* Fixed ReactionListContainer to properly update when its post prop changes

* Removed unnecessary escape characters from reaction regexes

* Shared reaction message pattern between CreatePost and CreateComment

* Removed an unnecessary select query when saving a reaction

* Changed reactions route to be under /reactions

* Fixed copyright dates on newly added files

* Removed debug code that prevented all unit tests from being ran

* Cleaned up unnecessary code for reactions

* Renamed ReactionStore.List to ReactionStore.GetForPost

model/reaction_test.go

@@ -0,0 +1,64 @@
+// Copyright (c) 2016 Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
+package model
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestReactionIsValid(t *testing.T) {
+	reaction := Reaction{
+		UserId:    NewId(),
+		PostId:    NewId(),
+		EmojiName: "emoji",
+		CreateAt:  GetMillis(),
+	}
+
+	if err := reaction.IsValid(); err != nil {
+		t.Fatal(err)
+	}
+
+	reaction.UserId = ""
+	if err := reaction.IsValid(); err == nil {
+		t.Fatal("user id should be invalid")
+	}
+
+	reaction.UserId = "1234garbage"
+	if err := reaction.IsValid(); err == nil {
+		t.Fatal("user id should be invalid")
+	}
+
+	reaction.UserId = NewId()
+	reaction.PostId = ""
+	if err := reaction.IsValid(); err == nil {
+		t.Fatal("post id should be invalid")
+	}
+
+	reaction.PostId = "1234garbage"
+	if err := reaction.IsValid(); err == nil {
+		t.Fatal("post id should be invalid")
+	}
+
+	reaction.PostId = NewId()
+	reaction.EmojiName = ""
+	if err := reaction.IsValid(); err == nil {
+		t.Fatal("emoji name should be invalid")
+	}
+
+	reaction.EmojiName = strings.Repeat("a", 65)
+	if err := reaction.IsValid(); err == nil {
+		t.Fatal("emoji name should be invalid")
+	}
+
+	reaction.EmojiName = strings.Repeat("a", 64)
+	if err := reaction.IsValid(); err != nil {
+		t.Fatal(err)
+	}
+
+	reaction.CreateAt = 0
+	if err := reaction.IsValid(); err == nil {
+		t.Fatal("create at should be invalid")
+	}
+}