Features - Help | JetBrains Rider

Editor tips

JetBrains Rider marks classes, methods and fields that are implicitly used by Unity directly in the editor.
The UnityEngine.Color and UnityEngine.Color32 colors are highlighted, and hitting Alt+Enter will open the colour palette editor to modify the color. Also named colours and Color.HSVToRGB are supported.

You can generate event functions using Unity Event Functions the Generate Code menu (Alt+Insert). This action is also available from Alt+Enter on a Unity-based class' name.
Auto-completion will suggest event function names when declaring methods in Unity-based classes, and expand to include method signature. Simply start typing an event function within a class deriving from a known Unity class, such as MonoBehaviour.
Descriptions for event functions and parameters in Unity based classes are shown in tooltips and Quick Documentation.

When the Solution-Wide Analysis is enabled, JetBrains Rider understands implicitly used fields and event functions and do not highlight them as not accessed.
Empty event functions are shown as dead code, with a quick-fix to remove them.
Using the SyncVarAttribute inside any class other than NetworkBehaviour is treated as an error.
A quick-fix is suggested to create a serialized field from a usage of an unresolved symbol:
JetBrains Rider ensures that all of your event functions have correct signatures: it highlights incorrect signatures and offers a quick-fix to correct them:
JetBrains Rider warns you against using an inefficient string literal comparison with the tag property, and provides a quick-fix to rewrite this as a call to CompareTag.
JetBrains Rider warns you if you try to use the new keyword to create a new instance of a class deriving from MonoBehaviour or ScriptableObject. A quick-fix is suggested to use gameObject.AddComponent<T>() or ScriptableObject.CreateInstance<T>() instead.
There are also inspections for the [InitializeOnLoad] and [InitializeOnLoadMethod] attributes, ensuring that they have the correct method or constructor signatures, and JetBrains Rider will grey out a redundant [InitializeOnLoad] attribute if the class doesn't have a static constructor, with a quick-fix to either quickly remove the attribute, or create the constructor.

A lot of Unity-specific assemblies are annotated with External Annotations to improve code inspection when you make use of these assemblies.

Treating code marked with attributes from UnityEngine.dll, UnityEngine.Networking.dll and UnityEditor.dll as implicitly used.
Marking Component.gameObject and Object.name as not-nullable.
Debug.Assert marked as assertion method to help null-value analysis (e.g. "value cannot be null" after Debug.Assert(x != null)).
Debug.AssertFormat, LogFormat, etc. gets string formatting helper functionality.
Assertions.Assert methods marked as assertion methods to help null-value analysis.
EditorTestsWithLogParser.ExpectLogLineRegex gets regular expression helper functionality.
Various attributes now require the class they are applied to derive from a specific base type. E.g. [CustomEditor] requires a base class of Editor.
Support for Unity 2017.2's modularised UnityEngine assemblies.

JetBrains Rider provides the initial support for ShaderLab syntax in .shader files, with limited support for Cg/HLSL blocks.

Syntax and syntax error highlighting for ShaderLab syntax.
Color Assistance:
JetBrains Rider provides simple completion based on words found in the current file.
Brace matching and highlighting, comment/uncomment (Ctrl+Alt+/), and to-do explorer support.
Code folding.
[Cg/HLSL] Syntax highlighting for CGPROGRAM/ CGINCLUDE blocks and .cginc files.
[Cg/HLSL] Simple word based completion in Cg/HLSL blocks.

JetBrains Rider offers a number of file templates for new C# script, tests, and shader files: