Add InlayHints to the specification.

_data/linkableTypes.yml

@@ -707,4 +707,20 @@
   - type: 'MonikerKind'
     link: '#monikerKind'
   - type: 'Moniker'
-    link: '#moniker'
+    link: '#moniker'
+  - type: 'InlayHintClientCapabilities'
+    link: '#inlayHintClientCapabilities'
+  - type: 'InlayHintOptions'
+    link: '#inlayHintOptions'
+  - type: 'InlayHintRegistrationOptions'
+    link: '#inlayHintRegistrationOptions'
+  - type: 'InlayHintParams'
+    link: '#inlayHintParams'
+  - type: 'InlayHint'
+    link: '#inlayHint'
+  - type: 'InlayHintLabelPart'
+    link: '#inlayHintLabelPart'
+  - type: 'InlayHintKind'
+    link: '#inlayHintKind'
+  - type: 'InlayHintWorkspaceClientCapabilities'
+    link: '#inlayHintWorkspaceClientCapabilities'

_data/specification-3-17-toc.yml

@@ -167,6 +167,12 @@
       anchor: textDocument_documentSymbol
     - title: Semantic Tokens
       anchor: textDocument_semanticTokens
+    - title: Inlay Hint
+      anchor: textDocument_inlayHint
+    - title: Inlay Hint Resolve
+      anchor: inlayHint_resolve
+    - title: Inlay Hint Refresh
+      anchor: workspace_inlayHint_refresh
     - title: Moniker
       anchor: textDocument_moniker
     - title: Completion Proposals

_specifications/lsp/3.17/language/inlayHint.md

@@ -0,0 +1,316 @@
+#### <a href="#textDocument_inlayHint" name="textDocument_inlayHint" class="anchor">Inlay Hint Request (:leftwards_arrow_with_hook:)</a>
+
+> *Since version 3.17.0*
+
+The inlay hints request is sent from the client to the server to compute inlay hints for a given [text document, range] tuple that may be rendered in the editor in place with other text.
+
+_Client Capability_:
+* property name (optional): `textDocument.inlayHint`
+* property type: `InlayHintClientCapabilities` defined as follows:
+
+<div class="anchorHolder"><a href="#inlayHintClientCapabilities" name="inlayHintClientCapabilities" class="linkableAnchor"></a></div>
+
+```typescript
+/**
+ * Inlay hint client capabilities.
+ *
+ * @since 3.17.0 - proposed state
+ */
+export type InlayHintClientCapabilities = {
+
+	/**
+	 * Whether inlay hints support dynamic registration.
+	 */
+	dynamicRegistration?: boolean;
+
+	/**
+	 * Indicates which properties a client can resolve lazily on a inlay
+	 * hint.
+	 */
+	resolveSupport?: {
+
+		/**
+		 * The properties that a client can resolve lazily.
+		 */
+		properties: string[];
+	};
+};
+```
+
+_Server Capability_:
+* property name (optional): `inlayHintProvider`
+* property type: `InlayHintOptions` defined as follows:
+
+<div class="anchorHolder"><a href="#inlayHintOptions" name="inlayHintOptions" class="linkableAnchor"></a></div>
+
+```typescript
+/**
+ * Inlay hint options used during static registration.
+ *
+ * @since 3.17.0 - proposed state
+ */
+export type InlayHintOptions = WorkDoneProgressOptions & {
+	/**
+	 * The server provides support to resolve additional
+	 * information for an inlay hint item.
+	 */
+	resolveProvider?: boolean;
+};
+```
+
+_Registration Options_: `InlayHintRegistrationOptions` defined as follows:
+
+<div class="anchorHolder"><a href="#inlayHintRegistrationOptions" name="inlayHintRegistrationOptions" class="linkableAnchor"></a></div>
+
+```typescript
+/**
+ * Inlay hint options used during static or dynamic registration.
+ *
+ * @since 3.17.0 - proposed state
+ */
+export type InlayHintRegistrationOptions = InlayHintsOptions
+	& TextDocumentRegistrationOptions & StaticRegistrationOptions;
+```
+
+_Request_:
+* method: `textDocument/inlayHint`
+* params: `InlayHintParams` defined as follows:
+
+<div class="anchorHolder"><a href="#inlayHintParams" name="inlayHintParams" class="linkableAnchor"></a></div>
+
+```typescript
+/**
+ * A parameter literal used in inlay hint requests.
+ *
+ * @since 3.17.0 - proposed state
+ */
+export type InlayHintParams = WorkDoneProgressParams & {
+	/**
+	 * The text document.
+	 */
+	textDocument: TextDocumentIdentifier;
+
+	/**
+	 * The visible document range for which inlay hints should be computed.
+	 */
+	range: Range;
+};
+```
+
+_Response_:
+* result: `InlayHint[]` \| `null` defined as follows:
+
+<div class="anchorHolder"><a href="#inlayHint" name="inlayHint" class="linkableAnchor"></a></div>
+
+```typescript
+/**
+ * Inlay hint information.
+ *
+ * @since 3.17.0 - proposed state
+ */
+export type InlayHint = {
+
+	/**
+	 * The position of this hint.
+	 */
+	position: Position;
+
+	/**
+	 * The label of this hint. A human readable string or an array of
+	 * InlayHintLabelPart label parts.
+	 *
+	 * *Note* that neither the string nor the label part can be empty.
+	 */
+	label: string | InlayHintLabelPart[];
+
+	/**
+	 * The kind of this hint. Can be omitted in which case the client
+	 * should fall back to a reasonable default.
+	 */
+	kind?: InlayHintKind;
+
+	/**
+	 * Optional text edits that are performed when accepting this inlay hint.
+	 *
+	 * *Note* that edits are expected to change the document so that the inlay
+	 * hint (or its nearest variant) is now part of the document and the inlay
+	 * hint itself is now obsolete.
+	 *
+	 * Depending on the client capability `inlayHint.resolveSupport` clients
+	 * might resolve this property late using the resolve request.
+	 */
+	textEdits?: TextEdit[];
+
+	/**
+	 * The tooltip text when you hover over this item.
+	 *
+	 * Depending on the client capability `inlayHint.resolveSupport` clients
+	 * might resolve this property late using the resolve request.
+	 */
+	tooltip?: string | MarkupContent;
+
+	/**
+	 * Render padding before the hint.
+	 *
+	 * Note: Padding should use the editor's background color, not the
+	 * background color of the hint itself. That means padding can be used
+	 * to visually align/separate an inlay hint.
+	 */
+	paddingLeft?: boolean;
+
+	/**
+	 * Render padding after the hint.
+	 *
+	 * Note: Padding should use the editor's background color, not the
+	 * background color of the hint itself. That means padding can be used
+	 * to visually align/separate an inlay hint.
+	 */
+	paddingRight?: boolean;
+
+
+	/**
+	 * A data entry field that is preserved on a inlay hint between
+	 * a `textDocument/inlayHint` and a `inlayHint/resolve` request.
+	 */
+	data?: LSPAny;
+};
+```
+
+<div class="anchorHolder"><a href="#inlayHintLabelPart" name="inlayHintLabelPart" class="linkableAnchor"></a></div>
+
+```typescript
+/**
+ * An inlay hint label part allows for interactive and composite labels
+ * of inlay hints.
+ *
+ * @since 3.17.0 - proposed state
+ */
+export type InlayHintLabelPart = {
+
+	/**
+	 * The value of this label part.
+	 */
+	value: string;
+
+	/**
+	 * The tooltip text when you hover over this label part. Depending on
+	 * the client capability `inlayHint.resolveSupport` clients might resolve
+	 * this property late using the resolve request.
+	 */
+	tooltip?: string | MarkupContent;
+
+	/**
+	 * An optional source code location that represents this
+	 * label part.
+	 *
+	 * The editor will use this location for the hover and for code navigation
+	 * features: This part will become a clickable link that resolves to the
+	 * definition of the symbol at the given location (not necessarily the
+	 * location itself), it shows the hover that shows at the given location,
+	 * and it shows a context menu with further code navigation commands.
+	 *
+	 * Depending on the client capability `inlayHint.resolveSupport` clients
+	 * might resolve this property late using the resolve request.
+	 */
+	location?: Location;
+
+	/**
+	 * An optional command for this label part.
+	 *
+	 * Depending on the client capability `inlayHint.resolveSupport` clients
+	 * might resolve this property late using the resolve request.
+	 */
+	command?: Command;
+};
+```
+
+<div class="anchorHolder"><a href="#inlayHintKind" name="inlayHintKind" class="linkableAnchor"></a></div>
+
+```typescript
+/**
+ * Inlay hint kinds.
+ *
+ * @since 3.17.0 - proposed state
+ */
+export namespace InlayHintKind {
+
+	/**
+	 * An inlay hint that for a type annotation.
+	 */
+	export const Type = 1;
+
+	/**
+	 * An inlay hint that is for a parameter.
+	 */
+	export const Parameter = 2;
+};
+```
+
+* error: code and message set in case an exception happens during the inlay hint request.
+
+#### <a href="#inlayHint_resolve" name="inlayHint_resolve" class="anchor">Inlay Hint Resolve Request (:leftwards_arrow_with_hook:)</a>
+
+The request is sent from the client to the server to resolve additional information for a given inlay hint. This is usually used to compute
+the `tooltip`, `location` or `command` properties of a inlay hint's label part to avoid its unnecessary computation during the `textDocument/inlayHint` request.
+
+Consider the clients announces the `label.location` property as a property that can be resolved lazy using the client capability
+
+```typescript
+textDocument.inlayHint.resolveSupport = { properties: ['label.location'] };
+```
+
+then an inlay hint with a label part without a location needs to be resolved using the `inlayHint/resolve` request before it can be used.
+
+_Client Capability_:
+* property name (optional): `textDocument.inlayHint.resolveSupport`
+* property type: `{ properties: string[]; }`
+
+_Request_:
+* method: `inlayHint/resolve`
+* params: `InlayHint`
+
+_Response_:
+* result: `InlayHint`
+* error: code and message set in case an exception happens during the completion resolve request.
+
+#### <a href="#workspace_inlayHint_refresh" name="workspace_inlayHint_refresh" class="anchor">Inlay Hint Refresh Request  (:arrow_right_hook:)</a>
+
+> *Since version 3.17.0*
+
+The `workspace/inlayHint/refresh` request is sent from the server to the client. Servers can use it to ask clients to refresh the inlay hints currently shown in editors. As a result the client should ask the server to recompute the inlay hints for these editors. This is useful if a server detects a configuration change which requires a re-calculation of all inlay hints. Note that the client still has the freedom to delay the re-calculation of the inlay hints if for example an editor is currently not visible.
+
+_Client Capability_:
+
+* property name (optional): `workspace.inlayHint`
+* property type: `InlayHintWorkspaceClientCapabilities` defined as follows:
+
+<div class="anchorHolder"><a href="#inlayHintWorkspaceClientCapabilities" name="inlayHintWorkspaceClientCapabilities" class="linkableAnchor"></a></div>
+
+```typescript
+/**
+ * Client workspace capabilities specific to inlay hints.
+ *
+ * @since 3.17.0 - proposed state
+ */
+export type InlayHintWorkspaceClientCapabilities = {
+	/**
+	 * Whether the client implementation supports a refresh request sent from
+	 * the server to the client.
+	 *
+	 * Note that this event is global and will force the client to refresh all
+	 * inlay hints currently shown. It should be used with absolute care and
+	 * is useful for situation where a server for example detects a project wide
+	 * change that requires such a calculation.
+	 */
+	refreshSupport?: boolean;
+};
+```
+
+_Request_:
+* method: `workspace/inlayHint/refresh`
+* params: none
+
+_Response_:
+
+* result: void
+* error: code and message set in case an exception happens during the 'workspace/inlayHint/refresh' request

_specifications/lsp/3.17/specification.md

@@ -663,6 +663,7 @@ Language Feature provide the actual smarts in the language server protocol. The
 {% include_relative language/selectionRange.md %}
 {% include_relative language/documentSymbol.md %}
 {% include_relative language/semanticTokens.md %}
+{% include_relative language/inlayHint.md %}
 {% include_relative language/moniker.md %}
 {% include_relative language/completion.md %}
 {% include_relative language/publishDiagnostics.md %}