Fix definition of DiagnosticCallback. Fixes peggyjs#283.

CHANGELOG.md

@@ -27,7 +27,8 @@ Released: TBD
 
 ### Bug Fixes
 
-- None
+- [#283](https://github.com/peggyjs/peggy/issues/283) Fix incorrect type
+  information for DiagnosticCallback, from @hildjj
 
 2.0.1
 -----

lib/peg.d.ts

@@ -997,50 +997,20 @@ export interface Session {
   ): void;
 }
 
-export interface DiagnosticCallback {
-  /**
-   * Called when compiler reports an error.
-   *
-   * @param stage Stage in which this diagnostic was originated
-   * @param message Main message, which should describe error objectives
-   * @param location If defined, this is location described in the `message`
-   * @param notes Additional messages with context information
-   */
-  error?(
-    stage: Stage,
-    message: string,
-    location?: LocationRange,
-    notes?: DiagnosticNote[]
-  ): void;
-  /**
-   * Called when compiler reports a warning.
-   *
-   * @param stage Stage in which this diagnostic was originated
-   * @param message Main message, which should describe warning objectives
-   * @param location If defined, this is location described in the `message`
-   * @param notes Additional messages with context information
-   */
-  warning?(
-    stage: Stage,
-    message: string,
-    location?: LocationRange,
-    notes?: DiagnosticNote[]
-  ): void;
-  /**
-   * Called when compiler reports an informational message.
-   *
-   * @param stage Stage in which this diagnostic was originated
-   * @param message Main message, which gives information about an event
-   * @param location If defined, this is location described in the `message`
-   * @param notes Additional messages with context information
-   */
-  info?(
-    stage: Stage,
-    message: string,
-    location?: LocationRange,
-    notes?: DiagnosticNote[]
-  ): void;
-}
+/**
+ * Called when compiler reports an error, warning, or info.
+ *
+ * @param stage Stage in which this diagnostic was originated
+ * @param message Main message, which should describe error objectives
+ * @param location If defined, this is location described in the `message`
+ * @param notes Additional messages with context information
+ */
+export type DiagnosticCallback = (
+  stage: Stage,
+  message: string,
+  location?: LocationRange,
+  notes?: DiagnosticNote[]
+) => void;
 
 /**
  * Parser dependencies, is an object which maps variables used to access the