fix: introduce utilities for v9 compatability

Author: G-Rath

lib/utils/compat.ts

@@ -0,0 +1,84 @@
+import { type TSESLint, type TSESTree } from '@typescript-eslint/utils';
+
+declare module '@typescript-eslint/utils/dist/ts-eslint/Rule' {
+  // eslint-disable-next-line @typescript-eslint/no-unused-vars
+  export interface RuleContext<TMessageIds extends string, TOptions extends readonly unknown[]> {
+    /**
+     * The filename associated with the source.
+     */
+    filename: string;
+
+    /**
+     * A SourceCode object that you can use to work with the source that
+     * was passed to ESLint.
+     */
+    sourceCode: Readonly<TSESLint.SourceCode>;
+  }
+}
+
+declare module '@typescript-eslint/utils/dist/ts-eslint/SourceCode' {
+  export interface SourceCode {
+    /**
+     * Returns the scope of the given node.
+     * This information can be used track references to variables.
+     * @since 8.37.0
+     */
+    getScope(node: TSESTree.Node): TSESLint.Scope.Scope;
+    /**
+     * Returns an array of the ancestors of the given node, starting at
+     * the root of the AST and continuing through the direct parent of the current node.
+     * This array does not include the currently-traversed node itself.
+     * @since 8.38.0
+     */
+    getAncestors(node: TSESTree.Node): TSESTree.Node[];
+    /**
+     * Returns a list of variables declared by the given node.
+     * This information can be used to track references to variables.
+     * @since 8.38.0
+     */
+    getDeclaredVariables(
+      node: TSESTree.Node,
+    ): readonly TSESLint.Scope.Variable[];
+  }
+}
+
+/* istanbul ignore next */
+export const getFilename = (
+  context: TSESLint.RuleContext<string, unknown[]>,
+) => {
+  return context.filename ?? context.getFilename();
+};
+
+/* istanbul ignore next */
+export const getSourceCode = (
+  context: TSESLint.RuleContext<string, unknown[]>,
+) => {
+  return context.sourceCode ?? context.getSourceCode();
+};
+
+/* istanbul ignore next */
+export const getScope = (
+  context: TSESLint.RuleContext<string, unknown[]>,
+  node: TSESTree.Node,
+) => {
+  return getSourceCode(context).getScope?.(node) ?? context.getScope();
+};
+
+/* istanbul ignore next */
+export const getAncestors = (
+  context: TSESLint.RuleContext<string, unknown[]>,
+  node: TSESTree.Node,
+) => {
+  return getSourceCode(context).getAncestors?.(node) ?? context.getAncestors();
+};
+
+/* istanbul ignore next */
+export const getDeclaredVariables = (
+  context: TSESLint.RuleContext<string, unknown[]>,
+  node: TSESTree.Node,
+) => {
+  return (
+    getSourceCode(context).getDeclaredVariables?.(node) ??
+    context.getDeclaredVariables(node)
+  );
+};

lib/utils/index.ts

@@ -1,3 +1,4 @@
+export * from './compat';
 export * from './file-import';
 export * from './types';