test: Fix codecov

Author: hyperupcall

src/converters/comments/convertFileComments.test.ts

@@ -6,7 +6,7 @@ import { createStubConverter } from "../lintConfigs/rules/ruleConverter.stubs";
 import { convertFileComments, ConvertFileCommentsDependencies } from "./convertFileComments";
 
 const createStubDependencies = (
-    readFileResult: string | Error,
+    readFileResult: string | NodeJS.ErrnoException,
 ): ConvertFileCommentsDependencies => ({
     converters: new Map([
         ["ts-a", createStubConverter(["es-a"])],
@@ -39,6 +39,24 @@ describe("convertFileComments", () => {
         expect(result).toBe(readFileError);
     });
 
+    it("ignores the failure when attempting to read a directory", async () => {
+        // Arrange
+        const readDirError = new Error() as NodeJS.ErrnoException;
+        readDirError.code = "EISDIR";
+        const dependencies = createStubDependencies(readDirError);
+
+        // Act
+        const result = await convertFileComments(
+            dependencies,
+            stubFileName,
+            new Map<string, string[]>(),
+            new Map<string, string[]>(),
+        );
+
+        // Assert
+        expect(result).toBe(undefined);
+    });
+
     it("doesn't overwrite a file when there are no matching comment directives", async () => {
         // Arrange
         const dependencies = createStubDependencies(`