feat: add filename validation to newArticles command

src/commands/newArticles.ts

@@ -1,18 +1,28 @@
 import arg from "arg";
 import { getFileSystemRepo } from "../lib/get-file-system-repo";
+import { validateFilename } from "../lib/filename-validator";
 
 export const newArticles = async (argv: string[]) => {
   const args = arg({}, { argv });
 
   const fileSystemRepo = await getFileSystemRepo();
+  let hasErrors = false;
 
   if (args._.length > 0) {
     for (const basename of args._) {
+      const validation = validateFilename(basename);
+      if (!validation.isValid) {
+        console.error(`Error: ${validation.error}`);
+        hasErrors = true;
+        continue;
+      }
+
       const createdFileName = await fileSystemRepo.createItem(basename);
       if (createdFileName) {
         console.log(`created: ${createdFileName}.md`);
       } else {
         console.error(`Error: '${basename}.md' is already exist`);
+        hasErrors = true;
       }
     }
   } else {
@@ -21,6 +31,11 @@ export const newArticles = async (argv: string[]) => {
       console.log(`created: ${createdFileName}.md`);
     } else {
       console.error("Error: failed to create");
+      hasErrors = true;
     }
   }
+
+  if (hasErrors) {
+    process.exitCode = 1;
+  }
 };

src/lib/filename-validator.test.ts

@@ -0,0 +1,58 @@
+import {
+  validateFilename,
+  ERROR_FILENAME_EMPTY,
+  ERROR_INVALID_CHARACTERS,
+  ERROR_INVALID_START_END,
+} from "./filename-validator";
+
+describe("validateFilename", () => {
+  it.each([
+    "test",
+    "test-article",
+    "test_article",
+    "test123",
+    "記事テスト",
+    "article.backup",
+    "my-awesome-article",
+    "test file",
+  ])("should accept valid filename '%s'", (name) => {
+    const result = validateFilename(name);
+    expect(result.isValid).toBe(true);
+    expect(result.error).toBeUndefined();
+  });
+
+  it.each(["", " ", "  ", "\t", "\n"])(
+    "should reject empty or whitespace-only filename '%s'",
+    (name) => {
+      const result = validateFilename(name);
+      expect(result.isValid).toBe(false);
+      expect(result.error).toBe(ERROR_FILENAME_EMPTY);
+    },
+  );
+
+  it.each([
+    "test<file",
+    "test>file",
+    "test:file",
+    'test"file',
+    "test/file",
+    "test\\file",
+    "test|file",
+    "test?file",
+    "test*file",
+    "test\x00file",
+  ])("should reject filename with invalid characters '%s'", (name) => {
+    const result = validateFilename(name);
+    expect(result.isValid).toBe(false);
+    expect(result.error).toBe(ERROR_INVALID_CHARACTERS);
+  });
+
+  it.each([".test", "test.", " test", "test ", "..test", "test.."])(
+    "should reject filename starting or ending with dots or spaces '%s'",
+    (name) => {
+      const result = validateFilename(name);
+      expect(result.isValid).toBe(false);
+      expect(result.error).toBe(ERROR_INVALID_START_END);
+    },
+  );
+});

src/lib/filename-validator.ts

@@ -0,0 +1,40 @@
+// eslint-disable-next-line no-control-regex -- include control characters
+const INVALID_FILENAME_CHARS = /[<>:"/\\|?*\x00-\x1f]/;
+
+export const ERROR_FILENAME_EMPTY = "Filename is empty";
+export const ERROR_INVALID_CHARACTERS =
+  'Filename contains invalid characters: < > : " / \\ | ? * and control characters';
+export const ERROR_INVALID_START_END =
+  "Filename cannot start or end with a dot or space";
+
+export interface FilenameValidationResult {
+  isValid: boolean;
+  error?: string;
+}
+
+export function validateFilename(filename: string): FilenameValidationResult {
+  if (!filename || filename.trim().length === 0) {
+    return {
+      isValid: false,
+      error: ERROR_FILENAME_EMPTY,
+    };
+  }
+
+  if (INVALID_FILENAME_CHARS.test(filename)) {
+    return {
+      isValid: false,
+      error: ERROR_INVALID_CHARACTERS,
+    };
+  }
+
+  if (/^[. ]|[. ]$/.test(filename)) {
+    return {
+      isValid: false,
+      error: ERROR_INVALID_START_END,
+    };
+  }
+
+  return {
+    isValid: true,
+  };
+}