Feature: dir-letter-count option

src/modules/argumentsParser.ts

@@ -295,20 +295,29 @@ export default class ArgumentsParser {
       })
       .option('dir-letter', {
         group: groupRomOutput,
-        description: 'Append the first letter of the ROM name as an output subdirectory',
+        description: 'Group games in an output subdirectory by the first --dir-letter-count letters in their name',
         type: 'boolean',
       })
+      .option('dir-letter-count', {
+        group: groupRomOutput,
+        description: 'How many game name letters to use for the subdirectory name',
+        type: 'number',
+        coerce: (val: number) => Math.max(ArgumentsParser.getLastValue(val), 1),
+        requiresArg: true,
+        // Note: can't `implies: 'dir-letter'` with a default value set
+        default: 1,
+      })
       .option('dir-letter-limit', {
         group: groupRomOutput,
-        description: 'Limit the number ROMs in letter subdirectories, splitting into multiple if necessary',
+        description: 'Limit the number games in letter subdirectories, splitting into multiple subdirectories if necessary',
         type: 'number',
         coerce: (val: number) => Math.max(ArgumentsParser.getLastValue(val), 1),
         requiresArg: true,
         implies: 'dir-letter',
       })
       .option('dir-game-subdir', {
         group: groupRomOutput,
-        description: 'Append the name of the game as an output directory depending on its ROMs',
+        description: 'Append the name of the game as an output subdirectory depending on its ROMs',
         choices: Object.keys(GameSubdirMode)
           .filter((mode) => Number.isNaN(Number(mode)))
           .map((mode) => mode.toLowerCase()),

src/types/options.ts

@@ -66,6 +66,7 @@ export interface OptionsProps {
   readonly dirDatName?: boolean,
   readonly dirDatDescription?: boolean,
   readonly dirLetter?: boolean,
+  readonly dirLetterCount?: number,
   readonly dirLetterLimit?: number,
   readonly dirGameSubdir?: string,
   readonly overwrite?: boolean,
@@ -181,6 +182,8 @@ export default class Options implements OptionsProps {
 
   readonly dirLetter: boolean;
 
+  readonly dirLetterCount: number;
+
   readonly dirLetterLimit: number;
 
   readonly dirGameSubdir?: string;
@@ -333,6 +336,7 @@ export default class Options implements OptionsProps {
     this.dirDatName = options?.dirDatName ?? false;
     this.dirDatDescription = options?.dirDatDescription ?? false;
     this.dirLetter = options?.dirLetter ?? false;
+    this.dirLetterCount = options?.dirLetterCount ?? 0;
     this.dirLetterLimit = options?.dirLetterLimit ?? 0;
     this.dirGameSubdir = options?.dirGameSubdir;
     this.overwrite = options?.overwrite ?? false;
@@ -756,6 +760,10 @@ export default class Options implements OptionsProps {
     return this.dirLetter;
   }
 
+  getDirLetterCount(): number {
+    return this.dirLetterCount;
+  }
+
   getDirLetterLimit(): number {
     return this.dirLetterLimit;
   }

src/types/outputFactory.ts

@@ -328,14 +328,18 @@ export default class OutputFactory {
 
     // Find the letter for every ROM filename
     let lettersToFilenames = (romBasenames ?? [romBasename]).reduce((map, filename) => {
-      let letter = filename.charAt(0).toUpperCase();
-      if (letter.match(/[^A-Z]/)) {
-        letter = '#';
-      }
-
-      const existing = map.get(letter) ?? new Set();
+      const filenameParsed = path.parse(filename);
+      let letters = (filenameParsed.dir || filenameParsed.name)
+        .substring(0, options.getDirLetterCount())
+        .padEnd(options.getDirLetterCount(), 'A')
+        .toUpperCase()
+        .replace(/[^A-Z0-9]/g, '#');
+      // TODO(cemmer): only do this when not --dir-letter-group
+      letters = letters.replace(/[^A-Z]/g, '#');
+
+      const existing = map.get(letters) ?? new Set();
       existing.add(filename);
-      map.set(letter, existing);
+      map.set(letters, existing);
       return map;
     }, new Map<string, Set<string>>());
 

test/modules/argumentsParser.test.ts

@@ -111,6 +111,7 @@ describe('options', () => {
     expect(options.getDirDatName()).toEqual(false);
     expect(options.getDirDatDescription()).toEqual(false);
     expect(options.getDirLetter()).toEqual(false);
+    expect(options.getDirLetterCount()).toEqual(1);
     expect(options.getDirLetterLimit()).toEqual(0);
     expect(options.getDirGameSubdir()).toEqual(GameSubdirMode.MULTIPLE);
     expect(options.getOverwrite()).toEqual(false);
@@ -346,6 +347,14 @@ describe('options', () => {
     expect(argumentsParser.parse([...dummyCommandAndRequiredArgs, '--dir-letter', 'true', '--dir-letter', 'false']).getDirLetter()).toEqual(false);
   });
 
+  it('should parse "dir-letter-count"', () => {
+    expect(argumentsParser.parse([...dummyCommandAndRequiredArgs, '--dir-letter', '--dir-letter-count', '-1']).getDirLetterCount()).toEqual(1);
+    expect(argumentsParser.parse([...dummyCommandAndRequiredArgs, '--dir-letter', '--dir-letter-count', '0']).getDirLetterCount()).toEqual(1);
+    expect(argumentsParser.parse([...dummyCommandAndRequiredArgs, '--dir-letter', '--dir-letter-count', '1']).getDirLetterCount()).toEqual(1);
+    expect(argumentsParser.parse([...dummyCommandAndRequiredArgs, '--dir-letter', '--dir-letter-count', '5']).getDirLetterCount()).toEqual(5);
+    expect(argumentsParser.parse([...dummyCommandAndRequiredArgs, '--dir-letter', '--dir-letter-count', '5', '--dir-letter-count', '10']).getDirLetterCount()).toEqual(10);
+  });
+
   it('should parse "dir-letter-limit"', () => {
     expect(() => argumentsParser.parse([...dummyCommandAndRequiredArgs, '--dir-letter-limit'])).toThrow(/not enough arguments/i);
     expect(() => argumentsParser.parse([...dummyCommandAndRequiredArgs, '--dir-letter-limit', '1'])).toThrow(/dependent|implication/i);

test/modules/candidatePostProcessor.test.ts

@@ -169,6 +169,7 @@ describe('dirLetterLimit', () => {
       commands: ['copy'],
       output: 'Output',
       dirLetter: true,
+      dirLetterCount: 1,
       dirLetterLimit: limit,
       dirGameSubdir: GameSubdirMode[GameSubdirMode.MULTIPLE].toLowerCase(),
     });

test/outputFactory.test.ts

@@ -889,11 +889,26 @@ describe('should respect "--dir-dat-description"', () => {
 describe('should respect "--dir-letter"', () => {
   describe('games with one ROM', () => {
     test.each([
-      ['', os.devNull],
-      ['file.rom', path.join(os.devNull, 'F', 'file.rom')],
-      ['🙂.rom', path.join(os.devNull, '#', '🙂.rom')],
-    ])('option is true: %s', async (romName, expectedPath) => {
-      const options = new Options({ commands: ['copy'], output: os.devNull, dirLetter: true });
+      [0, '', os.devNull],
+      [1, '', os.devNull],
+      [2, '', os.devNull],
+      [999, '', os.devNull],
+      [1, 'file.rom', path.join(os.devNull, 'F', 'file.rom')],
+      [3, 'file.rom', path.join(os.devNull, 'FIL', 'file.rom')],
+      [10, 'file.rom', path.join(os.devNull, 'FILEAAAAAA', 'file.rom')],
+      [1, '007.rom', path.join(os.devNull, '#', '007.rom')],
+      [2, '007.rom', path.join(os.devNull, '##', '007.rom')],
+      [10, '007.rom', path.join(os.devNull, '###AAAAAAA', '007.rom')],
+      [1, '🙂.rom', path.join(os.devNull, '#', '🙂.rom')],
+      [3, '🙂.rom', path.join(os.devNull, '##A', '🙂.rom')],
+      [10, '🙂.rom', path.join(os.devNull, '##AAAAAAAA', '🙂.rom')],
+    ])('option is true: %s', async (dirLetterCount, romName, expectedPath) => {
+      const options = new Options({
+        commands: ['copy'],
+        output: os.devNull,
+        dirLetter: true,
+        dirLetterCount,
+      });
       const rom = new ROM({ name: romName, size: 0, crc: '' });
 
       const outputPath = OutputFactory.getPath(
@@ -939,6 +954,7 @@ describe('should respect "--dir-letter"', () => {
         commands: ['copy'],
         output: os.devNull,
         dirLetter: true,
+        dirLetterCount: 1,
         dirGameSubdir: GameSubdirMode[GameSubdirMode.MULTIPLE].toLowerCase(),
       });