feat: rename single file on copy (#18)

* feat: rename single file on copy

Author: ghiscoding

README.md

@@ -105,6 +105,23 @@ Other options include
 - `-a` or `--all` which includes files that start with a dot.
 - `-F` or `--follow` which follows symbolic links
 
+### Copy and Rename a Single File
+
+You can copy and rename a single file by specifying the source file and the destination filename (not just a directory). For example, to copy `input/.env_publish` to `output/.env`:
+
+```bash
+copyfiles input/.env_publish output/.env
+```
+
+This will copy and rename the file in one step.  
+You can use this for any filename, not just files starting with a dot:
+
+```bash
+copyfiles input/original.txt output/renamed.txt
+```
+
+If the destination path is a directory, the file will be copied into that directory as usual. If the destination path is a filename, the file will be copied and renamed.
+
 ### JavaScript API
 
 ```js

src/__tests__/cli.spec.ts

@@ -1,4 +1,4 @@
-import { readdir, rmSync, writeFileSync } from 'node:fs';
+import { existsSync, readdir, rmSync, writeFileSync } from 'node:fs';
 import { afterAll, afterEach, beforeEach, describe, expect, test, vi } from 'vitest';
 
 import { createDir } from '../index';
@@ -42,28 +42,43 @@ describe('copyfiles', () => {
     // Mock process.exit so it doesn't kill the test runner
     // @ts-ignore
     const exitSpy = vi.spyOn(process, 'exit').mockImplementation((code?: string | number | null | undefined) => {
-      // Do nothing
+      if (code && code !== 0) {
+        exitSpy.mockRestore();
+        done(new Error(`process.exit called with code ${code}`));
+      }
+      // Do nothing for code 0
     });
 
     import('../cli')
       .then(() => {
-        // Wait a tick to ensure file writes are complete
-        setTimeout(() => {
+        // Wait until output2/input2 exists, then check files
+        const start = Date.now();
+        const check = () => {
+          if (!existsSync('output2/input2')) {
+            if (Date.now() - start > 55) {
+              exitSpy.mockRestore();
+              return done(new Error('Timeout: output2/input2 was not created'));
+            }
+            setTimeout(check, 50);
+            return;
+          }
           readdir('output2/input2', (err, files) => {
-            expect(files).toEqual(['a.txt', 'b.txt']);
-            exitSpy.mockRestore();
-            done();
+            try {
+              expect(err).toBeNull();
+              expect(files).toEqual(['a.txt', 'b.txt']);
+              exitSpy.mockRestore();
+              done();
+            } catch (e) {
+              exitSpy.mockRestore();
+              done(e);
+            }
           });
-        }, 100); // 100ms delay to allow async file writes
+        };
+        check();
       })
       .catch(e => {
-        setTimeout(() => {
-          readdir('output2/input2', (err, files) => {
-            expect(files).toEqual(['a.txt', 'b.txt']);
-            exitSpy.mockRestore();
-            done();
-          });
-        }, 100);
+        exitSpy.mockRestore();
+        done(e);
       });
-  }))
+  }), 300);
 })

src/__tests__/index.spec.ts

@@ -317,4 +317,34 @@ describe('copyfiles', () => {
       });
     });
   }));
+
+  test('copies and renames a single file when destination is a file path', () => new Promise((done: any) => {
+    writeFileSync('input/.env.production', 'SOME=VALUE');
+    copyfiles(['input/.env.production', 'output/.env'], {}, (err) => {
+      expect(err).toBeUndefined();
+      readdir('output', (err, files) => {
+        expect(files).toContain('.env');
+        // Check file contents
+        const { readFileSync } = require('node:fs');
+        const content = readFileSync('output/.env', 'utf8');
+        expect(content).toBe('SOME=VALUE');
+        done();
+      });
+    });
+  }));
+
+  test('copies and renames a single file to a new filename (no dot)', () => new Promise((done: any) => {
+    writeFileSync('input/original.txt', 'HELLO WORLD');
+    copyfiles(['input/original.txt', 'output/renamed.txt'], {}, (err) => {
+      expect(err).toBeUndefined();
+      readdir('output', (err, files) => {
+        expect(files).toContain('renamed.txt');
+        // Check file contents
+        const { readFileSync } = require('node:fs');
+        const content = readFileSync('output/renamed.txt', 'utf8');
+        expect(content).toBe('HELLO WORLD');
+        done();
+      });
+    });
+  }));
 });

src/index.ts

@@ -58,11 +58,26 @@ export function copyfiles(paths: string[], options: CopyFileOptions, callback?:
 
   // find file source(s) and destination directory
   const sources = paths.slice(0, -1);
-  let outDir = paths.pop() as string;
-  outDir = outDir.startsWith('~') ? untildify(outDir) : outDir;
+  let outPath = paths.pop() as string;
+  outPath = outPath.startsWith('~') ? untildify(outPath) : outPath;
+
+  // Special case: single file to file (rename)
+  const isSingleFile = sources.length === 1 && !sources[0].includes('*');
+  let isDestFile = false;
+  if (isSingleFile) {
+    try {
+      const stat = existsSync(outPath) ? require('node:fs').statSync(outPath) : null;
+      isDestFile = !stat || !stat.isDirectory();
+      /* v8 ignore next 3 */
+    } catch {
+      isDestFile = true;
+    }
+  }
 
-  // create destination directory if not exists
-  createDir(outDir);
+  if (!isDestFile) {
+    // create destination directory if not exists
+    createDir(outPath);
+  }
 
   let globOptions: GlobOptions = {};
   if (Array.isArray(options.exclude) && options.exclude.length > 0) {
@@ -101,22 +116,28 @@ export function copyfiles(paths: string[], options: CopyFileOptions, callback?:
   }
 
   allFiles.forEach((inFile) => {
-    copyFileStream(inFile, outDir, options, (err) => {
-      if (hasError) return;
-      if (err) {
-        hasError = true;
-        if (typeof cb === 'function') cb(err);
-        return;
-      }
-      completed++;
-      if (completed === allFiles.length) {
-        if (options.verbose || options.stat) {
-          console.log(`Files copied:   ${allFiles.length}`);
-          console.timeEnd('Execution time');
+    copyFileStream(
+      inFile,
+      outPath,
+      options,
+      (err) => {
+        if (hasError) return;
+        if (err) {
+          hasError = true;
+          if (typeof cb === 'function') cb(err);
+          return;
         }
-        if (typeof cb === 'function') cb();
-      }
-    });
+        completed++;
+        if (completed === allFiles.length) {
+          if (options.verbose || options.stat) {
+            console.log(`Files copied:   ${allFiles.length}`);
+            console.timeEnd('Execution time');
+          }
+          if (typeof cb === 'function') cb();
+        }
+      },
+      isSingleFile && isDestFile // pass as "rename" mode
+    );
   });
 }
 
@@ -127,13 +148,22 @@ export function copyfiles(paths: string[], options: CopyFileOptions, callback?:
  * @param {CopyFileOptions} options
  * @param {(e?: Error) => void} cb
  */
-function copyFileStream(inFile: string, outDir: string, options: CopyFileOptions, cb: (e?: Error) => void) {
+function copyFileStream(
+  inFile: string,
+  outDir: string,
+  options: CopyFileOptions,
+  cb: (e?: Error) => void,
+  renameMode = false
+) {
   const fileDir = dirname(inFile);
   const fileName = basename(inFile);
   outDir = outDir.startsWith('~') ? untildify(outDir) : outDir;
 
   let dest: string;
-  if (options.flat || options.up === true) {
+  if (renameMode) {
+    dest = outDir;
+    createDir(path.dirname(dest));
+  } else if (options.flat || options.up === true) {
     dest = join(outDir, fileName);
   } else {
     const upCount = options.up || 0;
@@ -166,7 +196,7 @@ function copyFileStream(inFile: string, outDir: string, options: CopyFileOptions
   readStream.on('error', onceCallback);
   writeStream.on('error', onceCallback);
   writeStream.on('close', () => {
-    // Only call callback if not already called by an error
+    // Only execute callback if not already called by an error
     if (!called) {
       onceCallback();
     }