Node-fs-extra: copy and copySync: reallow copying to subdirectories

[eunakria]

In fs-extra 5.0.0, you fixed an issue that said that directories could be copied to their own subdirectories. This is wonderful, but I couldn't help but notice that it would break some scripts. In some cases, one may want to copy a directory to its subdirectory, and use a filter function to prevent recursion. Perhaps you could give an option which is false by default that allows to copy to a subdirectory?

[RyanZim]

@mcboat What's your real world use-case for copying to a subdirectory?

[eunakria]

In my case, I intended on creating a script which automates the Electron building and packaging process, and to do that without affecting the source I intended on creating a subdirectory in the existing directory.
For example:

• My initial project
  path/to/electron/application |- src/ |- some source files |- a few other files and dirs |- build.js
• After running the copy
  path/to/electron/application |- app/ |- some source files |- src/ |- some source files |- a few other files and dirs |- build.js
• After minifying the files
  path/to/electron/application |- app/ |- some minified files |- src/ |- some source files |- a few other files and dirs |- build.js
  This way, the source files remain untouched while the app is minified and compiled.

[RyanZim]

@manidlou @JPeer264 @jprichardson thoughts here?

[manidlou]

@mcboat I am not sure If I understand your case! Are you copying from src to app? Where are you copying to subdirectory? Will you please give us an example with the code?

[RyanZim]

I'm not understanding the use-case here; closing for the time being.

[duhseekoh]

With v5 this fails and I don't quite follow the logic.

await fs.copy('db', 'build/db');

yields this error: Error: Cannot copy '/db/util' to a subdirectory of itself, '/build/db/util'

I'm copying db to build/db, not to a subdirectory of db (itself).

[RyanZim]

@duhseekoh That's a bug in 5.0.0; should be fixed in 6.0.0

[vjpr]

I saw this again in v8.0. Trying to copy a symlink over another symlink.

[RyanZim]

@vjpr Please open a new issue with a reduced test case.

[brrd]

Can we reopen this issue?

Here is a real world use-case:

const fse = require("fs-extra");

const filter = async (src) => {
    const stat = await fse.lstat(src);
    const dirname = path.basename(src);
    if(stat.isFile() || (stat.isDirectory() && dirname !== "bak")) return true;
};

fse.copy("path/to/directory", "path/to/directory/bak", { filter });

IMO we should not even need a filter to do this. fse.copy() should silently ignore directory/dest/ when trying to copy directory/ contents into directory/dest/, and copy other children files and directories in directory/dest/ as asked.

[RyanZim]

That is a legitimate use-case, albeit a somewhat rare one. Generally, I feel it is better to be explicit than implicit. I do not think we should "silently ignore" certain files.

[brrd]

I do not think we should "silently ignore" certain files.

fs-extra seemed to behave this way in some other situations: remove() ends silently if the file doesn't exist, emptyDir() creates a dir if it does not exist...

For the record, here is my workaround (with glob, because I'm already using it in my project):

const fse = require("fs-extra");
const util = require("util");
const glob = util.promisify(require("glob"));
const path = require("path");

async function copyToSubdir(src, subdirName) {
  const dirs = await glob("*/", { cwd: src, absolute: true, ignore: subdirName });
  const proms = dirs.map((file) => {
    const basename = path.basename(file);
    const dest = path.join(src, subdirName, basename);
    return fse.copy(file, dest);
  });
  return Promise.all(proms);
}