Better support for file path wildcards

[avocadowastaken]

Lets say we have this structure

• src
  • foo
    • bar
  • baz

Using macOS 10.12.2 and node v7.4.0 - this command prettier --write src/**/*.js will ignore content inside of bar directory.

After some research I found that process.argv works like that and there are no workaround. (At least I didn't find any).

And I made my own tool using glob and it worked how I expected.

const fs = require('fs');
const glob = require('glob');
const prettier = require('prettier');
const minimist = require('minimist');

const argv = minimist(process.argv.slice(2));

const files = argv._.length ? argv._ : glob.sync('+(src|test)/**/*.js');

files.forEach((filePath) => {
  fs.readFile(filePath, 'utf8', (readError, source) => {
    console.log(filePath)

    if (readError) {
      console.error(readError);
    } else {
      try {
        const result = prettier.format(source);

        fs.writeFile(filePath, result, (writeError) => {
          if (writeError) {
            console.error(writeError);
          }
        });
      } catch (formatError) {
        console.error(formatError);
      }
    }
  });
});

I know that prettier will Resist adding configuration (#40)
And idea about .prettierrc was already declined (#154)

But what about adding .prettierrc to add current available options only ?

{
  "source": [
    "src/**/*.js",
    "test/**/*.js"
  ],
  "parser": "babylon"
}

Or add --source=src/**/*.js parameter to define which files should be prettified.

And use tools like glob to list all available files from source wildcards.

I will be happy to add PR if you're agree with this proposal.

[lydell]

Regarding globs – it all depends on what your shell supports. In particular, if it supports the ** glob or not.

If a shell supports * but not **, what happens is that you've simply put two *s after each other, which matches exactly the same things as a single *. ("Match zero or more of anything, followed by zero or more of anything (except /s)".)

In bash, you must make sure to enable the "globstar" option (and make sure to run a version of bash that has that option).

# Here's my bash version, which I know has the "globstar" option.
$ bash --version
GNU bash, version 4.3.46(1)-release (x86_64-pc-linux-gnu)
Copyright (C) 2013 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>

This is free software; you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

# Enter bash (just to show that I'm not using some other shell).
$ bash

# Make sure that the "globstar" option is disabled.
$ shopt -u globstar

# Try a `**` glob.
$ echo src/**/*.js
src/baz/baz.js src/foo/foo.js

# Enable the "globstar" option.
$ shopt -s globstar

# Try a `**` glob again. Note how src/foo/bar/bar.js and src/src.js are found now.
$ echo src/**/*.js
src/baz/baz.js src/foo/bar/bar.js src/foo/foo.js src/src.js

# As far as I know, the "sh" shell does not support the `**` glob (at least not
# by default on my system):
$ sh
$ echo src/**/*.js
src/baz/baz.js src/foo/foo.js
$ echo src/*/*.js
src/baz/baz.js src/foo/foo.js

Since there are so many shells and so many versions, it's difficult to get globbing right. To make things worse, the default shell in many operating system doesn't support the ** glob (by default). This is especially a problem in npm scripts:

{
  "scripts": {
    "prettier": "prettier src/**/*.js"
  }
}

The above is not a good cross-platform solution. Therefore, it is common among Node.js CLI tools to incorprate their own globbing support, allowing to write the above example as:

{
  "scripts": {
    "prettier": "prettier 'src/**/*.js'"
  }
}

Note the added single quotes above. They make sure that the shell does not try to expand the globs. Instead, the exact string src/**/*.js will be sent to prettier (as process.argv[2]). Then, prettier can pass that string to some glob library, such as glob, and let it expand the glob in a consistent way. I think this would be a nice improvement to the prettier CLI.

[vjeux]

I think we should change the README to avoid using the glob expansion since it doesn't work in bash. We can replace it find find src -name '*.js' | xargs prettier but this doesn't feel super nice for people that don't know bash that well and doesn't work on windows.

I agree that passing globs as strings and having prettier handle them seem like a great solution.

[metacoding]

Thanks for your explanations but none of the above patterns works in Windows. Can you give me a hint what should I do to introduce all js files in src directory to prettier?

[hawkrives]

@metacoding If you wrap your pattern in quotes, Prettier will execute the pattern for you in a cross-platform way.

prettier "src/**/*.js" will rub prettier on every file within a "src/" folder, for instance.

I believe there is some information in the docs about this, but I'm not sure where it is at the moment. (apologies).