ast-grep

Like grep, but more powerful than you can possibly imagine.

Search your JavaScript files for patterns based on AST shape, rather than substrings or regular expressions.

Install

With yarn:

yarn global add ast-grep

With npm:

npm install --global ast-grep

Usage

$ ast-grep --help
Options:
  --anonymous, -a  Ignore all names in the AST                         [boolean]
  --file, -f       Load pattern from a file                             [string]
  --help           Show help                                           [boolean]
  --version        Show version number                                 [boolean]

Examples:
  ast-grep -a 'fn()' file.js           Find all no-arg function calls in
                                       'file.js'.
  ast-grep -f pattern.js '**/*.js'     Match the pattern in 'pattern.js' across
                                       all JS files.
  echo 'foo' | ast-grep 'pattern'      Match 'pattern' on standard input.

On standard in:

$ echo 'code();' | ast-grep 'code'
code();
$ ast-grep 'foo()' < file.js
foo();

On a set of files:

$ ast-grep 'yield* foo();' '**/*.js'

FAQ

Q. But @azz, grep stands for Global Regular Expression Print, this tool doesn't use Regular Expressions!

A. I know, but gastp doesn't sound great.