We have some code that uses ast-query, and it has started choking on some newer ES2015 features. The current error we get is this:
Error: Unknown node type Super.
at Controller.traverse (my-project/node_modules/estraverse/estraverse.js:518:31)
at traverse (my-project/node_modules/estraverse/estraverse.js:710:27)
at Object.attachComments (my-project/node_modules/estraverse/estraverse.js:799:9)
at new Tree (my-project/node_modules/ast-query/lib/tree.js:33:25)
at module.exports (my-project/node_modules/ast-query/lib/tree.js:115:10)
....

After digging in, it appears that escodegen-wallaby has an outdated dependency on estraverse (1.9.x), which causes it to fail to parse certain newer code. estraverse has been updated with the fixes (4.x), but escodegen-wallaby has not been updated to use it. There is already an open issue on the upstream escodegen repo to update the estraverse dependency.

Just FYI. Feel free to close since the issue is really with escodegen-wallaby.

const str = 'import Vue from 'vue'; .... export default xxx;';
when i use: program(str);
throw err: SyntaxError: 'import' and 'export' may appear only with 'sourceType: module'

Like this: function.for.for.for.append()

How would I do that?

Version 1.6.13 of escodegen-wallaby was just published.

This version is covered by your current version range and after updating it in your project the build failed.

escodegen-wallaby is a direct dependency of this project, and it is very likely causing it to break. If other packages depend on yours, this update is probably also breaking those in turn.

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And if a value is later provided.

Version 4.1.0 of acorn-jsx was just published.

This version is covered by your current version range and after updating it in your project the build failed.

acorn-jsx is a direct dependency of this project, and it is very likely causing it to break. If other packages depend on yours, this update is probably also breaking those in turn.

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Hi there,

I'm trying to parse an export default statement in order to append something to an array. Ideally I'd like the following to work:

program = require('ast-query');
tree = program('export default [];', {}, { sourceType: 'module' });
console.log(tree.push('item').toString());

However I get the following when trying to parse the program:

When trying to update a config block that was a variable reference, an error was being thrown:

var conf = {
  abc: bar
};

/Users/eddie/Dropbox/Sites/OSS/yeoman/generator/node_modules/gruntfile-editor/index.js:33
    .key(name).value(config);
               ^
TypeError: Object #<Object> has no method 'value'
    at GruntfileEditor.insertConfig (/Users/eddie/Dropbox/Sites/OSS/yeoman/generator/node_modules/gruntfile-editor/index.js:33:16)
    at module.exports (/Users/eddie/Dropbox/Sites/OSS/yeoman/generator-angular/helpers/gruntfile.js:16:18)
    at module.exports.yeoman.generators.Base.extend.writing.build (/Users/eddie/Dropbox/Sites/OSS/yeoman/generator-angular/generators/app/index.js:255:17)
    at /Users/eddie/Dropbox/Sites/OSS/yeoman/generator/lib/base.js:387:14
    at processImmediate [as _immediateCallback] (timers.js:336:15)

I am trying to edit a file that has a block like this

const reducers = combineReducers({
    app,
    home
});

I have been able to add a new key to it using this command:

tree.callExpression('combineReducers').arguments.at(0).key('test').value('test')

This ends up creating code like this:

const reducers = combineReducers({
    app,
    home,
    test: test
});

How can I get it to result in this??:

const reducers = combineReducers({
    app,
    home,
    test
});

The current code isn't great. It abstract recursing over a tree and making modifications based on strings.

This make for some pretty complicated code logic, and managing the white space/commas is not ideal (currently RegExp based).

From this experience, I plan to rewrite this module completely.

The way I view it, AST-Query should work directly on the tree object by appending and searching nodes. This mean modifications will be instantaneous (no need to process the tree after each modifications) and will hopefully make the code simpler and more reliable.

A main goal is adding capacity to inject new nodes in the three. Currently it is easy to modify an existing node, but not injecting one.

I wanted to do some manipulation and I couldn't find a way to insert a property into an ObjectExpression. I dug around and found the value factory (/lib/factory/value.js) that allows to easily create AST elements.

However I couldn't find a way to create an object property, is that supported somehow?

Would be nice to have access to the value factory and be able to create object properties through it.

EDIT: this seems to work:

/**
 * Create a property node from a value string
 * @param  {String} valKey key string
 * @param  {String} valStr value string
 * @return {Object}        Property node
 */
exports.createProp = function (valKey, valStr) {
  var tree = esprima.parse('var astValFactory = { ' + valKey + ': ' + valStr + '};',esprimaOptions);
  tree = escodegen.attachComments(tree, tree.comments, tree.tokens);
  return tree.body[0].declarations[0].init.properties[0];
};

Thanks!

It's faster, more actively maintained and got ES6 support.

https://github.com/marijnh/acorn

Version 1.0.2 of grunt was just published.

This version is covered by your current version range and after updating it in your project the build failed.

grunt is a devDependency of this project. It might not break your production code or affect downstream projects, but probably breaks your build or test tools, which may prevent deploying or publishing.

Your Greenkeeper Bot 🌴

Maybe I'm missing something fundamental here, but it seems the API is very limited with regards to tree manipulation (or the documentation is lacking). E.g. I'd want to replace the arguments of a CallExpression, but the ArrayExpression node only provides methods to add nodes, not remove them. Obviously I can start hacking away and start doing stuff like methodCall.arguments.nodes[0].pop(), but that's verrrry yucky.

Am I missing the point of your lib, or is this planned, or did I just somehow miss this?

Hi,

I found a bug while writing a yeoman generator. The sort function in body.prepend is not correct in all cases. You can see this jsfiddle that demonstrate the problem: http://jsfiddle.net/j5xynq0k/.

I can think of two options to correct this:

1. Correcting the sort function

Body.prototype.prepend = function (code) {
  var values = esprima.parse(code).body;
  Array.prototype.unshift.apply(this.node, values);

  // Ensure "use strict" declaration is kept on top
  this.node.sort(function (prev, node) {
    if (node && node.expression && node.expression.type === 'Literal' && node.expression.value === 'use strict') {
      return 1;
    } else if (prev && prev.expression && prev.expression.type === 'Literal' && prev.expression.value === 'use strict') {
        return -1;
    } else {
        return 0;
    }
  });

  return this;
};

2. Getting rid of the sort as "use strict" statement will always be first. This also allow to keep statement in order (whereas sort is not stable).

Body.prototype.prepend = function (code) {
  var values = esprima.parse(code).body;
  var insertionIndex = 0;
  var nodes = this.node;

  // Ensure "use strict" declaration is kept on top
  if (nodes[0] && nodes[0].expression && nodes[0].expression.type === 'Literal' && nodes[0].expression.value === 'use strict') {
    insertionIndex = 1;
  }

  values.forEach(function (value){
    nodes.splice(insertionIndex, 0, value);
  });

  return this;
};

I'd rather go for 2) as it keep statements order.

Thanks for your work on this very useful api !

I am trying to query the remove properties in this data object and then remove them.
Does AST-query allow more generic queries like (just an example)
module.exports = Object(\.+\g, Array(Object(remove)))

module.exports = {
  form0: [
    {
      remain: "remain val",
      remove: "remove val",
    },
    {
      remove: "remove val",
      remain: "remain val",
    },
  ],
  form1: [
    {
      remain2: "remain2 val",
      remain1: "remain1 val",
    }
  ],
}

Result once all remove keys are removed

module.exports = {
  form0: [
    {
      remain: "remain val",
    },
    {
      remain: "remain val",
    },
  ],
  form1: [{
    remain2: "remain2 val",
    remain1: "remain1 val",
  }],
}

esprima.parse('import foo from "bar"');

The online parser demo at http://esprima.org/demo/parse.html also gives this error.

You need to specify that it is a module that is being parsed (vs a script):

esprima.parse('import foo from "bar"', { sourceType: 'module'} );

using ast-query, we are currently unable to pass options to parse.

will fork and make sure value flows to base esprima provider.

Version 4.17.5 of lodash was just published.

This version is covered by your current version range and after updating it in your project the build failed.

lodash is a direct dependency of this project, and it is very likely causing it to break. If other packages depend on yours, this update is probably also breaking those in turn.

Your Greenkeeper Bot 🌴

I'd love to tell someone what something is where their cursor is. Is it possible to query by "range"? For example, I could pass tree.atPosition(48) and it would return

Node {
       type: 'CallExpression',
       start: 47,
       end: 62,
       range: [Object],
       callee: [Object],
       arguments: [Object] }

A value() method for arrays would be nice, like ObjectExpression.value().
I'm working on a pull request now but might have a few questions.

Also, adding ArrayExpression tests.

Implement something like https://github.com/marcello3d/node-tosource so actual objects can be used instead of just strings.

Are we able to get append/prepend API for inserting calls in function bodies? Currently the append/prepend API only works for the tree body.

Example:

function test() {
    foo('test');
}

Fails: c.body.node[0].body.append('bar();').

So I looked for workarounds. I tried to manually push this new call into the body array via c.body.node[0].body.body.push('bar();'). But doing so fails because bar(); is a string and not an esprima object. A possible solution is to expose AST-query nodes modules so we can do the above. Or add documentation that the body array requires an esprima object.

I can code this change, just need vision.

Any way to get this to use acorn 5 so the "range" property is included?

Version 10 of Node.js (code name Dubnium) has been released! 🎊

To see what happens to your code in Node.js 10, Greenkeeper has created a branch with the following changes:

• Added the new Node.js version to your .travis.yml

If you’re interested in upgrading this repo to Node.js 10, you can open a PR with these changes. Please note that this issue is just intended as a friendly reminder and the PR as a possible starting point for getting your code running on Node.js 10.

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