ember-template-lint
ember-template-recast
With ember-template-recast, transform a template's AST and reprint it. Its formatting will be preserved.
For instance, it is possible to change a component's property while preserving its formatting:
const recast = require('ember-template-recast');
const template = `
<Sidebar
foo="bar"
item={{hmmm}}
/>
`;
// parse
let ast = recast.parse(template);
// transform
ast.body[1].attributes[1].value.path = builders.path('this.hmmm');
// print
let ouput = recast.print(ast);
output === `
<Sidebar
foo="bar"
item={{this.hmmm}}
/>
`; // is true!Command Line Usage
ember-template-recast comes with a binary for running a transform across multiple files, similar to jscodeshift.
npx ember-template-recast directory/of/templates -t transform.jsExample transform plugin:
module.exports = (env) => {
let { builders: b } = env.syntax;
return {
MustacheStatement() {
return b.mustache(b.path('wat-wat'));
},
};
};APIs
parse
Used to parse a given template string into an AST. Generally speaking, this AST
can be mutated and passed into print (docs below).
const templateRecast = require('ember-template-recast');
const template = `
{{foo-bar
baz="stuff"
}}
`;
let ast = templateRecast.parse(template);
// now you can work with `ast`Used to generate a new template string representing the provided AST.
const templateRecast = require('ember-template-recast');
const template = `
{{foo-bar
baz="stuff"
}}
`;
let ast = templateRecast.parse(template);
ast.body[0].hash[0].key = 'derp';
templateRecast.print(ast);
{{foo-bar
derp="stuff"
}}transform
Used to easily traverse (and possibly mutate) a given template. Returns the resulting AST and the printed template.
The plugin argument has roughly the following interface:
export interface Syntax {
parse: typeof preprocess;
builders: typeof builders;
print: typeof print;
traverse: typeof traverse;
Walker: typeof Walker;
}
export interface TransformPluginEnv {
syntax: Syntax;
contents: string;
filePath?: string;
parseOptions: {
srcName?: string;
};
}
export interface TransformPluginBuilder {
(env: TransformPluginEnv): NodeVisitor;
}The list of known builders on the env.syntax.builders are found
here,
although there are a few small extensions related to formatting
in custom-nodes.ts
Example:
const { transform } = require('ember-template-recast');
const template = `
{{foo-bar
baz="stuff"
}}
`;
let { code } = transform({
template,
plugin(env) {
let { builders: b } = env.syntax;
return {
MustacheStatement() {
return b.mustache(b.path('wat-wat'));
},
};
}
});
console.log(code); // => {{wat-wat}}SemVer Policy
Due to usage of TypeScript and bundling external APIs this project has somewhat unique SemVer commitments. A high level summary is:
Major Version
The following are scenarios that would cause a major version (aka breaking change) release:
- Dropping support for Node versions (e.g. dropping Node 12 support)
- Non-additive changes to the underlying AST (which we bundle from
@glimmer/syntax) - Breaking changes to the
@glimmer/syntaxbuilder APIs
Minor Version
The following are scenarios that would cause a minor version (aka new feature) release:
- Changes to TypeScript version used internally by
ember-template-recast - Changes to make the types used by
ember-template-recastto be more accurate (e.g. narrowing / broadening of previously published types). - Adding new features
Patch Version
The following are scenarios that would cause a patch release:
- Bug fixes to internal re-writing logic
- Bug fix releases of
@glimmer/syntax
License
This project is distributed under the MIT license, see LICENSE for details.