gen-typescript-declarations
A library which generates TypeScript declarations for Polymer and custom elements.
How do I use the typings?
Polymer 3
Typings for Polymer 3 are included starting from version 3.0.5. To use them,
install @polymer/polymer
from npm, and use standard ES module import
specifiers:
import {PolymerElement} from '@polymer/polymer';
class MyElement extends PolymerElement {
...
}
Polymer 2
Typings for Polymer 2 are included starting from version 2.4.0. To use them,
install Polymer from Bower and add a triple-slash
directive
anywhere in your TypeScript project for the typings you require. Each HTML
import from Polymer has a corresponding typings file. For example, if you depend
on polymer-element.html
:
/// <reference path="./bower_components/polymer/types/polymer-element.d.ts" />`
class MyElement extends Polymer.Element {
...
}
Alternatively, you can add the dependency to tsconfig.json
in the root of your
project:
{
...
"include": [
"src/**/*.ts",
"src/bower_components/polymer/**/*.d.ts",
]
}
You may also be interested in the Polymer decorators.
How do I generate new typings?
You can run this package from the command line with
gen-typescript-declarations
, or as a library with the generateDeclarations
function.
It is recommended to integrate typings generation as part of your build/release process:
$ npm install --save-dev @polymer/gen-typescript-declarations
Add a generate-typings
script to your package.json
:
{
...
"scripts": {
"generate-typings": "gen-typescript-declarations"
}
}
If you're using NPM, you can add this script to the NPM prepack
script to
generate and include typings in your NPM package every time you publish. Most
users will want to configure their .gitignore
so that the generated typings
are not committed to their Git repository. In this case, take care to configure
your .npmignore
and/or package.json
to ensure that they are included when
you publish to NPM (run npm pack
to check before publishing).
If you are still using Bower, ensure you run npm run generate-typings
to
generate the latest typings and commit them to your repository before tagging
each release.
Config options
By default the gen-typescript-declarations
command will read a file called
gen-tsd.json
in your root directory. It has the following options:
-
excludeFiles
: string[]
Skip source files whose paths match any of these glob patterns. If
undefined
, defaults to excluding directories ending in "test" or "demo". -
excludeIdentifiers
: string[]
Do not emit any declarations for features that have any of these identifiers.
-
removeReferences
: string[]
Remove any triple-slash references to these files, specified as paths relative to the analysis root directory.
-
addReferences
: {[filepath: string]: string[]}
Additional files to insert as triple-slash reference statements. Given the map
a: b[]
, a will get an additional reference statement for each file path in b. All paths are relative to the analysis root directory. -
renameTypes
: {[name: string]: string}
Whenever a type with a name in this map is encountered, replace it with the given name. Note this only applies to named types found in places like function/method parameters and return types. It does not currently rename e.g. entire generated classes.
-
autoImport
: {[modulePath: string]: string[]}
A map from an ES module path (relative to the analysis root directory) to an array of identifiers exported by that module. If any of those identifiers are encountered in a generated typings file, an import for that identifier from the specified module will be inserted into the typings file.
Using as a module
You can also use this package as a module:
import {generateDeclarations} from 'gen-typescript-declarations';
const config = {
"exclude": [
"test/**",
],
"removeReferences": [
"../shadycss/apply-shim.d.ts",
],
"addReferences": {
"lib/utils/boot.d.ts": [
"extra-types.d.ts"
]
},
"renameTypes": {
"Polymer_PropertyEffects": "Polymer.PropertyEffects"
}
}
// A map of d.ts file paths to file contents.
const declarations = await generateDeclarations('/my/root/dir', config);
FAQ
Why are some typings missing?
This library is based on Polymer Analyzer which has limitations in its static analysis. For certain patterns, Analyzer relies on additional JSDoc annotations.
Can I augment the generated typings with hand-written ones?
Yes, see the addReferences
config option above.