packages/babel-plugin-syntax-typescript/src/index.js
import { declare } from "@babel/helper-plugin-utils";
function removePlugin(plugins, name) {
const indices = [];
plugins.forEach((plugin, i) => {
const n = Array.isArray(plugin) ? plugin[0] : plugin;
if (n === name) {
indices.unshift(i);
}
});
for (const i of indices) {
plugins.splice(i, 1);
}
}
export default declare((api, { isTSX }) => {
api.assertVersion(7);
return {
name: "syntax-typescript",
manipulateOptions(opts, parserOpts) {
const { plugins } = parserOpts;
// If the Flow syntax plugin already ran, remove it since Typescript
// takes priority.
removePlugin(plugins, "flow");
// If the JSX syntax plugin already ran, remove it because JSX handling
// in TS depends on the extensions, and is purely dependent on 'isTSX'.
removePlugin(plugins, "jsx");
parserOpts.plugins.push(
"typescript",
"classProperties",
// TODO: This is enabled by default now, remove in Babel 8
"objectRestSpread",
);
if (isTSX) {
parserOpts.plugins.push("jsx");
}
},
};
});