packages/babel-core/src/transformation/file/generate.js
// @flow
import type { PluginPasses } from "../../config";
import convertSourceMap, { typeof SourceMap } from "convert-source-map";
import generate from "@babel/generator";
import type File from "./file";
import mergeSourceMap from "./merge-map";
export default function generateCode(
pluginPasses: PluginPasses,
file: File,
): {
outputCode: string,
outputMap: SourceMap | null,
} {
const { opts, ast, code, inputMap } = file;
const results = [];
for (const plugins of pluginPasses) {
for (const plugin of plugins) {
const { generatorOverride } = plugin;
if (generatorOverride) {
const result = generatorOverride(
ast,
opts.generatorOpts,
code,
generate,
);
if (result !== undefined) results.push(result);
}
}
}
let result;
if (results.length === 0) {
result = generate(ast, opts.generatorOpts, code);
} else if (results.length === 1) {
result = results[0];
if (typeof result.then === "function") {
throw new Error(
`You appear to be using an async codegen plugin, ` +
`which your current version of Babel does not support. ` +
`If you're using a published plugin, ` +
`you may need to upgrade your @babel/core version.`,
);
}
} else {
throw new Error("More than one plugin attempted to override codegen.");
}
let { code: outputCode, map: outputMap } = result;
if (outputMap && inputMap) {
outputMap = mergeSourceMap(inputMap.toObject(), outputMap);
}
if (opts.sourceMaps === "inline" || opts.sourceMaps === "both") {
outputCode += "\n" + convertSourceMap.fromObject(outputMap).toComment();
}
if (opts.sourceMaps === "inline") {
outputMap = null;
}
return { outputCode, outputMap };
}