deno2node/lib/deno2node.js

`tsc` replacement for transpiling Deno libraries to run on Node.js.

// based on https://github.com/dsherret/code-block-writer/blob/99454249cd13bd89befa45ac815b37b3e02896f5/scripts/build_npm.ts
import { Node } from "./deps.node.js";
import { transpileSpecifier } from "./_transformations/specifiers.js";
import { vendorEverything } from "./_transformations/vendor.js";
import { shimEverything } from "./_transformations/shim.js";
function transpileImportSpecifiers(sourceFile) {
    for (const statement of sourceFile.getStatements()) {
        if (Node.isImportDeclaration(statement) ||
            Node.isExportDeclaration(statement)) {
            const modSpecifierValue = statement.getModuleSpecifierValue();
            if (modSpecifierValue !== undefined) {
                statement.setModuleSpecifier(transpileSpecifier(modSpecifierValue));
            }
        }
    }
}
const isDenoSpecific = (sourceFile) => sourceFile.getBaseNameWithoutExtension().toLowerCase().endsWith(".deno");
/**
 * Attempts to transform arbitrary `ctx.project` into a valid Node.js project:
 *
 * 1. Changes import specifiers to be Node-friendly:
 *    - changes extension in relative specifiers to `.js`,
 *    - replaces some `https://` imports with bare specifiers.
 *
 * 2. Changes `*.deno.js` imports specifiers to `*.node.js`
 *    (`import './deps.deno.ts'` -> `import './deps.node.js'`).
 *    This can be used for re-exporting dependencies
 *    and other runtime-specific code.
 *
 * 3. Rewrites remaining https: imports to point
 *    into `vendorDir`, if specified:
 *    ```json
 *    // @filename: tsconfig.json
 *    {
 *      "deno2node": {
 *        "vendorDir": "src/.deno2node/vendor/"
 *      }
 *    }
 *    ```
 *
 * 4. Imports Node.js shims for Deno globals
 *    from [shim file], if specified:
 *    ```json
 *    // @filename: tsconfig.json
 *    {
 *      "deno2node": {
 *        "shim": "src/shim.node.ts"
 *      }
 *    }
 *    ```
 *
 * [shim file]: https://github.com/wojpawlik/deno2node/blob/main/src/shim.node.ts
 */
export async function deno2node(ctx) {
    console.time("Basic transformations");
    for (const sourceFile of ctx.project.getSourceFiles()) {
        if (isDenoSpecific(sourceFile)) {
            ctx.project.removeSourceFile(sourceFile);
            continue;
        }
        transpileImportSpecifiers(sourceFile);
    }
    console.timeEnd("Basic transformations");
    await vendorEverything(ctx);
    shimEverything(ctx);
}