Resolve component URLs during compilation (#40)

Previously dynamic component URLs were being resolved client-side in a weird way that only worked during dev. This change makes them handle during compilation, so it works in both (and improves readability of the dynamic import output).

snowpack-plugin.cjs

@@ -3,7 +3,7 @@ const { readFile } = require('fs').promises;
 // Snowpack plugins must be CommonJS :(
 const transformPromise = import('./lib/compiler/index.js');
 
-module.exports = function (snowpackConfig, { resolve, extensions } = {}) {
+module.exports = function (snowpackConfig, { resolve, extensions, astroConfig } = {}) {
   return {
     name: 'snowpack-astro',
     knownEntrypoints: ['deepmerge'],
@@ -16,6 +16,7 @@ module.exports = function (snowpackConfig, { resolve, extensions } = {}) {
       const projectRoot = snowpackConfig.root;
       const contents = await readFile(filePath, 'utf-8');
       const compileOptions = {
+        astroConfig,
         resolve,
         extensions,
       };

src/@types/compiler.ts

@@ -1,8 +1,9 @@
 import type { LogOptions } from '../logger';
-import type { ValidExtensionPlugins } from './astro';
+import type { AstroConfig, ValidExtensionPlugins } from './astro';
 
 export interface CompileOptions {
   logging: LogOptions;
   resolve: (p: string) => Promise<string>;
+  astroConfig: AstroConfig;
   extensions?: Record<string, ValidExtensionPlugins>;
 }

src/compiler/codegen.ts

@@ -1,5 +1,5 @@
 import type { CompileOptions } from '../@types/compiler';
-import type { ValidExtensionPlugins } from '../@types/astro';
+import type { AstroConfig, ValidExtensionPlugins } from '../@types/astro';
 import type { Ast, TemplateNode } from '../parser/interfaces';
 import type { JsxItem, TransformResult } from '../@types/astro';
 
@@ -111,14 +111,25 @@ const defaultExtensions: Readonly<Record<string, ValidExtensionPlugins>> = {
 
 type DynamicImportMap = Map<'vue' | 'react' | 'react-dom' | 'preact', string>;
 
-function getComponentWrapper(_name: string, { type, plugin, url }: ComponentInfo, dynamicImports: DynamicImportMap) {
+interface GetComponentWrapperOptions {
+  filename: string;
+  astroConfig: AstroConfig;
+  dynamicImports: DynamicImportMap;
+}
+function getComponentWrapper(_name: string, { type, plugin, url }: ComponentInfo, opts: GetComponentWrapperOptions) {
+  const { astroConfig, dynamicImports, filename } = opts;
+  const { astroRoot } = astroConfig;
   const [name, kind] = _name.split(':');
+  const currFileUrl = new URL(`file://${filename}`);
 
   if (!plugin) {
     throw new Error(`No supported plugin found for extension ${type}`);
   }
 
-  const getComponentUrl = (ext = '.js') => `new URL(${JSON.stringify(url.replace(/\.[^.]+$/, ext))}, \`http://TEST\${import.meta.url\}\`).pathname.replace(/^\\/\\//, '/_astro/')`;
+  const getComponentUrl = (ext = '.js') => {
+    const outUrl = new URL(url, currFileUrl);
+    return '/_astro/' + path.posix.relative(astroRoot.pathname, outUrl.pathname).replace(/\.[^.]+$/, ext);
+  };
 
   switch (plugin) {
     case 'astro': {
@@ -242,8 +253,8 @@ async function acquireDynamicComponentImports(plugins: Set<ValidExtensionPlugins
   return importMap;
 }
 
-export async function codegen(ast: Ast, { compileOptions }: CodeGenOptions): Promise<TransformResult> {
-  const { extensions = defaultExtensions } = compileOptions;
+export async function codegen(ast: Ast, { compileOptions, filename }: CodeGenOptions): Promise<TransformResult> {
+  const { extensions = defaultExtensions, astroConfig } = compileOptions;
   await eslexer.init;
 
   const componentImports: ImportDeclaration[] = [];
@@ -343,7 +354,7 @@ export async function codegen(ast: Ast, { compileOptions }: CodeGenOptions): Pro
             if (!components[componentName]) {
               throw new Error(`Unknown Component: ${componentName}`);
             }
-            const { wrapper, wrapperImport } = getComponentWrapper(name, components[componentName], dynamicImports);
+            const { wrapper, wrapperImport } = getComponentWrapper(name, components[componentName], {astroConfig, dynamicImports, filename});
             if (wrapperImport) {
               importExportStatements.add(wrapperImport);
             }
@@ -395,7 +406,7 @@ export async function codegen(ast: Ast, { compileOptions }: CodeGenOptions): Pro
           if (!componentImportData) {
             throw new Error(`Unknown Component: ${componentName}`);
           }
-          const { wrapper, wrapperImport } = getComponentWrapper(name, components[componentName], dynamicImports);
+          const { wrapper, wrapperImport } = getComponentWrapper(name, components[componentName], {astroConfig, dynamicImports, filename});
           if (wrapperImport) {
             importExportStatements.add(wrapperImport);
           }

src/compiler/index.ts

@@ -1,4 +1,5 @@
 import type { LogOptions } from '../logger.js';
+import type { AstroConfig } from '../@types/astro';
 
 import path from 'path';
 import micromark from 'micromark';
@@ -14,15 +15,11 @@ import { optimize } from './optimize/index.js';
 import { codegen } from './codegen.js';
 
 interface CompileOptions {
+  astroConfig: AstroConfig;
   logging: LogOptions;
   resolve: (p: string) => Promise<string>;
 }
 
-const defaultCompileOptions: CompileOptions = {
-  logging: defaultLogOptions,
-  resolve: (p: string) => Promise.resolve(p),
-};
-
 function internalImport(internalPath: string) {
   return `/_astro_internal/${internalPath}`;
 }
@@ -107,7 +104,7 @@ async function transformFromSource(
 
 export async function compileComponent(
   source: string,
-  { compileOptions = defaultCompileOptions, filename, projectRoot }: { compileOptions: CompileOptions; filename: string; projectRoot: string }
+  { compileOptions, filename, projectRoot }: { compileOptions: CompileOptions; filename: string; projectRoot: string }
 ): Promise<CompileResult> {
   const sourceJsx = await transformFromSource(source, { compileOptions, filename, projectRoot });
   const isPage = path.extname(filename) === '.md' || sourceJsx.items.some((item) => item.name === 'html');

src/frontend/render/renderer.ts

@@ -23,7 +23,7 @@ export function createRenderer(renderer: Renderer) {
         return [...acc, `import("${context.frameworkUrls[lib as any]}")`];
       }, [])
       .join(',');
-    return `const [{${context.componentExport}: Component}, ${values}] = await Promise.all([import(${context.componentUrl})${renderer.imports ? ', ' + libs : ''}]);`;
+    return `const [{${context.componentExport}: Component}, ${values}] = await Promise.all([import("${context.componentUrl}")${renderer.imports ? ', ' + libs : ''}]);`;
   };
   const serializeProps = (props: Record<string, any>) => JSON.stringify(props);
   const createContext = () => {

src/runtime.ts

@@ -126,7 +126,9 @@ export async function createRuntime(astroConfig: AstroConfig, { logging }: Runti
   const astroPlugOptions: {
     resolve?: (s: string) => Promise<string>;
     extensions?: Record<string, string>;
+    astroConfig: AstroConfig;
   } = {
+    astroConfig,
     extensions,
     resolve: async (pkgName: string) => snowpack.getUrlForPackage(pkgName),
   };