Pass through snowpack log colors and show stats during production bui…

…lds (#56)

* Pass through snowpack log colors to stdio

* Upgrade snowpack and show stats during production builds

* Always exit if initial build fails, even in dev mode

* Upgrade to snowpack v1.5.1

package.json

@@ -24,7 +24,7 @@
     "p-limit": "^2.2.2",
     "rimraf": "^3.0.2",
     "servor": "^3.1.0",
-    "snowpack": "1.4.0",
+    "snowpack": "1.5.1",
     "terser": "^4.6.3"
   },
   "devDependencies": {

src/index.ts

@@ -1,6 +1,5 @@
 /* eslint-disable no-console */
-import * as util from 'util';
-import { exec as execSync } from 'child_process';
+import { spawn } from 'child_process';
 import { promises as fs, existsSync } from 'fs';
 import * as path from 'path';
 import * as svelte from 'svelte/compiler';
@@ -14,7 +13,6 @@ import servor from 'servor';
 import rimraf from 'rimraf';
 import { init as initEsModuleLexer, parse } from 'es-module-lexer';
 import throttle from 'lodash.throttle';
-const exec = util.promisify(execSync);
 
 const IS_PRODUCTION_MODE = process.env.NODE_ENV === 'production';
 const BABEL_CONFIG = loadBabelConfig();
@@ -170,7 +168,7 @@ async function transform(
                     await snowpack(destPath);
                 } catch (err) {
                     console.error('\n\nFailed to build with snowpack');
-                    console.error(err.stderr || err);
+                    err && console.error(err.stderr || err);
                     // Don't continue building...
                     return;
                 }
@@ -238,22 +236,38 @@ async function checkForNewWebModules(
 // in dev mode, snowpack will be ran again.
 async function snowpack(includeFiles: string): Promise<void> {
     const maybeOptimize = IS_PRODUCTION_MODE ? '--optimize' : '';
+    const maybeStats = IS_PRODUCTION_MODE ? '--stat' : '';
 
-    console.info(`\nBuilding web_modules with snowpack...`);
+    console.info(`\n\nBuilding web_modules with snowpack...`);
 
     const snowpackLocation = path.resolve(
         require.resolve('snowpack'),
         '../index.bin.js'
     );
 
-    const { stdout, stderr } = await exec(
-        `node ${snowpackLocation} --include '${includeFiles}' --dest dist/web_modules ${maybeOptimize}`
-    );
-
-    // TODO: hide behind --verbose flag
-    // Show any output from snowpack...
-    stdout && console.info(stdout);
-    stderr && console.info(stderr);
+    await new Promise((resolve, reject) => {
+        const proc = spawn(
+            'node',
+            [
+                snowpackLocation,
+                '--include',
+                includeFiles,
+                '--dest',
+                'dist/web_modules',
+                maybeOptimize,
+                maybeStats,
+            ],
+            {
+                // Inherit so snowpack's log coloring is passed through
+                stdio: 'inherit',
+            }
+        );
+        proc.on('exit', (code: number) => {
+            if (code > 0) return reject();
+            resolve();
+        });
+    });
+    console.log('\n'); // Just add some spacing...
 }
 
 async function initialBuild(): Promise<void> {
@@ -294,10 +308,9 @@ async function initialBuild(): Promise<void> {
         await snowpack('dist/**/*');
     } catch (err) {
         console.error('\n\nFailed to build with snowpack');
-        console.error(err.stderr || err);
+        err && console.error(err.stderr || err);
         // Don't continue building...
-        if (IS_PRODUCTION_MODE) process.exit(1);
-        return;
+        process.exit(1);
     }
 
     // Transform all generated js files with babel.