fix(copy): use fs.copyFile and reduce concurrent copy tasks

Author: adamdbradley

src/compiler/copy/copy-tasks-worker.ts

@@ -18,9 +18,13 @@ export async function copyTasksWorker(copyTasks: d.CopyTask[]) {
 
     // figure out all the file copy tasks we'll have
     // by digging down through any directory copy tasks
-    await Promise.all(copyTasks.map(async copyTask => {
-      await processCopyTask(fs, results, allCopyTasks, copyTask);
-    }));
+    while (copyTasks.length > 0) {
+      const tasks = copyTasks.splice(0, 100);
+
+      await Promise.all(tasks.map(async copyTask => {
+        await processCopyTask(fs, results, allCopyTasks, copyTask);
+      }));
+    }
 
     // figure out which directories we'll need to make first
     const mkDirs = ensureDirs(allCopyTasks);
@@ -30,10 +34,13 @@ export async function copyTasksWorker(copyTasks: d.CopyTask[]) {
       } catch (mkDirErr) {}
     }
 
-    // begin copying all the files
-    await Promise.all(allCopyTasks.map(async copyTask => {
-      await fs.copyFile(copyTask.src, copyTask.dest);
-    }));
+    while (allCopyTasks.length > 0) {
+      const tasks = allCopyTasks.splice(0, 100);
+
+      await Promise.all(tasks.map(async copyTask => {
+        await fs.copyFile(copyTask.src, copyTask.dest);
+      }));
+    }
 
   } catch (e) {
     catchError(results.diagnostics, e);

src/sys/node/node-fs.ts

@@ -6,14 +6,25 @@ export class NodeFs implements d.FileSystem {
 
   copyFile(src: string, dest: string) {
     return new Promise<void>((resolve, reject) => {
-      const readStream = fs.createReadStream(src);
-      readStream.on('error', reject);
-
-      const writeStream = fs.createWriteStream(dest);
-      writeStream.on('error', reject);
-      writeStream.on('close', resolve);
-
-      readStream.pipe(writeStream);
+      if (typeof fs.copyFile === 'function') {
+        fs.copyFile(src, dest, fs.constants.COPYFILE_FICLONE, (err) => {
+          if (err) {
+            reject(err);
+          } else {
+            resolve();
+          }
+        });
+
+      } else {
+        const readStream = fs.createReadStream(src);
+        readStream.on('error', reject);
+
+        const writeStream = fs.createWriteStream(dest);
+        writeStream.on('error', reject);
+        writeStream.on('close', resolve);
+
+        readStream.pipe(writeStream);
+      }
     });
   }