From d51c508ba5a268bd65561076ade9da4ad16b122f Mon Sep 17 00:00:00 2001
From: Pooya Parsa <pyapar@gmail.com>
Date: Sat, 10 Nov 2018 01:23:13 +0330
Subject: [PATCH] feat(log-update): support concurrent writes to stdout/stderr
 on render

---
 src/reporters/fancy.js  | 17 +----------
 src/utils/log-update.js | 67 ++++++++++++++++++++++++++++++++++++++---
 2 files changed, 63 insertions(+), 21 deletions(-)

diff --git a/src/reporters/fancy.js b/src/reporters/fancy.js
index 7866060..e4317df 100644
--- a/src/reporters/fancy.js
+++ b/src/reporters/fancy.js
@@ -1,6 +1,5 @@
 /* eslint-disable no-console */
 import chalk from 'chalk';
-import consola from 'consola';
 
 import { renderBar, colorize, ellipsisLeft } from '../utils/cli';
 import { formatRequest } from '../utils/webpack';
@@ -12,29 +11,15 @@ const logUpdate = new LogUpdate();
 let lastRender = Date.now();
 
 export default class FancyReporter {
-  start() {
-    // TODO: remove in next major release.
-    // Some projects still depend on legacy versions of consola
-    if (typeof consola.pause === 'function') {
-      consola.pause();
-    }
-  }
-
   allDone() {
     logUpdate.done();
-
-    if (typeof consola.resume === 'function') {
-      consola.resume();
-    }
   }
 
   done(context) {
     this._renderStates(context.statesArray);
 
     if (context.hasErrors) {
-      if (typeof consola.resume === 'function') {
-        consola.resume();
-      }
+      logUpdate.done();
     }
   }
 
diff --git a/src/utils/log-update.js b/src/utils/log-update.js
index 151f9fc..e65940c 100644
--- a/src/utils/log-update.js
+++ b/src/utils/log-update.js
@@ -6,20 +6,30 @@ import wrapAnsi from 'wrap-ansi';
 export default class LogUpdate {
   constructor() {
     this.prevLineCount = 0;
+    this.listening = false;
+    this.extraLines = '';
+    this._onData = this._onData.bind(this);
+    this._streams = [process.stdout, process.stderr];
   }
 
   render(lines) {
+    this.listen();
+
     const wrappedLines = wrapAnsi(lines, this.columns, {
       trim: false,
       hard: true,
       wordWrap: false,
     });
 
-    const earaseChars = ansiEscapes.eraseLines(this.prevLineCount);
+    const data =
+      ansiEscapes.eraseLines(this.prevLineCount) +
+      wrappedLines +
+      '\n' +
+      this.extraLines;
 
-    this.write(earaseChars + wrappedLines + '\n');
+    this.write(data);
 
-    this.prevLineCount = wrappedLines.split('\n').length + 1;
+    this.prevLineCount = data.split('\n').length;
   }
 
   get columns() {
@@ -27,15 +37,62 @@ export default class LogUpdate {
   }
 
   write(data) {
-    process.stderr.write(data, 'utf-8');
+    if (process.stderr.__write) {
+      process.stderr.__write(data, 'utf-8');
+    } else {
+      process.stderr.write(data, 'utf-8');
+    }
   }
 
   clear() {
+    this.done();
     this.write(ansiEscapes.eraseLines(this.prevLineCount));
-    this.prevLineCount = 0;
   }
 
   done() {
+    this.stopListen();
+
     this.prevLineCount = 0;
+    this.extraLines = '';
+  }
+
+  _onData(data) {
+    const str = String(data);
+    const lines = str.split('\n').length - 1;
+    if (lines > 0) {
+      this.prevLineCount += lines;
+      this.extraLines += data;
+    }
+  }
+
+  listen() {
+    if (this.listening) {
+      return;
+    }
+
+    const t = this;
+
+    for (const stream of this._streams) {
+      if (!stream.__write) {
+        stream.__write = stream.write;
+        stream.write = function write(data, ...args) {
+          t._onData(data);
+          this.__write(data, ...args);
+        };
+      }
+    }
+
+    this.listening = true;
+  }
+
+  stopListen() {
+    for (const stream of this._streams) {
+      if (stream.__write) {
+        stream.write = stream.__write;
+        delete stream.__write;
+      }
+    }
+
+    this.listening = false;
   }
 }