From 01d9b95d4e066c79617435787a77615f52af49b8 Mon Sep 17 00:00:00 2001
From: Simon Hartcher <simon@simonhartcher.com>
Date: Wed, 22 Mar 2017 20:26:14 +1100
Subject: [PATCH] Throttle progress bar output

- Fixes #1389
---
 lib/install.ps1 | 29 ++++++++++++++++++++++-------
 1 file changed, 22 insertions(+), 7 deletions(-)

diff --git a/lib/install.ps1 b/lib/install.ps1
index 8ec8c44450..ae59a96017 100644
--- a/lib/install.ps1
+++ b/lib/install.ps1
@@ -164,8 +164,20 @@ function dl($url, $to, $cookies, $progress) {
 
     if ($progress -and ($total -gt 0)) {
         [console]::CursorVisible = $false
-        function dl_onProgress($read) {
-            dl_progress $read $total $url
+        function dl_onProgress($read, $last) {
+            # get datetime now
+            $now = [System.DateTime]::Now;
+            # subtract from last datetime
+            $delta = $now - $last;
+
+            # output progress only every 100ms
+            if ($delta.TotalMilliseconds -gt 100) {
+                dl_progress $read $total $url
+
+                return $now;
+            }
+
+            return $last;
         }
     } else {
         write-host "Downloading $url ($(filesize $total))..."
@@ -180,13 +192,16 @@ function dl($url, $to, $cookies, $progress) {
         $buffer = new-object byte[] 2048
         $totalRead = 0
 
-        dl_onProgress $totalRead
+        # print starting progress
+        $last = dl_onProgress $totalRead ([DateTime]::MinValue)
         while(($read = $s.read($buffer, 0, $buffer.length)) -gt 0) {
             $fs.write($buffer, 0, $read)
             $totalRead += $read
 
-            dl_onProgress $totalRead
+            $last = dl_onProgress $totalRead $last
         }
+        # make sure we print ending progress
+        dl_onProgress $totalRead ([DateTime]::MinValue)
     } finally {
         if ($progress) {
             [console]::CursorVisible = $true
@@ -254,9 +269,9 @@ function dl_progress_output($url, $read, $total, $console) {
 
 function dl_progress($read, $total, $url) {
     $console = $host.UI.RawUI;
-    $left  = $console.CursorPosition.X;
-    $top   = $console.CursorPosition.Y;
-    $width = $console.BufferSize.Width;
+    $left    = $console.CursorPosition.X;
+    $top     = $console.CursorPosition.Y;
+    $width   = $console.BufferSize.Width;
 
     if($read -eq 0) {
         $maxOutputLength = $(dl_progress_output $url 100 $total $console).length