From e4ec4e34737cbd51cdf964b7ec1b37fe6901d88d Mon Sep 17 00:00:00 2001
From: nirvn <nirvn.asia@gmail.com>
Date: Tue, 13 Sep 2016 11:04:33 +0700
Subject: [PATCH] [delimitertext] fix watcher check ignored and harmful watcher
 created for iterator (fixes #15558)

(cherry-picked from b3e31087181732f7511d047b98352e97f08b0d04)
---
 .../delimitedtext/qgsdelimitedtextfeatureiterator.cpp  | 10 +++++++++-
 src/providers/delimitedtext/qgsdelimitedtextfile.cpp   | 10 +++++-----
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/src/providers/delimitedtext/qgsdelimitedtextfeatureiterator.cpp b/src/providers/delimitedtext/qgsdelimitedtextfeatureiterator.cpp
index 55a45a55f188..a1447114d657 100644
--- a/src/providers/delimitedtext/qgsdelimitedtextfeatureiterator.cpp
+++ b/src/providers/delimitedtext/qgsdelimitedtextfeatureiterator.cpp
@@ -502,8 +502,16 @@ QgsDelimitedTextFeatureSource::QgsDelimitedTextFeatureSource( const QgsDelimited
     , mXyDms( p->mXyDms )
     , attributeColumns( p->attributeColumns )
 {
+  QUrl url = p->mFile->url();
+
+  // make sure watcher not created when using iterator (e.g. for rendering, see issue #15558)
+  if ( url.hasQueryItem( "watchFile" ) )
+  {
+    url.removeQueryItem( "watchFile" );
+  }
+
   mFile = new QgsDelimitedTextFile();
-  mFile->setFromUrl( p->mFile->url() );
+  mFile->setFromUrl( url );
 
   mExpressionContext << QgsExpressionContextUtils::globalScope()
   << QgsExpressionContextUtils::projectScope();
diff --git a/src/providers/delimitedtext/qgsdelimitedtextfile.cpp b/src/providers/delimitedtext/qgsdelimitedtextfile.cpp
index a68bc447d19d..8b37fe632387 100644
--- a/src/providers/delimitedtext/qgsdelimitedtextfile.cpp
+++ b/src/providers/delimitedtext/qgsdelimitedtextfile.cpp
@@ -35,7 +35,7 @@ QgsDelimitedTextFile::QgsDelimitedTextFile( const QString& url )
     , mEncoding( "UTF-8" )
     , mFile( nullptr )
     , mStream( nullptr )
-    , mUseWatcher( true )
+    , mUseWatcher( false )
     , mWatcher( nullptr )
     , mDefinitionValid( false )
     , mUseHeader( true )
@@ -158,9 +158,9 @@ bool QgsDelimitedTextFile::setFromUrl( const QUrl &url )
   }
 
   //
-  if ( url.hasQueryItem( "useWatcher" ) )
+  if ( url.hasQueryItem( "watchFile" ) )
   {
-    mUseWatcher = ! url.queryItemValue( "useWatcher" ).toUpper().startsWith( 'N' );
+    mUseWatcher = url.queryItemValue( "watchFile" ).toUpper().startsWith( 'Y' );
   }
 
   // The default type is csv, to be consistent with the
@@ -269,9 +269,9 @@ QUrl QgsDelimitedTextFile::url()
     url.addQueryItem( "encoding", mEncoding );
   }
 
-  if ( !mUseWatcher )
+  if ( mUseWatcher )
   {
-    url.addQueryItem( "useWatcher", "no" );
+    url.addQueryItem( "watchFile", "yes" );
   }
 
   url.addQueryItem( "type", type() );