[layouts] Add inbuilt validity check to warn when scale bars are

not linked to a map item

(and remove test Web mercator projection warning check)

Author: nyalldawson

src/app/layout/qgslayoutvaliditychecks.cpp

@@ -16,19 +16,25 @@
 
 #include "qgslayoutvaliditychecks.h"
 #include "qgsvaliditycheckcontext.h"
-#include "qgslayoutitemmap.h"
+#include "qgslayoutitemscalebar.h"
 #include "qgslayout.h"
 
-QgsLayoutMapCrsValidityCheck *QgsLayoutMapCrsValidityCheck::create() const
+QgsLayoutScaleBarValidityCheck *QgsLayoutScaleBarValidityCheck::create() const
 {
-  return new QgsLayoutMapCrsValidityCheck();
+  return new QgsLayoutScaleBarValidityCheck();
 }
 
-QString QgsLayoutMapCrsValidityCheck::id() const { return QStringLiteral( "map_crs_check" ); }
+QString QgsLayoutScaleBarValidityCheck::id() const
+{
+  return QStringLiteral( "layout_scalebar_check" );
+}
 
-int QgsLayoutMapCrsValidityCheck::checkType() const { return QgsAbstractValidityCheck::TypeLayoutCheck; }
+int QgsLayoutScaleBarValidityCheck::checkType() const
+{
+  return QgsAbstractValidityCheck::TypeLayoutCheck;
+}
 
-bool QgsLayoutMapCrsValidityCheck::prepareCheck( const QgsValidityCheckContext *context, QgsFeedback * )
+bool QgsLayoutScaleBarValidityCheck::prepareCheck( const QgsValidityCheckContext *context, QgsFeedback * )
 {
   if ( context->type() != QgsValidityCheckContext::TypeLayoutContext )
     return false;
@@ -37,24 +43,25 @@ bool QgsLayoutMapCrsValidityCheck::prepareCheck( const QgsValidityCheckContext *
   if ( !layoutContext )
     return false;
 
-  QList< QgsLayoutItemMap * > mapItems;
-  layoutContext->layout->layoutItems( mapItems );
-  for ( QgsLayoutItemMap *map : qgis::as_const( mapItems ) )
+  QList< QgsLayoutItemScaleBar * > barItems;
+  layoutContext->layout->layoutItems( barItems );
+  for ( QgsLayoutItemScaleBar *bar : qgis::as_const( barItems ) )
   {
-    if ( map->crs().authid() == QStringLiteral( "EPSG:3857" ) )
+    if ( !bar->linkedMap() )
     {
       QgsValidityCheckResult res;
       res.type = QgsValidityCheckResult::Warning;
-      res.title = tr( "Map projection is misleading" );
-      res.detailedDescription = tr( "The projection for the map item %1 is set to <i>Web Mercator (EPSG:3857)</i> which misrepresents areas and shapes. Consider using an appropriate local projection instead." ).arg( map->displayName() );
+      res.title = tr( "Scalebar is not linked to a map" );
+      const QString name = bar->displayName().toHtmlEscaped();
+      res.detailedDescription = tr( "The scalebar “%1” is not linked to a map item. This scale will be misleading." ).arg( name );
       mResults.append( res );
     }
   }
 
   return true;
 }
 
-QList<QgsValidityCheckResult> QgsLayoutMapCrsValidityCheck::runCheck( const QgsValidityCheckContext *, QgsFeedback * )
+QList<QgsValidityCheckResult> QgsLayoutScaleBarValidityCheck::runCheck( const QgsValidityCheckContext *, QgsFeedback * )
 {
   return mResults;
 }

src/app/layout/qgslayoutvaliditychecks.h

@@ -15,14 +15,13 @@
  ***************************************************************************/
 
 #include "qgsabstractvaliditycheck.h"
+#include "qgis_app.h"
 
-class QgsLayoutMapCrsValidityCheck : public QgsAbstractValidityCheck
+class APP_EXPORT QgsLayoutScaleBarValidityCheck : public QgsAbstractValidityCheck
 {
-    Q_OBJECT
-
   public:
 
-    QgsLayoutMapCrsValidityCheck *create() const override;
+    QgsLayoutScaleBarValidityCheck *create() const override;
     QString id() const override;
     int checkType() const override;
     bool prepareCheck( const QgsValidityCheckContext *context, QgsFeedback *feedback ) override;

src/app/qgisapp.cpp

@@ -1233,7 +1233,7 @@ QgisApp::QgisApp( QSplashScreen *splash, bool restorePlugins, bool skipVersionCh
     setIconSizes( size );
   }
 
-  QgsApplication::validityCheckRegistry()->addCheck( new QgsLayoutMapCrsValidityCheck() );
+  QgsApplication::validityCheckRegistry()->addCheck( new QgsLayoutScaleBarValidityCheck() );
 
   mSplash->showMessage( tr( "Initializing file filters" ), Qt::AlignHCenter | Qt::AlignBottom );
   qApp->processEvents();

tests/src/app/CMakeLists.txt

@@ -12,6 +12,7 @@ INCLUDE_DIRECTORIES(
   ${CMAKE_SOURCE_DIR}/src/core/metadata
   ${CMAKE_SOURCE_DIR}/src/core/raster
   ${CMAKE_SOURCE_DIR}/src/core/symbology
+  ${CMAKE_SOURCE_DIR}/src/core/validity
   ${CMAKE_SOURCE_DIR}/src/ui
   ${CMAKE_SOURCE_DIR}/src/gui
   ${CMAKE_SOURCE_DIR}/src/gui/editorwidgets
@@ -113,4 +114,4 @@ ADD_QGIS_TEST(vectorlayersaveasdialogtest testqgsvectorlayersaveasdialog.cpp)
 ADD_QGIS_TEST(maptoolreverselinetest testqgsmaptoolreverseline.cpp)
 ADD_QGIS_TEST(maptooltrimextendfeaturetest testqgsmaptooltrimextendfeature.cpp)
 ADD_QGIS_TEST(projectproperties testqgsprojectproperties.cpp)
-
+ADD_QGIS_TEST(layoutvaliditychecks testqgsapplayoutvaliditychecks.cpp)

tests/src/app/testqgsapplayoutvaliditychecks.cpp

@@ -0,0 +1,106 @@
+/***************************************************************************
+     testqgsapplayoutvaliditychecks.cpp
+     --------------------------------------
+    Date                 : January 2019
+    Copyright            : (C) 2019 Nyall Dawson
+    Email                : nyall dot dawson at gmail dot com
+ ***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+#include "qgstest.h"
+
+#include <QObject>
+#include <QString>
+#include <QStringList>
+
+//qgis includes...
+#include "qgsdataitem.h"
+#include "qgsapplication.h"
+#include "qgslogger.h"
+#include "qgsproject.h"
+#include "qgslayout.h"
+#include "qgslayoutitemscalebar.h"
+#include "qgslayoutitemmap.h"
+#include "qgsabstractvaliditycheck.h"
+#include "qgsvaliditycheckcontext.h"
+#include "layout/qgslayoutvaliditychecks.h"
+#include "qgsfeedback.h"
+
+class TestQgsLayoutValidityChecks : public QObject
+{
+    Q_OBJECT
+
+  public:
+    TestQgsLayoutValidityChecks();
+
+  private slots:
+    void initTestCase();// will be called before the first testfunction is executed.
+    void cleanupTestCase();// will be called after the last testfunction was executed.
+    void init() {} // will be called before each testfunction is executed.
+    void cleanup() {} // will be called after every testfunction.
+
+    void testScaleBarValidity();
+
+  private:
+    QString mTestDataDir;
+};
+
+TestQgsLayoutValidityChecks::TestQgsLayoutValidityChecks() = default;
+
+void TestQgsLayoutValidityChecks::initTestCase()
+{
+  //
+  // Runs once before any tests are run
+  //
+  // init QGIS's paths - true means that all path will be inited from prefix
+  QgsApplication::init();
+  QgsApplication::initQgis();
+  QgsApplication::showSettings();
+
+  QString dataDir( TEST_DATA_DIR ); //defined in CmakeLists.txt
+  mTestDataDir = dataDir + '/';
+}
+
+void TestQgsLayoutValidityChecks::cleanupTestCase()
+{
+  QgsApplication::exitQgis();
+}
+
+void TestQgsLayoutValidityChecks::testScaleBarValidity()
+{
+  QgsProject p;
+  QgsLayout l( &p );
+
+  QgsLayoutItemScaleBar *scale = new QgsLayoutItemScaleBar( &l );
+  l.addItem( scale );
+
+  QgsLayoutValidityCheckContext context( &l );
+  QgsFeedback f;
+
+  // scalebar not linked to map
+  QgsLayoutScaleBarValidityCheck check;
+  QVERIFY( check.prepareCheck( &context, &f ) );
+  QList< QgsValidityCheckResult > res = check.runCheck( &context, &f );
+  QCOMPARE( res.size(), 1 );
+  QCOMPARE( res.at( 0 ).type, QgsValidityCheckResult::Warning );
+
+  // now link a map
+  QgsLayoutItemMap *map = new QgsLayoutItemMap( &l );
+  l.addItem( map );
+  scale->setLinkedMap( map );
+
+  QgsLayoutScaleBarValidityCheck check2;
+  QVERIFY( check2.prepareCheck( &context, &f ) );
+  res = check2.runCheck( &context, &f );
+  QCOMPARE( res.size(), 0 );
+}
+
+
+
+QGSTEST_MAIN( TestQgsLayoutValidityChecks )
+#include "testqgsapplayoutvaliditychecks.moc"