Add more detailed error messages

Once installer is started, metadata is downloaded to cache and that
cache is used later to speed the installation process. Cache should not
get invalid but sometimes that can happen. Informing user where the
cache exists and that clearing it might help when the error occurs.

Task-number: QTIFW-2998
Change-Id: Ia2c2a1209fa84070f9ad337c63a429a1afd721a7
Reviewed-by: Arttu Tarkiainen <arttu.tarkiainen@qt.io>

4 files changed, 24 insertions, 19 deletions

diff --git a/src/libs/installer/component.cpp b/src/libs/installer/component.cpp
index 690b4ee93..edd03a191 100644
--- a/src/libs/installer/component.cpp
+++ b/src/libs/installer/component.cpp
@@ -64,9 +64,6 @@
 
 using namespace QInstaller;
 
-static const char *scClearCacheHint = QT_TR_NOOP(
-    "Clearing the cache directory and restarting the application may solve this.");
-
 /*!
     \enum QInstaller::Component::UnstableError
 
@@ -692,8 +689,8 @@ void Component::loadUserInterfaces(const QDir &directory, const QStringList &uis
     while (it.hasNext()) {
         QFile file(it.next());
         if (!file.open(QIODevice::ReadOnly)) {
-            throw Error(tr("Cannot open the requested UI file \"%1\": %2.\n\n%3").arg(
-                            it.fileName(), file.errorString(), tr(scClearCacheHint)));
+            throw Error(tr("Cannot open the requested UI file \"%1\": %2.\n\n%3 \"%4\"").arg(
+                            it.fileName(), file.errorString(), tr(scClearCacheHint), packageManagerCore()->settings().localCachePath()));
         }
 
         static QUiLoader loader;
@@ -701,8 +698,8 @@ void Component::loadUserInterfaces(const QDir &directory, const QStringList &uis
         loader.setLanguageChangeEnabled(true);
         QWidget *const widget = loader.load(&file, 0);
         if (!widget) {
-            throw Error(tr("Cannot load the requested UI file \"%1\": %2.\n\n%3").arg(
-                            it.fileName(), loader.errorString(), tr(scClearCacheHint)));
+            throw Error(tr("Cannot load the requested UI file \"%1\": %2.\n\n%3 \"%4\"").arg(
+                            it.fileName(), loader.errorString(), tr(scClearCacheHint), packageManagerCore()->settings().localCachePath()));
         }
         d->scriptEngine()->newQObject(widget);
         d->m_userInterfaces.insert(widget->objectName(), widget);
@@ -747,8 +744,8 @@ void Component::loadLicenses(const QString &directory, const QHash<QString, QVar
 
         QFile file(fileInfo.filePath());
         if (!file.open(QIODevice::ReadOnly)) {
-            throw Error(tr("Cannot open the requested license file \"%1\": %2.\n\n%3").arg(
-                            file.fileName(), file.errorString(), tr(scClearCacheHint)));
+            throw Error(tr("Cannot open the requested license file \"%1\": %2.\n\n%3 \"%4\"").arg(
+                            file.fileName(), file.errorString(), tr(scClearCacheHint), packageManagerCore()->settings().localCachePath()));
         }
         QTextStream stream(&file);
         stream.setCodec("UTF-8");
diff --git a/src/libs/installer/constants.h b/src/libs/installer/constants.h
index 1ac1d8940..ecd85fe11 100644
--- a/src/libs/installer/constants.h
+++ b/src/libs/installer/constants.h
@@ -1,6 +1,6 @@
 /**************************************************************************
 **
-** Copyright (C) 2022 The Qt Company Ltd.
+** Copyright (C) 2023 The Qt Company Ltd.
 ** Contact: https://www.qt.io/licensing/
 **
 ** This file is part of the Qt Installer Framework.
@@ -75,6 +75,9 @@ static const QLatin1String scMetadataName("MetadataName");
 static const QLatin1String scContentSha1("ContentSha1");
 static const QLatin1String scCheckSha1CheckSum("CheckSha1CheckSum");
 
+static const char *scClearCacheHint = QT_TR_NOOP(
+    "This may be solved by restarting the application after clearing the cache from:");
+
 // symbols
 static const QLatin1String scCaretSymbol("^");
 static const QLatin1String scCommaWithSpace(", ");
diff --git a/src/libs/installer/scriptengine.cpp b/src/libs/installer/scriptengine.cpp
index bcd475d54..baf348868 100644
--- a/src/libs/installer/scriptengine.cpp
+++ b/src/libs/installer/scriptengine.cpp
@@ -1,6 +1,6 @@
 /**************************************************************************
 **
-** Copyright (C) 2022 The Qt Company Ltd.
+** Copyright (C) 2023 The Qt Company Ltd.
 ** Contact: https://www.qt.io/licensing/
 **
 ** This file is part of the Qt Installer Framework.
@@ -34,6 +34,7 @@
 #include "loggingutils.h"
 #include "packagemanagergui.h"
 #include "component.h"
+#include "settings.h"
 
 #include <QMetaEnum>
 #include <QQmlEngine>
@@ -377,9 +378,9 @@ QString QFileDialogProxy::getExistingFileOrDirectory(const QString &caption,
 /*!
     Constructs a script engine with \a core as parent.
 */
-ScriptEngine::ScriptEngine(PackageManagerCore *core) :
-    QObject(core),
-    m_guiProxy(new GuiProxy(this, this))
+ScriptEngine::ScriptEngine(PackageManagerCore *core) : QObject(core)
+    , m_guiProxy(new GuiProxy(this, this))
+    , m_core(core)
 {
     m_engine.installExtensions(QJSEngine::TranslationExtension);
     QJSValue global = m_engine.globalObject();
@@ -574,14 +575,17 @@ QJSValue ScriptEngine::callScriptMethod(const QJSValue &scriptContext, const QSt
     if (!method.isCallable())
         return QJSValue(QJSValue::UndefinedValue);
     if (method.isError()) {
-        throw Error(method.toString().isEmpty() ? QString::fromLatin1("Unknown error.")
-            : method.toString());
+        QString errorString = method.toString().isEmpty() ? QString::fromLatin1("Unknown error.")
+            : method.toString();
+
+        throw Error(QString::fromLatin1("%1 \n%2 \"%3\"").arg(errorString, tr(scClearCacheHint), m_core->settings().localCachePath()));
     }
 
     const QJSValue result = method.call(arguments);
     if (result.isError()) {
-        throw Error(result.toString().isEmpty() ? QString::fromLatin1("Unknown error.")
-            : result.toString());
+        QString errorString = result.toString().isEmpty() ? QString::fromLatin1("Unknown error.")
+            : result.toString();
+        throw Error(QString::fromLatin1("%1 \n%2 \"%3\"").arg(errorString, tr(scClearCacheHint), m_core->settings().localCachePath()));
     }
 
     stack.removeLast();
diff --git a/src/libs/installer/scriptengine.h b/src/libs/installer/scriptengine.h
index a7c0ef253..0b43465cb 100644
--- a/src/libs/installer/scriptengine.h
+++ b/src/libs/installer/scriptengine.h
@@ -1,6 +1,6 @@
 /**************************************************************************
 **
-** Copyright (C) 2022 The Qt Company Ltd.
+** Copyright (C) 2023 The Qt Company Ltd.
 ** Contact: https://www.qt.io/licensing/
 **
 ** This file is part of the Qt Installer Framework.
@@ -77,6 +77,7 @@ private:
     QJSEngine m_engine;
     QHash<QString, QStringList> m_callstack;
     GuiProxy *m_guiProxy;
+    PackageManagerCore *m_core;
 };
 
 }