Qmake: Improve the build dir location warning

The infamous "build dir is not at the same level at source dir" warning
for qmake projects has gone through a number of iterations in Qt
Creator, having been added, removed and re-added, always to the
criticism of some users. Our new approach is as follows:
    - The warning appears at the widgets where the build directory is
set, both in the target setup page and the build config widget.
    - The warning also appears in the issues pane, but only if the build
failed.
    - The user can disable the warning altogether in a newly introduced
qmake settings page.
    - This option is disabled by default on Unix, because to my
knowledge all failure reports have been for Windows hosts.
This should finally please everybody.

Fixes: QTCREATORBUG-16945
Change-Id: I638be1f15e8c260a5d72047d6850a3a0f685cf03
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>

src/plugins/projectexplorer/abstractprocessstep.h

@@ -57,6 +57,7 @@ protected:
     ~AbstractProcessStep() override;
     bool init() override;
     void doRun() override;
+    virtual void finish(bool success);
 
     virtual void processStarted();
     virtual void processFinished(int exitCode, QProcess::ExitStatus status);
@@ -68,7 +69,6 @@ protected:
     void doCancel() override;
 
 private:
-    virtual void finish(bool success);
 
     void processReadyReadStdOutput();
     void processReadyReadStdError();

src/plugins/qmakeprojectmanager/qmakebuildconfiguration.cpp

@@ -31,6 +31,7 @@
 #include "qmakeprojectconfigwidget.h"
 #include "qmakeprojectmanagerconstants.h"
 #include "qmakenodes.h"
+#include "qmakesettings.h"
 #include "qmakestep.h"
 #include "qmakemakestep.h"
 #include "makefileparse.h"
@@ -293,6 +294,23 @@ void QmakeBuildConfiguration::emitProFileEvaluateNeeded()
         static_cast<QmakeProject *>(p)->scheduleAsyncUpdate();
 }
 
+QString QmakeBuildConfiguration::unalignedBuildDirWarning()
+{
+    return tr("The build directory should be at the same level as the source directory.");
+}
+
+bool QmakeBuildConfiguration::isBuildDirAtSafeLocation(const QString &sourceDir,
+                                                       const QString &buildDir)
+{
+    return buildDir.count('/') == sourceDir.count('/');
+}
+
+bool QmakeBuildConfiguration::isBuildDirAtSafeLocation() const
+{
+    return isBuildDirAtSafeLocation(project()->projectDirectory().toString(),
+                                    buildDirectory().toString());
+}
+
 void QmakeBuildConfiguration::emitQMakeBuildConfigurationChanged()
 {
     emit qmakeBuildConfigurationChanged();
@@ -571,19 +589,11 @@ QmakeBuildConfigurationFactory::QmakeBuildConfigurationFactory()
         QList<Task> issues;
         if (version)
             issues << version->reportIssues(projectPath, buildDir);
-
-        QString tmpBuildDir = QDir(buildDir).absolutePath();
-        const QChar slash = QLatin1Char('/');
-        if (!tmpBuildDir.endsWith(slash))
-            tmpBuildDir.append(slash);
-        QString sourcePath = QFileInfo(projectPath).absolutePath();
-        if (!sourcePath.endsWith(slash))
-            sourcePath.append(slash);
-        if (tmpBuildDir.count(slash) != sourcePath.count(slash)) {
-            const QString msg = QCoreApplication::translate("QmakeProjectManager::QtVersion",
-                                                            "The build directory needs to be at the same level as the source directory.");
-
-            issues.append(Task(Task::Warning, msg, Utils::FileName(), -1,
+        if (QmakeSettings::warnAgainstUnalignedBuildDir()
+                && !QmakeBuildConfiguration::isBuildDirAtSafeLocation(
+                    QDir(projectPath).absolutePath(), QDir(buildDir).absolutePath())) {
+            issues.append(Task(Task::Warning, QmakeBuildConfiguration::unalignedBuildDirWarning(),
+                               Utils::FileName(), -1,
                                ProjectExplorer::Constants::TASK_CATEGORY_BUILDSYSTEM));
         }
         return issues;

src/plugins/qmakeprojectmanager/qmakebuildconfiguration.h

@@ -101,6 +101,10 @@ public:
 
     void emitProFileEvaluateNeeded();
 
+    static QString unalignedBuildDirWarning();
+    static bool isBuildDirAtSafeLocation(const QString &sourceDir, const QString &buildDir);
+    bool isBuildDirAtSafeLocation() const;
+
 signals:
     /// emitted for setQMakeBuildConfig, not emitted for Qt version changes, even
     /// if those change the qmakebuildconfig

src/plugins/qmakeprojectmanager/qmakemakestep.cpp

@@ -30,6 +30,7 @@
 #include "qmakenodes.h"
 #include "qmakebuildconfiguration.h"
 #include "qmakeprojectmanagerconstants.h"
+#include "qmakesettings.h"
 
 #include <coreplugin/variablechooser.h>
 #include <projectexplorer/target.h>
@@ -38,6 +39,7 @@
 #include <projectexplorer/gnumakeparser.h>
 #include <projectexplorer/processparameters.h>
 #include <projectexplorer/projectexplorer.h>
+#include <projectexplorer/projectexplorerconstants.h>
 #include <projectexplorer/kitinformation.h>
 #include <projectexplorer/xcodebuildparser.h>
 #include <utils/qtcprocess.h>
@@ -168,6 +170,7 @@ bool QmakeMakeStep::init()
                                          // it has a low priority.
 
     m_scriptTarget = (static_cast<QmakeProject *>(bc->target()->project())->rootProjectNode()->projectType() == ProjectType::ScriptTemplate);
+    m_unalignedBuildDir = !bc->isBuildDirAtSafeLocation();
 
     return AbstractProcessStep::init();
 }
@@ -190,6 +193,18 @@ void QmakeMakeStep::doRun()
     AbstractProcessStep::doRun();
 }
 
+void QmakeMakeStep::finish(bool success)
+{
+    if (!success && !isCanceled() && m_unalignedBuildDir
+            && QmakeSettings::warnAgainstUnalignedBuildDir()) {
+        const QString msg = tr("The build directory is not at the same level as the source "
+                               "directory, which could be the reason for the build failure.");
+        emit addTask(Task(Task::Warning, msg, Utils::FileName(), -1,
+                          ProjectExplorer::Constants::TASK_CATEGORY_BUILDSYSTEM));
+    }
+    MakeStep::finish(success);
+}
+
 ///
 // QmakeMakeStepFactory
 ///

src/plugins/qmakeprojectmanager/qmakemakestep.h

@@ -54,12 +54,14 @@ public:
 
     QmakeBuildConfiguration *qmakeBuildConfiguration() const;
 
+private:
+    void finish(bool success) override;
     bool init() override;
     void doRun() override;
 
-private:
     bool m_scriptTarget = false;
     QString m_makeFileToCheck;
+    bool m_unalignedBuildDir;
 };
 
 } // QmakeProjectManager

src/plugins/qmakeprojectmanager/qmakeprojectconfigwidget.cpp

@@ -28,6 +28,7 @@
 #include "qmakeproject.h"
 #include "qmakebuildconfiguration.h"
 #include "qmakenodes.h"
+#include "qmakesettings.h"
 #include "ui_qmakeprojectconfigwidget.h"
 
 #include <coreplugin/coreicons.h>
@@ -111,6 +112,8 @@ QmakeProjectConfigWidget::QmakeProjectConfigWidget(QmakeBuildConfiguration *bc)
             this, &QmakeProjectConfigWidget::updateProblemLabel);
     connect(project, &Project::parsingFinished,
             this, &QmakeProjectConfigWidget::updateProblemLabel);
+    connect(&QmakeSettings::instance(), &QmakeSettings::settingsChanged,
+            this, &QmakeProjectConfigWidget::updateProblemLabel);
 
     connect(bc->target(), &Target::kitChanged, this, &QmakeProjectConfigWidget::updateProblemLabel);
 
@@ -250,6 +253,11 @@ void QmakeProjectConfigWidget::updateProblemLabel()
         }
     }
 
+    const bool unalignedBuildDir = QmakeSettings::warnAgainstUnalignedBuildDir()
+            && !m_buildConfiguration->isBuildDirAtSafeLocation();
+    if (unalignedBuildDir)
+        allGood = false;
+
     if (allGood) {
         QString buildDirectory = m_buildConfiguration->target()->project()->projectDirectory().toString();
         if (m_buildConfiguration->isShadowBuild())
@@ -293,6 +301,9 @@ void QmakeProjectConfigWidget::updateProblemLabel()
                         .arg(errorString)
                         .arg(m_buildConfiguration->buildDirectory().toUserOutput()));
         return;
+    } else if (unalignedBuildDir) {
+        setProblemLabel(m_buildConfiguration->unalignedBuildDirWarning());
+        return;
     }
 
     setProblemLabel(QString());

src/plugins/qmakeprojectmanager/qmakeprojectmanager.pro

@@ -12,6 +12,7 @@ HEADERS += \
     qmakeprojectmanagerplugin.h \
     qmakeprojectmanager.h \
     qmakeproject.h \
+    qmakesettings.h \
     qmakenodes.h \
     qmakenodetreebuilder.h \
     profileeditor.h \
@@ -52,6 +53,7 @@ SOURCES += \
     qmakeprojectmanager.cpp \
     qmakeproject.cpp \
     qmakenodes.cpp \
+    qmakesettings.cpp \
     qmakenodetreebuilder.cpp \
     profileeditor.cpp \
     profilehighlighter.cpp \

src/plugins/qmakeprojectmanager/qmakeprojectmanager.qbs

@@ -41,6 +41,7 @@ Project {
                 "qmakeparser.cpp", "qmakeparser.h",
                 "qmakeparsernodes.cpp", "qmakeparsernodes.h",
                 "qmakeprojectimporter.cpp", "qmakeprojectimporter.h",
+                "qmakesettings.cpp", "qmakesettings.h",
                 "qmakestep.cpp", "qmakestep.h", "qmakestep.ui",
                 "qmakebuildconfiguration.cpp", "qmakebuildconfiguration.h",
                 "qmakenodes.cpp", "qmakenodes.h",

src/plugins/qmakeprojectmanager/qmakeprojectmanagerplugin.cpp

@@ -28,6 +28,7 @@
 #include "profileeditor.h"
 #include "qmakeprojectmanager.h"
 #include "qmakenodes.h"
+#include "qmakesettings.h"
 #include "qmakestep.h"
 #include "qmakemakestep.h"
 #include "qmakebuildconfiguration.h"
@@ -102,6 +103,8 @@ public:
 
     ProFileEditorFactory profileEditorFactory;
 
+    QmakeSettingsPage settingsPage;
+
     ExternalQtEditor *m_designerEditor{ExternalQtEditor::createDesignerEditor()};
     ExternalQtEditor *m_linguistEditor{ExternalQtEditor::createLinguistEditor()};
 

src/plugins/qmakeprojectmanager/qmakesettings.cpp

@@ -0,0 +1,141 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt Creator.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+****************************************************************************/
+
+#include "qmakesettings.h"
+
+#include <coreplugin/icore.h>
+#include <projectexplorer/projectexplorerconstants.h>
+#include <utils/hostosinfo.h>
+
+#include <QCheckBox>
+#include <QCoreApplication>
+#include <QVBoxLayout>
+
+namespace QmakeProjectManager {
+namespace Internal {
+
+const char BUILD_DIR_WARNING_KEY[] = "QmakeProjectManager/WarnAgainstUnalignedBuildDir";
+
+static bool operator==(const QmakeSettingsData &s1, const QmakeSettingsData &s2)
+{
+    return s1.warnAgainstUnalignedBuildDir == s2.warnAgainstUnalignedBuildDir;
+}
+static bool operator!=(const QmakeSettingsData &s1, const QmakeSettingsData &s2)
+{
+    return !(s1 == s2);
+}
+
+bool QmakeSettings::warnAgainstUnalignedBuildDir()
+{
+    return instance().m_settings.warnAgainstUnalignedBuildDir;
+}
+
+QmakeSettings &QmakeSettings::instance()
+{
+    static QmakeSettings theSettings;
+    return theSettings;
+}
+
+void QmakeSettings::setSettingsData(const QmakeSettingsData &settings)
+{
+    if (instance().m_settings != settings) {
+        instance().m_settings = settings;
+        instance().storeSettings();
+        emit instance().settingsChanged();
+    }
+}
+
+QmakeSettings::QmakeSettings()
+{
+    loadSettings();
+}
+
+void QmakeSettings::loadSettings()
+{
+    m_settings.warnAgainstUnalignedBuildDir = Core::ICore::settings()->value(
+                BUILD_DIR_WARNING_KEY, Utils::HostOsInfo::isWindowsHost()).toBool();
+}
+
+void QmakeSettings::storeSettings() const
+{
+    Core::ICore::settings()->setValue(BUILD_DIR_WARNING_KEY, warnAgainstUnalignedBuildDir());
+}
+
+class QmakeSettingsPage::SettingsWidget : public QWidget
+{
+    Q_DECLARE_TR_FUNCTIONS(QmakeProjectManager::Internal::QmakeSettingsPage)
+public:
+    SettingsWidget()
+    {
+        m_warnAgainstUnalignedBuildDirCheckbox.setText(tr("Warn if a project's source and "
+            "build directories are not at the same level"));
+        m_warnAgainstUnalignedBuildDirCheckbox.setToolTip(tr("Qmake has subtle bugs that "
+            "can trigger if source and build directory are not at the same level."));
+        m_warnAgainstUnalignedBuildDirCheckbox.setChecked(
+                    QmakeSettings::warnAgainstUnalignedBuildDir());
+        const auto layout = new QVBoxLayout(this);
+        layout->addWidget(&m_warnAgainstUnalignedBuildDirCheckbox);
+        layout->addStretch(1);
+    }
+
+    void apply()
+    {
+        QmakeSettingsData settings;
+        settings.warnAgainstUnalignedBuildDir = m_warnAgainstUnalignedBuildDirCheckbox.isChecked();
+        QmakeSettings::setSettingsData(settings);
+    }
+
+private:
+    QCheckBox m_warnAgainstUnalignedBuildDirCheckbox;
+};
+
+QmakeSettingsPage::QmakeSettingsPage()
+{
+    setId("K.QmakeProjectManager.QmakeSettings");
+    setDisplayName(tr("Qmake"));
+    setCategory(ProjectExplorer::Constants::BUILD_AND_RUN_SETTINGS_CATEGORY);
+}
+
+QWidget *QmakeSettingsPage::widget()
+{
+    if (!m_widget)
+        m_widget = new SettingsWidget;
+    return m_widget;
+
+}
+
+void QmakeSettingsPage::apply()
+{
+    if (m_widget)
+        m_widget->apply();
+}
+
+void QmakeSettingsPage::finish()
+{
+    delete m_widget;
+}
+
+} // namespace Internal
+} // namespace QmakeProjectManager

src/plugins/qmakeprojectmanager/qmakesettings.h

@@ -0,0 +1,76 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt Creator.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+****************************************************************************/
+
+#pragma once
+
+#include <coreplugin/dialogs/ioptionspage.h>
+
+#include <QObject>
+#include <QPointer>
+
+namespace QmakeProjectManager {
+namespace Internal {
+
+class QmakeSettingsData {
+public:
+    bool warnAgainstUnalignedBuildDir = false;
+};
+
+class QmakeSettings : public QObject
+{
+    Q_OBJECT
+public:
+    static QmakeSettings &instance();
+    static bool warnAgainstUnalignedBuildDir();
+    static void setSettingsData(const QmakeSettingsData &settings);
+
+signals:
+    void settingsChanged();
+
+private:
+    QmakeSettings();
+    void loadSettings();
+    void storeSettings() const;
+
+    QmakeSettingsData m_settings;
+};
+
+class QmakeSettingsPage : public Core::IOptionsPage
+{
+    Q_OBJECT
+public:
+    QmakeSettingsPage();
+
+private:
+    QWidget *widget() override;
+    void apply() override;
+    void finish() override;
+
+    class SettingsWidget;
+    QPointer<SettingsWidget> m_widget;
+};
+
+} // namespace Internal
+} // namespace QmakeProjectManager