qt-creator/src/plugins/cpptools/cppprojectpartchooser.cpp

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#include "cppprojectpartchooser.h"

#include <utils/algorithm.h>
#include <utils/qtcassert.h>

namespace CppTools {
namespace Internal {

static bool isPreferredLanguage(const ProjectPart &projectPart, Language preference)
{
    const bool isCProjectPart = projectPart.languageVersion <= ProjectPart::LatestCVersion;
    return (preference == Language::C && isCProjectPart)
        || (preference == Language::Cxx && !isCProjectPart);
}

static int priority(const ProjectPart &projectPart,
                    const ProjectExplorer::Project *activeProject,
                    Language languagePreference)
{
    int thePriority = 0;

    if (projectPart.project == activeProject)
        thePriority += 100;

    if (projectPart.selectedForBuilding)
        thePriority += 10;

    if (isPreferredLanguage(projectPart, languagePreference))
        thePriority += 1;

    return thePriority;
}

static ProjectPart::Ptr chooseFromMultiple(const QList<ProjectPart::Ptr> &projectParts,
                                           const ProjectExplorer::Project *activeProject,
                                           Language languagePreference)
{
    QList<ProjectPart::Ptr> projectPartsPrioritized = projectParts;
    const auto lessThan = [&] (const ProjectPart::Ptr &p1, const ProjectPart::Ptr &p2) {
        return priority(*p1, activeProject, languagePreference)
             > priority(*p2, activeProject, languagePreference);
    };
    std::stable_sort(projectPartsPrioritized.begin(), projectPartsPrioritized.end(), lessThan);

    return projectPartsPrioritized.first();
}

ProjectPart::Ptr ProjectPartChooser::choose(const QString &filePath,
                                            const ProjectPart::Ptr &currentProjectPart,
                                            const ProjectPart::Ptr &manuallySetProjectPart,
                                            bool stickToPreviousProjectPart,
                                            const ProjectExplorer::Project *activeProject,
                                            Language languagePreference,
                                            bool projectHasChanged) const
{
    QTC_CHECK(m_projectPartsForFile);
    QTC_CHECK(m_projectPartsFromDependenciesForFile);
    QTC_CHECK(m_fallbackProjectPart);

    if (manuallySetProjectPart)
        return manuallySetProjectPart;

    ProjectPart::Ptr projectPart = currentProjectPart;

    QList<ProjectPart::Ptr> projectParts = m_projectPartsForFile(filePath);
    if (projectParts.isEmpty()) {
        if (projectPart && stickToPreviousProjectPart)
            // File is not directly part of any project, but we got one before. We will re-use it,
            // because re-calculating this can be expensive when the dependency table is big.
            return projectPart;

        // Fall-back step 1: Get some parts through the dependency table:
        projectParts = m_projectPartsFromDependenciesForFile(filePath);
        if (projectParts.isEmpty())
            // Fall-back step 2: Use fall-back part from the model manager:
            projectPart = m_fallbackProjectPart();
        else
            projectPart = chooseFromMultiple(projectParts, activeProject, languagePreference);
    } else {
        if (projectHasChanged || !projectParts.contains(projectPart))
            projectPart = chooseFromMultiple(projectParts, activeProject, languagePreference);
    }

    return projectPart;
}

void ProjectPartChooser::setFallbackProjectPart(const FallBackProjectPart &getter)
{
    m_fallbackProjectPart = getter;
}

void ProjectPartChooser::setProjectPartsForFile(const ProjectPartsForFile &getter)
{
    m_projectPartsForFile = getter;
}

void ProjectPartChooser::setProjectPartsFromDependenciesForFile(
        const ProjectPartsFromDependenciesForFile &getter)
{
    m_projectPartsFromDependenciesForFile = getter;
}

} // namespace Internal
} // namespace CppTools