ClangTools: Give a hint to users as to why we didn't do anything

Task-number: QTCREATORBUG-25565
Change-Id: I27cb0e5bc2a02a88ddf1d42b996e45840d6c1385
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/clangtools/clangtool.cpp

@@ -56,6 +56,7 @@
 #include <projectexplorer/projectexplorericons.h>
 #include <projectexplorer/session.h>
 #include <projectexplorer/target.h>
+#include <projectexplorer/taskhub.h>
 
 #include <texteditor/textdocument.h>
 
@@ -650,6 +651,8 @@ void ClangTool::startTool(ClangTool::FileSelection fileSelection,
                 return;
     }
 
+    TaskHub::clearTasks(taskCategory());
+
     // Collect files to analyze
     const FileInfos fileInfos = collectFileInfos(project, fileSelection);
     if (fileInfos.empty())
@@ -726,8 +729,12 @@ FileInfos ClangTool::collectFileInfos(Project *project, FileSelection fileSelect
     FileSelectionType *selectionType = get_if<FileSelectionType>(&fileSelection);
     // early bailout
     if (selectionType && *selectionType == FileSelectionType::CurrentFile
-        && !EditorManager::currentDocument())
+        && !EditorManager::currentDocument()) {
+        TaskHub::addTask(Task::Error, tr("Cannot analyze current file: No files open."),
+                                         taskCategory());
+        TaskHub::requestPopup();
         return {};
+    }
 
     auto projectInfo = CppTools::CppModelManager::instance()->projectInfo(project);
     QTC_ASSERT(projectInfo.isValid(), return FileInfos());
@@ -757,6 +764,11 @@ FileInfos ClangTool::collectFileInfos(Project *project, FileSelection fileSelect
         });
         if (!fileInfo.file.isEmpty())
             return {fileInfo};
+        TaskHub::addTask(Task::Error,
+                         tr("Cannot analyze current file: \"%1\" is not a known source file.")
+                         .arg(filePath.toUserOutput()),
+                         taskCategory());
+        TaskHub::requestPopup();
     }
 
     return {};

src/plugins/clangtools/clangtoolsplugin.cpp

@@ -60,6 +60,7 @@
 #include <projectexplorer/kitinformation.h>
 #include <projectexplorer/projectpanelfactory.h>
 #include <projectexplorer/target.h>
+#include <projectexplorer/taskhub.h>
 
 #include <QAction>
 #include <QDebug>
@@ -114,6 +115,8 @@ bool ClangToolsPlugin::initialize(const QStringList &arguments, QString *errorSt
     Q_UNUSED(arguments)
     Q_UNUSED(errorString)
 
+    TaskHub::addCategory(taskCategory(), tr("Clang Tools"));
+
     // Import tidy/clazy diagnostic configs from CppTools now
     // instead of at opening time of the settings page
     ClangToolsSettings::instance();

src/plugins/clangtools/clangtoolsutils.h

@@ -27,6 +27,7 @@
 
 #include <cpptools/clangdiagnosticconfig.h>
 
+#include <utils/id.h>
 #include <utils/optional.h>
 
 #include <QtGlobal>
@@ -87,5 +88,7 @@ CppTools::ClangDiagnosticConfig diagnosticConfig(const Utils::Id &diagConfigId);
 QStringList extraClangToolsPrependOptions();
 QStringList extraClangToolsAppendOptions();
 
+inline Utils::Id taskCategory() { return "ClangTools"; }
+
 } // namespace Internal
 } // namespace ClangTools