Clang: Work around missing file

We now generate an empty fake file.

Change-Id: I92fef2b24dce788c1d1b675b034d4b31346b80d9
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

src/tools/clangpchmanagerbackend/source/collectincludesaction.h

@@ -56,6 +56,8 @@ public:
           auto &preprocessor = compilerInstance.getPreprocessor();
           auto &headerSearch = preprocessor.getHeaderSearchInfo();
 
+          preprocessor.SetSuppressIncludeNotFoundError(true);
+
           auto macroPreprocessorCallbacks = new CollectIncludesPreprocessorCallbacks(headerSearch,
                                                                                      m_includeIds,
                                                                                      m_filePathCache,

src/tools/clangpchmanagerbackend/source/collectincludespreprocessorcallbacks.h

@@ -35,6 +35,10 @@
 
 #include <utils/smallstringvector.h>
 
+#include <QFile>
+#include <QDir>
+#include <QTemporaryDir>
+
 #include <algorithm>
 
 namespace ClangBackEnd {
@@ -64,7 +68,7 @@ public:
                             llvm::StringRef /*relativePath*/,
                             const clang::Module * /*imported*/) override
     {
-        if (file) {
+        if (!m_skipInclude && file) {
             auto fileUID = file->getUID();
             if (isNotInExcludedIncludeUID(fileUID)) {
                 flagIncludeAlreadyRead(file);
@@ -80,6 +84,45 @@ public:
                 }
             }
         }
+
+        m_skipInclude = false;
+    }
+
+    bool FileNotFound(clang::StringRef fileNameRef, clang::SmallVectorImpl<char> &recoveryPath) override
+    {
+        QTemporaryDir temporaryDirectory;
+        temporaryDirectory.setAutoRemove(false);
+        const QByteArray temporaryDirUtf8 = temporaryDirectory.path().toUtf8();
+
+        const QString fileName = QString::fromUtf8(fileNameRef.data(), int(fileNameRef.size()));
+        QString filePath = temporaryDirectory.path() + '/' + fileName;
+
+        ensureDirectory(temporaryDirectory.path(), fileName);
+        createFakeFile(filePath);
+
+        recoveryPath.append(temporaryDirUtf8.cbegin(), temporaryDirUtf8.cend());
+
+        m_skipInclude = true;
+
+        return true;
+    }
+
+    void ensureDirectory(const QString &directory, const QString &fileName)
+    {
+        QStringList directoryEntries = fileName.split('/');
+        directoryEntries.pop_back();
+
+        if (!directoryEntries.isEmpty())
+            QDir(directory).mkpath(directoryEntries.join('/'));
+    }
+
+    void createFakeFile(const QString &filePath)
+    {
+        QFile fakeFile;
+        fakeFile.setFileName(filePath);
+
+        fakeFile.open(QIODevice::ReadWrite);
+        fakeFile.close();
     }
 
     bool isNotInExcludedIncludeUID(uint uid) const
@@ -131,6 +174,7 @@ private:
     StringCache<Utils::PathString> &m_filePathCache;
     const std::vector<uint> &m_excludedIncludeUID;
     std::vector<uint> &m_alreadyIncludedFileUIDs;
+    bool m_skipInclude = false;
 };
 
 } // namespace ClangBackEnd

tests/unit/unittest/data/includecollector_missingfile.cpp

+#include "missing_file.moc"
+#include "foo/missing_file.moc"
+#include <missing_file2.moc>
+#include <foo2/missing_file2.moc>
+
+#include "includecollector_external1.h"

tests/unit/unittest/includecollector-test.cpp

@@ -109,6 +109,16 @@ TEST_F(IncludeCollector, LocalPath)
                                      id(TESTDATA_DIR "/includecollector_external3.h")));
 }
 
+TEST_F(IncludeCollector, IgnoreMissingFile)
+{
+    emptyCollector.addFile(TESTDATA_DIR, "includecollector_missingfile.cpp", "", {"cc", "includecollector_missingfile.cpp"});
+
+    emptyCollector.collectIncludes();
+
+    ASSERT_THAT(emptyCollector.takeIncludeIds(),
+                UnorderedElementsAre(id(TESTDATA_DIR "/includecollector_external1.h")));
+}
+
 void IncludeCollector::SetUp()
 {
     collector.addFile(TESTDATA_DIR, "includecollector_main.cpp", "", {"cc", "includecollector_main.cpp"});

tests/unit/unittest/unittests-main.cpp

@@ -39,8 +39,11 @@
 
 int main(int argc, char *argv[])
 {
-    Utils::TemporaryDirectory::setMasterTemporaryDirectory(QDir::tempPath()
-                                                           +"/QtCreator-UnitTests-XXXXXX");
+    const QString temporayDirectoryPath = QDir::tempPath() +"/QtCreator-UnitTests-XXXXXX";
+    Utils::TemporaryDirectory::setMasterTemporaryDirectory(temporayDirectoryPath);
+    qputenv("TMPDIR", Utils::TemporaryDirectory::masterDirectoryPath().toUtf8());
+    qputenv("TEMP", Utils::TemporaryDirectory::masterDirectoryPath().toUtf8());
+
     Sqlite::registerTypes();
 
     QCoreApplication application(argc, argv);