ClangPchManager: Improve handling of no include in project PCH

We were doing simply nothing but we should call
PchCreator::doInMainThreadAfterFinished().

Change-Id: Ia21d2cf4af53121d9e401f6e9a5b432a4daed00f
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

3 files changed, 36 insertions, 9 deletions

diff --git a/src/tools/clangpchmanagerbackend/source/pchcreator.cpp b/src/tools/clangpchmanagerbackend/source/pchcreator.cpp
index 9416e310aa..cd7b492868 100644
--- a/src/tools/clangpchmanagerbackend/source/pchcreator.cpp
+++ b/src/tools/clangpchmanagerbackend/source/pchcreator.cpp
@@ -113,8 +113,11 @@ Utils::SmallStringVector PchCreator::generateClangCompilerArguments(const PchTas
 void PchCreator::generatePch(PchTask &&pchTask)
 {
     m_projectPartPch.projectPartId = pchTask.projectPartId();
-
     m_projectPartPch.lastModified = QDateTime::currentSecsSinceEpoch();
+
+    if (pchTask.includes.empty())
+        return;
+
     auto content = generatePchIncludeFileContent(pchTask.includes);
     auto pchOutputPath = generatePchFilePath();
 
diff --git a/src/tools/clangpchmanagerbackend/source/pchtaskqueue.cpp b/src/tools/clangpchmanagerbackend/source/pchtaskqueue.cpp
index 1edbe15806..b9d6a48fe3 100644
--- a/src/tools/clangpchmanagerbackend/source/pchtaskqueue.cpp
+++ b/src/tools/clangpchmanagerbackend/source/pchtaskqueue.cpp
@@ -33,6 +33,8 @@
 
 #include <utils/algorithm.h>
 
+#include <iostream>
+
 namespace ClangBackEnd {
 
 void PchTaskQueue::addPchTasks(PchTasks &&newPchTasks, PchTasks &destination)
@@ -145,7 +147,6 @@ std::vector<PchTaskQueue::Task> PchTaskQueue::createProjectTasks(PchTasks &&pchT
     auto convert = [this](auto &&pchTask) {
         return [pchTask = std::move(pchTask), this](PchCreatorInterface &pchCreator) mutable {
             const auto projectPartId = pchTask.projectPartId();
-            if (pchTask.includes.size()) {
                 pchTask.systemPchPath = m_precompiledHeaderStorage.fetchSystemPrecompiledHeaderPath(
                     projectPartId);
                 pchTask.preIncludeSearchPath = m_environment.preIncludeSearchPath();
@@ -157,9 +158,6 @@ std::vector<PchTaskQueue::Task> PchTaskQueue::createProjectTasks(PchTasks &&pchT
                     m_precompiledHeaderStorage.insertProjectPrecompiledHeader(
                         projectPartId, projectPartPch.pchPath, projectPartPch.lastModified);
                 }
-            } else {
-                m_precompiledHeaderStorage.deleteProjectPrecompiledHeader(projectPartId);
-            }
         };
     };
 
@@ -179,7 +177,6 @@ std::vector<PchTaskQueue::Task> PchTaskQueue::createSystemTasks(PchTasks &&pchTa
     auto convert = [this](auto &&pchTask) {
         return [pchTask = std::move(pchTask), this](PchCreatorInterface &pchCreator) mutable {
             const auto projectPartIds = pchTask.projectPartIds;
-            if (pchTask.includes.size()) {
                 pchTask.preIncludeSearchPath = m_environment.preIncludeSearchPath();
                 pchCreator.generatePch(std::move(pchTask));
                 const auto &projectPartPch = pchCreator.projectPartPch();
@@ -189,9 +186,6 @@ std::vector<PchTaskQueue::Task> PchTaskQueue::createSystemTasks(PchTasks &&pchTa
                     m_precompiledHeaderStorage.insertSystemPrecompiledHeaders(
                         projectPartIds, projectPartPch.pchPath, projectPartPch.lastModified);
                 }
-            } else {
-                m_precompiledHeaderStorage.deleteSystemPrecompiledHeaders(projectPartIds);
-            }
         };
     };
 
diff --git a/tests/unit/unittest/pchcreator-test.cpp b/tests/unit/unittest/pchcreator-test.cpp
index 66943fc147..0cf84a983d 100644
--- a/tests/unit/unittest/pchcreator-test.cpp
+++ b/tests/unit/unittest/pchcreator-test.cpp
@@ -315,6 +315,36 @@ TEST_F(PchCreatorVerySlowTest, FaultyProjectPartPchForCreatesFaultyPchForPchTask
                       Field(&ProjectPartPch::lastModified, Gt(0))));
 }
 
+TEST_F(PchCreatorSlowTest, NoIncludes)
+{
+    pchTask1.includes = {};
+
+    creator.generatePch(std::move(pchTask1));
+
+    ASSERT_THAT(creator.projectPartPch(),
+                AllOf(Field(&ProjectPartPch::projectPartId, Eq(pchTask1.projectPartId())),
+                      Field(&ProjectPartPch::pchPath, IsEmpty()),
+                      Field(&ProjectPartPch::lastModified, Gt(0))));
+}
+
+TEST_F(PchCreatorSlowTest, NoIncludesInTheMainThreadCalls)
+{
+    pchTask1.includes = {};
+    creator.generatePch(std::move(pchTask1));
+
+    EXPECT_CALL(mockPchManagerClient,
+                precompiledHeadersUpdated(
+                    Field(&ClangBackEnd::PrecompiledHeadersUpdatedMessage::projectPartIds,
+                          ElementsAre(Eq(creator.projectPartPch().projectPartId)))));
+    EXPECT_CALL(mockClangPathWatcher,
+                updateIdPaths(
+                    ElementsAre(AllOf(Field(&ClangBackEnd::IdPaths::id, 1),
+                                      Field(&ClangBackEnd::IdPaths::filePathIds, IsEmpty())))));
+    EXPECT_CALL(mockBuildDependenciesStorage, updatePchCreationTimeStamp(Gt(0), Eq(1)));
+
+    creator.doInMainThreadAfterFinished();
+}
+
 TEST_F(PchCreatorVerySlowTest, GeneratedFile)
 {
     creator.clear();