ProjectExplorer: Handle registering of auto-created bundle toolchains

... in the bundle itself, whenever possible.
It's very annoying to have to add this stanza in all places where
bundling takes place, and it's also easily forgotten, introducing memory
leaks.
This also nicely self-documents the expectations of the calling code as
to whether new toolchains can or cannot be created in the given context
as a side effect of bundling.

Change-Id: I78d2d4cdfc1010568f61f201b0d930b01f79a88b
Reviewed-by: hjk <hjk@qt.io>

src/plugins/projectexplorer/toolchain.cpp

@@ -879,7 +879,8 @@ void AsyncToolchainDetector::run()
  *   - There is exactly one toolchain in the list for every language supported by the factory.
  *   - If there is a C compiler, it comes first in the list.
  */
-ToolchainBundle::ToolchainBundle(const Toolchains &toolchains) : m_toolchains(toolchains)
+ToolchainBundle::ToolchainBundle(const Toolchains &toolchains, AutoRegister autoRegister)
+    : m_toolchains(toolchains)
 {
     // Check pre-conditions.
     QTC_ASSERT(!m_toolchains.isEmpty(), return);
@@ -892,7 +893,7 @@ ToolchainBundle::ToolchainBundle(const Toolchains &toolchains) : m_toolchains(to
         QTC_ASSERT(tc->bundleId() == toolchains.first()->bundleId(), return);
     }
 
-    addMissingToolchains();
+    addMissingToolchains(autoRegister);
 
     // Check post-conditions.
     QTC_ASSERT(m_toolchains.size() == m_toolchains.first()->factory()->supportedLanguages().size(),
@@ -905,12 +906,13 @@ ToolchainBundle::ToolchainBundle(const Toolchains &toolchains) : m_toolchains(to
     });
 }
 
-QList<ToolchainBundle> ToolchainBundle::collectBundles()
+QList<ToolchainBundle> ToolchainBundle::collectBundles(AutoRegister autoRegister)
 {
-    return collectBundles(ToolchainManager::toolchains());
+    return collectBundles(ToolchainManager::toolchains(), autoRegister);
 }
 
-QList<ToolchainBundle> ToolchainBundle::collectBundles(const Toolchains &toolchains)
+QList<ToolchainBundle> ToolchainBundle::collectBundles(
+    const Toolchains &toolchains, AutoRegister autoRegister)
 {
     QHash<Id, Toolchains> toolchainsPerBundleId;
     for (Toolchain * const tc : toolchains)
@@ -919,12 +921,12 @@ QList<ToolchainBundle> ToolchainBundle::collectBundles(const Toolchains &toolcha
     QList<ToolchainBundle> bundles;
     if (const auto unbundled = toolchainsPerBundleId.constFind(Id());
         unbundled != toolchainsPerBundleId.constEnd()) {
-        bundles = bundleUnbundledToolchains(*unbundled);
+        bundles = bundleUnbundledToolchains(*unbundled, autoRegister);
         toolchainsPerBundleId.erase(unbundled);
     }
 
     for (const Toolchains &tcs : toolchainsPerBundleId)
-        bundles << tcs;
+        bundles.emplaceBack(tcs, autoRegister);
     return bundles;
 }
 
@@ -971,7 +973,8 @@ ToolchainBundle::Valid ToolchainBundle::validity() const
     return Valid::None;
 }
 
-QList<ToolchainBundle> ToolchainBundle::bundleUnbundledToolchains(const Toolchains &unbundled)
+QList<ToolchainBundle> ToolchainBundle::bundleUnbundledToolchains(
+    const Toolchains &unbundled, AutoRegister autoRegister)
 {
     QList<ToolchainBundle> bundles;
     QHash<Id, QHash<Id, Toolchains>> unbundledByTypeAndLanguage;
@@ -997,7 +1000,7 @@ QList<ToolchainBundle> ToolchainBundle::bundleUnbundledToolchains(const Toolchai
             const Id newBundleId = Id::generate();
             for (Toolchain * const tc : nextBundle)
                 tc->setBundleId(newBundleId);
-            bundles << nextBundle;
+            bundles.emplaceBack(nextBundle, autoRegister);
         }
     }
 
@@ -1035,10 +1038,10 @@ ToolchainBundle ToolchainBundle::clone() const
     const Id newBundleId = Id::generate();
     for (Toolchain * const tc : clones)
         tc->setBundleId(newBundleId);
-    return clones;
+    return ToolchainBundle(clones, ToolchainBundle::AutoRegister::NotApplicable);
 }
 
-void ToolchainBundle::addMissingToolchains()
+void ToolchainBundle::addMissingToolchains(AutoRegister autoRegister)
 {
     const QList<Id> missingLanguages
         = Utils::filtered(m_toolchains.first()->factory()->supportedLanguages(), [this](Id lang) {
@@ -1046,12 +1049,23 @@ void ToolchainBundle::addMissingToolchains()
                   return tc->language() == lang;
               });
           });
+    Toolchains createdToolchains;
     for (const Id lang : missingLanguages) {
         Toolchain * const tc = m_toolchains.first()->clone();
         tc->setLanguage(lang);
         tc->setCompilerCommand(m_toolchains.first()->correspondingCompilerCommand(lang));
         m_toolchains << tc;
-        m_createdToolchains << tc;
+        createdToolchains << tc;
+    }
+
+    switch (autoRegister) {
+    case AutoRegister::On:
+        ToolchainManager::registerToolchains(createdToolchains);
+    case AutoRegister::Off:
+        break;
+    case AutoRegister::NotApplicable:
+        QTC_CHECK(createdToolchains.isEmpty());
+        break;
     }
 }