Editor: reuse generic proposal widget

Do not close already visible proposal widget if we get new results for
the same base position. Just replace the model of the widget and update
the prefix.

Change-Id: I298aba6eb8177edc17fea783189a2f987dbf15a2
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

1 files changed, 17 insertions, 5 deletions

diff --git a/src/plugins/texteditor/codeassist/codeassistant.cpp b/src/plugins/texteditor/codeassist/codeassistant.cpp
index 3eecfa9530..bf1d2be10c 100644
--- a/src/plugins/texteditor/codeassist/codeassistant.cpp
+++ b/src/plugins/texteditor/codeassist/codeassistant.cpp
@@ -41,6 +41,7 @@
 #include <coreplugin/editormanager/editormanager.h>
 #include <extensionsystem/pluginmanager.h>
 #include <utils/algorithm.h>
+#include <utils/executeondestruction.h>
 #include <utils/qtcassert.h>
 
 #include <QKeyEvent>
@@ -157,7 +158,6 @@ void CodeAssistantPrivate::invoke(AssistKind kind, IAssistProvider *provider)
                         m_proposal->basePosition(),
                         m_editorWidget->position() - m_proposal->basePosition()));
     } else {
-        destroyContext();
         requestProposal(ExplicitlyInvoked, kind, provider);
     }
 }
@@ -166,8 +166,6 @@ bool CodeAssistantPrivate::requestActivationCharProposal()
 {
     if (m_assistKind == Completion && m_settings.m_completionTrigger != ManualCompletion) {
         if (CompletionAssistProvider *provider = identifyActivationSequence()) {
-            if (isWaitingForProposal())
-                cancelCurrentRequest();
             requestProposal(ActivationCharacter, Completion, provider);
             return true;
         }
@@ -194,7 +192,10 @@ void CodeAssistantPrivate::requestProposal(AssistReason reason,
                                            AssistKind kind,
                                            IAssistProvider *provider)
 {
-    QTC_ASSERT(!isWaitingForProposal(), return);
+    // make sure to cleanup old proposals if we cannot find a new assistant
+    Utils::ExecuteOnDestruction earlyReturnContextClear([this]() { destroyContext(); });
+    if (isWaitingForProposal())
+        cancelCurrentRequest();
 
     if (m_editorWidget->hasBlockSelection())
         return; // TODO
@@ -215,6 +216,9 @@ void CodeAssistantPrivate::requestProposal(AssistReason reason,
     if (!assistInterface)
         return;
 
+    // We got an assist provider and interface so no need to reset the current context anymore
+    earlyReturnContextClear.reset({});
+
     m_assistKind = kind;
     m_requestProvider = provider;
     IAssistProcessor *processor = provider->createProcessor();
@@ -337,6 +341,15 @@ void CodeAssistantPrivate::displayProposal(IAssistProposal *newProposal, AssistR
         return;
     }
 
+    if (m_proposalWidget
+        && basePosition == proposalCandidate->basePosition()
+        && m_proposalWidget->supportsModelUpdate(proposalCandidate->id())) {
+        m_proposal.reset(proposalCandidate.take());
+        m_proposalWidget->updateModel(m_proposal->model());
+        m_proposalWidget->updateProposal(prefix);
+        return;
+    }
+
     destroyContext();
 
     clearAbortedPosition();
@@ -471,7 +484,6 @@ void CodeAssistantPrivate::notifyChange()
             if (!isDisplayingProposal())
                 requestActivationCharProposal();
         } else {
-            destroyContext();
             requestProposal(ExplicitlyInvoked, m_assistKind, m_requestProvider);
         }
     }