From 039a34a369d96384cf72ae6979bff6f6fb36a0e7 Mon Sep 17 00:00:00 2001
From: Ivan Donchevskii <ivan.donchevskii@qt.io>
Date: Wed, 17 Oct 2018 14:16:32 +0200
Subject: [PATCH] Clang: Adapt priorities for the same method/constructor
 overloads

CXXMethod and CXXConstructor may have different priorities
depending ony their origin and attributes. To keep them together
in the sorted list we adapt their priorities to have the same
value if their names match.
To continue keeping ClassCompletion before ConstructorCompletion
change the order of the completion kinds for the sort purposes.

Change-Id: I36efe5d5dbaa77d604a54b1dafe07d67f44db4c9
Reviewed-by: Marco Bubke <marco.bubke@qt.io>
---
 src/libs/clangsupport/codecompletion.h        |  4 +-
 .../clangcompletionassistprocessor.cpp        |  3 +-
 .../source/codecompletionsextractor.cpp       | 47 ++++++++++---------
 3 files changed, 27 insertions(+), 27 deletions(-)

diff --git a/src/libs/clangsupport/codecompletion.h b/src/libs/clangsupport/codecompletion.h
index e3553f22a88..4a97fe08c15 100644
--- a/src/libs/clangsupport/codecompletion.h
+++ b/src/libs/clangsupport/codecompletion.h
@@ -42,16 +42,16 @@ using CodeCompletions = QVector<CodeCompletion>;
 class CodeCompletion
 {
 public:
-    enum Kind : quint32 {
+    enum Kind : uint8_t {
         Other = 0,
         FunctionCompletionKind,
         FunctionDefinitionCompletionKind,
         FunctionOverloadCompletionKind,
         TemplateFunctionCompletionKind,
+        ClassCompletionKind,
         ConstructorCompletionKind,
         DestructorCompletionKind,
         VariableCompletionKind,
-        ClassCompletionKind,
         TypeAliasCompletionKind,
         TemplateClassCompletionKind,
         EnumerationCompletionKind,
diff --git a/src/plugins/clangcodemodel/clangcompletionassistprocessor.cpp b/src/plugins/clangcodemodel/clangcompletionassistprocessor.cpp
index db68f680bc6..b16f458ca54 100644
--- a/src/plugins/clangcodemodel/clangcompletionassistprocessor.cpp
+++ b/src/plugins/clangcodemodel/clangcompletionassistprocessor.cpp
@@ -113,8 +113,7 @@ static bool isTheSameFunctionOverload(const CodeCompletion &completion,
                                       const QString &name,
                                       ClangAssistProposalItem *lastItem)
 {
-    return completion.hasParameters
-            && completion.completionKind == lastItem->firstCodeCompletion().completionKind
+    return completion.completionKind == lastItem->firstCodeCompletion().completionKind
             && lastItem->text() == name;
 }
 
diff --git a/src/tools/clangbackend/source/codecompletionsextractor.cpp b/src/tools/clangbackend/source/codecompletionsextractor.cpp
index 2e2817c72b7..f9c019b66d9 100644
--- a/src/tools/clangbackend/source/codecompletionsextractor.cpp
+++ b/src/tools/clangbackend/source/codecompletionsextractor.cpp
@@ -110,24 +110,30 @@ static CodeCompletions filterFunctionOverloads(const CodeCompletions &completion
     });
 }
 
-static ::Utils::optional<bool> classBeforeCXXConstructor(const CodeCompletion &first,
-                                                         const CodeCompletion &second)
+static void adaptOverloadsPriorities(CodeCompletions &codeCompletions)
 {
-    // Put ClassCompletionKind elements before ConstructorCompletionKind elements
-    // when they have the same name.
-    if (first.completionKind == CodeCompletion::ClassCompletionKind
-            && second.completionKind == CodeCompletion::ConstructorCompletionKind
-            && first.text == second.text) {
-        return true;
-    }
+    std::map<Utf8String, std::vector<CodeCompletion *>> cachedOverloads;
+    for (CodeCompletion &currentCompletion : codeCompletions) {
+        if (currentCompletion.completionKind != CodeCompletion::ConstructorCompletionKind
+                && currentCompletion.completionKind != CodeCompletion::FunctionCompletionKind) {
+            continue;
+        }
 
-    if (first.completionKind == CodeCompletion::ConstructorCompletionKind
-            && second.completionKind == CodeCompletion::ClassCompletionKind
-            && first.text == second.text) {
-        return false;
+        auto found = cachedOverloads.find(currentCompletion.text);
+        if (found == cachedOverloads.end()) {
+            cachedOverloads[currentCompletion.text].push_back(&currentCompletion);
+        } else {
+            const quint32 oldPriority = found->second.front()->priority;
+            if (currentCompletion.priority >= oldPriority) {
+                currentCompletion.priority = oldPriority;
+            } else {
+                const quint32 newPriority = currentCompletion.priority;
+                for (CodeCompletion *completion : found->second)
+                    completion->priority = newPriority;
+            }
+            found->second.push_back(&currentCompletion);
+        }
     }
-
-    return ::Utils::optional<bool>();
 }
 
 static void sortCodeCompletions(CodeCompletions &codeCompletions)
@@ -138,14 +144,8 @@ static void sortCodeCompletions(CodeCompletions &codeCompletions)
         if (first.requiredFixIts.empty() != second.requiredFixIts.empty())
             return first.requiredFixIts.empty() > second.requiredFixIts.empty();
 
-        const ::Utils::optional<bool> classBeforeConstructorWithTheSameName
-                = classBeforeCXXConstructor(first, second);
-        if (classBeforeConstructorWithTheSameName)
-            return classBeforeConstructorWithTheSameName.value();
-
-        return (first.priority > 0
-                && (first.priority < second.priority
-                    || (first.priority == second.priority && first.text < second.text)));
+        return std::tie(first.priority, first.text, first.completionKind)
+                < std::tie(second.priority, second.text, second.completionKind);
     };
 
     // Keep the order for the items with the same priority and name.
@@ -164,6 +164,7 @@ void CodeCompletionsExtractor::handleCompletions(CodeCompletions &codeCompletion
             codeCompletions = overloadCompletions;
     }
 
+    adaptOverloadsPriorities(codeCompletions);
     sortCodeCompletions(codeCompletions);
 }