From 2514a8b5156de85b61e5528c5c8a83b80a18ab4a Mon Sep 17 00:00:00 2001
From: Mikhail Golubev <mikhail.golubev@jetbrains.com>
Date: Wed, 5 Apr 2017 18:24:14 +0300
Subject: [PATCH] PY-23150 Show the canonized qualified name of a source module
 as type in completion

instead of the much more computationally expensive canonical import
name.

It still an open question, though, how to reduce the cost of computing
the preferred import path of re-exported symbols in case of a large
hierarchy of packages where names from the leaf modules are propagated
higher using wildcard imports.

Check https://github.com/JetBrains/intellij-community/pull/532
for the related dicussion.
---
 .../userSkeletons/PyUserSkeletonsUtil.java    |  9 +++------
 .../resolve/CompletionVariantsProcessor.java  | 10 ++++------
 .../psi/resolve/QualifiedNameFinder.java      | 19 +++++++++++++------
 3 files changed, 20 insertions(+), 18 deletions(-)

diff --git a/python/src/com/jetbrains/python/codeInsight/userSkeletons/PyUserSkeletonsUtil.java b/python/src/com/jetbrains/python/codeInsight/userSkeletons/PyUserSkeletonsUtil.java
index baf0bdfdbe2e..92630437d351 100644
--- a/python/src/com/jetbrains/python/codeInsight/userSkeletons/PyUserSkeletonsUtil.java
+++ b/python/src/com/jetbrains/python/codeInsight/userSkeletons/PyUserSkeletonsUtil.java
@@ -17,7 +17,6 @@ package com.jetbrains.python.codeInsight.userSkeletons;
 
 import com.intellij.openapi.application.PathManager;
 import com.intellij.openapi.diagnostic.Logger;
-import com.intellij.openapi.extensions.Extensions;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.projectRoots.Sdk;
 import com.intellij.openapi.util.Key;
@@ -198,11 +197,9 @@ public class PyUserSkeletonsUtil {
           return null;
         }
         final QualifiedName qName = QualifiedName.fromDottedString(moduleName);
-        for (PyCanonicalPathProvider provider : Extensions.getExtensions(PyCanonicalPathProvider.EP_NAME)) {
-          final QualifiedName restored = provider.getCanonicalPath(qName, null);
-          if (restored != null) {
-            moduleName = restored.toString();
-          }
+        final QualifiedName restored = QualifiedNameFinder.canonizeQualifiedName(qName, null);
+        if (restored != null) {
+          moduleName = restored.toString();
         }
         final PyFile skeletonFile = getUserSkeletonForModuleQName(moduleName, file);
         file.putUserData(HAS_SKELETON, skeletonFile != null);
diff --git a/python/src/com/jetbrains/python/psi/resolve/CompletionVariantsProcessor.java b/python/src/com/jetbrains/python/psi/resolve/CompletionVariantsProcessor.java
index 3f1653fc7774..df0944e8bb9e 100644
--- a/python/src/com/jetbrains/python/psi/resolve/CompletionVariantsProcessor.java
+++ b/python/src/com/jetbrains/python/psi/resolve/CompletionVariantsProcessor.java
@@ -23,7 +23,7 @@ import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.psi.PsiElement;
 import com.intellij.psi.util.PsiTreeUtil;
 import com.intellij.psi.util.QualifiedName;
-import com.intellij.util.Function;
+import com.intellij.util.ObjectUtils;
 import com.intellij.util.PlatformIcons;
 import com.jetbrains.python.PyNames;
 import com.jetbrains.python.codeInsight.completion.PyClassInsertHandler;
@@ -32,6 +32,7 @@ import com.jetbrains.python.codeInsight.controlflow.ScopeOwner;
 import com.jetbrains.python.codeInsight.dataflow.scope.ScopeUtil;
 import com.jetbrains.python.psi.*;
 import com.jetbrains.python.psi.impl.PyBuiltinCache;
+import com.jetbrains.python.psi.impl.PyPsiUtils;
 import com.jetbrains.python.psi.types.TypeEvalContext;
 import org.jetbrains.annotations.Nullable;
 
@@ -101,12 +102,9 @@ public class CompletionVariantsProcessor extends VariantsProcessor {
         source = cls.getName();
       }
       else if (myContext == null || !PyUtil.inSameFile(myContext, element)) {
-        QualifiedName path = QualifiedNameFinder.findCanonicalImportPath(element, null);
+        final QualifiedName path = QualifiedNameFinder.findShortestImportableQName(PyPsiUtils.getFileSystemItem(element));
         if (path != null) {
-          if (element instanceof PyFile) {
-            path = path.removeLastComponent();
-          }
-          source = path.toString();
+          source = ObjectUtils.chooseNotNull(QualifiedNameFinder.canonizeQualifiedName(path, null), path).toString();
         }
       }
     }
diff --git a/python/src/com/jetbrains/python/psi/resolve/QualifiedNameFinder.java b/python/src/com/jetbrains/python/psi/resolve/QualifiedNameFinder.java
index 3fc8cb5cbe3c..d7aa971e1d88 100644
--- a/python/src/com/jetbrains/python/psi/resolve/QualifiedNameFinder.java
+++ b/python/src/com/jetbrains/python/psi/resolve/QualifiedNameFinder.java
@@ -155,16 +155,23 @@ public class QualifiedNameFinder {
     }
     final QualifiedName qname = findShortestImportableQName(foothold != null ? foothold : symbol, virtualFile);
     if (qname != null) {
-      for (PyCanonicalPathProvider provider : Extensions.getExtensions(PyCanonicalPathProvider.EP_NAME)) {
-        final QualifiedName restored = provider.getCanonicalPath(qname, foothold);
-        if (restored != null) {
-          return restored;
-        }
-      }
+      final QualifiedName restored = canonizeQualifiedName(qname, foothold);
+      if (restored != null) return restored;
     }
     return qname;
   }
 
+  @Nullable
+  public static QualifiedName canonizeQualifiedName(QualifiedName qname, PsiElement foothold) {
+    for (PyCanonicalPathProvider provider : Extensions.getExtensions(PyCanonicalPathProvider.EP_NAME)) {
+      final QualifiedName restored = provider.getCanonicalPath(qname, foothold);
+      if (restored != null) {
+        return restored;
+      }
+    }
+    return null;
+  }
+
   @Nullable
   public static String getQualifiedName(@NotNull PyElement element) {
     final String name = element.getName();