PY-47962 Put non-imported module names last among completion variants

By giving them an explicit priority lower than the default. Unfortunately,
it doesn't remedy the problem with short module names, such as "re" or "sys",
always being on top when they completely match the entered prefix.
At the moment this behavior is hard-coded in the platform and cannot be
altered by language plugins. It's not caused by the "liftShorter" classifier.

Also, explicitly prioritizing various lookup elements has become quite messy
and scattered across PyCompletionWeigher and specific contributors. It begs
to be refactored, but will be addressed separately.

GitOrigin-RevId: d6f6ad06f5d68f3de7b866b8240a95b785604649

python/python-psi-impl/src/com/jetbrains/python/codeInsight/completion/PyModuleNameCompletionContributor.kt

@@ -4,6 +4,7 @@ package com.jetbrains.python.codeInsight.completion
 import com.intellij.codeInsight.completion.CompletionContributor
 import com.intellij.codeInsight.completion.CompletionParameters
 import com.intellij.codeInsight.completion.CompletionResultSet
+import com.intellij.codeInsight.completion.PrioritizedLookupElement
 import com.intellij.codeInsight.lookup.LookupElement
 import com.intellij.openapi.project.DumbAware
 import com.intellij.psi.MultiplePsiFilesPerDocumentFileViewProvider
@@ -14,6 +15,7 @@ import com.intellij.psi.util.QualifiedName
 import com.intellij.util.ProcessingContext
 import com.jetbrains.python.PyNames
 import com.jetbrains.python.PythonRuntimeService
+import com.jetbrains.python.codeInsight.completion.PythonCompletionWeigher.NOT_IMPORTED_MODULE_WEIGHT
 import com.jetbrains.python.psi.PyFile
 import com.jetbrains.python.psi.PyImportStatementBase
 import com.jetbrains.python.psi.PyReferenceExpression
@@ -54,7 +56,7 @@ class PyModuleNameCompletionContributor : CompletionContributor(), DumbAware {
     getCompletionVariants(parameters.position.parent, parameters.originalFile, otherVariants).asSequence()
       .filterIsInstance<LookupElement>()
       .filterNot { it.lookupString.startsWith('_') }
-      .forEach { result.addElement(it) }
+      .forEach { result.addElement(PrioritizedLookupElement.withPriority(it, NOT_IMPORTED_MODULE_WEIGHT.toDouble())) }
   }
 
   private fun getCompletionVariants(element: PsiElement, file: PsiElement, otherVariants: Set<String>): List<Any> {

python/python-psi-impl/src/com/jetbrains/python/codeInsight/completion/PythonCompletionWeigher.java

@@ -36,12 +36,14 @@ import org.jetbrains.annotations.NotNull;
  */
 public class PythonCompletionWeigher extends CompletionWeigher {
 
+  // TODO Unify different ways of detecting and weighing elements
   public static final int PRIORITY_WEIGHT = 5;
   public static final int WEIGHT_FOR_MULTIPLE_ARGUMENTS = 5;
   public static final int WEIGHT_FOR_KEYWORDS = 0;
   private static final Logger LOG = Logger.getInstance(PythonCompletionWeigher.class);
   public static final String COLLECTION_KEY = "dict key";
   private static final int COLLECTION_KEY_WEIGHT = 10;
+  public static final int NOT_IMPORTED_MODULE_WEIGHT = -1;
 
   @Override
   public Comparable weigh(@NotNull final LookupElement element, @NotNull final CompletionLocation location) {

python/testData/completion/notImportedQualifiedName/NonImportedModulesSuggestedLast/main.py

@@ -0,0 +1,4 @@
+def func(configuration=):
+    pass
+    
+func(con<caret>)

python/testSrc/com/jetbrains/python/PyNotImportedQualifiedNameCompletionTest.java

@@ -173,6 +173,13 @@ public class PyNotImportedQualifiedNameCompletionTest extends PyTestCase {
     assertEquals(1, ContainerUtil.count(variants, "foo"::equals));
   }
 
+  // PY-47962
+  public void testNonImportedModulesSuggestedLast() {
+    doBasicCompletion();
+    myFixture.assertPreferredCompletionItems(0, "configuration=");
+    assertContainsElements(myFixture.getLookupElementStrings(), "config", "contrib");
+  }
+
   @Nullable
   private List<String> doBasicCompletion() {
     myFixture.copyDirectoryToProject(getTestName(false), "");