Added line marker and goto related item provider for *.py to *.pyi (PY-16402)

python/src/META-INF/python-core.xml

@@ -562,6 +562,7 @@
     <multiHostInjector implementation="com.jetbrains.python.codeInsight.PyTypingAnnotationInjector"/>
     <lang.parserDefinition language="PythonStub" implementationClass="com.jetbrains.python.pyi.PyiParserDefinition"/>
     <fileTypeFactory implementation="com.jetbrains.python.pyi.PyiFileTypeFactory"/>
+    <codeInsight.lineMarkerProvider language="Python" implementationClass="com.jetbrains.python.pyi.PyiRelatedItemLineMarkerProvider"/>
 
     <lang.inspectionSuppressor language="Python" implementationClass="com.jetbrains.python.inspections.PyInspectionsSuppressor"/>
   </extensions>

python/src/com/jetbrains/python/pyi/PyiRelatedItemLineMarkerProvider.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.jetbrains.python.pyi;
+
+import com.intellij.codeHighlighting.Pass;
+import com.intellij.codeInsight.daemon.GutterIconNavigationHandler;
+import com.intellij.codeInsight.daemon.RelatedItemLineMarkerInfo;
+import com.intellij.codeInsight.daemon.RelatedItemLineMarkerProvider;
+import com.intellij.icons.AllIcons;
+import com.intellij.navigation.GotoRelatedItem;
+import com.intellij.openapi.editor.markup.GutterIconRenderer;
+import com.intellij.psi.PsiElement;
+import com.intellij.util.Function;
+import com.intellij.util.PsiNavigateUtil;
+import com.jetbrains.python.psi.PyElement;
+import com.jetbrains.python.psi.PyFunction;
+import com.jetbrains.python.psi.PyTargetExpression;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import javax.swing.*;
+import java.awt.event.MouseEvent;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+
+/**
+ * @author vlan
+ */
+public class PyiRelatedItemLineMarkerProvider extends RelatedItemLineMarkerProvider {
+  // TODO: Create an icon for a related Python stub item
+  public static final Icon ICON = AllIcons.Gutter.Unique;
+
+  @Override
+  protected void collectNavigationMarkers(@NotNull PsiElement element, Collection<? super RelatedItemLineMarkerInfo> result) {
+    final PsiElement pythonStub = getPythonStub(element);
+    if (pythonStub != null) {
+      final List<GotoRelatedItem> relatedItems = GotoRelatedItem.createItems(Collections.singletonList(pythonStub));
+      result.add(new RelatedItemLineMarkerInfo<PsiElement>(
+        element, element.getTextRange(), ICON, Pass.UPDATE_OVERRIDEN_MARKERS,
+        new Function<PsiElement, String>() {
+          @Override
+          public String fun(PsiElement element) {
+            return "Has stub item in " + pythonStub.getContainingFile().getName();
+          }
+        }, new GutterIconNavigationHandler<PsiElement>() {
+          @Override
+          public void navigate(MouseEvent e, PsiElement elt) {
+            final PsiElement pythonStub = getPythonStub(elt);
+            if (pythonStub != null) {
+              PsiNavigateUtil.navigate(pythonStub);
+            }
+          }
+        }, GutterIconRenderer.Alignment.RIGHT, relatedItems));
+    }
+  }
+
+  @Nullable
+  private static PsiElement getPythonStub(@NotNull PsiElement element) {
+    if (element instanceof PyFunction || element instanceof PyTargetExpression) {
+      return PyiUtil.getPythonStub((PyElement)element);
+    }
+    return null;
+  }
+}