Completion in commit window improved (IDEA-CR-50723)

1. Return lookup elements in pure function way
2. TopLevelCompletionContributor renamed to SymbolNameCompletionContributor
3. Added support for Groovy

GitOrigin-RevId: 9428d52da9e22aaeb507afa1d86b6704116311c0

java/java-impl/src/META-INF/JavaPlugin.xml

@@ -1221,7 +1221,7 @@
     <completion.confidence language="JAVA" implementationClass="com.intellij.codeInsight.completion.JavadocCompletionConfidence" id="javadoc" order="before javaComments"/>
     <completion.confidence language="JAVA" implementationClass="com.intellij.codeInsight.completion.SkipAutopopupInComments" id="javaComments"/>
     <completion.confidence language="JAVA" implementationClass="com.intellij.codeInsight.completion.SkipAutopopupInStrings" id="javaSkipAutopopupInStrings"/>
-    <completion.toplevel language="JAVA" implementationClass="com.intellij.codeInsight.completion.JavaTopLevelCompletionContributor"/>
+    <completion.toplevel language="JAVA" implementationClass="com.intellij.codeInsight.completion.JavaSymbolNameCompletionContributor"/>
     <lookup.actionProvider implementation="com.intellij.codeInsight.completion.ExcludeFromCompletionLookupActionProvider" id="excludeFromCompletion" order="last"/>
     <lookup.actionProvider implementation="com.intellij.codeInsight.completion.ImportStaticLookupActionProvider" id="importStatic"/>
     <fileTypeFactory implementation="com.intellij.openapi.fileTypes.impl.JavaFileTypeFactory"/>

java/java-impl/src/com/intellij/codeInsight/completion/JavaSymbolNameCompletionContributor.java

@@ -0,0 +1,70 @@
+// Copyright 2000-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.intellij.codeInsight.completion;
+
+import com.intellij.codeInsight.lookup.LookupElement;
+import com.intellij.codeInsight.lookup.LookupElementBuilder;
+import com.intellij.psi.*;
+import com.intellij.util.ObjectUtils;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import javax.swing.*;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+
+public class JavaSymbolNameCompletionContributor implements SymbolNameCompletionContributor {
+  @NotNull
+  @Override
+  public Collection<LookupElement> getLookupElements(@NotNull PsiFile file, int invocationCount, @NotNull String prefix) {
+    PsiClassOwner javaFile = ObjectUtils.tryCast(file, PsiClassOwner.class);
+    if (javaFile == null) return Collections.emptyList();
+    List<LookupElement> result = new ArrayList<>();
+    for (PsiClass aClass : javaFile.getClasses()) {
+      String name = aClass.getName();
+      if (name != null) {
+        result.add(LookupElementBuilder.create(name).withIcon(aClass.getIcon(0)));
+        String infix = getInfix(prefix, name);
+        String memberPrefix = null;
+        if (infix != null) {
+          memberPrefix = prefix.substring(0, name.length() + infix.length());
+        }
+        else if (invocationCount <= 0) continue;
+        processClassBody(invocationCount, result, aClass, infix, memberPrefix);
+      }
+    }
+    return result;
+  }
+
+  protected void processClassBody(int invocationCount, List<LookupElement> result, PsiElement aClass, String infix, String memberPrefix) {
+    for (PsiElement child = aClass.getFirstChild(); child != null; child = child.getNextSibling()) {
+      if (child instanceof PsiField || child instanceof PsiMethod || child instanceof PsiClass) {
+        String memberName = ((PsiMember)child).getName();
+        Icon icon = child.getIcon(0);
+        if (memberName != null) {
+          LookupElementBuilder element = LookupElementBuilder.create(memberName).withIcon(icon);
+          if (invocationCount > 0) {
+            result.add(element);
+          }
+          if (memberPrefix != null) {
+            if (child instanceof PsiMethod || child instanceof PsiField && !infix.equals("::") || infix.equals(".")) {
+              result.add(LookupElementBuilder.create(memberPrefix + memberName).withIcon(icon));
+            }
+          }
+        }
+      }
+    }
+  }
+
+  @Nullable
+  private static String getInfix(String currentPrefix, String className) {
+    if (!currentPrefix.startsWith(className)) return null;
+    for (String infix : new String[]{".", "#", "::"}) {
+      if (currentPrefix.startsWith(infix, className.length())) {
+        return infix;
+      }
+    }
+    return null;
+  }
+}

java/java-impl/src/com/intellij/codeInsight/completion/JavaTopLevelCompletionContributor.java

@@ -1,62 +0,0 @@
-// Copyright 2000-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
-package com.intellij.codeInsight.completion;
-
-import com.intellij.codeInsight.lookup.LookupElementBuilder;
-import com.intellij.psi.*;
-import com.intellij.util.ObjectUtils;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
-
-import javax.swing.*;
-
-public class JavaTopLevelCompletionContributor implements TopLevelCompletionContributor {
-  @Override
-  public void addLookupElements(@NotNull PsiFile file, int invocationCount, @NotNull CompletionResultSet result) {
-    PsiJavaFile javaFile = ObjectUtils.tryCast(file, PsiJavaFile.class);
-    if (javaFile == null) return;
-    PrefixMatcher currentMatcher = result.getPrefixMatcher();
-    for (PsiClass aClass : javaFile.getClasses()) {
-      String name = aClass.getName();
-      if (name != null) {
-        result.addElement(LookupElementBuilder.create(name).withIcon(aClass.getIcon(0)));
-        String infix = getInfix(currentMatcher.getPrefix(), name);
-        CompletionResultSet prefixed = null;
-        if (infix == null) {
-          if (invocationCount <= 0) continue;
-        }
-        else {
-          String memberPrefix = currentMatcher.getPrefix().substring(name.length() + infix.length());
-          prefixed = result.withPrefixMatcher(currentMatcher.cloneWithPrefix(memberPrefix));
-        }
-        for (PsiElement child = aClass.getFirstChild(); child != null; child = child.getNextSibling()) {
-          if (child instanceof PsiField || child instanceof PsiMethod || child instanceof PsiClass) {
-            String memberName = ((PsiMember)child).getName();
-            Icon icon = child.getIcon(0);
-            if (memberName != null) {
-              LookupElementBuilder element = LookupElementBuilder.create(memberName).withIcon(icon);
-              if (invocationCount > 0) {
-                result.addElement(element);
-              }
-              if (prefixed != null) {
-                if (child instanceof PsiMethod || child instanceof PsiField && !infix.equals("::") || infix.equals(".")) {
-                  prefixed.addElement(element);
-                }
-              }
-            }
-          }
-        }
-      }
-    }
-  }
-
-  @Nullable
-  private static String getInfix(String currentPrefix, String className) {
-    if (!currentPrefix.startsWith(className)) return null;
-    for (String infix : new String[]{".", "#", "::"}) {
-      if (currentPrefix.startsWith(infix, className.length())) {
-        return infix;
-      }
-    }
-    return null;
-  }
-}

java/java-tests/testSrc/com/intellij/java/codeInsight/completion/JavaSymbolNameCompletionContributorTest.java

@@ -1,19 +1,20 @@
 // Copyright 2000-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.java.codeInsight.completion;
 
-import com.intellij.codeInsight.completion.CompletionResultSet;
-import com.intellij.codeInsight.completion.TopLevelCompletionContributor;
-import com.intellij.codeInsight.completion.TopLevelCompletionContributorEP;
-import com.intellij.codeInsight.completion.impl.CompletionServiceImpl;
+import com.intellij.codeInsight.completion.PlainPrefixMatcher;
+import com.intellij.codeInsight.completion.PrefixMatcher;
+import com.intellij.codeInsight.completion.SymbolNameCompletionContributor;
+import com.intellij.codeInsight.completion.SymbolNameCompletionContributorEP;
+import com.intellij.codeInsight.lookup.LookupElement;
 import com.intellij.lang.java.JavaLanguage;
 import com.intellij.psi.PsiFile;
 import com.intellij.testFramework.fixtures.LightJavaCodeInsightFixtureTestCase;
+import one.util.streamex.StreamEx;
 
-import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.List;
+import java.util.Collection;
 
-public class JavaTopLevelCompletionContributorTest extends LightJavaCodeInsightFixtureTestCase {
+public class JavaSymbolNameCompletionContributorTest extends LightJavaCodeInsightFixtureTestCase {
   public void testBasics() {
     PsiFile file = myFixture.configureByText("Test.java", "class Foo {\n" +
                                                           "  void fooMethod() {}\n" +
@@ -25,20 +26,18 @@ public class JavaTopLevelCompletionContributorTest extends LightJavaCodeInsightF
                                                           "}");
     checkCompletion(file, "", 0, "Foo", "Bar");
     checkCompletion(file, "F", 1, "Foo", "fooMethod", "fooField", "FooClass");
-    checkCompletion(file, "Foo::", 0, "fooMethod");
-    checkCompletion(file, "Foo#", 0, "fooMethod", "fooField");
-    checkCompletion(file, "Foo.", 0, "fooMethod", "fooField", "FooClass");
+    checkCompletion(file, "Foo::", 0, "Foo::fooMethod");
+    checkCompletion(file, "Foo#", 0, "Foo#fooMethod", "Foo#fooField");
+    checkCompletion(file, "Foo.", 0, "Foo.fooMethod", "Foo.fooField", "Foo.FooClass");
     checkCompletion(file, "B", 1, "Bar", "Baz");
   }
 
   private static void checkCompletion(PsiFile file, String prefix, int invocationCount, String... expected) {
-    TopLevelCompletionContributor contributor = TopLevelCompletionContributorEP.forLanguage(JavaLanguage.INSTANCE);
+    SymbolNameCompletionContributor contributor = SymbolNameCompletionContributorEP.forLanguage(JavaLanguage.INSTANCE);
     assertNotNull(contributor);
-    List<String> options = new ArrayList<>();
-    CompletionResultSet resultSet = CompletionServiceImpl.createResultSetForTest(
-      option -> options.add(option.getLookupElement().getLookupString()));
-    resultSet = resultSet.withPrefixMatcher(prefix);
-    contributor.addLookupElements(file, invocationCount, resultSet);
-    assertEquals(Arrays.asList(expected), options);
+    Collection<LookupElement> options = contributor.getLookupElements(file, invocationCount, prefix);
+    PrefixMatcher matcher = new PlainPrefixMatcher(prefix);
+    assertEquals(Arrays.asList(expected),
+                 StreamEx.of(options).filter(matcher::prefixMatches).map(LookupElement::getLookupString).toList());
   }
 }

platform/lang-api/src/com/intellij/codeInsight/completion/SymbolNameCompletionContributor.java

@@ -1,23 +1,29 @@
 // Copyright 2000-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.codeInsight.completion;
 
+import com.intellij.codeInsight.lookup.LookupElement;
 import com.intellij.psi.PsiFile;
 import org.jetbrains.annotations.NotNull;
 
+import java.util.Collection;
+
 /**
  * A language-specific completion contributor which provides reasonable amount of symbols declared in given file
  * (likely only top-level declarations). Such contributor could be used in plain text editors like VCS commit message field
  * to help users referring to code symbols from the text.
  *
- * @see TopLevelCompletionContributorEP
+ * @see SymbolNameCompletionContributorEP
  */
-public interface TopLevelCompletionContributor {
+public interface SymbolNameCompletionContributor {
   /**
    * Adds lookup elements from given file.
    *
    * @param file file to add elements from.
    * @param invocationCount number of times the completion was invoked (see {@link CompletionParameters#getInvocationCount()}).
-   * @param result a result object to add elements to (could be already prefixed with current context).
+   * @param prefix a prefix string. It's not required to return only matches starting with prefix, but this may be used to improve
+   *               performance.
+   * @return a collection of {@link LookupElement}'s to suggest.
    */
-  void addLookupElements(@NotNull PsiFile file, int invocationCount, @NotNull CompletionResultSet result);
+  @NotNull
+  Collection<LookupElement> getLookupElements(@NotNull PsiFile file, int invocationCount, @NotNull String prefix);
 }

platform/lang-api/src/com/intellij/codeInsight/completion/SymbolNameCompletionContributorEP.java

@@ -0,0 +1,17 @@
+// Copyright 2000-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.intellij.codeInsight.completion;
+
+import com.intellij.lang.Language;
+import com.intellij.lang.LanguageExtension;
+import com.intellij.lang.LanguageExtensionPoint;
+import com.intellij.openapi.extensions.ExtensionPointName;
+import org.jetbrains.annotations.NotNull;
+
+public class SymbolNameCompletionContributorEP extends LanguageExtensionPoint<SymbolNameCompletionContributor> {
+  private static final ExtensionPointName<SymbolNameCompletionContributorEP> EP = new ExtensionPointName<>("com.intellij.completion.toplevel");
+  private static final LanguageExtension<SymbolNameCompletionContributor> INSTANCE = new CompletionExtension<>(EP.getName());
+
+  public static SymbolNameCompletionContributor forLanguage(@NotNull Language language) {
+    return INSTANCE.forLanguage(language);
+  }
+}

platform/lang-api/src/com/intellij/codeInsight/completion/TopLevelCompletionContributorEP.java

@@ -1,17 +0,0 @@
-// Copyright 2000-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
-package com.intellij.codeInsight.completion;
-
-import com.intellij.lang.Language;
-import com.intellij.lang.LanguageExtension;
-import com.intellij.lang.LanguageExtensionPoint;
-import com.intellij.openapi.extensions.ExtensionPointName;
-import org.jetbrains.annotations.NotNull;
-
-public class TopLevelCompletionContributorEP extends LanguageExtensionPoint<TopLevelCompletionContributor> {
-  private static final ExtensionPointName<TopLevelCompletionContributorEP> EP = new ExtensionPointName<>("com.intellij.completion.toplevel");
-  private static final LanguageExtension<TopLevelCompletionContributor> INSTANCE = new CompletionExtension<>(EP.getName());
-
-  public static TopLevelCompletionContributor forLanguage(@NotNull Language language) {
-    return INSTANCE.forLanguage(language);
-  }
-}

platform/lang-impl/src/com/intellij/codeInsight/completion/impl/CompletionServiceImpl.java

@@ -20,7 +20,6 @@ import com.intellij.util.Consumer;
 import com.intellij.util.ExceptionUtil;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
-import org.jetbrains.annotations.TestOnly;
 
 import java.util.ArrayList;
 
@@ -101,11 +100,6 @@ public final class CompletionServiceImpl extends CompletionService {
     return new CompletionResultSetImpl(consumer, matcher, contributor, parameters, defaultSorter(parameters, matcher), null);
   }
 
-  @TestOnly
-  public static CompletionResultSet createResultSetForTest(Consumer<? super CompletionResult> consumer) {
-    return new CompletionResultSetImpl(consumer, PrefixMatcher.ALWAYS_TRUE, null, null, new CompletionSorterImpl(new ArrayList<>()), null);
-  }
-
   @Override
   public CompletionProcess getCurrentCompletion() {
     CompletionProgressIndicator indicator = getCurrentCompletionProgressIndicator();

platform/platform-resources/src/META-INF/LangExtensionPoints.xml

@@ -545,8 +545,8 @@
       <with attribute="implementationClass" implements="com.intellij.codeInsight.completion.CompletionConfidence"/>
     </extensionPoint>
 
-    <extensionPoint name="completion.toplevel" beanClass="com.intellij.codeInsight.completion.TopLevelCompletionContributorEP">
-      <with attribute="implementationClass" implements="com.intellij.codeInsight.completion.TopLevelCompletionContributor"/>
+    <extensionPoint name="completion.toplevel" beanClass="com.intellij.codeInsight.completion.SymbolNameCompletionContributorEP">
+      <with attribute="implementationClass" implements="com.intellij.codeInsight.completion.SymbolNameCompletionContributor"/>
     </extensionPoint>
 
     <extensionPoint name="completion.preselectionBehaviourProvider"

platform/vcs-impl/src/com/intellij/openapi/vcs/CommitCompletionContributor.java

@@ -80,8 +80,8 @@ public class CommitCompletionContributor extends CompletionContributor {
     if (vFile == null) return;
     PsiFile psiFile = PsiManagerEx.getInstanceEx(project).findFile(vFile);
     if (psiFile == null) return;
-    TopLevelCompletionContributor contributor = TopLevelCompletionContributorEP.forLanguage(psiFile.getLanguage());
+    SymbolNameCompletionContributor contributor = SymbolNameCompletionContributorEP.forLanguage(psiFile.getLanguage());
     if (contributor == null) return;
-    contributor.addLookupElements(psiFile, count, prefixed);
+    prefixed.addAllElements(contributor.getLookupElements(psiFile, count, prefixed.getPrefixMatcher().getPrefix()));
   }
 }

plugins/groovy/src/META-INF/plugin.xml

@@ -514,6 +514,7 @@
     <codeInsight.gotoSuper language="Groovy"
                            implementationClass="org.jetbrains.plugins.groovy.codeInsight.navigation.actions.GroovyGotoSuperHandler"/>
     <lookup.charFilter implementation="org.jetbrains.plugins.groovy.lang.completion.GroovyReferenceCharFilter"/>
+    <completion.toplevel language="Groovy" implementationClass="org.jetbrains.plugins.groovy.lang.completion.GroovySymbolNameCompletionContributor"/>
     <completion.contributor language="Groovy" implementationClass="org.jetbrains.plugins.groovy.lang.completion.GroovyNoVariantsDelegator"
                             id="groovyBasic2ClassName" order="first, after liveTemplates"/>
     <completion.contributor language="Groovy" implementationClass="org.jetbrains.plugins.groovy.lang.completion.GroovyCompletionContributor"

plugins/groovy/src/org/jetbrains/plugins/groovy/lang/completion/GroovySymbolNameCompletionContributor.java

@@ -0,0 +1,42 @@
+// Copyright 2000-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package org.jetbrains.plugins.groovy.lang.completion;
+
+import com.intellij.codeInsight.completion.JavaSymbolNameCompletionContributor;
+import com.intellij.codeInsight.lookup.LookupElement;
+import com.intellij.codeInsight.lookup.LookupElementBuilder;
+import com.intellij.psi.PsiElement;
+import com.intellij.psi.PsiFile;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.plugins.groovy.lang.psi.GroovyFile;
+import org.jetbrains.plugins.groovy.lang.psi.api.statements.typedef.GrTypeDefinition;
+import org.jetbrains.plugins.groovy.lang.psi.api.statements.typedef.GrTypeDefinitionBody;
+import org.jetbrains.plugins.groovy.lang.psi.api.statements.typedef.members.GrMethod;
+
+import java.util.Collection;
+import java.util.List;
+
+public class GroovySymbolNameCompletionContributor extends JavaSymbolNameCompletionContributor {
+  @NotNull
+  @Override
+  public Collection<LookupElement> getLookupElements(@NotNull PsiFile file, int invocationCount, @NotNull String prefix) {
+    Collection<LookupElement> elements = super.getLookupElements(file, invocationCount, prefix);
+    if (file instanceof GroovyFile) {
+      GrMethod[] methods = ((GroovyFile)file).getMethods();
+      for (GrMethod method : methods) {
+        elements.add(LookupElementBuilder.create(method.getName())
+                       .withTailText(" in "+file.getName(), true).withIcon(method.getIcon(0)));
+      }
+    }
+    return elements;
+  }
+
+  @Override
+  protected void processClassBody(int invocationCount, List<LookupElement> result, PsiElement aClass, String infix, String memberPrefix) {
+    if (aClass instanceof GrTypeDefinition) {
+      GrTypeDefinitionBody body = ((GrTypeDefinition)aClass).getBody();
+      if (body != null) {
+        super.processClassBody(invocationCount, result, body, infix, memberPrefix);
+      }
+    }
+  }
+}