Create Dart breadcrumb provider

Dart/resources/META-INF/plugin.xml

@@ -40,6 +40,8 @@
     <typedHandler implementation="com.jetbrains.lang.dart.ide.editor.DartTypeHandler" id="Dart"/>
     <quoteHandler fileType="Dart" className="com.jetbrains.lang.dart.ide.editor.DartQuoteHandler"/>
 
+    <breadcrumbsInfoProvider implementation="com.jetbrains.lang.dart.ide.breadcrumbs.DartBreadcrumbsInfoProvider"/>
+
     <lang.commenter language="Dart" implementationClass="com.jetbrains.lang.dart.ide.DartCommenter"/>
     <lang.parserDefinition language="Dart" implementationClass="com.jetbrains.lang.dart.DartParserDefinition"/>
 

Dart/src/com/jetbrains/lang/dart/ide/breadcrumbs/DartBreadcrumbsInfoProvider.kt

@@ -0,0 +1,165 @@
+// Copyright 2000-2022 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package com.jetbrains.lang.dart.ide.breadcrumbs
+
+import com.intellij.openapi.util.text.StringUtil
+import com.intellij.psi.PsiElement
+import com.intellij.psi.util.parents
+import com.intellij.ui.breadcrumbs.BreadcrumbsProvider
+import com.jetbrains.lang.dart.DartComponentType
+import com.jetbrains.lang.dart.DartLanguage
+import com.jetbrains.lang.dart.psi.*
+import javax.swing.Icon
+
+/**
+ * Generates breadcrumbs for the selected element in a Dart file.
+ */
+class DartBreadcrumbsInfoProvider : BreadcrumbsProvider {
+  override fun getLanguages() = arrayOf(DartLanguage.INSTANCE)
+
+  override fun acceptElement(element: PsiElement) = getHandler(element) != null
+
+  override fun getElementInfo(element: PsiElement): String =
+    getHandler(element)!!.getElementInfo(element as DartPsiCompositeElement)
+
+  override fun getElementIcon(element: PsiElement): Icon? =
+    getHandler(element)!!.getElementIcon(element as DartPsiCompositeElement)
+    ?: DartComponentType.typeOf(element)?.icon
+
+  /**
+   * Handles generating crumbs for elements it supports.
+   */
+  private abstract class ElementHandler<TElement : DartPsiCompositeElement>(val type: Class<TElement>) {
+    /** Whether this handler can generate a crumb for the specified element. */
+    open fun accepts(element: TElement): Boolean = true
+
+    /** The icon to display for some element. */
+    open fun getElementIcon(element: TElement): Icon? = null
+
+    /** A crumb for the specified element. */
+    abstract fun getElementInfo(element: TElement): String
+  }
+
+  @Suppress("UNCHECKED_CAST")
+  private fun getHandler(e: PsiElement): ElementHandler<in DartPsiCompositeElement>? {
+    if (e !is DartPsiCompositeElement) return null
+    val handler = Handlers.handlers.firstOrNull { it.type.isInstance(e) && (it as ElementHandler<in DartPsiCompositeElement>).accepts(e) }
+    return handler as ElementHandler<in DartPsiCompositeElement>?
+  }
+
+  /**
+   * Element handlers to use when generating crumbs.
+   */
+  private object Handlers {
+    val handlers: List<ElementHandler<*>> = listOf<ElementHandler<*>>(
+      ConstructorHandler,
+      NonLocalVariableHandler,
+      NamedTypeHandler,
+      UnitTestHandler,
+    )
+  }
+
+  /**
+   * Generates crumbs for constructor invocations.
+   */
+  private object ConstructorHandler : ElementHandler<DartCallExpression>(DartCallExpression::class.java) {
+    override fun accepts(element: DartCallExpression): Boolean {
+      if (element.expression?.text == null) {
+        return false
+      }
+
+      val reference = (element.expression as? DartReference)?.resolve()
+      if (DartComponentType.typeOf(reference) == DartComponentType.CONSTRUCTOR) {
+        return true
+      }
+
+      return false
+    }
+
+    override fun getElementInfo(element: DartCallExpression): String = element.expression?.text!!
+  }
+
+  /**
+   * Generates crumbs for non-local variables.
+   */
+  private object NonLocalVariableHandler : ElementHandler<DartVarDeclarationList>(DartVarDeclarationList::class.java) {
+    override fun accepts(element: DartVarDeclarationList): Boolean = !isInMethodOrFunction(element)
+
+    override fun getElementInfo(element: DartVarDeclarationList): String =
+      element.varAccessDeclaration.componentName.text
+
+    override fun getElementIcon(element: DartVarDeclarationList): Icon? = DartComponentType.GLOBAL_VARIABLE.icon
+  }
+
+  /**
+   * Generates crumbs for named types like classes, enums, mixins, functions, methods, getters, and setters.
+   */
+  private object NamedTypeHandler : ElementHandler<DartComponent>(DartComponent::class.java) {
+    override fun accepts(element: DartComponent): Boolean =
+      (
+        element is DartMethodDeclaration
+        || element is DartGetterDeclaration
+        || element is DartSetterDeclaration
+        || element is DartFunctionDeclarationWithBodyOrNative
+        || element is DartClassDefinition
+        || element is DartEnumDefinition
+        || element is DartEnumConstantDeclaration
+        || element is DartMixinDeclaration
+      ) && !isInMethodOrFunction(element)
+
+    override fun getElementInfo(element: DartComponent): String {
+      val name = element.name ?: element.text
+
+      if (element is DartSetterDeclaration) return "set $name"
+      if (element is DartGetterDeclaration) return "get $name"
+
+      return name
+    }
+  }
+
+  /**
+   * Generates crumbs for `group('...')` and `test('...')` calls in Dart unit tests.
+   */
+  private object UnitTestHandler : ElementHandler<DartCallExpression>(DartCallExpression::class.java) {
+    override fun accepts(element: DartCallExpression): Boolean {
+      val name = expressionName(element)
+      return name == "test" || name == "group"
+    }
+
+    override fun getElementInfo(element: DartCallExpression): String {
+      val name = expressionName(element)
+      val label = getTestLabel(element)
+      return "$name('$label')"
+    }
+
+    private fun expressionName(element: DartCallExpression): String? =
+      (element.expression as? DartReferenceExpression)?.text
+
+    private fun getTestLabel(testCallExpression: DartCallExpression): String? {
+      val arguments = testCallExpression.arguments
+      val argumentList = arguments?.argumentList
+      val argumentExpressions = argumentList?.expressionList
+
+      // The first argument to a `group(...)` or `test(...)` call is the label
+      if (argumentExpressions?.isNotEmpty() == true) {
+        if (argumentExpressions[0] is DartStringLiteralExpression) {
+          return StringUtil.unquoteString(argumentExpressions[0].text)
+        }
+      }
+
+      return null
+    }
+  }
+}
+
+/**
+ * Determines whether the element is nested inside a method or function body.
+ */
+private fun isInMethodOrFunction(element: DartPsiCompositeElement): Boolean {
+  val parents = element.parents(false).iterator()
+  while (parents.hasNext()) {
+    if (parents.next() is DartFunctionBody) {
+      return true
+    }
+  }
+  return false
+}

Dart/testData/breadcrumbs/class.dart

@@ -0,0 +1,3 @@
+class FooClass {
+  <caret>
+}

Dart/testData/breadcrumbs/classVariable.dart

@@ -0,0 +1,3 @@
+class FooClass {
+  final bar<caret> = "value";
+}

Dart/testData/breadcrumbs/classVariable_crumbs.txt

@@ -0,0 +1,2 @@
+FooClass
+bar

Dart/testData/breadcrumbs/class_crumbs.txt

@@ -0,0 +1 @@
+FooClass

Dart/testData/breadcrumbs/enum.dart

@@ -0,0 +1,3 @@
+enum FooEnum {
+  E<caret>
+}

Dart/testData/breadcrumbs/enum_crumbs.txt

@@ -0,0 +1,2 @@
+FooEnum
+E

Dart/testData/breadcrumbs/fileVariable.dart

@@ -0,0 +1 @@
+final f<caret>oo = "value";

Dart/testData/breadcrumbs/fileVariable_crumbs.txt

@@ -0,0 +1 @@
+foo

Dart/testData/breadcrumbs/function.dart

@@ -0,0 +1,3 @@
+String funcName() {
+  return "foo";<caret>
+}

Dart/testData/breadcrumbs/function_crumbs.txt

@@ -0,0 +1 @@
+funcName

Dart/testData/breadcrumbs/getter.dart

@@ -0,0 +1,5 @@
+class FooClass {
+  String get foo {
+    return "foo";<caret>
+  }
+}

Dart/testData/breadcrumbs/getterFatArrow.dart

@@ -0,0 +1,3 @@
+class FooClass {
+  String get foo => "foo"<caret>;
+}

Dart/testData/breadcrumbs/getterFatArrow_crumbs.txt

@@ -0,0 +1,2 @@
+FooClass
+get foo

Dart/testData/breadcrumbs/getter_crumbs.txt

@@ -0,0 +1,2 @@
+FooClass
+get foo

Dart/testData/breadcrumbs/localVariable.dart

@@ -0,0 +1,5 @@
+class FooClass {
+  void methodName() {
+    final fo<caret>o = "bar";
+  }
+}

Dart/testData/breadcrumbs/localVariable_crumbs.txt

@@ -0,0 +1,2 @@
+FooClass
+methodName

Dart/testData/breadcrumbs/method.dart

@@ -0,0 +1,5 @@
+class FooClass {
+  String methodName() {
+    return "foo";<caret>
+  }
+}

Dart/testData/breadcrumbs/method_crumbs.txt

@@ -0,0 +1,2 @@
+FooClass
+methodName

Dart/testData/breadcrumbs/mixin.dart

@@ -0,0 +1,3 @@
+mixin FooMixin {
+  <caret>
+}

Dart/testData/breadcrumbs/mixin_crumbs.txt

@@ -0,0 +1 @@
+FooMixin

Dart/testData/breadcrumbs/setter.dart

@@ -0,0 +1,5 @@
+class FooClass {
+  set foo(String str) {
+    <caret>
+  }
+}

Dart/testData/breadcrumbs/setterFatArrow.dart

@@ -0,0 +1,3 @@
+class FooClass {
+  set foo(String str) => print('')<caret>;
+}

Dart/testData/breadcrumbs/setterFatArrow_crumbs.txt

@@ -0,0 +1,2 @@
+FooClass
+set foo

Dart/testData/breadcrumbs/setter_crumbs.txt

@@ -0,0 +1,2 @@
+FooClass
+set foo

Dart/testData/breadcrumbs/unitTest.dart

@@ -0,0 +1,7 @@
+void main() {
+  group('Group', () {
+    test("Test", () {
+      <caret>
+    });
+  });
+}

Dart/testData/breadcrumbs/unitTest_crumbs.txt

@@ -0,0 +1,3 @@
+main
+group('Group')
+test('Test')

Dart/testSrc/com/jetbrains/lang/dart/breadcrumbs/DartBreadcrumbsTest.java

@@ -0,0 +1,78 @@
+// Copyright 2000-2022 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package com.jetbrains.lang.dart.breadcrumbs;
+
+import com.intellij.ui.components.breadcrumbs.Crumb;
+import com.jetbrains.lang.dart.DartCodeInsightFixtureTestCase;
+
+import java.util.List;
+import java.util.stream.Collectors;
+
+public class DartBreadcrumbsTest extends DartCodeInsightFixtureTestCase {
+  @Override
+  protected String getTestDataPath() {
+    return super.getTestDataPath() + "/breadcrumbs";
+  }
+
+  private void doTest() {
+    final String testName = getTestName(true);
+    myFixture.configureByFile(testName + ".dart");
+    final String breadcrumbsAndTooltips = getBreadcrumbsAndTooltips(myFixture.getBreadcrumbsAtCaret());
+    assertSameLinesWithFile(getTestDataPath() + "/" + testName + "_crumbs.txt", breadcrumbsAndTooltips);
+  }
+
+  private static String getBreadcrumbsAndTooltips(List<Crumb> crumbs) {
+    return crumbs.stream().map(Crumb::getText).collect(Collectors.joining("\n"));
+  }
+
+  public void testClass() {
+    doTest();
+  }
+
+  public void testClassVariable() {
+    doTest();
+  }
+
+  public void testEnum() {
+    doTest();
+  }
+
+  public void testFileVariable() {
+    doTest();
+  }
+
+  public void testFunction() {
+    doTest();
+  }
+
+  public void testGetter() {
+    doTest();
+  }
+
+  public void testGetterFatArrow() {
+    doTest();
+  }
+
+  public void testLocalVariable() {
+    doTest();
+  }
+
+  public void testMethod() {
+    doTest();
+  }
+
+  public void testMixin() {
+    doTest();
+  }
+
+  public void testSetter() {
+    doTest();
+  }
+
+  public void testSetterFatArrow() {
+    doTest();
+  }
+
+  public void testUnitTest() {
+    doTest();
+  }
+}