feature: add support for Java 16 pattern matching (JEP 394) (#4020)

doc/code_elements.md

@@ -425,6 +425,19 @@ int x = switch(i) { // <-- switch expression
     // fake field "class"
     Class x = Number.class
 
+```
+### CtTypePattern
+[(javadoc)](http://spoon.gforge.inria.fr/mvnsites/spoon-core/apidocs/spoon/reflect/code/CtTypePattern.html)
+
+```java
+
+    Object obj = null;
+    boolean longerThanTwo = false;
+    // String s is the type pattern, declaring a local variable
+    if (obj instanceof String s) {
+        longerThanTwo = s.length() > 2;
+    }
+
 ```
 ### CtUnaryOperator
 [(javadoc)](http://spoon.gforge.inria.fr/mvnsites/spoon-core/apidocs/spoon/reflect/code/CtUnaryOperator.html)

spoon-control-flow/pom.xml

@@ -85,7 +85,7 @@
         <dependency>
             <groupId>fr.inria.gforge.spoon</groupId>
             <artifactId>spoon-core</artifactId>
-            <version>9.0.0</version>
+            <version>9.2.0-SNAPSHOT</version>
         </dependency>
 
         <dependency>

spoon-control-flow/src/main/java/fr/inria/controlflow/ControlFlowBuilder.java

@@ -68,6 +68,7 @@
 import spoon.reflect.code.CtTry;
 import spoon.reflect.code.CtTryWithResource;
 import spoon.reflect.code.CtTypeAccess;
+import spoon.reflect.code.CtTypePattern;
 import spoon.reflect.code.CtUnaryOperator;
 import spoon.reflect.code.CtVariableRead;
 import spoon.reflect.code.CtVariableWrite;
@@ -974,4 +975,9 @@ public void visitCtTypeMemberWildcardImportReference(CtTypeMemberWildcardImportR
 	public void visitCtYieldStatement(CtYieldStatement ctYieldStatement) {
 
 	}
+
+	@Override
+	public void visitCtTypePattern(CtTypePattern pattern) {
+
+	}
 }

spoon-smpl/pom.xml

@@ -109,7 +109,7 @@
         <dependency>
             <groupId>fr.inria.gforge.spoon</groupId>
             <artifactId>spoon-core</artifactId>
-            <version>9.0.0</version>
+            <version>9.2.0-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>fr.inria.gforge.spoon</groupId>

spoon-smpl/src/main/java/spoon/smpl/Substitutor.java

@@ -70,6 +70,7 @@
 import spoon.reflect.code.CtTry;
 import spoon.reflect.code.CtTryWithResource;
 import spoon.reflect.code.CtTypeAccess;
+import spoon.reflect.code.CtTypePattern;
 import spoon.reflect.code.CtUnaryOperator;
 import spoon.reflect.code.CtVariableRead;
 import spoon.reflect.code.CtVariableWrite;
@@ -680,4 +681,9 @@ public void visitCtTypeMemberWildcardImportReference(CtTypeMemberWildcardImportR
 	public void visitCtYieldStatement(CtYieldStatement ctYieldStatement) {
 		throw new NotImplementedException("Not implemented");
 	}
+
+	@Override
+	public void visitCtTypePattern(CtTypePattern pattern) {
+		throw new NotImplementedException("Not implemented");
+	}
 }

spoon-smpl/src/main/java/spoon/smpl/pattern/PatternBuilder.java

@@ -68,6 +68,7 @@
 import spoon.reflect.code.CtTry;
 import spoon.reflect.code.CtTryWithResource;
 import spoon.reflect.code.CtTypeAccess;
+import spoon.reflect.code.CtTypePattern;
 import spoon.reflect.code.CtUnaryOperator;
 import spoon.reflect.code.CtVariableRead;
 import spoon.reflect.code.CtVariableWrite;
@@ -821,6 +822,11 @@ public void visitCtYieldStatement(CtYieldStatement ctYieldStatement) {
 		throw new NotImplementedException("Not implemented");
 	}
 
+	@Override
+	public void visitCtTypePattern(CtTypePattern pattern) {
+		throw new NotImplementedException("Not implemented");
+	}
+
 	/**
 	 * Parameter identifiers.
 	 */

src/main/java/spoon/metamodel/Metamodel.java

@@ -105,6 +105,7 @@ public static Set<CtType<?>> getAllMetamodelInterfaces() {
 		result.add(factory.Type().get(spoon.reflect.code.CtNewArray.class));
 		result.add(factory.Type().get(spoon.reflect.code.CtNewClass.class));
 		result.add(factory.Type().get(spoon.reflect.code.CtOperatorAssignment.class));
+		result.add(factory.Type().get(spoon.reflect.code.CtPattern.class));
 		result.add(factory.Type().get(spoon.reflect.code.CtRHSReceiver.class));
 		result.add(factory.Type().get(spoon.reflect.code.CtReturn.class));
 		result.add(factory.Type().get(spoon.reflect.code.CtStatement.class));
@@ -119,6 +120,7 @@ public static Set<CtType<?>> getAllMetamodelInterfaces() {
 		result.add(factory.Type().get(spoon.reflect.code.CtTry.class));
 		result.add(factory.Type().get(spoon.reflect.code.CtTryWithResource.class));
 		result.add(factory.Type().get(spoon.reflect.code.CtTypeAccess.class));
+		result.add(factory.Type().get(spoon.reflect.code.CtTypePattern.class));
 		result.add(factory.Type().get(spoon.reflect.code.CtUnaryOperator.class));
 		result.add(factory.Type().get(spoon.reflect.code.CtVariableAccess.class));
 		result.add(factory.Type().get(spoon.reflect.code.CtVariableRead.class));

src/main/java/spoon/reflect/code/CtPattern.java

@@ -0,0 +1,18 @@
+/*
+ * SPDX-License-Identifier: (MIT OR CECILL-C)
+ *
+ * Copyright (C) 2006-2019 INRIA and contributors
+ *
+ * Spoon is available either under the terms of the MIT License (see LICENSE-MIT.txt) of the Cecill-C License (see LICENSE-CECILL-C.txt). You as the user are entitled to choose the terms under which to adopt Spoon.
+ */
+package spoon.reflect.code;
+
+import spoon.reflect.declaration.CtElement;
+
+/**
+ * This interface represents a common super type for different
+ * patterns implemented in the Java language.
+ */
+public interface CtPattern extends CtElement {
+
+}

src/main/java/spoon/reflect/code/CtTypePattern.java

@@ -0,0 +1,66 @@
+/*
+ * SPDX-License-Identifier: (MIT OR CECILL-C)
+ *
+ * Copyright (C) 2006-2019 INRIA and contributors
+ *
+ * Spoon is available either under the terms of the MIT License (see LICENSE-MIT.txt) of the Cecill-C License (see LICENSE-CECILL-C.txt). You as the user are entitled to choose the terms under which to adopt Spoon.
+ */
+package spoon.reflect.code;
+
+import spoon.reflect.annotations.PropertyGetter;
+import spoon.reflect.annotations.PropertySetter;
+import spoon.reflect.reference.CtTypeReference;
+import spoon.support.UnsettableProperty;
+
+import java.util.List;
+
+import static spoon.reflect.path.CtRole.VARIABLE;
+
+/**
+ * This code element defines a type pattern, introduced in Java 16
+ * by <a href=https://openjdk.java.net/jeps/394>JEP 394</a>.
+ * <p>
+ * Example:
+ * <pre>
+ *     Object obj = null;
+ *     boolean longerThanTwo = false;
+ *     // String s is the type pattern, declaring a local variable
+ *     if (obj instanceof String s) {
+ *         longerThanTwo = s.length() > 2;
+ *     }
+ * </pre>
+ */
+public interface CtTypePattern extends CtPattern, CtExpression<Void> {
+
+	/**
+	 * Returns the local variable declared by this type pattern.
+	 *
+	 * @return the local variable.
+	 */
+	@PropertyGetter(role = VARIABLE)
+	CtLocalVariable<?> getVariable();
+
+	/**
+	 * Sets the local variable for this type pattern.
+	 *
+	 * @param variable the variable to set for this type pattern.
+	 * @return this pattern.
+	 */
+	@PropertySetter(role = VARIABLE)
+	CtTypePattern setVariable(CtLocalVariable<?> variable);
+
+	@Override
+	CtTypePattern clone();
+
+	@Override
+	@UnsettableProperty
+	List<CtTypeReference<?>> getTypeCasts();
+
+	@Override
+	@UnsettableProperty
+	<C extends CtExpression<Void>> C setTypeCasts(List<CtTypeReference<?>> types);
+
+	@Override
+	@UnsettableProperty
+	<C extends CtExpression<Void>> C addTypeCast(CtTypeReference<?> type);
+}

src/main/java/spoon/reflect/factory/CoreFactory.java

@@ -55,6 +55,7 @@
 import spoon.reflect.code.CtTry;
 import spoon.reflect.code.CtTryWithResource;
 import spoon.reflect.code.CtTypeAccess;
+import spoon.reflect.code.CtTypePattern;
 import spoon.reflect.code.CtUnaryOperator;
 import spoon.reflect.code.CtVariableRead;
 import spoon.reflect.code.CtVariableWrite;
@@ -619,4 +620,10 @@ BodyHolderSourcePosition createBodyHolderSourcePosition(
 	 * Creates a TextBlock String Literal
 	 */
 	CtTextBlock createTextBlock();
+
+	/**
+	 * Creates a Type Pattern
+	 * @return a new Type Pattern instance.
+	 */
+	CtTypePattern createTypePattern();
 }