Merge pull request #2003 from matozoid/issue_1997_more_lambda_expr_co…

…nstructors Give LambdaExpr some useful constructors.
javaparser · Jan 4, 2019 · d0e1b63 · d0e1b63
2 parents 147bb9c + 5d3b665
commit d0e1b63
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Showing 2 changed files with 81 additions and 14 deletions.
diff --git a/javaparser-core-testing/src/test/java/com/github/javaparser/ast/expr/LambdaExprTest.java b/javaparser-core-testing/src/test/java/com/github/javaparser/ast/expr/LambdaExprTest.java
@@ -2,20 +2,24 @@
 
 import com.github.javaparser.TokenRange;
 import com.github.javaparser.ast.Node;
+import com.github.javaparser.ast.NodeList;
+import com.github.javaparser.ast.body.Parameter;
+import com.github.javaparser.ast.type.UnknownType;
 import org.junit.jupiter.api.Test;
 
-import static com.github.javaparser.JavaParser.parseExpression;
-import static org.junit.jupiter.api.Assertions.*;
+import static com.github.javaparser.JavaParser.*;
+import static com.github.javaparser.utils.TestUtils.assertEqualsNoEol;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
 class LambdaExprTest {
     @Test
-    void lambdaRange1(){
+    void lambdaRange1() {
         Expression expression = parseExpression("x -> y");
         assertRange("x", "y", expression);
     }
 
     @Test
-    void lambdaRange2(){
+    void lambdaRange2() {
         Expression expression = parseExpression("(x) -> y");
         assertRange("(", "y", expression);
     }
@@ -27,15 +31,45 @@ private void assertRange(String startToken, String endToken, Node node) {
     }
 
     @Test
-    void getExpressionBody(){
+    void getExpressionBody() {
         LambdaExpr lambdaExpr = parseExpression("x -> y").asLambdaExpr();
         assertEquals("Optional[y]", lambdaExpr.getExpressionBody().toString());
     }
 
     @Test
-    void getNoExpressionBody(){
+    void getNoExpressionBody() {
         LambdaExpr lambdaExpr = parseExpression("x -> {y;}").asLambdaExpr();
         assertEquals("Optional.empty", lambdaExpr.getExpressionBody().toString());
     }
 
+    @Test
+    void oneParameterAndExpressionUtilityConstructor() {
+        LambdaExpr expr = new LambdaExpr(new Parameter(new UnknownType(), "a"), parseExpression("5"));
+        assertEquals("a -> 5", expr.toString());
+    }
+
+    @Test
+    void oneParameterAndStatementUtilityConstructor() {
+        LambdaExpr expr = new LambdaExpr(new Parameter(new UnknownType(), "a"), parseBlock("{return 5;}"));
+        assertEqualsNoEol("a -> {\n    return 5;\n}", expr.toString());
+    }
+
+    @Test
+    void multipleParametersAndExpressionUtilityConstructor() {
+        LambdaExpr expr = new LambdaExpr(new NodeList<>(new Parameter(new UnknownType(), "a"), new Parameter(new UnknownType(), "b")), parseExpression("5"));
+        assertEquals("(a, b) -> 5", expr.toString());
+    }
+
+    @Test
+    void multipleParametersAndStatementUtilityConstructor() {
+        LambdaExpr expr = new LambdaExpr(new NodeList<>(new Parameter(new UnknownType(), "a"), new Parameter(new UnknownType(), "b")), parseBlock("{return 5;}"));
+        assertEqualsNoEol("(a, b) -> {\n    return 5;\n}", expr.toString());
+    }
+
+    @Test
+    void zeroParametersAndStatementUtilityConstructor() {
+        LambdaExpr expr = new LambdaExpr(new NodeList<>(), parseBlock("{return 5;}"));
+        assertEqualsNoEol("() -> {\n    return 5;\n}", expr.toString());
+    }
+
 }
diff --git a/javaparser-core/src/main/java/com/github/javaparser/ast/expr/LambdaExpr.java b/javaparser-core/src/main/java/com/github/javaparser/ast/expr/LambdaExpr.java
@@ -20,25 +20,29 @@
  */
 package com.github.javaparser.ast.expr;
 
+import com.github.javaparser.TokenRange;
 import com.github.javaparser.ast.AllFieldsConstructor;
+import com.github.javaparser.ast.Generated;
+import com.github.javaparser.ast.Node;
 import com.github.javaparser.ast.NodeList;
 import com.github.javaparser.ast.body.Parameter;
 import com.github.javaparser.ast.nodeTypes.NodeWithParameters;
 import com.github.javaparser.ast.observer.ObservableProperty;
+import com.github.javaparser.ast.stmt.BlockStmt;
+import com.github.javaparser.ast.stmt.ExpressionStmt;
 import com.github.javaparser.ast.stmt.ReturnStmt;
 import com.github.javaparser.ast.stmt.Statement;
+import com.github.javaparser.ast.visitor.CloneVisitor;
 import com.github.javaparser.ast.visitor.GenericVisitor;
 import com.github.javaparser.ast.visitor.VoidVisitor;
-import java.util.Optional;
-import static com.github.javaparser.utils.Utils.assertNotNull;
-import com.github.javaparser.ast.Node;
-import com.github.javaparser.ast.visitor.CloneVisitor;
 import com.github.javaparser.metamodel.DerivedProperty;
-import com.github.javaparser.metamodel.LambdaExprMetaModel;
 import com.github.javaparser.metamodel.JavaParserMetaModel;
-import com.github.javaparser.TokenRange;
+import com.github.javaparser.metamodel.LambdaExprMetaModel;
+
+import java.util.Optional;
 import java.util.function.Consumer;
-import com.github.javaparser.ast.Generated;
+
+import static com.github.javaparser.utils.Utils.assertNotNull;
 
 /**
  * <h1>A lambda expression</h1>
@@ -52,7 +56,7 @@
  * If a parameter uses type inference (it has no type specified) then its type is set to <code>UnknownType</code>.
  * If they are in ( ), "isEnclosingParameters" is true.
  * <br/>The body is to the right of the ->.
- * The body is either a BlockStatement when it is in { } braces, or an ExpressionStatement when it is not in braces.
+ * The body is either a BlockStmt when it is in { } braces, or an ExpressionStmt when it is not in braces.
  *
  * @author Raquel Pau
  */
@@ -68,6 +72,35 @@ public LambdaExpr() {
         this(null, new NodeList<>(), new ReturnStmt(), false);
     }
 
+    /**
+     * Creates a single parameter lambda expression.
+     */
+    public LambdaExpr(Parameter parameter, BlockStmt body) {
+        this(null, new NodeList<>(parameter), body, false);
+    }
+
+    /**
+     * Creates a zero or multi-parameter lambda expression with its parameters wrapped in ( ).
+     */
+    public LambdaExpr(NodeList<Parameter> parameters, BlockStmt body) {
+        this(null, parameters, body, true);
+    }
+
+
+    /**
+     * Creates a single parameter lambda expression.
+     */
+    public LambdaExpr(Parameter parameter, Expression body) {
+        this(null, new NodeList<>(parameter), new ExpressionStmt(body), false);
+    }
+
+    /**
+     * Creates a zero or multi-parameter lambda expression with its parameters wrapped in ( ).
+     */
+    public LambdaExpr(NodeList<Parameter> parameters, Expression body) {
+        this(null, parameters, new ExpressionStmt(body), true);
+    }
+
     @AllFieldsConstructor
     public LambdaExpr(NodeList<Parameter> parameters, Statement body, boolean isEnclosingParameters) {
         this(null, parameters, body, isEnclosingParameters);