From a5f4f0f2ada5c8040d7a02db9b423093f051b1d6 Mon Sep 17 00:00:00 2001 From: Jason O'Brien Date: Wed, 3 Jun 2020 20:23:44 -0500 Subject: Add support for explicit receiver parameters Annotated "this" arguments for instance methods and non-static nested class constructors were added in Java 8. This special cases "this" and "OuterClass.this" so that they are allowed as parameter names. --- .../java/com/squareup/javapoet/ParameterSpec.java | 11 ++++++++++- .../java/com/squareup/javapoet/ParameterSpecTest.java | 19 +++++++++++++++++++ 2 files changed, 29 insertions(+), 1 deletion(-) diff --git a/src/main/java/com/squareup/javapoet/ParameterSpec.java b/src/main/java/com/squareup/javapoet/ParameterSpec.java index 342e657..8b2b6ed 100644 --- a/src/main/java/com/squareup/javapoet/ParameterSpec.java +++ b/src/main/java/com/squareup/javapoet/ParameterSpec.java @@ -103,9 +103,18 @@ public final class ParameterSpec { return result; } + private static boolean isValidParameterName(String name) { + // Allow "this" for explicit receiver parameters + // See https://docs.oracle.com/javase/specs/jls/se8/html/jls-8.html#jls-8.4.1. + if (name.endsWith(".this")) { + return SourceVersion.isIdentifier(name.substring(0, name.length() - ".this".length())); + } + return name.equals("this") || SourceVersion.isName(name); + } + public static Builder builder(TypeName type, String name, Modifier... modifiers) { checkNotNull(type, "type == null"); - checkArgument(SourceVersion.isName(name), "not a valid name: %s", name); + checkArgument(isValidParameterName(name), "not a valid name: %s", name); return new Builder(type, name) .addModifiers(modifiers); } diff --git a/src/test/java/com/squareup/javapoet/ParameterSpecTest.java b/src/test/java/com/squareup/javapoet/ParameterSpecTest.java index 8585986..561eebf 100644 --- a/src/test/java/com/squareup/javapoet/ParameterSpecTest.java +++ b/src/test/java/com/squareup/javapoet/ParameterSpecTest.java @@ -60,6 +60,25 @@ public class ParameterSpecTest { assertThat(a.toString()).isEqualTo(b.toString()); } + @Test public void receiverParameterInstanceMethod() { + ParameterSpec.Builder builder = ParameterSpec.builder(int.class, "this"); + assertThat(builder.build().name).isEqualTo("this"); + } + + @Test public void receiverParameterNestedClass() { + ParameterSpec.Builder builder = ParameterSpec.builder(int.class, "Foo.this"); + assertThat(builder.build().name).isEqualTo("Foo.this"); + } + + @Test public void keywordName() { + try { + ParameterSpec.builder(int.class, "super"); + fail(); + } catch (Exception e) { + assertThat(e.getMessage()).isEqualTo("not a valid name: super"); + } + } + @Test public void nullAnnotationsAddition() { try { ParameterSpec.builder(int.class, "foo").addAnnotations(null); -- cgit v1.2.3