Quick attempt at idomatic AssertJ assertions through Refaster

[timtebeek]

What's changed?

• Added rewrite-templating for Refaster recipe support
• A recipe that aims to rewrite assertThat(actual).isEqualTo(0) to assertThat(actual).isZero()`

What's your motivation?

Get more idiomatic AssertJ assertions developed more easily, from having a first example here.

Anything in particular you'd like reviewers to focus on?

Currently fails as the before template isn't matched

                final JavaTemplate before = JavaTemplate
                        .builder("org.assertj.core.api.Assertions.assertThat(#{actual:any(int)}).isEqualTo(0);")
                        .javaParser(JavaParser.fromJavaVersion().classpath(JavaParser.runtimeClasspath()))
                        .build();

org.assertj.core.api.AbstractIntegerAssert<Generic{SELF extends }>{name=isEqualTo,return=Generic{?},parameters=[int]}

Have you considered any alternatives or workarounds?

Explicit recipe would work for this case, but is less easily developed and maintained, whereas we expect more similar recipes to be welcome here.

Any additional context

• Support additional Refaster features seen in error-prone-support rewrite-templating#47

[timtebeek]

Likely a similar issue to what's explored in

• Troubleshoot mismatched AssertJ AbstractStringAssert.isEqualTo("") rewrite-templating#91

[timtebeek]

Closing this effort for now, as we need an upstream fix in rewrite-templating first, and in parallel we also have

• Chained AssertJ assertions should be simplified to the corresponding dedicated assertion #556
• JavaTemplateSemanticallyEqual fails to match AssertJ's assertThat("foo").isEqualTo("") rewrite#4423

[timtebeek]

We should now already get this recipe applied
https://github.com/PicnicSupermarket/error-prone-support/blob/d94f65a1f03f16fe3d46198ef9658bc4eb41f9cf/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/AssertJIntegerRules.java#L42-L52

After the recent fix in

• Fixes for type attribution and TypeUtils#isAssignableTo() rewrite#4427

[knutwannheden]

Indeed.