Skip to content

Skip Hamcrest matchers that take nested matchers in HamcrestMatcherToAssertJ #1236

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
timtebeek merged 5 commits into from
Oct 25, 2026
Merged

Skip Hamcrest matchers that take nested matchers in HamcrestMatcherToAssertJ #1236

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
5 commits
Select commit Hold shift + click to select a range
40c5861
Remove `CoreMatchers` imports in the reason path of `HamcrestNotMatch…
timtebeek Oct 25, 2026
de466e2
Skip Hamcrest matchers that take nested matchers in `HamcrestMatcherT…
timtebeek Oct 25, 2026
7bce07e
Skip varargs arrays that do not fit the actual elements in `HamcrestM…
timtebeek Oct 25, 2026
7b1c129
Drop unused parameter declaration from `JMockitMockUpToMockitoTest` e…
timtebeek Oct 25, 2026
5e80091
Merge remote-tracking branch 'origin/main' into tim/hamcrest-assertj-…
timtebeek Oct 25, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
44 changes: 42 additions & 2 deletions src/main/java/org/openrewrite/java/testing/hamcrest/HamcrestMatcherToAssertJ.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -36,7 +36,7 @@
@AllArgsConstructor
public class HamcrestMatcherToAssertJ extends Recipe {
private static final MethodMatcher ASSERT_THAT_MATCHER = new MethodMatcher("org.hamcrest.MatcherAssert assertThat(..)");
private static final MethodMatcher SUB_MATCHER = new MethodMatcher("org.hamcrest.*Matchers *(org.hamcrest.Matcher)");
private static final String HAMCREST_MATCHER = "org.hamcrest.Matcher";
private static final MethodMatcher CLOSE_TO_MATCHER = new MethodMatcher("org.hamcrest.Matchers closeTo(..)");

@Option(displayName = "Hamcrest matcher",
Expand Down Expand Up @@ -91,12 +91,15 @@ private J.MethodInvocation replace(J.MethodInvocation mi, ExecutionContext ctx)
Expression reasonArgument = mia.size() == 3 ? mia.get(0) : null;
Expression actualArgument = mia.get(mia.size() - 2);
Expression matcherArgument = mia.get(mia.size() - 1);
if (!matchersMatcher.matches(matcherArgument) || SUB_MATCHER.matches(matcherArgument)) {
if (!matchersMatcher.matches(matcherArgument) || takesMatcher((J.MethodInvocation) matcherArgument)) {
return mi;
}
if (argumentType != null && !TypeUtils.isAssignableTo(argumentType, actualArgument.getType())) {
return mi;
}
if (passesIncompatibleVarargsArray((J.MethodInvocation) matcherArgument, actualArgument.getType())) {
return mi;
}

String actual = typeToIndicator(actualArgument.getType());
J.MethodInvocation matcherArgumentMethod = (J.MethodInvocation) matcherArgument;
Expand Down Expand Up @@ -194,4 +197,41 @@ private String typeToIndicator(@Nullable JavaType type) {
return "#{any(java.lang.Object)}";
}
}

static boolean takesMatcher(J.MethodInvocation method) {
JavaType.Method methodType = method.getMethodType();
return (methodType != null && methodType.getParameterTypes().stream().anyMatch(HamcrestMatcherToAssertJ::isOrHoldsMatcher)) ||
method.getArguments().stream().anyMatch(arg -> isOrHoldsMatcher(arg.getType()));
}

private static boolean isOrHoldsMatcher(@Nullable JavaType type) {
if (type instanceof JavaType.Array) {
return isOrHoldsMatcher(((JavaType.Array) type).getElemType());
}
if (type instanceof JavaType.Parameterized && TypeUtils.isAssignableTo("java.lang.Iterable", type)) {
return ((JavaType.Parameterized) type).getTypeParameters().stream().anyMatch(param -> TypeUtils.isAssignableTo(HAMCREST_MATCHER, param));
}
return TypeUtils.isAssignableTo(HAMCREST_MATCHER, type);
}

private static boolean passesIncompatibleVarargsArray(J.MethodInvocation matcher, @Nullable JavaType actualType) {
JavaType.Method methodType = matcher.getMethodType();
JavaType elementType = elementType(actualType);
if (methodType == null || !methodType.hasFlags(Flag.Varargs) || elementType == null) {
return false;
}
JavaType lastArgumentType = matcher.getArguments().get(matcher.getArguments().size() - 1).getType();
return lastArgumentType instanceof JavaType.Array && !TypeUtils.isAssignableTo(elementType, ((JavaType.Array) lastArgumentType).getElemType());
}

private static @Nullable JavaType elementType(@Nullable JavaType type) {
if (type instanceof JavaType.Array) {
return ((JavaType.Array) type).getElemType();
}
if (type instanceof JavaType.Parameterized && TypeUtils.isAssignableTo("java.lang.Iterable", type)) {
List<JavaType> typeParameters = ((JavaType.Parameterized) type).getTypeParameters();
return typeParameters.size() == 1 ? typeParameters.get(0) : null;
}
return null;
}
}
76 changes: 20 additions & 56 deletions src/main/java/org/openrewrite/java/testing/hamcrest/HamcrestNotMatcherToAssertJ.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -20,6 +20,7 @@
import lombok.NoArgsConstructor;
import org.jspecify.annotations.Nullable;
import org.openrewrite.*;
import org.openrewrite.internal.ListUtils;
import org.openrewrite.java.JavaIsoVisitor;
import org.openrewrite.java.JavaParser;
import org.openrewrite.java.JavaTemplate;
Expand All @@ -33,14 +34,12 @@
import java.util.List;

import static java.util.stream.Collectors.joining;
import static java.util.stream.Collectors.toList;

@NoArgsConstructor
@AllArgsConstructor
public class HamcrestNotMatcherToAssertJ extends Recipe {
private static final MethodMatcher ASSERT_THAT_MATCHER = new MethodMatcher("org.hamcrest.MatcherAssert assertThat(..)");
private static final MethodMatcher NOT_MATCHER = new MethodMatcher("org.hamcrest.*Matchers not(org.hamcrest.Matcher)");
private static final MethodMatcher SUB_MATCHER = new MethodMatcher("org.hamcrest.*Matchers *(org.hamcrest.Matcher)");

@Option(displayName = "Hamcrest Matcher",
description = "The Hamcrest `not(Matcher)` to migrate to AssertJ.",
Expand Down Expand Up @@ -73,36 +72,29 @@ private class MigrateToAssertJVisitor extends JavaIsoVisitor<ExecutionContext> {
@Override
public J.MethodInvocation visitMethodInvocation(J.MethodInvocation method, ExecutionContext ctx) {
J.MethodInvocation mi = super.visitMethodInvocation(method, ctx);
if (ASSERT_THAT_MATCHER.matches(mi)) {
Expression notMethodInvocation = mi.getArguments().get(mi.getArguments().size() - 1);
if (!NOT_MATCHER.matches(notMethodInvocation)) {
return mi;
}
Expression matcherArgument = ((J.MethodInvocation) notMethodInvocation).getArguments().get(0);
if (mi.getArguments().size() == 2) {
return handleTwoArgumentCase(mi, matcherArgument, ctx);
}
if (mi.getArguments().size() == 3) {
return handleThreeArgumentCase(mi, matcherArgument, ctx);
}
if (!ASSERT_THAT_MATCHER.matches(mi)) {
return mi;
}
return mi;
}

private J.MethodInvocation handleTwoArgumentCase(J.MethodInvocation mi, Expression matcherArgument, ExecutionContext ctx) {
Expression actualArgument = mi.getArguments().get(0);
if (!matchersMatcher.matches(matcherArgument) || SUB_MATCHER.matches(matcherArgument)) {
List<Expression> mia = mi.getArguments();
Expression notMethodInvocation = mia.get(mia.size() - 1);
if (!NOT_MATCHER.matches(notMethodInvocation)) {
return mi;
}
String actual = typeToIndicator(actualArgument.getType());
List<Expression> originalArguments = ((J.MethodInvocation) matcherArgument).getArguments().stream()
.filter(a -> !(a instanceof J.Empty))
.collect(toList());
Expression matcherArgument = ((J.MethodInvocation) notMethodInvocation).getArguments().get(0);
if (!matchersMatcher.matches(matcherArgument) || HamcrestMatcherToAssertJ.takesMatcher((J.MethodInvocation) matcherArgument)) {
return mi;
}
Expression reasonArgument = mia.size() == 3 ? mia.get(0) : null;
Expression actualArgument = mia.get(mia.size() - 2);
List<Expression> originalArguments = ListUtils.filter(((J.MethodInvocation) matcherArgument).getArguments(), a -> !(a instanceof J.Empty));
String argumentsTemplate = originalArguments.stream()
.map(a -> typeToIndicator(a.getType()))
.collect(joining(", "));
JavaTemplate template = JavaTemplate.builder(String.format("assertThat(%s).%s(%s)",
actual, assertion, argumentsTemplate))
JavaTemplate template = JavaTemplate.builder(String.format("assertThat(%s)%s.%s(%s)",
typeToIndicator(actualArgument.getType()),
reasonArgument != null ? ".as(#{any(String)})" : "",
assertion,
argumentsTemplate))
.javaParser(JavaParser.fromJavaVersion().classpathFromResources(ctx, "assertj-core-3"))
.staticImports("org.assertj.core.api.Assertions.assertThat")
.build();
Expand All @@ -116,37 +108,9 @@ private J.MethodInvocation handleTwoArgumentCase(J.MethodInvocation mi, Expressi

List<Expression> templateArguments = new ArrayList<>();
templateArguments.add(actualArgument);
templateArguments.addAll(originalArguments);
return template.apply(getCursor(), mi.getCoordinates().replace(), templateArguments.toArray());
}

private J.MethodInvocation handleThreeArgumentCase(J.MethodInvocation mi, Expression matcherArgument, ExecutionContext ctx) {
Expression reasonArgument = mi.getArguments().get(0);
Expression actualArgument = mi.getArguments().get(1);
if (!matchersMatcher.matches(matcherArgument) || SUB_MATCHER.matches(matcherArgument)) {
return mi;
if (reasonArgument != null) {
templateArguments.add(reasonArgument);
}
String actual = typeToIndicator(actualArgument.getType());
List<Expression> originalArguments = ((J.MethodInvocation) matcherArgument).getArguments().stream()
.filter(a -> !(a instanceof J.Empty))
.collect(toList());
String argumentsTemplate = originalArguments.stream()
.map(a -> typeToIndicator(a.getType()))
.collect(joining(", "));
JavaTemplate template = JavaTemplate.builder(String.format("assertThat(%s).as(#{any(String)}).%s(%s)",
actual, assertion, argumentsTemplate))
.javaParser(JavaParser.fromJavaVersion().classpathFromResources(ctx, "assertj-core-3"))
.staticImports("org.assertj.core.api.Assertions.assertThat")
.build();
maybeRemoveImport("org.hamcrest.Matchers.not");
maybeRemoveImport("org.hamcrest.Matchers." + notMatcher);
maybeRemoveImport("org.hamcrest.MatcherAssert");
maybeRemoveImport("org.hamcrest.MatcherAssert.assertThat");
maybeAddImport("org.assertj.core.api.Assertions", "assertThat");

List<Expression> templateArguments = new ArrayList<>();
templateArguments.add(actualArgument);
templateArguments.add(reasonArgument);
templateArguments.addAll(originalArguments);
return template.apply(getCursor(), mi.getCoordinates().replace(), templateArguments.toArray());
}
Expand Down
132 changes: 111 additions & 21 deletions src/test/java/org/openrewrite/java/testing/hamcrest/HamcrestMatcherToAssertJTest.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -23,7 +23,6 @@
import org.openrewrite.java.JavaParser;
import org.openrewrite.test.RecipeSpec;
import org.openrewrite.test.RewriteTest;
import org.openrewrite.test.TypeValidation;

import static org.openrewrite.java.Assertions.java;

Expand Down Expand Up @@ -136,6 +135,111 @@ void test() {
"""
));
}

@Test
void containsInAnyOrderWithObjectArray() {
rewriteRun(
spec -> spec.recipe(new HamcrestMatcherToAssertJ("containsInAnyOrder", "containsExactlyInAnyOrder", null)),
//language=java
java(
"""
import java.util.List;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.containsInAnyOrder;

class ATest {
void test(List<String> list, List<String> states) {
assertThat(list, containsInAnyOrder(states.toArray()));
}
}
"""
));
}

@Test
void containsVarargsMatchers() {
rewriteRun(
spec -> spec.recipe(new HamcrestMatcherToAssertJ("contains", "containsExactly", null)),
//language=java
java(
"""
import java.util.List;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.contains;
import static org.hamcrest.Matchers.equalTo;
import static org.hamcrest.Matchers.startsWith;

class ATest {
void test(List<String> list) {
assertThat(list, contains(equalTo("a"), startsWith("b")));
assertThat("reason", list, contains(equalTo("a"), startsWith("b")));
}
}
"""
));
}

@Test
void containsListOfMatchers() {
rewriteRun(
spec -> spec.recipe(new HamcrestMatcherToAssertJ("contains", "containsExactly", null)),
//language=java
java(
"""
import java.util.List;
import org.hamcrest.Matcher;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.contains;

class ATest {
void test(List<String> list, List<Matcher<? super String>> matchers) {
assertThat(list, contains(matchers));
}
}
"""
));
}

@Test
void arrayContainingMatchers() {
rewriteRun(
spec -> spec.recipe(new HamcrestMatcherToAssertJ("arrayContaining", "containsExactly", null)),
//language=java
java(
"""
import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.arrayContaining;
import static org.hamcrest.Matchers.equalTo;

class ATest {
void test(String[] array) {
assertThat(array, arrayContaining(equalTo("a"), equalTo("b")));
}
}
"""
));
}

@Test
void hasEntryMatchers() {
rewriteRun(
spec -> spec.recipe(new HamcrestMatcherToAssertJ("hasEntry", "containsEntry", null)),
//language=java
java(
"""
import java.util.Map;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.equalTo;
import static org.hamcrest.Matchers.hasEntry;

class ATest {
void test(Map<String, String> map) {
assertThat(map, hasEntry(equalTo("a"), equalTo("b")));
}
}
"""
));
}
}

@Nested
Expand Down Expand Up @@ -383,45 +487,31 @@ void test() {
);
}

@SuppressWarnings("DataFlowIssue")
@Test
void containsInAnyOrderWithArray() {
rewriteRun(
spec -> spec.recipe(new HamcrestMatcherToAssertJ("containsInAnyOrder", "containsExactlyInAnyOrder", null))
.afterTypeValidationOptions(TypeValidation.all().methodInvocations(false)),
spec -> spec.recipe(new HamcrestMatcherToAssertJ("containsInAnyOrder", "containsExactlyInAnyOrder", null)),
//language=java
java(
"""
import org.junit.jupiter.api.Test;

import java.util.ArrayList;
"""
import java.util.List;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.containsInAnyOrder;

class ATest {
@Test
void test() {
List<String> list = new ArrayList<>();
List<String> states = null;
assertThat(list, containsInAnyOrder(states.toArray()));
void test(List<String> list, List<String> states) {
assertThat(list, containsInAnyOrder(states.toArray(new String[0])));
}
}
""",
"""
import org.junit.jupiter.api.Test;

import java.util.ArrayList;
import java.util.List;

import static org.assertj.core.api.Assertions.assertThat;

class ATest {
@Test
void test() {
List<String> list = new ArrayList<>();
List<String> states = null;
assertThat(list).containsExactlyInAnyOrder(states.toArray());
void test(List<String> list, List<String> states) {
assertThat(list).containsExactlyInAnyOrder(states.toArray(new String[0]));
}
}
"""
Expand Down
Loading