Add filteredOnAssertions method

src/main/java/org/assertj/eclipse/collections/api/AbstractRichIterableAssert.java

@@ -308,6 +308,24 @@ public SELF filteredOn(Predicate<? super ELEMENT> predicate) {
     return internalFilteredOn(predicate::test);
   }
 
+  @Override
+  @CheckReturnValue
+  public SELF filteredOnAssertions(Consumer<? super ELEMENT> elementAssertions) {
+    checkArgument(elementAssertions != null, "The element assertions should not be null");
+    return internalFilteredOn(byPassingAssertions(elementAssertions)::test);
+  }
+
+  protected static <T> Predicate<T> byPassingAssertions(Consumer<? super T> assertions) {
+    return objectToTest -> {
+      try {
+        assertions.accept(objectToTest);
+        return true;
+      } catch (AssertionError e) {
+        return false;
+      }
+    };
+  }
+
   /**
    * Verifies that the size of the actual RichIterable is equal to the size of the given iterable.
    *

src/test/java/org/assertj/eclipse/collections/api/richiterable/AbstractRichIterableAssert_FilteredOnAssertions_Test.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright 2025-2026 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.assertj.eclipse.collections.api.richiterable;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
+import static org.assertj.core.api.Assertions.assertThatNoException;
+
+import java.util.function.Consumer;
+
+import org.assertj.core.api.ThrowingConsumer;
+
+class AbstractRichIterableAssert_FilteredOnAssertions_Test {
+  @RichIterableParameterizedTest
+  void filteredOnAssertions_consumer_passes(RichIterableAssertFactory<String> assertFactory) {
+    assertThatNoException().isThrownBy(() -> assertFactory.fromElements("TOS", "TNG", "DS9", "VOY", "ENT")
+      .filteredOnAssertions((Consumer<String>) s -> assertThat(s).startsWith("T"))
+      .hasSize(2)
+      .containsOnly("TOS", "TNG"));
+  }
+
+  @RichIterableParameterizedTest
+  void filteredOnAssertions_consumer_noElementPassesAssertions_filtersEverything(RichIterableAssertFactory<String> assertFactory) {
+    assertThatNoException().isThrownBy(() -> assertFactory.fromElements("TOS", "TNG", "DS9", "VOY", "ENT")
+      .filteredOnAssertions((Consumer<String>) s -> assertThat(s).hasSize(4))
+      .isEmpty());
+  }
+
+  @SuppressWarnings({"rawtypes", "unchecked"})
+  @RichIterableParameterizedTest
+  void filteredOnAssertions_consumer_nullConsumer_throwsException(RichIterableAssertFactory<String> assertFactory) {
+    assertThatExceptionOfType(IllegalArgumentException.class)
+      .isThrownBy(() -> assertFactory.fromElements("TOS", "TNG", "DS9", "VOY", "ENT").filteredOnAssertions((Consumer) null))
+      .withMessageContaining("The element assertions should not be null");
+  }
+
+  @SuppressWarnings("RedundantCast")
+  @RichIterableParameterizedTest
+  void filteredOnAssertions_throwingConsumer_passes(RichIterableAssertFactory<String> assertFactory) {
+    assertThatNoException().isThrownBy(() -> assertFactory.fromElements("TOS", "TNG", "DS9", "VOY", "ENT")
+      .filteredOnAssertions((ThrowingConsumer<String>) s -> assertThat(s).startsWith("T"))
+      .hasSize(2)
+      .containsOnly("TOS", "TNG"));
+  }
+
+  @SuppressWarnings("RedundantCast")
+  @RichIterableParameterizedTest
+  void filteredOnAssertions_throwingConsumer_noElementPassesAssertions_filtersEverything(RichIterableAssertFactory<String> assertFactory) {
+    assertThatNoException().isThrownBy(() -> assertFactory.fromElements("TOS", "TNG", "DS9", "VOY", "ENT")
+      .filteredOnAssertions((ThrowingConsumer<String>) s -> assertThat(s).hasSize(4))
+      .isEmpty());
+  }
+
+  @SuppressWarnings({"RedundantCast", "rawtypes", "unchecked"})
+  @RichIterableParameterizedTest
+  void filteredOnAssertions_throwingConsumer_nullConsumer_throwsException(RichIterableAssertFactory<String> assertFactory) {
+    assertThatExceptionOfType(IllegalArgumentException.class)
+      .isThrownBy(() -> assertFactory.fromElements("TOS", "TNG", "DS9", "VOY", "ENT").filteredOnAssertions((ThrowingConsumer) null))
+      .withMessageContaining("The element assertions should not be null");
+  }
+}