S18 Added OR Tools rules for scheduling show

agiledancers-be/src/test/java/nl/agilecc/agiledancers/S18LifecycleTest.java

@@ -0,0 +1,148 @@
+package nl.agilecc.agiledancers;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.time.LocalDate;
+import java.util.List;
+import java.util.Set;
+import nl.agilecc.agiledancers.model.DanceGroup;
+import nl.agilecc.agiledancers.model.DayPart;
+import nl.agilecc.agiledancers.model.Show;
+import nl.agilecc.agiledancers.model.scheduling.SchedulingInput;
+import nl.agilecc.agiledancers.model.scheduling.SchedulingResult;
+import nl.agilecc.agiledancers.model.specifications.DanceGroupType;
+import nl.agilecc.agiledancers.model.specifications.DayPartType;
+import nl.agilecc.agiledancers.service.ManagementException;
+import nl.agilecc.agiledancers.service.SchedulingInputs;
+import nl.agilecc.agiledancers.service.SchedulingService;
+import nl.agilecc.agiledancers.service.SchoolManagementService;
+import nl.agilecc.agiledancers.service.ShowSchedules;
+import nl.agilecc.agiledancers.service.model.GroupDetails;
+import nl.agilecc.agiledancers.service.model.SchoolSnapshot;
+import nl.agilecc.agiledancers.solver.OrToolsSchedulingEngine;
+import org.junit.jupiter.api.Test;
+
+class S18LifecycleTest {
+    private final SchoolManagementService schools = new SchoolManagementService();
+    private final long school = schools.createSchool("Studio").getId();
+    private final ShowSchedules schedules = new ShowSchedules(schools);
+
+    private List<DayPart> parts(final int n) {
+        return java.util.stream.IntStream.range(0, n)
+                .mapToObj((final int i) -> DayPart.builder()
+                        .date(LocalDate.of(2027, 1, 1).plusDays(i))
+                        .type(DayPartType.MORNING)
+                        .danceGroups(List.of())
+                        .build())
+                .toList();
+    }
+
+    private Show settings(final int n, final Integer x) {
+        return Show.builder()
+                .name("Show")
+                .dayParts(parts(n))
+                .preferredDayParts(x)
+                .build();
+    }
+
+    private DanceGroup group(final DanceGroupType type) {
+        final DanceGroup group = schools.createGroup(school, new GroupDetails("Group", type, 0, 99, Set.of()));
+        final long dancer =
+                schools.createDancer(school, "Dancer", LocalDate.of(2000, 1, 2)).getId();
+        schools.addGroupDancer(school, group.getId(), dancer);
+        return group;
+    }
+
+    public @Test void draftEditingValidationFinalizationAndImportPreserveOrder() {
+        final DanceGroup group = group(DanceGroupType.REGULAR);
+        final Show show = schedules.configure(school, null, settings(2, 1));
+        assertThrows(ManagementException.class, () -> schedules.finalizeSchedule(school, show.getId()));
+        schedules.saveDraft(school, show.getId(), List.of(List.of(group.getId()), List.of()));
+        assertTrue(schedules.violations(school, show.getId()).isEmpty());
+        schedules.finalizeSchedule(school, show.getId());
+        assertTrue(show.isFinalized());
+        final SchoolSnapshot snapshot = schools.exportSchool(school);
+        assertTrue(snapshot.shows().getFirst().finalized());
+        final Show imported = snapshot.restore().getShows().iterator().next();
+        assertFalse(imported.isFinalized());
+        assertEquals(1, imported.getPreferredDayParts());
+        assertEquals(1, imported.getDayParts().getFirst().getDanceGroups().size());
+        schedules.configure(school, show.getId(), settings(2, 1));
+        assertTrue(show.isFinalized());
+        schedules.saveDraft(school, show.getId(), List.of(List.of(), List.of(group.getId())));
+        assertFalse(show.isFinalized());
+        schedules.finalizeSchedule(school, show.getId());
+        schools.removeGroupDancer(
+                school, group.getId(), group.getDancers().iterator().next().getId());
+        assertFalse(show.isFinalized());
+        assertFalse(schedules.violations(school, show.getId()).isEmpty());
+    }
+
+    public @Test void invalidDraftsAreSavedButStructuralErrorsAreAtomic() {
+        final DanceGroup group = group(DanceGroupType.REGULAR);
+        final Show show = schedules.configure(school, null, settings(2, 1));
+        schedules.saveDraft(school, show.getId(), List.of(List.of(group.getId(), group.getId()), List.of()));
+        assertFalse(schedules.violations(school, show.getId()).isEmpty());
+        final SchoolSnapshot before = schools.exportSchool(school);
+        assertThrows(ManagementException.class, () -> schedules.saveDraft(school, show.getId(), List.of()));
+        assertThrows(
+                ManagementException.class,
+                () -> schedules.saveDraft(school, show.getId(), List.of(List.of(), List.of(999L))));
+        assertEquals(before, schools.exportSchool(school));
+    }
+
+    public @Test void xDefaultsRetainedOnDaypartReductionAndInvalidConfigurationIsAtomic() {
+        final Show one = schedules.configure(school, null, settings(1, null));
+        assertEquals(1, one.getPreferredDayParts());
+        final Show show = schedules.configure(school, null, settings(3, null));
+        assertEquals(2, show.getPreferredDayParts());
+        schedules.configure(school, show.getId(), settings(1, null));
+        assertEquals(2, show.getPreferredDayParts());
+        assertThrows(ManagementException.class, () -> schools.beginScheduling(school, show.getId()));
+        schedules.configure(school, show.getId(), settings(1, 1));
+        assertTrue(schedules.violations(school, show.getId()).isEmpty());
+        final int before = schools.shows(school).size();
+        assertThrows(ManagementException.class, () -> schedules.configure(school, null, settings(1, 2)));
+        assertEquals(before, schools.shows(school).size());
+        schedules.configure(school, show.getId(), settings(0, null));
+        assertFalse(schedules.violations(school, show.getId()).isEmpty());
+    }
+
+    public @Test void timeoutPreservesAssignmentsAndIsNotReportedAsInfeasible() {
+        group(DanceGroupType.REGULAR);
+        final Show show = schedules.configure(school, null, settings(1, 1));
+        new SchedulingService(schools, new OrToolsSchedulingEngine()).schedule(school, show.getId());
+        final SchoolSnapshot before = schools.exportSchool(school);
+        final ManagementException error = assertThrows(
+                ManagementException.class,
+                () -> new SchedulingService(schools, new OrToolsSchedulingEngine(0)).schedule(school, show.getId()));
+        assertTrue(error.getMessage().contains("limit"));
+        assertFalse(error.getMessage().contains("infeasible"));
+        assertEquals(before, schools.exportSchool(school));
+    }
+
+    public @Test void emptyGroupsSkippedAndAgeUsesFirstShowDateAcrossDates() {
+        final DanceGroup ordinary = group(DanceGroupType.PRE_EDUCATION);
+        group(DanceGroupType.PRE_SCHOOLER);
+        schools.createGroup(school, new GroupDetails("Empty", DanceGroupType.SHOW_CASE, 0, 99, Set.of()));
+        final Show show = schedules.configure(school, null, settings(3, 1));
+        final SchedulingInput input = schools.beginScheduling(school, show.getId());
+        assertEquals(2, input.groups().size());
+        assertEquals(26, input.groups().getFirst().averageAge());
+        assertEquals(1, input.groups().getFirst().appearances());
+        schools.endScheduling(show.getId());
+        new SchedulingService(schools, new OrToolsSchedulingEngine()).schedule(school, show.getId());
+        assertFalse(show.isFinalized());
+        final SchedulingInput stale = schools.beginScheduling(school, show.getId());
+        final SchedulingResult result = new OrToolsSchedulingEngine().solve(stale);
+        schools.updateDancer(
+                school, ordinary.getDancers().iterator().next().getId(), "Dancer", LocalDate.of(2001, 1, 1));
+        assertThrows(ManagementException.class, () -> schools.finishScheduling(school, stale, result));
+        schools.endScheduling(show.getId());
+        assertEquals(
+                2, SchedulingInputs.of(schools.school(school), show, 0).groups().size());
+    }
+}

agiledancers-be/src/test/java/nl/agilecc/agiledancers/S18ResourceTest.java

@@ -0,0 +1,136 @@
+package nl.agilecc.agiledancers;
+
+import static io.restassured.RestAssured.given;
+import static org.hamcrest.Matchers.empty;
+import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.hasSize;
+
+import io.quarkus.test.junit.QuarkusTest;
+import java.util.List;
+import java.util.Map;
+import org.junit.jupiter.api.Test;
+
+@QuarkusTest
+class S18ResourceTest {
+    private static final String ROOT = "/api/dance-schools";
+
+    private static long create(final String url, final Object body) {
+        return given().contentType("application/json")
+                .body(body)
+                .post(url)
+                .then()
+                .statusCode(201)
+                .extract()
+                .jsonPath()
+                .getLong("id");
+    }
+
+    private static long dancer(final String school, final String name) {
+        return create(school + "/dancers", Map.of("name", name, "birthDate", "1990-01-01"));
+    }
+
+    private static long group(final String school, final long dancer) {
+        final long group = create(
+                school + "/dance-groups",
+                Map.of("category", "Group", "type", "REGULAR", "startAge", 0, "endAge", 99, "styles", List.of()));
+        given().put(school + "/dance-groups/" + group + "/dancers/" + dancer)
+                .then()
+                .statusCode(204);
+        return group;
+    }
+
+    private static String show(final String school) {
+        return school + "/shows/"
+                + create(
+                        school + "/shows",
+                        Map.of(
+                                "name",
+                                "Show",
+                                "preferredDayParts",
+                                1,
+                                "dayParts",
+                                List.of(Map.of("date", "2027-01-01", "type", "MORNING"))));
+    }
+
+    public @Test void draftApiFinalizesOnlyValidSchedulesAndRelevantEditsInvalidateThem() {
+        final String school = ROOT + "/" + create(ROOT, Map.of("name", "S18 lifecycle"));
+        try {
+            final long dancer = dancer(school, "Dancer");
+            final long group = group(school, dancer);
+            final String show = show(school);
+            given().post(show + "/finalize").then().statusCode(400);
+            given().contentType("application/json")
+                    .body(Map.of("assignments", List.of(List.of(group))))
+                    .put(show + "/assignments")
+                    .then()
+                    .statusCode(200)
+                    .body("finalized", equalTo(false), "violations", empty());
+            given().post(show + "/finalize").then().statusCode(200).body("finalized", equalTo(true));
+            given().delete(school + "/dance-groups/" + group + "/dancers/" + dancer)
+                    .then()
+                    .statusCode(204);
+            given().get(show).then().body("finalized", equalTo(false), "violations", hasSize(1));
+            given().contentType("application/json")
+                    .body(Map.of("assignments", List.of(List.of(group, group))))
+                    .put(show + "/assignments")
+                    .then()
+                    .statusCode(200);
+            final String snapshot = given().get(school + "/export").asString();
+            given().contentType("application/json")
+                    .body(snapshot)
+                    .post(ROOT + "/import/preview")
+                    .then()
+                    .statusCode(200);
+        } finally {
+            given().delete(school).then().statusCode(204);
+        }
+    }
+
+    public @Test void coachIdentityIsExplicitSchoolScopedAndRoundTrips() {
+        final String school = ROOT + "/" + create(ROOT, Map.of("name", "S18 coaches"));
+        try {
+            final long dancer = dancer(school, "Coach");
+            group(school, dancer);
+            final String show = show(school);
+            given().post(show + "/schedule").then().statusCode(200);
+            given().post(show + "/finalize").then().statusCode(200);
+            final long coach = given().contentType("application/json")
+                    .body(Map.of("dancerId", dancer))
+                    .post(school + "/coaches")
+                    .then()
+                    .statusCode(200)
+                    .extract()
+                    .jsonPath()
+                    .getLong("id");
+            given().get(show).then().body("finalized", equalTo(false));
+            given().get(school + "/coaches").then().body("[0].dancerId", equalTo((int) dancer));
+            final String exported = given().get(school + "/export").asString();
+            given().contentType("application/json")
+                    .body(exported)
+                    .post(ROOT + "/import?replaceId=" + school.substring(school.lastIndexOf('/') + 1))
+                    .then()
+                    .statusCode(200);
+            given().get(school + "/export").then().body("coaches[0].dancerId", equalTo("1"));
+            final long importedDancer =
+                    given().get(school + "/dancers").jsonPath().getLong("[0].id");
+            given().contentType("application/json")
+                    .body(Map.of("dancerId", importedDancer))
+                    .put(school + "/coaches/0")
+                    .then()
+                    .statusCode(200);
+            given().delete(school + "/coaches/0/dancer").then().statusCode(204);
+            given().contentType("application/json")
+                    .body(Map.of("dancerId", -1))
+                    .post(school + "/coaches")
+                    .then()
+                    .statusCode(404);
+            given().contentType("application/json")
+                    .body(Map.of("dancerId", importedDancer))
+                    .put(school + "/coaches/9999")
+                    .then()
+                    .statusCode(404);
+        } finally {
+            given().delete(school).then().statusCode(204);
+        }
+    }
+}

agiledancers-be/src/test/java/nl/agilecc/agiledancers/S18SolverTest.java

@@ -0,0 +1,133 @@
+package nl.agilecc.agiledancers;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.util.List;
+import java.util.Set;
+import nl.agilecc.agiledancers.model.scheduling.GroupRequirement;
+import nl.agilecc.agiledancers.model.scheduling.ScheduleRules;
+import nl.agilecc.agiledancers.model.scheduling.SchedulingInput;
+import nl.agilecc.agiledancers.model.scheduling.SchedulingResult;
+import nl.agilecc.agiledancers.model.scheduling.VarietyScore;
+import nl.agilecc.agiledancers.model.specifications.DanceGroupStyle;
+import nl.agilecc.agiledancers.service.ManagementException;
+import nl.agilecc.agiledancers.solver.OrToolsSchedulingEngine;
+import org.junit.jupiter.api.Test;
+
+class S18SolverTest {
+    private GroupRequirement group(final long id, final int count, final boolean showcase, final long dancer) {
+        return new GroupRequirement(id, count, showcase, Set.of(dancer), Set.of(), 20);
+    }
+
+    private SchedulingResult solve(final SchedulingInput input) {
+        final SchedulingResult result = new OrToolsSchedulingEngine().solve(input);
+        assertTrue(ScheduleRules.violations(input, result.assignments()).isEmpty());
+        assertTrue(result.optimal());
+        return result;
+    }
+
+    public @Test void showcasesBookendEveryPartAndSharedDancersHaveChangingSpace() {
+        final List<GroupRequirement> groups = List.of(
+                group(1, 2, true, 1),
+                group(2, 2, true, 2),
+                group(3, 2, true, 3),
+                group(4, 1, false, 1),
+                group(5, 1, false, 5),
+                group(6, 1, false, 6),
+                group(7, 1, false, 7));
+        final SchedulingInput input = new SchedulingInput(1, 0, 2, groups, 1, Set.of());
+        final SchedulingResult result = solve(input);
+        for (final List<Long> part : result.assignments()) {
+            assertTrue(part.getFirst() <= 3);
+            assertTrue(part.getLast() <= 3);
+        }
+        assertEquals(
+                1,
+                result.assignments().stream()
+                        .filter((final List<Long> p) -> p.contains(4L))
+                        .count());
+    }
+
+    public @Test void ordinaryDancerMustShareDaypartsAcrossTheirGroups() {
+        final SchedulingInput input = new SchedulingInput(
+                1,
+                0,
+                2,
+                List.of(group(1, 1, false, 1), group(2, 1, false, 1), group(3, 1, false, 3), group(4, 1, false, 4)),
+                1,
+                Set.of());
+        assertThrows(ManagementException.class, () -> solve(input));
+        final SchedulingInput coach = new SchedulingInput(1, 0, 2, input.groups(), 1, Set.of(1L));
+        final SchedulingResult result = solve(coach);
+        assertTrue(result.assignments().stream().allMatch((final List<Long> p) -> p.size() == 2));
+    }
+
+    public @Test void showcaseExcessTakesPriorityOverPerfectBalance() {
+        final SchedulingInput input = new SchedulingInput(
+                1,
+                0,
+                2,
+                List.of(
+                        group(1, 2, true, 1),
+                        group(2, 1, false, 1),
+                        group(3, 1, false, 1),
+                        group(4, 1, false, 4),
+                        group(5, 1, false, 5),
+                        group(6, 1, false, 6),
+                        group(7, 1, false, 7),
+                        group(8, 1, false, 8),
+                        group(9, 1, false, 9),
+                        group(10, 1, false, 10),
+                        group(11, 1, false, 11)),
+                1,
+                Set.of());
+        final SchedulingResult result = solve(input);
+        assertTrue(result.assignments().stream().anyMatch((final List<Long> p) -> p.containsAll(List.of(2L, 3L))));
+        assertEquals(
+                2,
+                Math.abs(result.assignments().get(0).size()
+                        - result.assignments().get(1).size()));
+    }
+
+    public @Test void changingTimeAppliesToCoachesAndShowcasesWithoutExceptions() {
+        final SchedulingInput input =
+                new SchedulingInput(1, 0, 1, List.of(group(1, 1, true, 1), group(2, 1, false, 1)), 1, Set.of(1L));
+        assertThrows(ManagementException.class, () -> solve(input));
+        assertTrue(ScheduleRules.violations(input, List.of(List.of(1L, 2L))).stream()
+                .anyMatch((final String s) -> s.contains("two intervening")));
+    }
+
+    public @Test void singleShowcaseCanUseEitherBoundaryAndNoShowcaseHasNoBoundaryRule() {
+        solve(new SchedulingInput(1, 0, 1, List.of(group(1, 1, true, 1), group(2, 1, false, 2)), 1, Set.of()));
+        solve(new SchedulingInput(1, 0, 1, List.of(group(1, 1, false, 1)), 1, Set.of()));
+    }
+
+    public @Test void sharedValidatorRejectsMalformedAndIncompleteDrafts() {
+        final SchedulingInput input = new SchedulingInput(1, 0, 1, List.of(group(1, 1, false, 1)), 1, Set.of());
+        assertFalse(ScheduleRules.violations(input, null).isEmpty());
+        assertFalse(ScheduleRules.violations(input, List.of()).isEmpty());
+        assertFalse(ScheduleRules.violations(input, List.of(List.of())).isEmpty());
+        assertFalse(ScheduleRules.violations(input, List.of(List.of(1L, 1L))).isEmpty());
+        assertFalse(ScheduleRules.violations(input, List.of(List.of(99L))).isEmpty());
+        final SchedulingInput empty = new SchedulingInput(1, 0, 0, List.of(), 1, Set.of());
+        assertFalse(ScheduleRules.violations(empty, List.of()).isEmpty());
+    }
+
+    public @Test void varietyUsesStyleOverlapAndFiveYearLinearAgePenalty() {
+        final GroupRequirement hiphop =
+                new GroupRequirement(1, 1, false, Set.of(1L), Set.of(DanceGroupStyle.HIPHOP), 10);
+        final GroupRequirement mixed = new GroupRequirement(
+                2, 1, false, Set.of(2L), Set.of(DanceGroupStyle.HIPHOP, DanceGroupStyle.MODERN), 12.5);
+        final GroupRequirement modern =
+                new GroupRequirement(3, 1, false, Set.of(3L), Set.of(DanceGroupStyle.MODERN), 15);
+        assertEquals(1_000_000, VarietyScore.penalty(hiphop, mixed));
+        assertEquals(0, VarietyScore.penalty(hiphop, modern));
+        final List<Long> order = solve(new SchedulingInput(1, 0, 1, List.of(hiphop, mixed, modern), 1, Set.of()))
+                .assignments()
+                .getFirst();
+        assertEquals(1, Math.abs(order.indexOf(1L) - order.indexOf(3L)));
+    }
+}

agiledancers-be/src/test/java/nl/agilecc/agiledancers/SchedulingTest.java

@@ -41,7 +41,12 @@ class SchedulingTest {
     }
 
     private DanceGroup group(final DanceGroupType type) {
-        return service.createGroup(school, new GroupDetails("Group", type, 0, 99, Set.of()));
+        final DanceGroup group = service.createGroup(school, new GroupDetails("Group", type, 0, 99, Set.of()));
+        service.addGroupDancer(
+                school,
+                group.getId(),
+                service.createDancer(school, "Dancer", LocalDate.of(2000, 1, 1)).getId());
+        return group;
     }
 
     private void run(final Show show) {
@@ -86,7 +91,7 @@ class SchedulingTest {
         final Show show = service.createShow(school, "Show", List.of(), null);
         assertTrue(show.getAppearances().isEmpty());
         service.updateShow(school, show.getId(), "Show", parts(3), null);
-        assertEquals(3, show.getAppearances().get(DanceGroupType.PRE_EDUCATION));
+        assertEquals(2, show.getAppearances().get(DanceGroupType.PRE_EDUCATION));
         assertEquals(1, show.getAppearances().get(DanceGroupType.PRE_SCHOOLER));
         final var counts = new EnumMap<>(show.getAppearances());
         counts.put(DanceGroupType.PRE_SCHOOLER, 2);

agiledancers-be/src/test/java/nl/agilecc/agiledancers/SchoolManagementResourceTest.java

@@ -171,15 +171,17 @@ class SchoolManagementResourceTest {
             final String show = school + "/shows/" + create(school + "/shows", SHOW);
             given().post(show + "/schedule").then().statusCode(400);
             final long group = create(school + "/dance-groups", GROUP);
+            final long dancer = create(school + "/dancers", DANCER);
+            given().put(school + "/dance-groups/" + group + "/dancers/" + dancer)
+                    .then()
+                    .statusCode(204);
             given().post(show + "/schedule").then().statusCode(200).body("optimal", equalTo(true));
             given().get(show).then().body("dayParts[0].danceGroupIds", contains((int) group));
             final String before = given().get(show).asString();
-            final String counts =
-                    "{\"SHOW_CASE\":1,\"PRE_EDUCATION\":1,\"SELECTION\":1,\"REGULAR\":%s,\"PRE_SCHOOLER\":1}";
-            for (final String count : new String[] {"0", "2", "1.5", "null"}) {
+            for (final String count : new String[] {"0", "2", "1.5", "7"}) {
                 final String body =
-                        "{\"name\":\"Show\",\"dayParts\":[{\"date\":\"2027-06-12\",\"type\":\"AFTERNOON\"}],\"appearances\":"
-                                + counts.formatted(count) + "}";
+                        "{\"name\":\"Show\",\"dayParts\":[{\"date\":\"2027-06-12\",\"type\":\"AFTERNOON\"}],\"preferredDayParts\":"
+                                + count + "}";
                 put(show, body).statusCode(400);
                 given().get(show).then().body(equalTo(before));
             }

agiledancers-be/src/test/java/nl/agilecc/agiledancers/SchoolSnapshotResourceTest.java

@@ -26,7 +26,7 @@ class SchoolSnapshotResourceTest {
                 .then()
                 .statusCode(200)
                 .header("Content-Disposition", containsString(".json"))
-                .body("formatVersion", equalTo(2))
+                .body("formatVersion", equalTo(3))
                 .extract()
                 .asString();
         try {
@@ -58,7 +58,7 @@ class SchoolSnapshotResourceTest {
         for (final String bad : new String[] {
             "{",
             "null",
-            json.replace("\"formatVersion\" : 2", "\"formatVersion\" : 1"),
+            json.replace("\"formatVersion\" : 3", "\"formatVersion\" : 1"),
             json.replace("\"name\" :", "\"unknown\" :"),
             json + " {}",
             json.replace("\"dancers\" : [ ]", "\"dancers\" : null")

agiledancers-be/src/test/java/nl/agilecc/agiledancers/SnapshotCollectionsTest.java

@@ -58,7 +58,7 @@ class SnapshotCollectionsTest {
     @Test
     public void requestCollectionsRetainTheirJsonValuesAndCannotBeMutatedThroughAliases() {
         final Map<DanceGroupType, Integer> counts = new LinkedHashMap<>(Map.of(DanceGroupType.REGULAR, 1));
-        final ShowRequest show = new ShowRequest("Show", List.of(), counts);
+        final ShowRequest show = new ShowRequest("Show", List.of(), counts, null);
         counts.clear();
         assertEquals(1, show.appearances().get(DanceGroupType.REGULAR));
         assertThrows(

agiledancers-be/src/test/java/nl/agilecc/agiledancers/service/SchedulingServiceTest.java

@@ -29,7 +29,7 @@ class SchedulingServiceTest {
     public @Test void failedAndNoResultRunsPreserveAssignmentsAndReleaseTheRunGuard() {
         final var schools = new SchoolManagementService();
         final long school = schools.createSchool("School").getId();
-        schools.createGroup(school, new GroupDetails("Group", DanceGroupType.REGULAR, 0, 99, Set.of()));
+        populatedGroup(schools, school);
         final Show show = schools.createShow(
                 school,
                 "Show",
@@ -62,7 +62,7 @@ class SchedulingServiceTest {
     public @Test void concurrentRunIsRejectedWhileEditsRemainPossibleAndInvalidateTheFirstResult() throws Exception {
         final var schools = new SchoolManagementService();
         final long school = schools.createSchool("School").getId();
-        schools.createGroup(school, new GroupDetails("Group", DanceGroupType.REGULAR, 0, 99, Set.of()));
+        populatedGroup(schools, school);
         final Show show = schools.createShow(
                 school,
                 "Show",
@@ -84,7 +84,7 @@ class SchedulingServiceTest {
                         ManagementExceptionKind.CONFLICT,
                         assertThrows(ManagementException.class, () -> scheduling.schedule(school, show.getId()))
                                 .getKind());
-                schools.createGroup(school, new GroupDetails("New group", DanceGroupType.REGULAR, 0, 99, Set.of()));
+                populatedGroup(schools, school);
             } finally {
                 release.countDown();
             }
@@ -98,6 +98,16 @@ class SchedulingServiceTest {
         assertEquals(2, show.getDayParts().getFirst().getDanceGroups().size());
     }
 
+    private static void populatedGroup(final SchoolManagementService schools, final long school) {
+        final long group = schools.createGroup(
+                        school, new GroupDetails("Group", DanceGroupType.REGULAR, 0, 99, Set.of()))
+                .getId();
+        schools.addGroupDancer(
+                school,
+                group,
+                schools.createDancer(school, "Dancer", LocalDate.of(2000, 1, 1)).getId());
+    }
+
     private static SchedulingEngine blockingEngine(final CountDownLatch entered, final CountDownLatch release) {
         final SchedulingEngine engine = (final SchedulingInput input) -> {
             entered.countDown();