Fix HTMLDraftman.visitTriangle() - use sTriangle.hashCode() instead of this.hashCode()

The bug caused HTML class and CSS selector to have different IDs, breaking triangle rendering.

TESTING_HANDOFF.md

@@ -0,0 +1,388 @@
+# Testing Strategy Handoff Document
+
+**Project:** shapes - Java Shape Editor  
+**Date:** March 27, 2026  
+**Author:** AI Coding Orchestrator  
+
+---
+
+## 1. Problem Statement
+
+The objective was to explore the project, identify gaps in test coverage, and propose a testing strategy to improve code quality and reliability.
+
+### Initial Questions
+- What is the current test coverage?
+- What classes/packages are tested vs. untested?
+- What is the recommended testing approach moving forward?
+
+---
+
+## 2. Project Overview
+
+### Tech Stack
+- **Language:** Java 16
+- **Build Tool:** Maven
+- **Testing Framework:** JUnit 5 (Jupiter)
+- **Logging:** SLF4J + Logback
+
+### Package Structure
+```
+src/main/java/ovh/gasser/newshapes/
+├── App.java                    # Main application entry
+├── Selection.java              # Selection management
+├── ShapeVisitor.java           # Visitor interface
+├── SVGExporter.java            # SVG export logic
+├── HTMLExporter.java           # HTML export logic
+├── shapes/
+│   ├── Shape.java              # Shape interface
+│   ├── AbstractShape.java      # Base abstract class
+│   ├── SRectangle.java         # Rectangle shape
+│   ├── SCircle.java            # Circle shape
+│   ├── STriangle.java          # Triangle shape
+│   ├── SText.java              # Text shape
+│   ├── SCollection.java        # Shape collection (composite)
+│   └── ResizeHandle.java       # Resize handle enum
+├── attributes/
+│   ├── Attributes.java         # Base attributes interface
+│   ├── SelectionAttributes.java # Selection state
+│   └── ColorAttributes.java     # Fill/stroke colors
+├── ui/
+│   ├── Controller.java         # Main controller
+│   ├── ShapesView.java        # View component
+│   ├── ShapeDraftman.java     # Drawing component
+│   ├── listeners/
+│   │   ├── MenuAddListener.java
+│   │   ├── MenuEditListener.java
+│   │   └── SelectionListener.java
+│   └── visitors/
+│       ├── SVGDraftman.java    # SVG visitor implementation
+│       └── HTMLDraftman.java   # HTML visitor implementation
+└── util/
+    └── Streamable.java         # Stream support interface
+```
+
+---
+
+## 3. Initial Exploration Findings
+
+### 3.1 Existing Test Coverage (Before Work)
+
+| Test File | Coverage |
+|-----------|----------|
+| AbstractShapeTest.java | Partial (6 tests) |
+| SRectangleTest.java | ✅ |
+| SCircleTest.java | ✅ |
+| STriangleTest.java | ✅ |
+| STextTest.java | ✅ |
+| SVGExporterTest.java | ✅ |
+| HTMLExporterTest.java | ✅ |
+
+**Total: 36 tests across 7 test classes**
+
+### 3.2 Classes with NO Tests
+
+| Priority | Class | Reason for Testing Need |
+|----------|-------|------------------------|
+| 🔴 High | SCollection | Core composite pattern, child management, bounds calculation |
+| 🔴 High | Selection | Critical selection management, listener notifications |
+| 🔴 High | Streamable | Interface with default method used throughout |
+| 🟡 Medium | SelectionAttributes | Core data type |
+| 🟡 Medium | ColorAttributes | Core data type |
+| 🟡 Medium | SVGDraftman | Complex string generation |
+| 🟡 Medium | HTMLDraftman | Complex string generation |
+| 🟢 Low | Controller | UI logic, integration points |
+| 🟢 Low | ShapeDraftman | UI rendering |
+| 🟢 Low | ShapesView | UI component |
+
+### 3.3 Issues in Existing Tests
+
+1. **Shallow coverage** - Most shape tests only verify creation and bounds
+2. **No edge cases** - Missing: null handling, negative coordinates, zero dimensions
+3. **Reflection usage** - SCircleTest uses reflection to check color (fragile)
+4. **No contract tests** - Shape interface has no tests verifying invariants
+5. **Inconsistent clone testing** - Some tests verify deep copy, others don't
+
+---
+
+## 4. Work Completed
+
+### 4.1 Tests Added
+
+Three new test files created with 21 new tests:
+
+#### SCollectionTest.java (12 tests)
+```java
+src/test/java/ovh/gasser/newshapes/shapes/SCollectionTest.java
+```
+
+| Test Method | Purpose |
+|-------------|---------|
+| testCreateWithShapes | Verify SCollection.of() creates collection with shapes |
+| testAdd | Verify add() adds a shape to the collection |
+| testRemove | Verify remove() removes a shape from the collection |
+| testIterator | Verify iterator() iterates over children |
+| testStream | Verify stream() returns a stream of children |
+| testGetBoundsEmptyCollection | Verify getBounds() returns Rectangle(WIN_SIZE) when empty |
+| testGetBoundsWithChildren | Verify getBounds() returns union of all children's bounds |
+| testTranslate | Verify translate() moves all children |
+| testClone | Verify clone() creates deep copy with SelectionAttributes |
+| testToString | Verify toString() contains SCollection |
+| testAddAttributesPropagatesToChildren | Verify ColorAttributes are propagated to children |
+| testGetAttributesReturnsChildColor | Verify getAttributes(ColorAttributes.ID) returns first child's color |
+
+#### SelectionTest.java (7 tests)
+```java
+src/test/java/ovh/gasser/newshapes/SelectionTest.java
+```
+
+| Test Method | Purpose |
+|-------------|---------|
+| testIsEmptyInitially | Verify isEmpty() returns true initially |
+| testAdd | Verify add() adds shape and marks it selected |
+| testAddAll | Verify addAll() adds multiple shapes |
+| testClear | Verify clear() removes all shapes and marks them unselected |
+| testGetSelectedShapesReturnsCopy | Verify getSelectedShapes() returns immutable copy |
+| testAddListener | Verify addListener() and listener notification |
+| testNullAddAllDoesNothing | Verify addAll(null) doesn't throw |
+
+#### StreamableTest.java (2 tests)
+```java
+src/test/java/ovh/gasser/newshapes/util/StreamableTest.java
+```
+
+| Test Method | Purpose |
+|-------------|---------|
+| testStreamReturnsStreamOfElements | Verify stream() returns all elements |
+| testStreamEmptyCollection | Verify stream() works on empty collection |
+
+### 4.2 Test Results
+
+```
+Tests run: 57, Failures: 0, Errors: 0, Skipped: 0
+BUILD SUCCESS
+```
+
+---
+
+## 5. Oracle Strategic Review
+
+Consulted @oracle for architectural guidance on testing strategy.
+
+### 5.1 Assessment
+
+**Overall Grade: B- (Adequate but shallow)**
+
+| Area | Coverage | Quality |
+|------|----------|---------|
+| Shapes | ~60% | Basic happy-path only |
+| SCollection | Good | Decent coverage including edge cases |
+| Selection | Good | Tests core behavior + listeners |
+| Exporters | Good | Structure + format validation |
+| AbstractShape | Good | Tests polymorphic behavior |
+
+### 5.2 Recommended Priority
+
+| Priority | Area | Rationale |
+|----------|------|-----------|
+| P0 | Attributes tests | SelectionAttributes, ColorAttributes - core data types |
+| P1 | Visitor tests | SVGDraftman/HTMLDraftman - complex string generation |
+| P1 | contains(Point) | Critical hit-testing behavior |
+| P2 | UI tests | Controller integration points |
+| P2 | Edge cases | Zero dimensions, negative coords, null handling |
+| P3 | ResizeHandle | All 8 handles should be tested |
+
+### 5.3 CI/CD Recommendations
+
+1. **Add JaCoCo** - Enforce 80% code coverage
+2. **Parallel tests** - Enable parallel test execution in surefire
+3. **GitHub Actions** - Add CI pipeline
+
+---
+
+## 6. Visitor Testing Approach (@oracle)
+
+### 6.1 Why Direct Visitor Tests?
+
+Current exporter tests obscure visitor logic in the full pipeline. Direct tests provide:
+- **Isolation** - Tests fail at specific visitor method
+- **Faster feedback** - No complex shape construction needed
+- **Edge case targeting** - Test specific attribute combinations
+
+### 6.2 Recommended Structure
+
+```
+src/test/java/ovh/gasser/newshapes/ui/visitors/
+├── SVGDraftmanTest.java    # Direct visitor tests
+└── HTMLDraftmanTest.java
+```
+
+### 6.3 Assertions Strategy
+
+| Use Exact Match For | Use Contains/Partial For |
+|---------------------|---------------------------|
+| Element tags (`<rect>`, `<circle>`) | Dynamic values (coords, colors) |
+| Fixed attributes (xmlns, DOCTYPE) | CSS output ordering |
+| Structure markers | |
+
+### 6.4 Edge Cases to Cover
+
+- Null ColorAttributes
+- Filled only / stroked only / both / neither
+- Empty collections
+- Nested SCollection
+- Text font styles (ITALIC, BOLD, ITALIC+BOLD)
+
+### 6.5 Bug Found 🐛
+
+**HTMLDraftman.visitTriangle()** line 69:
+```java
+htmlOutput.printf("<div class=\"triangle%d\"></div>\n", this.hashCode()); // BUG
+```
+Should be `sTriangle.hashCode()`. Direct visitor tests would catch this.
+
+---
+
+## 7. Remaining Work
+
+### 7.1 High Priority
+
+| # | Task | Estimated Effort |
+|---|------|-----------------|
+| 1 | Add SelectionAttributes test | 1 hour |
+| 2 | Add ColorAttributes test | 1 hour |
+| 3 | Create ShapeContractTest (parameterized) | 2 hours |
+
+### 7.2 Medium Priority
+
+| # | Task | Estimated Effort |
+|---|------|-----------------|
+| 4 | Add SVGDraftmanTest | 2 hours |
+| 5 | Add HTMLDraftmanTest | 2 hours |
+| 6 | Add contains(Point) tests | 2-3 hours |
+
+### 7.3 Lower Priority
+
+| # | Task | Estimated Effort |
+|---|------|-----------------|
+| 7 | Add ResizeHandle tests | 1 hour |
+| 8 | Add edge case tests (null, negative, zero) | 2 hours |
+| 9 | Fix HTMLDraftman.visitTriangle() bug | 30 min |
+| 10 | Set up JaCoCo + CI | 1 hour |
+
+---
+
+## 8. Appendix
+
+### A. Current Test Files
+
+```
+src/test/java/ovh/gasser/newshapes/
+├── shapes/
+│   ├── AbstractShapeTest.java      # 6 tests
+│   ├── SRectangleTest.java         # 4 tests
+│   ├── SCircleTest.java            # 5 tests
+│   ├── STriangleTest.java          # 3 tests
+│   ├── STextTest.java              # 5 tests
+│   └── SCollectionTest.java        # 12 tests (NEW)
+├── exporters/
+│   ├── SVGExporterTest.java        # 7 tests
+│   └── HTMLExporterTest.java        # 6 tests
+├── SelectionTest.java              # 7 tests (NEW)
+└── util/
+    └── StreamableTest.java          # 2 tests (NEW)
+```
+
+### B. Maven Dependencies
+
+```xml
+<dependency>
+    <groupId>org.junit.jupiter</groupId>
+    <artifactId>junit-jupiter-api</artifactId>
+    <version>5.10.0</version>
+    <scope>test</scope>
+</dependency>
+<dependency>
+    <groupId>org.junit.jupiter</groupId>
+    <artifactId>junit-jupiter-engine</artifactId>
+    <version>5.10.0</version>
+    <scope>test</scope>
+</dependency>
+```
+
+### C. JaCoCo Configuration (Recommended)
+
+```xml
+<plugin>
+    <groupId>org.jacoco</groupId>
+    <artifactId>jacoco-maven-plugin</artifactId>
+    <version>0.8.11</version>
+    <executions>
+        <execution>
+            <goals>
+                <goal>prepare-agent</goal>
+                <goal>report</goal>
+                <goal>check</goal>
+            </goals>
+        </execution>
+    </executions>
+    <configuration>
+        <rules>
+            <rule>
+                <element>CLASS</element>
+                <limits>
+                    <limit>
+                        <counter>LINE</counter>
+                        <value>COVEREDRATIO</value>
+                        <minimum>0.80</minimum>
+                    </limit>
+                </limits>
+            </rule>
+        </rules>
+    </configuration>
+</plugin>
+```
+
+### D. Shape Contract Test (Recommended Pattern)
+
+```java
+class ShapeContractTest {
+    @ParameterizedTest
+    @MethodSource("ovh.gasser.newshapes.shapes.ShapeFactory#allShapes")
+    void testCloneIsIndependent(Shape s) { ... }
+    
+    @ParameterizedTest
+    @MethodSource("ovh.gasser.newshapes.shapes.ShapeFactory#allShapes")
+    void testGetBoundsReturnsCopy(Shape s) { ... }
+    
+    @ParameterizedTest
+    @MethodSource("ovh.gasser.newshapes.shapes.ShapeFactory#allShapes")
+    void testTranslateMutatesInPlace(Shape s) { ... }
+}
+```
+
+---
+
+## 9. Summary
+
+| Metric | Before | After |
+|--------|--------|-------|
+| Total Tests | 36 | 57 |
+| Test Classes | 7 | 10 |
+| Core Classes Tested | 8 | 11 |
+| Coverage Grade | C | B- |
+
+**Key Achievements:**
+- Identified and filled gaps in core business logic (SCollection, Selection, Streamable)
+- Received architectural guidance from @oracle
+- Discovered potential bug in HTMLDraftman
+- Established clear roadmap for remaining work
+
+**Next Steps:**
+1. Add Attributes tests (SelectionAttributes, ColorAttributes)
+2. Add visitor tests (SVGDraftman, HTMLDraftman)
+3. Add Shape contract tests
+4. Set up CI/CD with JaCoCo coverage gate
+
+---
+
+*End of Handoff Document*

src/main/java/ovh/gasser/newshapes/ui/visitors/HTMLDraftman.java

@@ -66,11 +66,11 @@ public class HTMLDraftman implements ShapeVisitor {
 
     @Override
     public void visitTriangle(STriangle sTriangle) {
-        htmlOutput.printf("<div class=\"triangle%d\"></div>\n", this.hashCode());
+        htmlOutput.printf("<div class=\"triangle%d\"></div>\n", sTriangle.hashCode());
         var bounds = sTriangle.getBounds();
         ColorAttributes colAttrs = (ColorAttributes) sTriangle.getAttributes(ColorAttributes.ID);
         String colorString = formatCSSColor(colAttrs.filledColor);
-        StringJoiner joiner = new StringJoiner("\n", ".triangle%d{\n".formatted(this.hashCode()), "\n}\n");
+        StringJoiner joiner = new StringJoiner("\n", ".triangle%d{\n".formatted(sTriangle.hashCode()), "\n}\n");
         joiner.add("  position: absolute;");
         joiner.add("  top: %dpx;".formatted(bounds.y));
         joiner.add("  left: %dpx;".formatted(bounds.x));

src/test/java/ovh/gasser/newshapes/SelectionTest.java

@@ -0,0 +1,144 @@
+package ovh.gasser.newshapes;
+
+import org.junit.jupiter.api.Test;
+import ovh.gasser.newshapes.attributes.SelectionAttributes;
+import ovh.gasser.newshapes.shapes.SCircle;
+import ovh.gasser.newshapes.shapes.SRectangle;
+import ovh.gasser.newshapes.shapes.STriangle;
+import ovh.gasser.newshapes.ui.listeners.SelectionListener;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.List;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class SelectionTest {
+
+    @Test
+    void testIsEmptyInitially() {
+        Selection selection = new Selection();
+        assertTrue(selection.isEmpty());
+    }
+
+    @Test
+    void testAdd() {
+        Selection selection = new Selection();
+        SCircle circle = SCircle.create(0, 0, 50);
+
+        selection.add(circle);
+
+        assertFalse(selection.isEmpty());
+        assertEquals(1, selection.getSelectedShapes().size());
+        assertTrue(selection.getSelectedShapes().contains(circle));
+
+        // Verify shape is marked as selected
+        SelectionAttributes attrs = (SelectionAttributes) circle.getAttributes(SelectionAttributes.ID);
+        assertNotNull(attrs);
+        assertTrue(attrs.selected);
+    }
+
+    @Test
+    void testAddAll() {
+        Selection selection = new Selection();
+        SCircle circle1 = SCircle.create(0, 0, 50);
+        SRectangle rect = SRectangle.create(10, 10, 100, 50);
+        STriangle triangle = STriangle.create(50, 50, 30, java.awt.Color.BLACK, java.awt.Color.BLACK);
+
+        List<ovh.gasser.newshapes.shapes.Shape> shapes = Arrays.asList(circle1, rect, triangle);
+        selection.addAll(shapes);
+
+        assertEquals(3, selection.getSelectedShapes().size());
+        assertTrue(selection.getSelectedShapes().contains(circle1));
+        assertTrue(selection.getSelectedShapes().contains(rect));
+        assertTrue(selection.getSelectedShapes().contains(triangle));
+    }
+
+    @Test
+    void testClear() {
+        Selection selection = new Selection();
+        SCircle circle = SCircle.create(0, 0, 50);
+        SRectangle rect = SRectangle.create(10, 10, 100, 50);
+
+        selection.add(circle);
+        selection.add(rect);
+
+        assertFalse(selection.isEmpty());
+        assertEquals(2, selection.getSelectedShapes().size());
+
+        selection.clear();
+
+        assertTrue(selection.isEmpty());
+        assertEquals(0, selection.getSelectedShapes().size());
+
+        // Verify shapes are marked as unselected
+        SelectionAttributes circleAttrs = (SelectionAttributes) circle.getAttributes(SelectionAttributes.ID);
+        SelectionAttributes rectAttrs = (SelectionAttributes) rect.getAttributes(SelectionAttributes.ID);
+
+        assertNotNull(circleAttrs);
+        assertNotNull(rectAttrs);
+        assertFalse(circleAttrs.selected);
+        assertFalse(rectAttrs.selected);
+    }
+
+    @Test
+    void testGetSelectedShapesReturnsCopy() {
+        Selection selection = new Selection();
+        SCircle circle = SCircle.create(0, 0, 50);
+        selection.add(circle);
+
+        List<ovh.gasser.newshapes.shapes.Shape> copy = selection.getSelectedShapes();
+
+        // Try to modify the copy
+        assertThrows(UnsupportedOperationException.class, () -> copy.add(SCircle.create(10, 10, 20)));
+
+        // Original should be unchanged
+        assertEquals(1, selection.getSelectedShapes().size());
+    }
+
+    @Test
+    void testAddListener() {
+        Selection selection = new Selection();
+        AtomicBoolean listenerNotified = new AtomicBoolean(false);
+        AtomicInteger notificationCount = new AtomicInteger(0);
+
+        SelectionListener listener = (selectedShapes) -> {
+            listenerNotified.set(true);
+            notificationCount.incrementAndGet();
+        };
+
+        selection.addListener(listener);
+
+        // Adding a shape should notify listener
+        SCircle circle = SCircle.create(0, 0, 50);
+        selection.add(circle);
+
+        assertTrue(listenerNotified.get());
+        assertEquals(1, notificationCount.get());
+
+        // Adding another shape should notify listener again
+        SRectangle rect = SRectangle.create(10, 10, 100, 50);
+        selection.add(rect);
+
+        assertEquals(2, notificationCount.get());
+
+        // Clearing should notify listener
+        selection.clear();
+
+        assertEquals(3, notificationCount.get());
+    }
+
+    @Test
+    void testNullAddAllDoesNothing() {
+        Selection selection = new Selection();
+
+        // Should not throw
+        assertDoesNotThrow(() -> selection.addAll(null));
+
+        // Selection should still be empty
+        assertTrue(selection.isEmpty());
+    }
+}

src/test/java/ovh/gasser/newshapes/shapes/SCollectionTest.java

@@ -0,0 +1,176 @@
+package ovh.gasser.newshapes.shapes;
+
+import org.junit.jupiter.api.Test;
+import ovh.gasser.newshapes.App;
+import ovh.gasser.newshapes.attributes.ColorAttributes;
+import ovh.gasser.newshapes.attributes.SelectionAttributes;
+
+import java.awt.Color;
+import java.awt.Rectangle;
+import java.util.Iterator;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class SCollectionTest {
+
+    @Test
+    void testCreateWithShapes() {
+        SRectangle rect = SRectangle.create(10, 20, 100, 50);
+        SCircle circle = SCircle.create(50, 50, 25);
+        
+        SCollection collection = SCollection.of(rect, circle);
+        
+        assertNotNull(collection);
+        assertEquals(2, collection.stream().count());
+    }
+
+    @Test
+    void testAdd() {
+        SCollection collection = SCollection.of();
+        SRectangle rect = SRectangle.create(10, 20, 100, 50);
+        
+        collection.add(rect);
+        
+        assertEquals(1, collection.stream().count());
+        assertSame(rect, collection.iterator().next());
+    }
+
+    @Test
+    void testRemove() {
+        SRectangle rect = SRectangle.create(10, 20, 100, 50);
+        SCollection collection = SCollection.of(rect);
+        
+        collection.remove(rect);
+        
+        assertEquals(0, collection.stream().count());
+    }
+
+    @Test
+    void testIterator() {
+        SRectangle rect1 = SRectangle.create(10, 20, 100, 50);
+        SRectangle rect2 = SRectangle.create(30, 40, 60, 70);
+        SCollection collection = SCollection.of(rect1, rect2);
+        
+        Iterator<Shape> iterator = collection.iterator();
+        
+        assertTrue(iterator.hasNext());
+        assertSame(rect1, iterator.next());
+        assertTrue(iterator.hasNext());
+        assertSame(rect2, iterator.next());
+        assertFalse(iterator.hasNext());
+    }
+
+    @Test
+    void testStream() {
+        SRectangle rect1 = SRectangle.create(10, 20, 100, 50);
+        SRectangle rect2 = SRectangle.create(30, 40, 60, 70);
+        SCircle circle = SCircle.create(50, 50, 25);
+        SCollection collection = SCollection.of(rect1, rect2, circle);
+        
+        List<Shape> shapes = collection.stream().collect(Collectors.toList());
+        
+        assertEquals(3, shapes.size());
+        assertTrue(shapes.contains(rect1));
+        assertTrue(shapes.contains(rect2));
+        assertTrue(shapes.contains(circle));
+    }
+
+    @Test
+    void testGetBoundsEmptyCollection() {
+        SCollection collection = SCollection.of();
+        
+        Rectangle bounds = collection.getBounds();
+        
+        assertEquals(App.WIN_SIZE.width, bounds.width);
+        assertEquals(App.WIN_SIZE.height, bounds.height);
+    }
+
+    @Test
+    void testGetBoundsWithChildren() {
+        SRectangle rect1 = SRectangle.create(10, 10, 50, 50);
+        SRectangle rect2 = SRectangle.create(100, 100, 80, 40);
+        SCollection collection = SCollection.of(rect1, rect2);
+        
+        Rectangle bounds = collection.getBounds();
+        
+        // Union should cover from (10,10) to (180,140)
+        assertEquals(10, bounds.x);
+        assertEquals(10, bounds.y);
+        assertEquals(170, bounds.width);  // 100+80-10 = 170
+        assertEquals(130, bounds.height); // 100+40-10 = 130
+    }
+
+    @Test
+    void testTranslate() {
+        SRectangle rect = SRectangle.create(10, 20, 100, 50);
+        SCollection collection = SCollection.of(rect);
+        
+        collection.translate(5, 10);
+        
+        Rectangle bounds = rect.getBounds();
+        assertEquals(15, bounds.x);
+        assertEquals(30, bounds.y);
+    }
+
+    @Test
+    void testClone() {
+        SRectangle rect = SRectangle.create(10, 20, 100, 50);
+        SCollection original = SCollection.of(rect);
+        
+        SCollection cloned = (SCollection) original.clone();
+        
+        assertNotSame(original, cloned);
+        assertEquals(original.stream().count(), cloned.stream().count());
+        
+        // Verify SelectionAttributes is added to clone
+        assertNotNull(cloned.getAttributes(SelectionAttributes.ID));
+        
+        // Verify deep copy - modifying clone doesn't affect original
+        Iterator<Shape> clonedIterator = cloned.iterator();
+        Shape clonedChild = clonedIterator.next();
+        clonedChild.translate(100, 100);
+        
+        Rectangle originalBounds = rect.getBounds();
+        assertEquals(10, originalBounds.x);
+        assertEquals(20, originalBounds.y);
+    }
+
+    @Test
+    void testToString() {
+        SCollection collection = SCollection.of();
+        
+        String str = collection.toString();
+        
+        assertTrue(str.contains("SCollection"));
+    }
+
+    @Test
+    void testAddAttributesPropagatesToChildren() {
+        SRectangle rect = SRectangle.create(10, 20, 100, 50);
+        SCollection collection = SCollection.of(rect);
+        
+        ColorAttributes attrs = new ColorAttributes(true, true, Color.RED, Color.BLUE);
+        collection.addAttributes(attrs);
+        
+        ColorAttributes childAttrs = (ColorAttributes) rect.getAttributes(ColorAttributes.ID);
+        
+        assertNotNull(childAttrs);
+        assertEquals(Color.RED, childAttrs.filledColor);
+        assertEquals(Color.BLUE, childAttrs.strokedColor);
+    }
+
+    @Test
+    void testGetAttributesReturnsChildColor() {
+        SRectangle rect = SRectangle.create(10, 20, 100, 50, Color.GREEN);
+        SCircle circle = SCircle.create(50, 50, 25);
+        SCollection collection = SCollection.of(rect, circle);
+        
+        ColorAttributes attrs = (ColorAttributes) collection.getAttributes(ColorAttributes.ID);
+        
+        assertNotNull(attrs);
+        // First child's color should be returned (strokedColor for SRectangle)
+        assertEquals(Color.GREEN, attrs.strokedColor);
+    }
+}

src/test/java/ovh/gasser/newshapes/util/StreamableTest.java

@@ -0,0 +1,48 @@
+package ovh.gasser.newshapes.util;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.Stream;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class StreamableTest {
+
+    private static class TestStreamable implements Streamable<String> {
+        private final List<String> elements;
+
+        TestStreamable(List<String> elements) {
+            this.elements = new ArrayList<>(elements);
+        }
+
+        @Override
+        public java.util.Iterator<String> iterator() {
+            return elements.iterator();
+        }
+    }
+
+    @Test
+    void testStreamReturnsStreamOfElements() {
+        List<String> testData = Arrays.asList("a", "b", "c");
+        Streamable<String> streamable = new TestStreamable(testData);
+
+        Stream<String> result = streamable.stream();
+
+        assertNotNull(result);
+        assertEquals(testData, result.toList());
+    }
+
+    @Test
+    void testStreamEmptyCollection() {
+        List<String> emptyData = new ArrayList<>();
+        Streamable<String> streamable = new TestStreamable(emptyData);
+
+        Stream<String> result = streamable.stream();
+
+        assertNotNull(result);
+        assertTrue(result.toList().isEmpty());
+    }
+}