test(engine): share the rectangle, L-shape and arc-part fixtures

Engine tests drew the same rectangle, square, L-shape and arc part in
private helpers across the Expander, golden-layout, fill-stack and
fixed-strategy tests. They now use TestDrawingFactory; files whose
helper had its own default size keep a one-line wrapper for it.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

OpenNest.Engine.Tests/Fill/ExpanderCutoffDeltaTests.cs

@@ -1,6 +1,7 @@
 using OpenNest.CNC;
 using OpenNest.Converters;
 using OpenNest.Engine.Fill;
+using OpenNest.Engine.Tests.Jobs;
 using OpenNest.Geometry;
 using Xunit;
 
@@ -10,16 +11,8 @@ public class ExpanderCutoffDeltaTests
 {
     private static Plate Sheet() => new(new Size(30, 30)) { EdgeSpacing = new Spacing(0, 0) };
 
-    private static Program Rectangle(double width = 2, double height = 2)
-    {
-        var program = new Program();
-        program.MoveTo(0, 0);
-        program.LineTo(width, 0);
-        program.LineTo(width, height);
-        program.LineTo(0, height);
-        program.LineTo(0, 0);
-        return program;
-    }
+    private static Program Rectangle(double width = 2, double height = 2) =>
+        TestDrawingFactory.Rectangle(width, height);
 
     private static Part Add(Plate plate, Program program, double x, double y)
     {

OpenNest.Engine.Tests/Fill/ExpanderCutoffQuadrantTests.cs

@@ -1,5 +1,6 @@
 using OpenNest.CNC;
 using OpenNest.Engine.Fill;
+using OpenNest.Engine.Tests.Jobs;
 using OpenNest.Geometry;
 using Xunit;
 
@@ -7,17 +8,6 @@ namespace OpenNest.Engine.Tests.Fill;
 
 public class ExpanderCutoffQuadrantTests
 {
-    private static Program Square()
-    {
-        var program = new Program();
-        program.MoveTo(0, 0);
-        program.LineTo(2, 0);
-        program.LineTo(2, 2);
-        program.LineTo(0, 2);
-        program.LineTo(0, 0);
-        return program;
-    }
-
     public static IEnumerable<object[]> Cases()
     {
         foreach (var quadrant in new[] { 1, 2, 3, 4 })
@@ -42,8 +32,9 @@ public class ExpanderCutoffQuadrantTests
             quadrant == 3 || quadrant == 4 ? -80 : 0);
         var anchorPose = origin + new Vector(30, 30);
         var moverPose = anchorPose + (verticalMotion ? new Vector(0, -3) : new Vector(-3, 0));
-        var anchor = new Part(new Drawing("anchor", Square()), anchorPose);
-        var mover = new Part(new Drawing("mover", Square()), moverPose);
+        var anchor = new Part(
+            new Drawing("anchor", TestDrawingFactory.Rectangle(2, 2)), anchorPose);
+        var mover = new Part(new Drawing("mover", TestDrawingFactory.Rectangle(2, 2)), moverPose);
         plate.Parts.Add(anchor);
         plate.Parts.Add(mover);
 

OpenNest.Engine.Tests/Fill/ExpanderFinalQualityTests.cs

@@ -2,6 +2,7 @@ using System.Collections.Generic;
 using OpenNest.CNC;
 using OpenNest.Converters;
 using OpenNest.Engine.Fill;
+using OpenNest.Engine.Tests.Jobs;
 using OpenNest.Geometry;
 using Xunit;
 
@@ -14,17 +15,6 @@ public class ExpanderFinalQualityTests
     private static Program Disk(double radius) =>
         ConvertGeometry.ToProgram(new List<Entity> { new Circle(0, 0, radius) });
 
-    private static Program Rectangle(double width, double height)
-    {
-        var program = new Program();
-        program.MoveTo(0, 0);
-        program.LineTo(width, 0);
-        program.LineTo(width, height);
-        program.LineTo(0, height);
-        program.LineTo(0, 0);
-        return program;
-    }
-
     private static Part Add(Plate plate, Program program, double x, double y)
     {
         var part = new Part(new Drawing("neutral", program), new Vector(x, y));
@@ -56,7 +46,7 @@ public class ExpanderFinalQualityTests
     {
         var plate = Sheet();
         Add(plate, Disk(2), 10, 6);
-        var mover = Add(plate, Rectangle(1, 1), 12, 5.5);
+        var mover = Add(plate, TestDrawingFactory.Rectangle(1, 1), 12, 5.5);
         var result = Expander.Separate(new List<Part> { mover }, plate, spacing: 1);
         Assert.True(result.Converged, $"curved contact pinned: {result.Violations.Count} violations");
         Assert.True(result.Positions[0].X >= 13 - 1e-3);
@@ -79,7 +69,7 @@ public class ExpanderFinalQualityTests
         program.LineTo(0, 6 * k);
         program.LineTo(0, 0);
         Add(plate, program, 10, 5);
-        var mover = Add(plate, Rectangle(2 * k, 2 * k), 10 + k, 5 + 3 * k);
+        var mover = Add(plate, TestDrawingFactory.Rectangle(2 * k, 2 * k), 10 + k, 5 + 3 * k);
         // Left finger [10,10.0002] × [5.0002,5.0006] intersects the
         // mover [10.0001,10.0003] × [5.0003,5.0005] in positive area.
         var result = Expander.Separate(new List<Part> { mover }, plate, 0);
@@ -92,8 +82,8 @@ public class ExpanderFinalQualityTests
     public void Expand_RemoteRegeneratedCutoff_MustNotPinUnrelatedGrowth()
     {
         var plate = Sheet();
-        var anchor = Add(plate, Rectangle(2, 2), 1, 4);
-        var mover = Add(plate, Rectangle(2, 2), 4, 4);
+        var anchor = Add(plate, TestDrawingFactory.Rectangle(2, 2), 1, 4);
+        var mover = Add(plate, TestDrawingFactory.Rectangle(2, 2), 4, 4);
         plate.CutOffs.Add(new CutOff(new Vector(0, 10), CutOffAxis.Horizontal));
         var settings = new CutOffSettings();
         plate.RegenerateCutOffs(settings);
@@ -114,8 +104,8 @@ public class ExpanderFinalQualityTests
     public void Expand_RegeneratedCutoffBlocksCrossingEvenWithClearFarEndpoint()
     {
         var plate = new Plate(new Size(20, 30)) { EdgeSpacing = new Spacing(0, 0) };
-        var anchor = Add(plate, Rectangle(2, 2), 1, 1);
-        var mover = Add(plate, Rectangle(2, 2), 1, 6);
+        var anchor = Add(plate, TestDrawingFactory.Rectangle(2, 2), 1, 1);
+        var mover = Add(plate, TestDrawingFactory.Rectangle(2, 2), 1, 6);
         plate.CutOffs.Add(new CutOff(new Vector(0, 10), CutOffAxis.Horizontal));
         var settings = new CutOffSettings();
         plate.RegenerateCutOffs(settings);
@@ -134,8 +124,8 @@ public class ExpanderFinalQualityTests
     public void Expand_OutsideUnchangedMover_MustNotReturnUnqualifiedSuccess()
     {
         var plate = Sheet();
-        var anchor = Add(plate, Rectangle(2, 2), 1, 4);
-        var mover = Add(plate, Rectangle(2, 2), 35, 4);
+        var anchor = Add(plate, TestDrawingFactory.Rectangle(2, 2), 1, 4);
+        var mover = Add(plate, TestDrawingFactory.Rectangle(2, 2), 35, 4);
         var result = Expander.Expand(new List<Part> { anchor, mover }, plate,
             new Expander.Options { MaxSpacing = 3 });
 

OpenNest.Engine.Tests/Fill/ExpanderIntersectingOpenPathTests.cs

@@ -1,5 +1,6 @@
 using OpenNest.CNC;
 using OpenNest.Engine.Fill;
+using OpenNest.Engine.Tests.Jobs;
 using OpenNest.Geometry;
 using Xunit;
 
@@ -7,17 +8,6 @@ namespace OpenNest.Engine.Tests.Fill;
 
 public class ExpanderIntersectingOpenPathTests
 {
-    private static Program Square()
-    {
-        var program = new Program();
-        program.MoveTo(0, 0);
-        program.LineTo(2, 0);
-        program.LineTo(2, 2);
-        program.LineTo(0, 2);
-        program.LineTo(0, 0);
-        return program;
-    }
-
     public static IEnumerable<object[]> Cases()
     {
         foreach (var quadrant in new[] { 1, 2, 3, 4 })
@@ -40,8 +30,8 @@ public class ExpanderIntersectingOpenPathTests
         };
         var expectedA = origin + Swap(40, 40);
         var expectedB = origin + Swap(43, 40);
-        var anchor = new Part(new Drawing("anchor", Square()), expectedA);
-        var mover = new Part(new Drawing("mover", Square()), expectedB);
+        var anchor = new Part(new Drawing("anchor", TestDrawingFactory.Rectangle(2, 2)), expectedA);
+        var mover = new Part(new Drawing("mover", TestDrawingFactory.Rectangle(2, 2)), expectedB);
         plate.Parts.Add(anchor);
         plate.Parts.Add(mover);
 

OpenNest.Engine.Tests/Fill/ExpanderQualityReviewTests.cs

@@ -1,6 +1,7 @@
 using System.Collections.Generic;
 using OpenNest.CNC;
 using OpenNest.Engine.Fill;
+using OpenNest.Engine.Tests.Jobs;
 using OpenNest.Geometry;
 using Xunit;
 
@@ -8,20 +9,10 @@ namespace OpenNest.Engine.Tests.Fill;
 
 public class ExpanderQualityReviewTests
 {
-    private static Program Rectangle(double width, double height)
-    {
-        var program = new Program();
-        program.MoveTo(0, 0);
-        program.LineTo(width, 0);
-        program.LineTo(width, height);
-        program.LineTo(0, height);
-        program.LineTo(0, 0);
-        return program;
-    }
-
     private static Part AddSquare(Plate plate, double x, double y, double size)
     {
-        var part = new Part(new Drawing("neutral", Rectangle(size, size)), new Vector(x, y));
+        var part = new Part(
+            new Drawing("neutral", TestDrawingFactory.Rectangle(size, size)), new Vector(x, y));
         plate.Parts.Add(part);
         return part;
     }
@@ -54,7 +45,7 @@ public class ExpanderQualityReviewTests
     {
         var plate = MakePlate(30);
         plate.ClampZones.Add(new ClampZone("tiny", new Box(5, 5, 1e-5, 1e-5)));
-        var frameProgram = Rectangle(10, 10);
+        var frameProgram = TestDrawingFactory.Rectangle(10, 10);
         frameProgram.MoveTo(4, 4);
         frameProgram.LineTo(6, 4);
         frameProgram.LineTo(6, 6);

OpenNest.Engine.Tests/Fill/ExpanderRemoteObliquePathTests.cs

@@ -1,5 +1,6 @@
 using OpenNest.CNC;
 using OpenNest.Engine.Fill;
+using OpenNest.Engine.Tests.Jobs;
 using OpenNest.Geometry;
 using Xunit;
 
@@ -7,17 +8,6 @@ namespace OpenNest.Engine.Tests.Fill;
 
 public class ExpanderRemoteObliquePathTests
 {
-    private static Program Square()
-    {
-        var program = new Program();
-        program.MoveTo(0, 0);
-        program.LineTo(2, 0);
-        program.LineTo(2, 2);
-        program.LineTo(0, 2);
-        program.LineTo(0, 0);
-        return program;
-    }
-
     public static IEnumerable<object[]> Cases()
     {
         foreach (var quadrant in new[] { 1, 2, 3, 4 })
@@ -42,8 +32,9 @@ public class ExpanderRemoteObliquePathTests
         };
         var anchorPose = origin + Swap(40, 40);
         var moverPose = origin + Swap(43, 40);
-        var anchor = new Part(new Drawing("anchor", Square()), anchorPose);
-        var mover = new Part(new Drawing("mover", Square()), moverPose);
+        var anchor = new Part(
+            new Drawing("anchor", TestDrawingFactory.Rectangle(2, 2)), anchorPose);
+        var mover = new Part(new Drawing("mover", TestDrawingFactory.Rectangle(2, 2)), moverPose);
         plate.Parts.Add(anchor);
         plate.Parts.Add(mover);
         if (cutoff)

OpenNest.Engine.Tests/Fill/ExpanderTests.cs

@@ -4,6 +4,7 @@ using System.Linq;
 using System.Threading;
 using OpenNest.CNC;
 using OpenNest.Engine.Fill;
+using OpenNest.Engine.Tests.Jobs;
 using OpenNest.Geometry;
 using Xunit;
 
@@ -15,16 +16,8 @@ namespace OpenNest.Engine.Tests.Fill;
 /// </summary>
 public class ExpanderTests
 {
-    private static Program Rectangle(double width = 4, double length = 4)
-    {
-        var program = new Program();
-        program.MoveTo(0, 0);
-        program.LineTo(width, 0);
-        program.LineTo(width, length);
-        program.LineTo(0, length);
-        program.LineTo(0, 0);
-        return program;
-    }
+    private static Program Rectangle(double width = 4, double length = 4) =>
+        TestDrawingFactory.Rectangle(width, length);
 
     private static Part AddSquare(Plate plate, double x, double y, double size = 4)
     {

OpenNest.Engine.Tests/Jobs/FillStackCharacterizationTests.cs

@@ -34,19 +34,6 @@ namespace OpenNest.Engine.Tests.Jobs;
 /// </remarks>
 public class FillStackCharacterizationTests
 {
-    private static Program LShape()
-    {
-        var program = new Program();
-        program.MoveTo(0, 0);
-        program.LineTo(6, 0);
-        program.LineTo(6, 4);
-        program.LineTo(3, 4);
-        program.LineTo(3, 2);
-        program.LineTo(0, 2);
-        program.LineTo(0, 0);
-        return program;
-    }
-
     /// <summary>6x4 block with a 2x2 notch cut into the middle of its top edge.</summary>
     private static Program Notched()
     {
@@ -63,18 +50,6 @@ public class FillStackCharacterizationTests
         return program;
     }
 
-    /// <summary>D-shape: 3x5 block closed by a semicircular arc.</summary>
-    private static Program ArcPart()
-    {
-        var program = new Program();
-        program.MoveTo(0, 0);
-        program.LineTo(3, 0);
-        program.ArcTo(3, 5, 3, 2.5, RotationType.CCW);
-        program.LineTo(0, 5);
-        program.LineTo(0, 0);
-        return program;
-    }
-
     /// <summary>
     /// 46 x 3 bar with a stepped end: irregular, and too long for the 48 x 28 work area at all
     /// but the sweep angles near 0 and 180 degrees, so only those prove productive and get learned.
@@ -112,9 +87,9 @@ public class FillStackCharacterizationTests
     private static Program Shape(string name) =>
         name switch
         {
-            "lshape" => LShape(),
+            "lshape" => TestDrawingFactory.LShape(),
             "notched" => Notched(),
-            "arc" => ArcPart(),
+            "arc" => TestDrawingFactory.ArcPart(),
             "bar" => LongBar(),
             "chevron" => Chevron(),
             _ => TestDrawingFactory.Rectangle(4, 3),
@@ -259,9 +234,9 @@ public class FillStackCharacterizationTests
     /// </summary>
     private static List<NestItem> MixedItems() =>
         [
-            new() { Drawing = new Drawing("lshape", LShape()), Quantity = 14 },
+            new() { Drawing = new Drawing("lshape", TestDrawingFactory.LShape()), Quantity = 14 },
             new() { Drawing = new Drawing("notched", Notched()), Quantity = 9 },
-            new() { Drawing = new Drawing("arc", ArcPart()), Quantity = 11 },
+            new() { Drawing = new Drawing("arc", TestDrawingFactory.ArcPart()), Quantity = 11 },
             new() { Drawing = new Drawing("rect", TestDrawingFactory.Rectangle(4, 3)), Quantity = 1 },
         ];
 
@@ -354,7 +329,11 @@ public class FillStackCharacterizationTests
         {
             var plate = MakeClampedPlate();
             // A quantity close to a full sheet makes clamp-dropped copies trigger refills.
-            var item = new NestItem { Drawing = new Drawing("lshape", LShape()), Quantity = 40 };
+            var item = new NestItem
+            {
+                Drawing = new Drawing("lshape", TestDrawingFactory.LShape()),
+                Quantity = 40,
+            };
             return Layout(
                 PlateFillService.FillItem(
                     strategy,

OpenNest.Engine.Tests/Jobs/FixedStrategyNestingEngineTests.cs

@@ -58,19 +58,6 @@ public class FixedStrategyNestingEngineTests
         Assert.Throws<ArgumentException>(() => new FixedStrategyNestingEngine("  "));
     }
 
-    private static Program LShape()
-    {
-        var program = new Program();
-        program.MoveTo(0, 0);
-        program.LineTo(6, 0);
-        program.LineTo(6, 4);
-        program.LineTo(3, 4);
-        program.LineTo(3, 2);
-        program.LineTo(0, 2);
-        program.LineTo(0, 0);
-        return program;
-    }
-
     public static TheoryData<string, string, double, int> LockedRotationCases =>
         new()
         {
@@ -99,7 +86,7 @@ public class FixedStrategyNestingEngineTests
             "rect-6x4" => TestDrawingFactory.Rectangle(6, 4),
             "rect-20x3" => TestDrawingFactory.Rectangle(20, 3),
             "rect-3x20" => TestDrawingFactory.Rectangle(3, 20),
-            _ => LShape(),
+            _ => TestDrawingFactory.LShape(),
         };
         var part = new NestJobPart(
             shape,

OpenNest.Engine.Tests/Jobs/GoldenLayoutTests.cs

@@ -29,41 +29,6 @@ public class GoldenLayoutTests
 {
     private const double PoseTolerance = 1e-9;
 
-    private static Program Rect(double width, double length)
-    {
-        var program = new Program();
-        program.MoveTo(0, 0);
-        program.LineTo(width, 0);
-        program.LineTo(width, length);
-        program.LineTo(0, length);
-        program.LineTo(0, 0);
-        return program;
-    }
-
-    private static Program LShape()
-    {
-        var program = new Program();
-        program.MoveTo(0, 0);
-        program.LineTo(6, 0);
-        program.LineTo(6, 4);
-        program.LineTo(3, 4);
-        program.LineTo(3, 2);
-        program.LineTo(0, 2);
-        program.LineTo(0, 0);
-        return program;
-    }
-
-    private static Program ArcPart()
-    {
-        var program = new Program();
-        program.MoveTo(0, 0);
-        program.LineTo(3, 0);
-        program.ArcTo(3, 5, 3, 2.5, RotationType.CCW);
-        program.LineTo(0, 5);
-        program.LineTo(0, 0);
-        return program;
-    }
-
     private static NestJobPart Part(string id, Program program, int quantity) =>
         new(id, PartGeometrySnapshot.FromProgram(program), quantity);
 
@@ -72,10 +37,10 @@ public class GoldenLayoutTests
         new(
             new[]
             {
-                Part("rect-a", Rect(6, 4), 8),
-                Part("rect-b", Rect(4, 3), 6),
-                Part("lshape", LShape(), 3),
-                Part("arc", ArcPart(), 3),
+                Part("rect-a", TestDrawingFactory.Rectangle(6, 4), 8),
+                Part("rect-b", TestDrawingFactory.Rectangle(4, 3), 6),
+                Part("lshape", TestDrawingFactory.LShape(), 3),
+                Part("arc", TestDrawingFactory.ArcPart(), 3),
             },
             new[] { new NestPlateStock("stock", new Size(30, 50), 5, 1, new Spacing(1, 1, 1, 1)) },
             new NestJobOptions(strategy)
@@ -86,9 +51,9 @@ public class GoldenLayoutTests
         new(
             new[]
             {
-                Part("rect-a", Rect(6, 4), 5),
-                Part("rect-b", Rect(4, 3), 4),
-                Part("rect-c", Rect(2, 7), 3),
+                Part("rect-a", TestDrawingFactory.Rectangle(6, 4), 5),
+                Part("rect-b", TestDrawingFactory.Rectangle(4, 3), 4),
+                Part("rect-c", TestDrawingFactory.Rectangle(2, 7), 3),
             },
             new[] { new NestPlateStock("stock", new Size(30, 50), 4, 1, new Spacing(1, 1, 1, 1)) },
             new NestJobOptions("Strip")
@@ -339,7 +304,11 @@ public class GoldenLayoutTests
 
     private static NestJob ProgressJob() =>
         new(
-            new[] { Part("a", Rect(6, 4), 5), Part("b", Rect(4, 3), 4) },
+            new[]
+            {
+                Part("a", TestDrawingFactory.Rectangle(6, 4), 5),
+                Part("b", TestDrawingFactory.Rectangle(4, 3), 4),
+            },
             new[]
             {
                 new NestPlateStock("small", new Size(14, 14), 4, 1, new Spacing(1, 1, 1, 1)),

OpenNest.Engine.Tests/Jobs/TestDrawingFactory.cs

@@ -14,4 +14,30 @@ internal static class TestDrawingFactory
         program.LineTo(0, 0);
         return program;
     }
+
+    /// <summary>A 6 x 4 L: a 6 x 2 base with a 3 x 2 block on its right half.</summary>
+    public static Program LShape()
+    {
+        var program = new Program();
+        program.MoveTo(0, 0);
+        program.LineTo(6, 0);
+        program.LineTo(6, 4);
+        program.LineTo(3, 4);
+        program.LineTo(3, 2);
+        program.LineTo(0, 2);
+        program.LineTo(0, 0);
+        return program;
+    }
+
+    /// <summary>D-shape: a 3 x 5 block closed on the right by a semicircular arc.</summary>
+    public static Program ArcPart()
+    {
+        var program = new Program();
+        program.MoveTo(0, 0);
+        program.LineTo(3, 0);
+        program.ArcTo(3, 5, 3, 2.5, RotationType.CCW);
+        program.LineTo(0, 5);
+        program.LineTo(0, 0);
+        return program;
+    }
 }