Daily Test Coverage Improver: Add comprehensive branch coverage tests

tests/Furnace.Tests/Furnace.Tests.fsproj

@@ -36,6 +36,7 @@
     <Compile Include="TestTorchExtensions.fs" />
 
     <Compile Include="TestReferenceBackend.fs" />
+    <Compile Include="TestBranchCoverage.fs" />
     <Compile Include="TestPlotHelpers.fs" />
     <Compile Include="TestPyplot.fs" />
     <Compile Include="TestData.fs" />

tests/Furnace.Tests/TestBranchCoverage.fs

@@ -0,0 +1,275 @@
+// Copyright (c) 2016-     University of Oxford (Atılım Güneş Baydin <gunes@robots.ox.ac.uk>)
+// and other contributors, see LICENSE in root of repository.
+//
+// BSD 2-Clause License. See LICENSE in root of repository.
+
+namespace Tests
+
+open System
+open NUnit.Framework
+open Furnace
+
+[<TestFixture>]
+type TestBranchCoverage() =
+
+    [<Test>]
+    member _.TestTensorCastingBranches() =
+        let combo = ComboInfo(Backend.Reference, Device.CPU, Dtype.Float32)
+        let t = combo.tensor([1.0f; 2.0f; 3.0f])
+
+        // Test cast to same type (should return same tensor)
+        let sameCast = t.cast(Dtype.Float32)
+        Assert.AreSame(t, sameCast)
+
+        // Test different type casts
+        let intCast = t.cast(Dtype.Int32)
+        Assert.AreEqual(Dtype.Int32, intCast.dtype)
+
+        let doubleCast = t.cast(Dtype.Float64)
+        Assert.AreEqual(Dtype.Float64, doubleCast.dtype)
+
+    [<Test>]
+    member _.TestTensorBackendMoveBranches() =
+        let combo = ComboInfo(Backend.Reference, Device.CPU, Dtype.Float32)
+        let t = combo.tensor([1.0f; 2.0f; 3.0f])
+
+        // Test move to same backend (should return same tensor)
+        let sameBackend = t.move(Backend.Reference)
+        Assert.AreSame(t, sameBackend)
+
+    [<Test>]
+    member _.TestTensorDeviceMoveBranches() =
+        let combo = ComboInfo(Backend.Reference, Device.CPU, Dtype.Float32)
+        let t = combo.tensor([1.0f; 2.0f; 3.0f])
+
+        // Test move to same device (should return same tensor)  
+        let sameDevice = t.move(Device.CPU)
+        Assert.AreSame(t, sameDevice)
+
+    [<Test>]
+    member _.TestGenericCastingBranches() =
+        let combo = ComboInfo(Backend.Reference, Device.CPU, Dtype.Float32)
+        let t = combo.tensor([1.0f; 2.0f; 3.0f])
+
+        // Test different generic cast types
+        let float32Cast = t.cast<float32>()
+        Assert.AreEqual(Dtype.Float32, float32Cast.dtype)
+
+        let float64Cast = t.cast<double>()
+        Assert.AreEqual(Dtype.Float64, float64Cast.dtype)
+
+        let int32Cast = t.cast<int32>()
+        Assert.AreEqual(Dtype.Int32, int32Cast.dtype)
+
+        let int64Cast = t.cast<int64>()
+        Assert.AreEqual(Dtype.Int64, int64Cast.dtype)
+
+        let int16Cast = t.cast<int16>()
+        Assert.AreEqual(Dtype.Int16, int16Cast.dtype)
+
+        let int8Cast = t.cast<int8>()
+        Assert.AreEqual(Dtype.Int8, int8Cast.dtype)
+
+        let bytecast = t.cast<byte>()
+        Assert.AreEqual(Dtype.Byte, bytecast.dtype)
+
+        let boolCast = t.cast<bool>()
+        Assert.AreEqual(Dtype.Bool, boolCast.dtype)
+
+    [<Test>]
+    member _.TestInvalidGenericCastBranch() =
+        let combo = ComboInfo(Backend.Reference, Device.CPU, Dtype.Float32)
+        let t = combo.tensor([1.0f; 2.0f; 3.0f])
+
+        // Test invalid cast type should throw
+        Assert.Throws<System.Exception>(fun () -> 
+            t.cast<string>() |> ignore) |> ignore
+
+    [<Test>]
+    member _.TestTensorComparisons() =
+        let combo = ComboInfo(Backend.Reference, Device.CPU, Dtype.Float32)
+        let t1 = combo.tensor([1.0f; 2.0f; 3.0f])
+        let t2 = combo.tensor([1.0f; 2.0f; 3.0f])
+        let t3 = combo.tensor([1.0f; 2.0f; 4.0f])
+
+        // Test equality branches
+        Assert.True(t1.Equals(t2))
+        Assert.False(t1.Equals(t3))
+        Assert.False(t1.Equals(null))
+
+    [<Test>]
+    member _.TestTensorShapeValidation() =
+        let combo = ComboInfo(Backend.Reference, Device.CPU, Dtype.Float32)
+
+        // Test zero-sized tensors
+        let empty = FurnaceImage.zeros([0], dtype=combo.dtype, backend=combo.backend, device=combo.device)
+        Assert.AreEqual(0, empty.nelement)
+
+        // Test single element tensors
+        let single = combo.tensor([42.0f])
+        Assert.AreEqual(1, single.nelement)
+
+    [<Test>]
+    member _.TestTensorIndexingBoundaries() =
+        let combo = ComboInfo(Backend.Reference, Device.CPU, Dtype.Float32)
+        let t = combo.tensor([1.0f; 2.0f; 3.0f; 4.0f; 5.0f])
+
+        // Test valid indexing
+        Assert.DoesNotThrow(fun () -> t[0] |> ignore)
+        Assert.DoesNotThrow(fun () -> t[4] |> ignore)
+
+        // Test boundary conditions for slicing
+        let slice1 = t[0..2]
+        Assert.AreEqual([|3|], slice1.shape)
+
+        let slice2 = t[1..4]
+        Assert.AreEqual([|4|], slice2.shape)
+
+    [<Test>]
+    member _.TestTensorOperationEdgeCases() =
+        let combo = ComboInfo(Backend.Reference, Device.CPU, Dtype.Float32)
+
+        // Test operations with different sized tensors 
+        let t1x1 = combo.tensor([[1.0f]])
+        let t2x2 = combo.tensor([[1.0f; 2.0f]; [3.0f; 4.0f]])
+
+        // Test broadcasting operations
+        let broadcast1 = t1x1 + t2x2
+        Assert.AreEqual([|2; 2|], broadcast1.shape)
+
+        let broadcast2 = t2x2 * combo.tensor([2.0f])
+        Assert.AreEqual([|2; 2|], broadcast2.shape)
+
+    [<Test>]
+    member _.TestBoolTensorOperations() =
+        let combo = ComboInfo(Backend.Reference, Device.CPU, Dtype.Bool)
+
+        // Test boolean tensor creation and operations
+        let b1 = combo.tensor([true; false; true])
+        let b2 = combo.tensor([false; true; true])
+
+        // Test boolean operations that may have specific branches
+        Assert.AreEqual(Dtype.Bool, b1.dtype)
+        Assert.AreEqual(3, b1.nelement)
+
+        // Test boolean comparisons
+        let eq = b1.eq(b2)
+        Assert.AreEqual(Dtype.Bool, eq.dtype)
+
+    [<Test>]
+    member _.TestTensorCreationEdgeCases() =
+        let combo = ComboInfo(Backend.Reference, Device.CPU, Dtype.Float32)
+
+        // Test creating tensors from different input types
+        let fromInt = combo.tensor([1; 2; 3])
+        Assert.AreEqual(Dtype.Float32, fromInt.dtype) // Should be cast to combo dtype
+
+        let fromFloat = combo.tensor([1.0; 2.0; 3.0])
+        Assert.AreEqual(Dtype.Float32, fromFloat.dtype)
+
+        // Test nested arrays
+        let nested = combo.tensor([[[1.0f]]])
+        Assert.AreEqual([|1; 1; 1|], nested.shape)
+        Assert.AreEqual(3, nested.dim)
+
+    [<Test>]
+    member _.TestTensorMemoryLayout() =
+        let combo = ComboInfo(Backend.Reference, Device.CPU, Dtype.Float32)
+
+        // Test different memory layouts and shapes
+        let t1d = combo.tensor([1.0f; 2.0f; 3.0f; 4.0f])
+        let t2d = t1d.view([2; 2])
+
+        Assert.AreEqual([|4|], t1d.shape)
+        Assert.AreEqual([|2; 2|], t2d.shape)
+        Assert.AreEqual(t1d.nelement, t2d.nelement)
+
+        // Test transpose operations
+        let transposed = t2d.transpose()
+        Assert.AreEqual([|2; 2|], transposed.shape)
+
+    [<Test>]
+    member _.TestTensorReductionEdgeCases() =
+        let combo = ComboInfo(Backend.Reference, Device.CPU, Dtype.Float32)
+
+        // Test reductions on different tensor shapes
+        let t1d = combo.tensor([1.0f; 2.0f; 3.0f; 4.0f])
+        let sum1d = t1d.sum()
+        Assert.True(abs(sum1d.toScalar().toSingle() - 10.0f) < 0.001f)
+
+        let t2d = combo.tensor([[1.0f; 2.0f]; [3.0f; 4.0f]])
+        let sum2d = t2d.sum()
+        Assert.True(abs(sum2d.toScalar().toSingle() - 10.0f) < 0.001f)
+
+        // Test specific dimension reductions
+        let sumDim0 = t2d.sum(0)
+        Assert.AreEqual([|2|], sumDim0.shape)
+
+        let sumDim1 = t2d.sum(1)
+        Assert.AreEqual([|2|], sumDim1.shape)
+
+    [<Test>]
+    member _.TestLowPrecisionTypeOperations() =
+        // Test BFloat16 specific operations for branch coverage
+        let comboBF16 = ComboInfo(Backend.Reference, Device.CPU, Dtype.BFloat16)
+        let t1 = comboBF16.tensor([1.0f; 2.0f; 3.0f])
+        let t2 = comboBF16.tensor([2.0f; 3.0f; 4.0f])
+
+        // Test various comparison operations
+        let eq = t1.eq(t2)
+        let ne = t1.ne(t2)
+        let lt = t1.lt(t2)
+        let le = t1.le(t2)
+        let gt = t1.gt(t2)
+        let ge = t1.ge(t2)
+
+        Assert.AreEqual(Dtype.Bool, eq.dtype)
+        Assert.AreEqual(Dtype.Bool, ne.dtype)
+        Assert.AreEqual(Dtype.Bool, lt.dtype)
+        Assert.AreEqual(Dtype.Bool, le.dtype)
+        Assert.AreEqual(Dtype.Bool, gt.dtype)
+        Assert.AreEqual(Dtype.Bool, ge.dtype)
+
+    [<Test>]
+    member _.TestActivationFunctionBranches() =
+        let combo = ComboInfo(Backend.Reference, Device.CPU, Dtype.Float32)
+        let t = combo.tensor([-2.0f; -1.0f; 0.0f; 1.0f; 2.0f])
+
+        // Test various activation functions that might have different code paths
+        let sigmoid = t.sigmoid()
+        Assert.AreEqual(5, sigmoid.nelement)
+        Assert.AreEqual(Dtype.Float32, sigmoid.dtype)
+
+        let tanh = t.tanh()
+        Assert.AreEqual(5, tanh.nelement)
+
+        let relu = t.relu()
+        Assert.AreEqual(5, relu.nelement)
+
+        let softplus = t.softplus()
+        Assert.AreEqual(5, softplus.nelement)
+
+    [<Test>]
+    member _.TestMathematicalFunctionEdgeCases() =
+        let combo = ComboInfo(Backend.Reference, Device.CPU, Dtype.Float32)
+
+        // Test with various special values that might trigger different branches
+        let positive = combo.tensor([1.0f; 2.0f; 3.0f])
+        let negative = combo.tensor([-1.0f; -2.0f; -3.0f])
+        let mixed = combo.tensor([-1.0f; 0.0f; 1.0f])
+
+        // Test exp on different value ranges
+        let expPos = positive.exp()
+        let expMixed = mixed.exp()
+        Assert.AreEqual(3, expPos.nelement)
+        Assert.AreEqual(3, expMixed.nelement)
+
+        // Test log on positive values (negative would be invalid)
+        let logPos = positive.log()
+        Assert.AreEqual(3, logPos.nelement)
+
+        // Test absolute value 
+        let absNeg = negative.abs()
+        let absMixed = mixed.abs()
+        Assert.AreEqual(3, absNeg.nelement)
+        Assert.AreEqual(3, absMixed.nelement)