tests: add unit tests for FileService

Author: jurczewski

tests/PrivatePdfConverter.Tests/UnitTests/FileServiceUnitTests.cs

@@ -0,0 +1,114 @@
+using PrivatePdfConverter.Services;
+
+namespace PrivatePdfConverter.Tests.UnitTests;
+
+public sealed class FileServiceUnitTests
+{
+    [Theory]
+    [InlineData(".jpg", true)]
+    [InlineData(".jpeg", true)]
+    [InlineData(".png", true)]
+    [InlineData(".bmp", true)]
+    [InlineData(".gif", true)]
+    [InlineData(".tif", true)]
+    [InlineData(".tiff", true)]
+    [InlineData(".webp", true)]
+    [InlineData(".JPG", true)]
+    [InlineData(".txt", false)]
+    [InlineData(".pdf", false)]
+    [InlineData("", false)]
+    [InlineData(".unknown", false)]
+    [InlineData(null, false)]
+    public void IsImage_ShouldReturnCorrectResult(string? extension, bool expected)
+    {
+        // Act
+        var result = extension.IsImage();
+
+        // Assert
+        result.Should().Be(expected);
+    }
+
+    [Fact]
+    public void PrepareOutputFileName_WithOutputProvided_ShouldReturnOutputWithPdfExtension()
+    {
+        // Arrange
+        const string output = "test";
+        const string sourcePath = "dummy.pdf";
+
+        // Act
+        var result = output.PrepareOutputFileName(sourcePath);
+
+        // Assert
+        result.Should().Be("test.pdf");
+    }
+
+    [Fact]
+    public void PrepareOutputFileName_WithOutputPdf_ShouldReturnAsIs()
+    {
+        // Arrange
+        const string output = "test.pdf";
+        const string sourcePath = "dummy.jpg";
+
+        // Act
+        var result = output.PrepareOutputFileName(sourcePath);
+
+        // Assert
+        result.Should().Be("test.pdf");
+    }
+
+    [Fact]
+    public void PrepareOutputFileName_WithNullOutput_ShouldDeriveFromSourcePath()
+    {
+        // Arrange
+        string? output = null;
+        var sourcePath = Path.Combine("images", "photo.jpg");
+
+        // Act
+        var result = output.PrepareOutputFileName(sourcePath);
+
+        // Assert
+        result.Should().Be("photo.pdf");
+    }
+
+    [Fact]
+    public void PrepareOutputFileName_WithEmptyOutput_ShouldDeriveFromSourcePath()
+    {
+        // Arrange
+        const string output = "";
+        var sourcePath = Path.Combine("path", "to", "file.png");
+
+        // Act
+        var result = output.PrepareOutputFileName(sourcePath);
+
+        // Assert
+        result.Should().Be("file.pdf");
+    }
+
+    [Fact]
+    public void PathCombine_WithPath_ShouldCombine()
+    {
+        // Arrange
+        var path = $"C:{Path.DirectorySeparatorChar}dir";
+        const string fileName = "output.pdf";
+
+        // Act
+        var result = Path.Combine(path, fileName);
+
+        // Assert
+        result.Should().Be($"C:{Path.DirectorySeparatorChar}dir{Path.DirectorySeparatorChar}output.pdf");
+    }
+
+    [Fact]
+    public void PathCombine_WithNullPath_ShouldReturnFileName()
+    {
+        // Arrange
+        string? path = null;
+        const string fileName = "output.pdf";
+
+        // Act
+        var result = Path.Combine(path ?? string.Empty, fileName);
+
+        // Assert
+        result.Should().Be("output.pdf");
+    }
+}