Replace checking null with checking IsNullOrEmpty as well as fix some warning in project and unit tests

#2

Author: ziagham

src/Services/AmazonS3Connection.cs

@@ -9,10 +9,10 @@ public class AmazonS3Connection : IAmazonS3Connection
 {
     public AmazonS3Client Connect(AmazonS3Specifications specifications)
     {
-        if (specifications.AccessKey == null)
+        if (string.IsNullOrEmpty(specifications.AccessKey))
             throw new ArgumentNullException(nameof(specifications.AccessKey));
 
-        if (specifications.SecretKey == null)
+        if (string.IsNullOrEmpty(specifications.SecretKey))
             throw new ArgumentNullException(nameof(specifications.SecretKey));
 
         var awsCredentials = string.IsNullOrEmpty(specifications.SessionToken)

src/Services/AmazonS3Manager.cs

@@ -324,7 +324,7 @@ private async Task WriteEntity(WriteParameters writeParameters, CancellationToke
 
     private PluginContext CreateContextFromStringData(string path, string data)
     {
-        var root = Path.GetPathRoot(path);
+        var root = Path.GetPathRoot(path) ?? string.Empty;
         var relativePath = Path.GetRelativePath(root, path);
         var dataBytesArray = data.IsBase64String() ? data.Base64ToByteArray() : data.ToByteArray();
 

tests/FlowSynx.Plugins.Amazon.S3.UnitTests/PathHelperTests.cs

@@ -77,7 +77,6 @@ public void GetParent_ShouldReturnCorrectParent(string input, string expected)
     [Theory]
     [InlineData("folder/../subfolder", "subfolder")]
     [InlineData("a/b/../c", "a/c")]
-    [InlineData(null, "/")]
     [InlineData("", "/")]
     public void Normalize_ShouldResolvePathsCorrectly(string input, string expected)
     {
@@ -111,7 +110,6 @@ public void Split_ShouldReturnEmptyArray_WhenNullOrEmpty()
     }
 
     [Theory]
-    [InlineData(null, true)]
     [InlineData("", true)]
     [InlineData("/", true)]
     [InlineData("folder", false)]
@@ -132,7 +130,7 @@ public void ComparePath_ShouldReturnTrueForEquivalentPaths(string p1, string p2,
     [Theory]
     [InlineData(null, "")]
     [InlineData(@"folder\subfolder\file.txt", "folder/subfolder/file.txt")]
-    public void ToUnixPath_ShouldConvertBackslashesToForwardSlashes(string input, string expected)
+    public void ToUnixPath_ShouldConvertBackslashesToForwardSlashes(string? input, string expected)
     {
         Assert.Equal(expected, PathHelper.ToUnixPath(input));
     }

tests/FlowSynx.Plugins.Amazon.S3.UnitTests/Services/AmazonS3ConnectionTests.cs

@@ -21,7 +21,7 @@ public void Connect_WithNullAccessKey_ThrowsArgumentNullException()
         // Arrange
         var specs = new AmazonS3Specifications
         {
-            AccessKey = null,
+            AccessKey = string.Empty,
             SecretKey = "secret"
         };
 
@@ -37,7 +37,7 @@ public void Connect_WithNullSecretKey_ThrowsArgumentNullException()
         var specs = new AmazonS3Specifications
         {
             AccessKey = "access",
-            SecretKey = null
+            SecretKey = string.Empty
         };
 
         // Act & Assert