Address PR feedback: remove null check, avoid var, use explicit content checks

Author: Copilot

src/Libraries/Microsoft.Extensions.DataIngestion/README.md

@@ -39,7 +39,7 @@ The vector store must be configured with an embedding generator that accepts `AI
 IEmbeddingGenerator<AIContent, Embedding<float>> aiContentEmbeddingGenerator =
     stringEmbeddingGenerator.AsAIContentEmbeddingGenerator();
 
-using var vectorStore = new InMemoryVectorStore(new()
+using VectorStore vectorStore = new InMemoryVectorStore(new()
 {
     EmbeddingGenerator = aiContentEmbeddingGenerator
 });

src/Libraries/Microsoft.Extensions.DataIngestion/Writers/EmbeddingGeneratorExtensions.cs

@@ -54,7 +54,7 @@ public Task<GeneratedEmbeddings<TEmbedding>> GenerateAsync(
             {
                 if (content is TextContent tc)
                 {
-                    return tc.Text ?? string.Empty;
+                    return tc.Text;
                 }
 
                 throw new NotSupportedException(

test/Libraries/Microsoft.Extensions.DataIngestion.Tests/Chunkers/SemanticSimilarityChunkerTests.cs

@@ -77,7 +77,7 @@ public async Task TwoTopicsParagraphs()
                 }
             });
 
-            using var customGenerator = new Microsoft.Extensions.AI.TestEmbeddingGenerator<AIContent, Embedding<float>>
+            using Microsoft.Extensions.AI.TestEmbeddingGenerator<AIContent, Embedding<float>> customGenerator = new()
             {
                 GenerateAsyncCallback = async (values, options, ct) =>
                 {
@@ -154,7 +154,7 @@ public async Task TwoSeparateTopicsWithAllKindsOfElements()
                 }
             });
 
-            using var customGenerator = new Microsoft.Extensions.AI.TestEmbeddingGenerator<AIContent, Embedding<float>>
+            using Microsoft.Extensions.AI.TestEmbeddingGenerator<AIContent, Embedding<float>> customGenerator = new()
             {
                 GenerateAsyncCallback = async (values, options, ct) =>
                 {

test/Libraries/Microsoft.Extensions.DataIngestion.Tests/Writers/VectorStoreWriterTests.cs

@@ -62,7 +62,7 @@ public async Task CanWriteChunksWithCustomDefinition()
         Assert.NotEqual(Guid.Empty, record.Key);
         Assert.Equal(documentId, record.DocumentId);
         Assert.NotEmpty(record.SerializedContent);
-        Assert.Equal("custom schema content", ((TextContent)record.Content!).Text);
+        Assert.Equal(((TextContent)chunks[0].Content).Text, ((TextContent)record.Content!).Text);
     }
 
     [Fact]
@@ -94,7 +94,7 @@ public async Task CanWriteChunks()
         Assert.NotEqual(Guid.Empty, record.Key);
         Assert.Equal(documentId, record.DocumentId);
         Assert.NotEmpty(record.SerializedContent);
-        Assert.Equal("some content", ((TextContent)record.Content!).Text);
+        Assert.Equal(((TextContent)chunks[0].Content).Text, ((TextContent)record.Content!).Text);
         Assert.True(testEmbeddingGenerator.WasCalled);
     }
 
@@ -125,7 +125,7 @@ public async Task CanWriteChunksWithMetadata()
         Assert.NotNull(record);
         Assert.Equal(documentId, record.DocumentId);
         Assert.NotEmpty(record.SerializedContent);
-        Assert.Equal("some content", ((TextContent)record.Content!).Text);
+        Assert.Equal(((TextContent)chunks[0].Content).Text, ((TextContent)record.Content!).Text);
         Assert.Equal("important", record.Classification);
     }