More tests (#40)

- **Renamed and enhanced DocumentParserExtensions test:**
- Test class renamed to `DocumentParserExtensionsKtTest` to adhere to
Kotlin naming conventions.
- Added a test case to validate the `parseAsync` method when no source
metadata is available, ensuring proper document parsing.

- **Added unit tests for ChatLanguageModel extensions:**
- Implemented tests for `chatAsync` and `generateAsync` methods in
`ChatLanguageModel`.
- Updated README with a Codecov badge for enhanced code coverage
visibility.
    - Ensures asynchronous chat processing functions correctly.

---------

Co-authored-by: Konstantin Pavlov <{ID}+{username}@users.noreply.github.com>

README.md

@@ -4,6 +4,7 @@
 [![Kotlin CI with Maven](https://github.com/kpavlov/langchain4j-kotlin/actions/workflows/maven.yml/badge.svg?branch=main)](https://github.com/kpavlov/langchain4j-kotlin/actions/workflows/maven.yml)
 [![Codacy Badge](https://app.codacy.com/project/badge/Grade/644f664ad05a4a009b299bc24c8be4b8)](https://app.codacy.com/gh/kpavlov/langchain4j-kotlin/dashboard?utm_source=gh&utm_medium=referral&utm_content=&utm_campaign=Badge_grade)
 [![Codacy Coverage](https://app.codacy.com/project/badge/Coverage/644f664ad05a4a009b299bc24c8be4b8)](https://app.codacy.com/gh/kpavlov/langchain4j-kotlin/dashboard?utm_source=gh&utm_medium=referral&utm_content=&utm_campaign=Badge_coverage)
+[![codecov](https://codecov.io/gh/kpavlov/langchain4j-kotlin/graph/badge.svg?token=VYIJ92CYHD)](https://codecov.io/gh/kpavlov/langchain4j-kotlin)
 [![Maintainability](https://api.codeclimate.com/v1/badges/176ba2c4e657d3e7981a/maintainability)](https://codeclimate.com/github/kpavlov/langchain4j-kotlin/maintainability)
 [![Api Docs](https://img.shields.io/badge/api-docs-blue)](https://kpavlov.github.io/langchain4j-kotlin/api/)
 Kotlin enhancements for [LangChain4j](https://github.com/langchain4j/langchain4j), providing coroutine support and Flow-based streaming capabilities for chat language models.

langchain4j-kotlin/src/test/kotlin/me/kpavlov/langchain4j/kotlin/data/document/DocumentParserExtensionsTest.kt → langchain4j-kotlin/src/test/kotlin/me/kpavlov/langchain4j/kotlin/data/document/DocumentParserExtensionsKtTest.kt

@@ -3,6 +3,7 @@ package me.kpavlov.langchain4j.kotlin.data.document
 import assertk.assertThat
 import assertk.assertions.containsOnly
 import assertk.assertions.isEqualTo
+import assertk.assertions.isSameInstanceAs
 import dev.langchain4j.data.document.Document
 import dev.langchain4j.data.document.Document.ABSOLUTE_DIRECTORY_PATH
 import dev.langchain4j.data.document.Document.FILE_NAME
@@ -18,7 +19,7 @@ import org.mockito.junit.jupiter.MockitoExtension
 import org.mockito.kotlin.whenever
 
 @ExtendWith(MockitoExtension::class)
-internal class DocumentParserExtensionsTest {
+internal class DocumentParserExtensionsKtTest {
     @Mock
     private lateinit var documentParser: DocumentParser
 
@@ -55,4 +56,23 @@ internal class DocumentParserExtensionsTest {
                 )
         }
     }
+
+    @Test
+    fun `parseAsync should return parser document when no source metadata is present`() {
+        val documentContent = "parsed document content"
+        runTest {
+            val inputStream = documentContent.byteInputStream()
+            val documentMetadata = Metadata.from(mapOf<String, Any?>("title" to "Bar"))
+            val fileMetadata = Metadata.from(mapOf<String, Any?>())
+            val document = Document.from(documentContent, documentMetadata)
+
+            whenever(documentSource.inputStream()).thenReturn(inputStream)
+            whenever(documentParser.parse(inputStream)).thenReturn(document)
+            whenever(documentSource.metadata()).thenReturn(fileMetadata)
+
+            val result = documentParser.parseAsync(documentSource, Dispatchers.IO)
+
+            assertThat(result).isSameInstanceAs(document)
+        }
+    }
 }

langchain4j-kotlin/src/test/kotlin/me/kpavlov/langchain4j/kotlin/model/chat/ChatLanguageModelExtensionsKtTest.kt

@@ -0,0 +1,88 @@
+package me.kpavlov.langchain4j.kotlin.model.chat
+
+import assertk.assertThat
+import assertk.assertions.isEqualTo
+import assertk.assertions.isSameInstanceAs
+import dev.langchain4j.data.message.AiMessage
+import dev.langchain4j.data.message.ChatMessage
+import dev.langchain4j.model.chat.ChatLanguageModel
+import dev.langchain4j.model.chat.request.ChatRequest
+import dev.langchain4j.model.chat.response.ChatResponse
+import dev.langchain4j.model.output.Response
+import kotlinx.coroutines.test.runTest
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.extension.ExtendWith
+import org.mockito.Mock
+import org.mockito.junit.jupiter.MockitoExtension
+import org.mockito.kotlin.mock
+import org.mockito.kotlin.verify
+import org.mockito.kotlin.whenever
+
+@ExtendWith(MockitoExtension::class)
+internal class ChatLanguageModelExtensionsKtTest {
+    @Mock
+    private lateinit var mockModel: ChatLanguageModel
+
+    @Mock
+    private lateinit var request: ChatRequest
+
+    @Mock
+    private lateinit var requestBuilder: ChatRequest.Builder
+
+    @Mock
+    private lateinit var expectedResponse: ChatResponse
+
+    /**
+     * This class tests the `chatAsync` extension function of `ChatLanguageModel`.
+     * The function takes a `ChatRequest` or a `ChatRequest.Builder` as input,
+     * performs asynchronous processing, and returns a `ChatResponse`.
+     */
+
+    @Test
+    fun `chatAsync should return expected ChatResponse when using ChatRequest`() =
+        runTest {
+            whenever(mockModel.chat(request)).thenReturn(expectedResponse)
+
+            val actualResponse = mockModel.chatAsync(request)
+
+            assertThat(actualResponse).isEqualTo(expectedResponse)
+            verify(mockModel).chat(request)
+        }
+
+    @Test
+    fun `generateAsync should return expected AiMessage when using valid ChatMessages`() =
+        runTest {
+            val messages = mock<List<ChatMessage>>()
+            val expectedAiMessage = mock<Response<AiMessage>>()
+
+            whenever(mockModel.generate(messages)).thenReturn(expectedAiMessage)
+
+            val actualAiMessage = mockModel.generateAsync(messages)
+
+            assertThat(actualAiMessage).isSameInstanceAs(expectedAiMessage)
+        }
+
+    @Test
+    fun `chatAsync should return expected ChatResponse when using ChatRequest Builder`() =
+        runTest {
+            whenever(requestBuilder.build()).thenReturn(request)
+            whenever(mockModel.chat(request)).thenReturn(expectedResponse)
+
+            val actualResponse = mockModel.chatAsync(requestBuilder)
+
+            assertThat(actualResponse).isEqualTo(expectedResponse)
+            verify(mockModel).chat(request)
+        }
+
+    @Test
+    fun `chat should return expected ChatResponse when using ChatRequest Builder`() =
+        runTest {
+            whenever(requestBuilder.build()).thenReturn(request)
+            whenever(mockModel.chat(request)).thenReturn(expectedResponse)
+
+            val actualResponse = mockModel.chat(requestBuilder)
+
+            assertThat(actualResponse).isEqualTo(expectedResponse)
+            verify(mockModel).chat(request)
+        }
+}