Fixed TDS message severity handling (#2741)

* Fixed TDS meesage severity handling

* Fixed test cases which were failed due to onDone method is rasing ErrorSeverity 20

---------

Co-authored-by: Divang Sharma <[email protected]>

Author: divang

src/main/java/com/microsoft/sqlserver/jdbc/SQLServerError.java

@@ -347,6 +347,10 @@ public void setErrorNumber(int newErrorNumber) {
         this.errorNumber = newErrorNumber;
     }
 
+    public void setErrorMessage(String errorMessage) {
+        this.errorMessage = errorMessage;
+    }
+
     @Override
     public SQLException toSqlExceptionOrSqlWarning() {
         return new SQLServerException(this);

src/main/java/com/microsoft/sqlserver/jdbc/SQLServerResource.java

@@ -575,6 +575,8 @@ protected Object[][] getContents() {
         {"R_vectorByteArrayLength", "Vector byte array length must be at least 8 bytes."},
         {"R_invalidVectorData", "The provided type of data is not supported for vector."},
         {"R_vectorByteArrayMultipleOfBytesPerDimension", "Byte array length must be a multiple of {0} for vector of type {1}."},
+        {"R_severeError", "A severe error occurred on the current command.  The results, if any, should be discarded."},
+           
     };
 }
 // @formatter:on

src/main/java/com/microsoft/sqlserver/jdbc/tdsparser.java

@@ -245,12 +245,20 @@ boolean onRetValue(TDSReader tdsReader) throws SQLServerException {
     }
 
     boolean onDone(TDSReader tdsReader) throws SQLServerException {
+        short status = tdsReader.peekStatusFlag();
         StreamDone doneToken = new StreamDone();
         doneToken.setFromTDS(tdsReader);
         if (doneToken.isFinal()) {
             // Response is completely processed hence decrement unprocessed response count.
             tdsReader.getConnection().getSessionRecovery().decrementUnprocessedResponseCount();
         }
+
+        if ((status & TDS.DONE_SRVERROR) != 0) {
+            SQLServerError syntheticError = new SQLServerError();
+            syntheticError.setErrorMessage(SQLServerException.getErrString("R_severeError"));
+            syntheticError.setErrorSeverity((byte) 20);
+            addDatabaseError(syntheticError);
+        }
         return true;
     }
 

src/test/java/com/microsoft/sqlserver/jdbc/TDSTokenHandlerTest.java

@@ -0,0 +1,78 @@
+package com.microsoft.sqlserver.jdbc;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.Mockito.*;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.BeforeEach;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+/**
+ * Unit test for TDSTokenHandler onDone method, specifically testing
+ * severity 25 (fatal) error handling and SQLServerError generation.
+ */
+public class TDSTokenHandlerTest {
+
+    @Mock
+    private TDSReader mockTdsReader;
+    
+    @Mock
+    private SQLServerConnection mockConnection;
+    
+    @Mock
+    private IdleConnectionResiliency mockSessionRecovery;
+    
+    @Mock
+    private TDSCommand mockCommand;
+    
+    @BeforeEach
+    void setUp() throws SQLServerException {
+        MockitoAnnotations.openMocks(this);
+        
+        // Setup basic mocks
+        when(mockTdsReader.getConnection()).thenReturn(mockConnection);
+        when(mockConnection.getSessionRecovery()).thenReturn(mockSessionRecovery);
+        when(mockTdsReader.getCommand()).thenReturn(mockCommand);
+        
+        // Mock the TDS data reading methods that StreamDone.setFromTDS() needs
+        when(mockTdsReader.readUnsignedByte()).thenReturn(TDS.TDS_DONE); // token type
+        when(mockTdsReader.readShort()).thenReturn((short) 0); // status and curCmd
+        when(mockTdsReader.readLong()).thenReturn(0L); // rowCount
+    }
+    
+    /**
+     * Simplified test case specifically for Severity 20 fatal error simulation.
+     * This test mocks the TDS status flags to simulate a severity 20 error
+     * and verifies that SQLServerError is properly generated.
+     */
+    @Test
+    void testSeverity20FatalErrorSimulation() throws SQLServerException {
+        // Arrange - Simulate severity 20 fatal error with DONE_SRVERROR status
+        short severity20ErrorStatus = (short) (TDS.DONE_SRVERROR);
+        
+        // Mock TDSReader to return the error status that would be set for severity 20 errors
+        when(mockTdsReader.peekStatusFlag()).thenReturn(severity20ErrorStatus);
+        
+        // Override the readShort to return the error status for the StreamDone.setFromTDS() call
+        // The first readShort call is for the status field in StreamDone
+        when(mockTdsReader.readShort())
+            .thenReturn(severity20ErrorStatus);
+
+        // Create token handler to test
+        TDSTokenHandler handler = new TDSTokenHandler("Severity20Test");
+        
+        // Act - Call onDone method which should detect the error status and create SQLServerError
+        handler.onDone(mockTdsReader);
+        
+        // Verify that SQLServerError was generated due to the error status
+        SQLServerError generatedError = handler.getDatabaseError();
+        assertNotNull(generatedError, "SQLServerError must be generated for severity 20 error condition");
+
+        // Verify the error message is the expected server error message
+        String expectedErrorMessage = SQLServerException.getErrString("R_severeError");
+        assertEquals(expectedErrorMessage, generatedError.getErrorMessage(), 
+                "Generated error should have R_severeError message for fatal errors");
+       
+    }
+}