Fixed immediate value formatting in Group1 instruction handlers

X86DisassemblerTests/InstructionTests/CallRm32Tests.cs

@@ -0,0 +1,47 @@
+using X86Disassembler.X86;
+
+namespace X86DisassemblerTests.InstructionTests;
+
+/// <summary>
+/// Tests for CALL r/m32 instruction (0xFF /2)
+/// </summary>
+public class CallRm32Tests
+{
+    /// <summary>
+    /// Tests the CALL r32 instruction (0xFF /2) with register operand
+    /// </summary>
+    [Fact]
+    public void TestCallReg()
+    {
+        // Arrange
+        byte[] code = { 0xFF, 0xD3 }; // CALL EBX
+        
+        // Act
+        Disassembler disassembler = new Disassembler(code, 0x1000);
+        var instructions = disassembler.Disassemble();
+        
+        // Assert
+        Assert.Single(instructions);
+        Assert.Equal("call", instructions[0].Mnemonic);
+        Assert.Equal("ebx", instructions[0].Operands);
+    }
+    
+    /// <summary>
+    /// Tests the CALL m32 instruction (0xFF /2) with memory operand
+    /// </summary>
+    [Fact]
+    public void TestCallMem()
+    {
+        // Arrange
+        byte[] code = { 0xFF, 0x10 }; // CALL DWORD PTR [EAX]
+        
+        // Act
+        Disassembler disassembler = new Disassembler(code, 0x1000);
+        var instructions = disassembler.Disassemble();
+        
+        // Assert
+        Assert.Single(instructions);
+        Assert.Equal("call", instructions[0].Mnemonic);
+        Assert.Equal("dword ptr [eax]", instructions[0].Operands);
+    }
+}