Add a BodySpan property to the CppFunction class.

src/CppAst.Tests/TestFunctions.cs

@@ -1,4 +1,6 @@
 using NUnit.Framework;
+using System;
+using System.IO;
 
 namespace CppAst.Tests
 {
@@ -353,6 +355,154 @@ public void TestFunctionPointersByParam()
             );
         }
 
+        [Test]
+        public void TestFunctionBody()
+        {
+            var options = new CppParserOptions();
+            options.ParseFunctionBodies = true;
+            var headerFilename = "test_function_body.h";
+
+            var text = @"
+void function0();
+int function1(int a, float b) {
+    return a + (int)b;
+}
+float function2(int x);
+";
+
+            var currentDirectory = Environment.CurrentDirectory;
+            var headerFile = Path.Combine(currentDirectory, headerFilename);
+            File.WriteAllText(headerFile, text);
+
+            var compilation = CppParser.ParseFile(headerFile, options);
+
+            Assert.False(compilation.HasErrors);
+            Assert.AreEqual(3, compilation.Functions.Count);
+
+            {
+                var cppFunction = compilation.Functions[0];
+                Assert.AreEqual("function0", cppFunction.Name);
+                Assert.IsNull(cppFunction.BodySpan);
+            }
+
+            {
+                var cppFunction = compilation.Functions[1];
+                Assert.AreEqual("function1", cppFunction.Name);
+                Assert.IsNotNull(cppFunction.BodySpan);
+                Assert.Greater(cppFunction.BodySpan.Value.Start.Line, 0);
+                Assert.Greater(cppFunction.BodySpan.Value.End.Line, 0);
+                Assert.GreaterOrEqual(cppFunction.BodySpan.Value.End.Offset, cppFunction.BodySpan.Value.Start.Offset);
+            }
+
+            {
+                var cppFunction = compilation.Functions[2];
+                Assert.AreEqual("function2", cppFunction.Name);
+                Assert.IsNull(cppFunction.BodySpan);
+            }
+        }
+
+        [Test]
+        public void TestInlineMethodBody()
+        {
+            var options = new CppParserOptions();
+            options.ParseFunctionBodies = true;
+            var headerFilename = "test_inline_method_body.h";
+
+            var text = @"
+typedef unsigned int ImWchar;
+
+class ImFont {
+public:
+    bool IsGlyphInFont(ImWchar c)
+    {
+        return false;
+    }
+
+    bool AnotherMethod(ImWchar c) {
+        if (c == 0) return true;
+        return false;
+    }
+};
+";
+
+            var currentDirectory = Environment.CurrentDirectory;
+            var headerFile = Path.Combine(currentDirectory, headerFilename);
+            File.WriteAllText(headerFile, text);
+
+            var compilation = CppParser.ParseFile(headerFile, options);
+
+            Assert.False(compilation.HasErrors);
+            Assert.AreEqual(1, compilation.Classes.Count);
+
+            var cls = compilation.Classes[0];
+            Assert.AreEqual("ImFont", cls.Name);
+            Assert.AreEqual(2, cls.Functions.Count);
+
+            {
+                var cppFunction = cls.Functions[0];
+                Assert.AreEqual("IsGlyphInFont", cppFunction.Name);
+                Assert.IsNotNull(cppFunction.BodySpan, "IsGlyphInFont should have BodySpan - this is the bug reported");
+                Assert.Greater(cppFunction.BodySpan.Value.Start.Line, 0);
+                Assert.Greater(cppFunction.BodySpan.Value.End.Line, 0);
+                Assert.GreaterOrEqual(cppFunction.BodySpan.Value.End.Offset, cppFunction.BodySpan.Value.Start.Offset);
+            }
+
+            {
+                var cppFunction = cls.Functions[1];
+                Assert.AreEqual("AnotherMethod", cppFunction.Name);
+                Assert.IsNotNull(cppFunction.BodySpan, "AnotherMethod should have BodySpan");
+                Assert.Greater(cppFunction.BodySpan.Value.Start.Line, 0);
+                Assert.Greater(cppFunction.BodySpan.Value.End.Line, 0);
+                Assert.GreaterOrEqual(cppFunction.BodySpan.Value.End.Offset, cppFunction.BodySpan.Value.Start.Offset);
+            }
+        }
+
+        [Test]
+        public void TestMethodDefinitionOutsideClass()
+        {
+            var options = new CppParserOptions();
+            options.ParseFunctionBodies = true;
+            var headerFilename = "test_method_outside_class.h";
+
+            var text = @"
+typedef unsigned int ImWchar;
+
+class ImFont {
+public:
+    bool IsGlyphInFont(ImWchar c);
+};
+
+bool ImFont::IsGlyphInFont(ImWchar c)
+{
+    return false;
+}
+";
+
+            var currentDirectory = Environment.CurrentDirectory;
+            var headerFile = Path.Combine(currentDirectory, headerFilename);
+            File.WriteAllText(headerFile, text);
+
+            var compilation = CppParser.ParseFile(headerFile, options);
+
+            Assert.False(compilation.HasErrors);
+            Assert.AreEqual(1, compilation.Classes.Count);
+
+            var cls = compilation.Classes[0];
+            Assert.AreEqual("ImFont", cls.Name);
+
+
+            Assert.AreEqual(1, cls.Functions.Count);
+
+            {
+                var cppFunction = cls.Functions[0];
+                Assert.AreEqual("IsGlyphInFont", cppFunction.Name);
+                Assert.IsNotNull(cppFunction.BodySpan, "IsGlyphInFont should have BodySpan - this is the bug reported (method defined outside class)");
+                Assert.Greater(cppFunction.BodySpan.Value.Start.Line, 0);
+                Assert.Greater(cppFunction.BodySpan.Value.End.Line, 0);
+                Assert.GreaterOrEqual(cppFunction.BodySpan.Value.End.Offset, cppFunction.BodySpan.Value.Start.Offset);
+            }
+        }
+
 
 
     }

src/CppAst/CppFunction.cs

@@ -93,6 +93,11 @@ public int DefaultParamCount
             }
         }
 
+        /// <summary>
+        /// Gets or sets the source span of the function body implementation.
+        /// </summary>
+        public CppSourceSpan? BodySpan { get; set; }
+
         /// <summary>
         /// Gets or sets the flags of this function.
         /// </summary>

src/CppAst/CppModelBuilder.cs

@@ -1549,11 +1549,69 @@ private CppFunction VisitFunctionDecl(CXCursor cursor, CXCursor parent, void* da
 
             //We need ignore the function define out in the class definition here(Otherwise it will has two same functions here~)!
             var semKind = cursor.SemanticParent.Kind;
-            if ((semKind == CXCursorKind.CXCursor_StructDecl || 
+            bool isMethodDefinedOutsideClass = (semKind == CXCursorKind.CXCursor_StructDecl || 
                 semKind == CXCursorKind.CXCursor_ClassDecl ||
                 semKind == CXCursorKind.CXCursor_ClassTemplate)
-                && cursor.LexicalParent != cursor.SemanticParent)
+                && cursor.LexicalParent != cursor.SemanticParent;
+
+            if (isMethodDefinedOutsideClass)
             {
+                // Find the previously created function in the class and update its BodySpan
+                if (cppClass != null)
+                {
+                    CppFunction existingFunction = null;
+
+                    // Search in Functions, Constructors, and Destructors
+                    foreach (var func in cppClass.Functions)
+                    {
+                        if (func.Name == functionName)
+                        {
+                            existingFunction = func;
+                            break;
+                        }
+                    }
+
+                    if (existingFunction == null)
+                    {
+                        foreach (var ctor in cppClass.Constructors)
+                        {
+                            if (ctor.Name == functionName)
+                            {
+                                existingFunction = ctor;
+                                break;
+                            }
+                        }
+                    }
+
+                    if (existingFunction == null)
+                    {
+                        foreach (var dtor in cppClass.Destructors)
+                        {
+                            if (dtor.Name == functionName)
+                            {
+                                existingFunction = dtor;
+                                break;
+                            }
+                        }
+                    }
+
+                    // If we found the existing function, update its BodySpan
+                    if (existingFunction != null && cursor.IsDefinition)
+                    {
+                        cursor.VisitChildren((childCursor, functionCursor, clientData) =>
+                        {
+                            if (childCursor.Kind == CXCursorKind.CXCursor_CompoundStmt)
+                            {
+                                var bodyStart = GetSourceLocation(childCursor.Extent.Start);
+                                var bodyEnd = GetSourceLocation(childCursor.Extent.End);
+                                existingFunction.BodySpan = new CppSourceSpan(bodyStart, bodyEnd);
+                                return CXChildVisitResult.CXChildVisit_Break;
+                            }
+                            return CXChildVisitResult.CXChildVisit_Continue;
+                        }, new CXClientData((IntPtr)data));
+                    }
+                }
+
                 return null;
             }
 
@@ -1649,6 +1707,21 @@ private CppFunction VisitFunctionDecl(CXCursor cursor, CXCursor parent, void* da
             ParseAttributes(cursor, cppFunction, true);
             cppFunction.CallingConvention = GetCallingConvention(cursor.Type);
 
+            if (cursor.IsDefinition)
+            {
+                cursor.VisitChildren((childCursor, functionCursor, clientData) =>
+                {
+                    if (childCursor.Kind == CXCursorKind.CXCursor_CompoundStmt)
+                    {
+                        var bodyStart = GetSourceLocation(childCursor.Extent.Start);
+                        var bodyEnd = GetSourceLocation(childCursor.Extent.End);
+                        cppFunction.BodySpan = new CppSourceSpan(bodyStart, bodyEnd);
+                        return CXChildVisitResult.CXChildVisit_Break;
+                    }
+                    return CXChildVisitResult.CXChildVisit_Continue;
+                }, new CXClientData((IntPtr)data));
+            }
+
             int i = 0;
             cursor.VisitChildren((argCursor, functionCursor, clientData) =>
             {

src/CppAst/CppParser.cs

@@ -122,7 +122,10 @@ private static unsafe CppCompilation ParseInternal(List<CppFileOrString> cppFile
             }
 
             var translationFlags = CXTranslationUnit_Flags.CXTranslationUnit_None;
-            translationFlags |= CXTranslationUnit_Flags.CXTranslationUnit_SkipFunctionBodies;                   // Don't traverse function bodies
+            if (!options.ParseFunctionBodies)
+            {
+                translationFlags |= CXTranslationUnit_Flags.CXTranslationUnit_SkipFunctionBodies;                   // Don't traverse function bodies
+            }
             translationFlags |= CXTranslationUnit_Flags.CXTranslationUnit_IncludeAttributedTypes;               // Include attributed types in CXType
             translationFlags |= CXTranslationUnit_Flags.CXTranslationUnit_VisitImplicitAttributes;              // Implicit attributes should be visited
 

src/CppAst/CppParserOptions.cs

@@ -37,6 +37,7 @@ public CppParserOptions()
             ParseSystemIncludes = true;
             ParseTokenAttributes = false;
             ParseCommentAttribute = false;
+            ParseFunctionBodies = false;
 
             // Default triple targets
             TargetCpu = IntPtr.Size == 8 ? CppTargetCpu.X86_64 : CppTargetCpu.X86;
@@ -101,6 +102,11 @@ public CppParserOptions()
         /// </summary>
         public bool ParseCommentAttribute { get; set; }
 
+        /// <summary>
+        /// Gets or sets a boolean indicating whether to parse function bodies. Default is <c>false</c>
+        /// </summary>
+        public bool ParseFunctionBodies { get; set; }
+
         /// <summary>
         /// Sets <see cref="ParseMacros"/> to <c>true</c> and return this instance.
         /// </summary>