Files
ragmcp/tools/parse_go_ast.go
T

333 lines
8.1 KiB
Go

// Build from project root:
// go build -o tools/parse_go_ast tools/parse_go_ast.go
package main
import (
"encoding/json"
"fmt"
"go/ast"
"go/parser"
"go/token"
"os"
"strings"
)
type GoDecl struct {
Name string `json:"name"`
Type string `json:"type"` // "func", "method", "struct", "interface", "type", "var", "const"
Receiver string `json:"receiver,omitempty"` // e.g., "*User"
FullName string `json:"full_name,omitempty"`
Fields []string `json:"fields,omitempty"` // for structs
Methods []string `json:"methods,omitempty"` // for interfaces
Parameters []string `json:"parameters,omitempty"` // for functions/methods
ReturnType string `json:"return_type,omitempty"`
DocComment string `json:"doc_comment,omitempty"`
IsExported bool `json:"is_exported,omitempty"` // starts with capital letter
StartLine int `json:"start_line"`
EndLine int `json:"end_line"`
}
func astTypeToString(expr ast.Expr) string {
if expr == nil {
return ""
}
switch t := expr.(type) {
case *ast.Ident:
return t.Name
case *ast.StarExpr:
return "*" + astTypeToString(t.X)
case *ast.SelectorExpr:
return astTypeToString(t.X) + "." + t.Sel.Name
case *ast.ArrayType:
return "[]" + astTypeToString(t.Elt)
case *ast.MapType:
return "map[" + astTypeToString(t.Key) + "]" + astTypeToString(t.Value)
case *ast.InterfaceType:
return "interface{}"
case *ast.StructType:
return "struct{}"
case *ast.FuncType:
return "func"
case *ast.ChanType:
return "chan " + astTypeToString(t.Value)
case *ast.Ellipsis:
return "..." + astTypeToString(t.Elt)
default:
return "unknown"
}
}
func extractDocComment(comments []*ast.CommentGroup, pos token.Pos, fset *token.FileSet) string {
if len(comments) == 0 {
return ""
}
line := fset.Position(pos).Line
// Look for comments immediately before the declaration
for i := len(comments) - 1; i >= 0; i-- {
cg := comments[i]
cgEndLine := fset.Position(cg.End()).Line
cgStartLine := fset.Position(cg.Pos()).Line
// Comment should be within 1 line of the declaration
if cgEndLine < line && line-cgEndLine <= 1 {
text := strings.TrimSpace(cg.Text())
// Clean up comment markers
text = strings.ReplaceAll(text, "/*", "")
text = strings.ReplaceAll(text, "*/", "")
return strings.TrimSpace(text)
}
// If we've gone too far back, stop looking
if cgStartLine < line-10 {
break
}
}
return ""
}
func extractParameters(fields *ast.FieldList) []string {
if fields == nil {
return nil
}
var params []string
for _, field := range fields.List {
typeStr := astTypeToString(field.Type)
if len(field.Names) == 0 {
// Unnamed parameter
params = append(params, typeStr)
} else {
for _, name := range field.Names {
params = append(params, name.Name+": "+typeStr)
}
}
}
return params
}
func extractReturnType(results *ast.FieldList) string {
if results == nil || len(results.List) == 0 {
return ""
}
if len(results.List) == 1 {
return astTypeToString(results.List[0].Type)
}
// Multiple return values
var types []string
for _, field := range results.List {
types = append(types, astTypeToString(field.Type))
}
return "(" + strings.Join(types, ", ") + ")"
}
func isExported(name string) bool {
if len(name) == 0 {
return false
}
firstRune := []rune(name)[0]
return firstRune >= 'A' && firstRune <= 'Z'
}
func main() {
if len(os.Args) < 2 {
fmt.Fprintln(os.Stderr, "Usage: parse_go_ast <file.go>")
os.Exit(1)
}
filename := os.Args[1]
src, err := os.ReadFile(filename)
if err != nil {
fmt.Fprintf(os.Stderr, "ERR: Failed to read file: %v\n", err)
os.Exit(2)
}
fset := token.NewFileSet()
fileNode, err := parser.ParseFile(fset, filename, src, parser.ParseComments)
if err != nil {
fmt.Fprintf(os.Stderr, "ERR: Failed to parse Go file: %v\n", err)
os.Exit(3)
}
var decls []GoDecl
// Process declarations
for _, d := range fileNode.Decls {
switch d := d.(type) {
case *ast.FuncDecl:
name := d.Name.Name
recvType := ""
if d.Recv != nil && len(d.Recv.List) > 0 {
recvType = astTypeToString(d.Recv.List[0].Type)
}
typ := "function"
fullName := name
if recvType != "" {
typ = "method"
fullName = fmt.Sprintf("(%s).%s", recvType, name)
}
doc := extractDocComment(fileNode.Comments, d.Pos(), fset)
params := extractParameters(d.Type.Params)
returnType := extractReturnType(d.Type.Results)
decl := GoDecl{
Name: name,
Type: typ,
Receiver: recvType,
FullName: fullName,
Parameters: params,
ReturnType: returnType,
DocComment: doc,
IsExported: isExported(name),
StartLine: fset.Position(d.Pos()).Line,
EndLine: fset.Position(d.End()).Line,
}
decls = append(decls, decl)
case *ast.GenDecl:
for _, spec := range d.Specs {
switch s := spec.(type) {
case *ast.TypeSpec:
typName := s.Name.Name
declType := "type"
var fields []string
var methods []string
switch t := s.Type.(type) {
case *ast.StructType:
declType = "struct"
if t.Fields != nil {
for _, f := range t.Fields.List {
fieldType := astTypeToString(f.Type)
if len(f.Names) == 0 {
// Embedded field
fields = append(fields, "embedded:"+fieldType)
} else {
// Named fields
for _, n := range f.Names {
field := n.Name + ": " + fieldType
if f.Tag != nil {
field += " " + f.Tag.Value
}
fields = append(fields, field)
}
}
}
}
case *ast.InterfaceType:
declType = "interface"
if t.Methods != nil {
for _, m := range t.Methods.List {
if len(m.Names) > 0 {
// Named method
for _, name := range m.Names {
methods = append(methods, name.Name)
}
} else {
// Embedded interface
embeddedType := astTypeToString(m.Type)
methods = append(methods, "embedded:"+embeddedType)
}
}
}
}
doc := extractDocComment(fileNode.Comments, s.Pos(), fset)
decl := GoDecl{
Name: typName,
Type: declType,
Fields: fields,
Methods: methods,
DocComment: doc,
IsExported: isExported(typName),
StartLine: fset.Position(d.Pos()).Line,
EndLine: fset.Position(d.End()).Line,
}
decls = append(decls, decl)
case *ast.ValueSpec:
// Variable or constant declarations
varType := "var"
if d.Tok == token.CONST {
varType = "const"
}
for _, name := range s.Names {
doc := extractDocComment(fileNode.Comments, name.Pos(), fset)
// Get the type if specified
typeStr := ""
if s.Type != nil {
typeStr = astTypeToString(s.Type)
}
// Use the individual identifier's position
startLine := fset.Position(name.Pos()).Line
endLine := fset.Position(name.End()).Line
decl := GoDecl{
Name: name.Name,
Type: varType,
ReturnType: typeStr, // Reuse return_type field for variable type
DocComment: doc,
IsExported: isExported(name.Name),
StartLine: startLine,
EndLine: endLine,
}
decls = append(decls, decl)
}
case *ast.ImportSpec:
// Track imports for graph building
importPath := ""
if s.Path != nil {
importPath = strings.Trim(s.Path.Value, "\"")
}
importName := ""
if s.Name != nil {
importName = s.Name.Name
} else {
// Extract package name from path
parts := strings.Split(importPath, "/")
if len(parts) > 0 {
importName = parts[len(parts)-1]
}
}
if importPath != "" {
decl := GoDecl{
Name: importName,
Type: "import",
FullName: importPath,
StartLine: fset.Position(s.Pos()).Line,
EndLine: fset.Position(s.End()).Line,
}
decls = append(decls, decl)
}
}
}
}
}
// Marshal to JSON and output
out, err := json.Marshal(decls)
if err != nil {
fmt.Fprintf(os.Stderr, "ERR: Failed to marshal JSON: %v\n", err)
os.Exit(4)
}
fmt.Println(string(out))
}