Skip to content
Fetching contributors…
Cannot retrieve contributors at this time
385 lines (329 sloc) 8.69 KB
package main
import (
"bytes"
"go/ast"
"go/parser"
"go/token"
)
func parse_decl_list(fset *token.FileSet, data []byte) ([]ast.Decl, error) {
var buf bytes.Buffer
buf.WriteString("package p;")
buf.Write(data)
file, err := parser.ParseFile(fset, "", buf.Bytes(), 0)
if err != nil {
return file.Decls, err
}
return file.Decls, nil
}
//-------------------------------------------------------------------------
// auto_complete_file
//-------------------------------------------------------------------------
type auto_complete_file struct {
name string
package_name string
decls map[string]*decl
packages package_imports
filescope *scope
scope *scope
cursor int // for current file buffer only
fset *token.FileSet
}
func new_auto_complete_file(name string) *auto_complete_file {
p := new(auto_complete_file)
p.name = name
p.cursor = -1
p.fset = token.NewFileSet()
return p
}
func (f *auto_complete_file) offset(p token.Pos) int {
const fixlen = len("package p;")
return f.fset.Position(p).Offset - fixlen
}
// this one is used for current file buffer exclusively
func (f *auto_complete_file) process_data(data []byte) {
cur, filedata, block := rip_off_decl(data, f.cursor)
file, _ := parser.ParseFile(f.fset, "", filedata, 0)
f.package_name = package_name(file)
f.decls = make(map[string]*decl)
f.packages = new_package_imports(f.name, file.Decls)
f.filescope = new_scope(nil)
f.scope = f.filescope
for _, d := range file.Decls {
anonymify_ast(d, 0, f.filescope)
}
// process all top-level declarations
for _, decl := range file.Decls {
append_to_top_decls(f.decls, decl, f.scope)
}
if block != nil {
// process local function as top-level declaration
decls, _ := parse_decl_list(f.fset, block)
for _, d := range decls {
anonymify_ast(d, 0, f.filescope)
}
for _, decl := range decls {
append_to_top_decls(f.decls, decl, f.scope)
}
// process function internals
f.cursor = cur
for _, decl := range decls {
f.process_decl_locals(decl)
}
}
}
func (f *auto_complete_file) process_decl_locals(decl ast.Decl) {
switch t := decl.(type) {
case *ast.FuncDecl:
if f.cursor_in(t.Body) {
s := f.scope
f.scope = new_scope(f.scope)
f.process_field_list(t.Recv, s)
f.process_field_list(t.Type.Params, s)
f.process_field_list(t.Type.Results, s)
f.process_block_stmt(t.Body)
}
}
}
func (f *auto_complete_file) process_decl(decl ast.Decl) {
if t, ok := decl.(*ast.GenDecl); ok && f.offset(t.TokPos) > f.cursor {
return
}
prevscope := f.scope
foreach_decl(decl, func(data *foreach_decl_struct) {
class := ast_decl_class(data.decl)
if class != decl_type {
f.scope, prevscope = advance_scope(f.scope)
}
for i, name := range data.names {
typ, v, vi := data.type_value_index(i)
d := new_decl_full(name.Name, class, 0, typ, v, vi, prevscope)
if d == nil {
return
}
f.scope.add_named_decl(d)
}
})
}
func (f *auto_complete_file) process_block_stmt(block *ast.BlockStmt) {
if block != nil && f.cursor_in(block) {
f.scope, _ = advance_scope(f.scope)
for _, stmt := range block.List {
f.process_stmt(stmt)
}
// hack to process all func literals
v := new(func_lit_visitor)
v.ctx = f
ast.Walk(v, block)
}
}
type func_lit_visitor struct {
ctx *auto_complete_file
}
func (v *func_lit_visitor) Visit(node ast.Node) ast.Visitor {
if t, ok := node.(*ast.FuncLit); ok && v.ctx.cursor_in(t.Body) {
var s *scope
v.ctx.scope, s = advance_scope(v.ctx.scope)
v.ctx.process_field_list(t.Type.Params, s)
v.ctx.process_field_list(t.Type.Results, s)
v.ctx.process_block_stmt(t.Body)
return nil
}
return v
}
func (f *auto_complete_file) process_stmt(stmt ast.Stmt) {
switch t := stmt.(type) {
case *ast.DeclStmt:
f.process_decl(t.Decl)
case *ast.AssignStmt:
f.process_assign_stmt(t)
case *ast.IfStmt:
if f.cursor_in_if_head(t) {
f.process_stmt(t.Init)
} else if f.cursor_in(t.Body) {
f.scope, _ = advance_scope(f.scope)
f.process_stmt(t.Init)
f.process_block_stmt(t.Body)
}
f.process_stmt(t.Else)
case *ast.BlockStmt:
f.process_block_stmt(t)
case *ast.RangeStmt:
f.process_range_stmt(t)
case *ast.ForStmt:
if f.cursor_in_for_head(t) {
f.process_stmt(t.Init)
} else if f.cursor_in(t.Body) {
f.scope, _ = advance_scope(f.scope)
f.process_stmt(t.Init)
f.process_block_stmt(t.Body)
}
case *ast.SwitchStmt:
f.process_switch_stmt(t)
case *ast.TypeSwitchStmt:
f.process_type_switch_stmt(t)
case *ast.SelectStmt:
f.process_select_stmt(t)
case *ast.LabeledStmt:
f.process_stmt(t.Stmt)
}
}
func (f *auto_complete_file) process_select_stmt(a *ast.SelectStmt) {
if !f.cursor_in(a.Body) {
return
}
var prevscope *scope
f.scope, prevscope = advance_scope(f.scope)
var last_cursor_after *ast.CommClause
for _, s := range a.Body.List {
if cc := s.(*ast.CommClause); f.cursor > f.offset(cc.Colon) {
last_cursor_after = cc
}
}
if last_cursor_after != nil {
if last_cursor_after.Comm != nil {
//if lastCursorAfter.Lhs != nil && lastCursorAfter.Tok == token.DEFINE {
if astmt, ok := last_cursor_after.Comm.(*ast.AssignStmt); ok && astmt.Tok == token.DEFINE {
vname := astmt.Lhs[0].(*ast.Ident).Name
v := new_decl_var(vname, nil, astmt.Rhs[0], -1, prevscope)
f.scope.add_named_decl(v)
}
}
for _, s := range last_cursor_after.Body {
f.process_stmt(s)
}
}
}
func (f *auto_complete_file) process_type_switch_stmt(a *ast.TypeSwitchStmt) {
if !f.cursor_in(a.Body) {
return
}
var prevscope *scope
f.scope, prevscope = advance_scope(f.scope)
f.process_stmt(a.Init)
// type var
var tv *decl
if a, ok := a.Assign.(*ast.AssignStmt); ok {
lhs := a.Lhs
rhs := a.Rhs
if lhs != nil && len(lhs) == 1 {
tvname := lhs[0].(*ast.Ident).Name
tv = new_decl_var(tvname, nil, rhs[0], -1, prevscope)
}
}
var last_cursor_after *ast.CaseClause
for _, s := range a.Body.List {
if cc := s.(*ast.CaseClause); f.cursor > f.offset(cc.Colon) {
last_cursor_after = cc
}
}
if last_cursor_after != nil {
if tv != nil {
if last_cursor_after.List != nil && len(last_cursor_after.List) == 1 {
tv.typ = last_cursor_after.List[0]
tv.value = nil
}
f.scope.add_named_decl(tv)
}
for _, s := range last_cursor_after.Body {
f.process_stmt(s)
}
}
}
func (f *auto_complete_file) process_switch_stmt(a *ast.SwitchStmt) {
if !f.cursor_in(a.Body) {
return
}
f.scope, _ = advance_scope(f.scope)
f.process_stmt(a.Init)
var last_cursor_after *ast.CaseClause
for _, s := range a.Body.List {
if cc := s.(*ast.CaseClause); f.cursor > f.offset(cc.Colon) {
last_cursor_after = cc
}
}
if last_cursor_after != nil {
for _, s := range last_cursor_after.Body {
f.process_stmt(s)
}
}
}
func (f *auto_complete_file) process_range_stmt(a *ast.RangeStmt) {
if !f.cursor_in(a.Body) {
return
}
var prevscope *scope
f.scope, prevscope = advance_scope(f.scope)
if a.Tok == token.DEFINE {
if t, ok := a.Key.(*ast.Ident); ok {
d := new_decl_var(t.Name, nil, a.X, 0, prevscope)
if d != nil {
d.flags |= decl_rangevar
f.scope.add_named_decl(d)
}
}
if a.Value != nil {
if t, ok := a.Value.(*ast.Ident); ok {
d := new_decl_var(t.Name, nil, a.X, 1, prevscope)
if d != nil {
d.flags |= decl_rangevar
f.scope.add_named_decl(d)
}
}
}
}
f.process_block_stmt(a.Body)
}
func (f *auto_complete_file) process_assign_stmt(a *ast.AssignStmt) {
if a.Tok != token.DEFINE || f.offset(a.TokPos) > f.cursor {
return
}
names := make([]*ast.Ident, len(a.Lhs))
for i, name := range a.Lhs {
id, ok := name.(*ast.Ident)
if !ok {
// something is wrong, just ignore the whole stmt
return
}
names[i] = id
}
var prevscope *scope
f.scope, prevscope = advance_scope(f.scope)
pack := decl_pack{names, nil, a.Rhs}
for i, name := range pack.names {
typ, v, vi := pack.type_value_index(i)
d := new_decl_var(name.Name, typ, v, vi, prevscope)
if d == nil {
continue
}
f.scope.add_named_decl(d)
}
}
func (f *auto_complete_file) process_field_list(field_list *ast.FieldList, s *scope) {
if field_list != nil {
decls := ast_field_list_to_decls(field_list, decl_var, 0, s)
for _, d := range decls {
f.scope.add_named_decl(d)
}
}
}
func (f *auto_complete_file) cursor_in_if_head(s *ast.IfStmt) bool {
if f.cursor > f.offset(s.If) && f.cursor <= f.offset(s.Body.Lbrace) {
return true
}
return false
}
func (f *auto_complete_file) cursor_in_for_head(s *ast.ForStmt) bool {
if f.cursor > f.offset(s.For) && f.cursor <= f.offset(s.Body.Lbrace) {
return true
}
return false
}
func (f *auto_complete_file) cursor_in(block *ast.BlockStmt) bool {
if f.cursor == -1 || block == nil {
return false
}
if f.cursor > f.offset(block.Lbrace) && f.cursor <= f.offset(block.Rbrace) {
return true
}
return false
}
Something went wrong with that request. Please try again.