// addFile adds a file to the index if possible and returns the file set file
// and the file's AST if it was successfully parsed as a Go file. If addFile
// failed (that is, if the file was not added), it returns file == nil.
func (x *Indexer) addFile(filename string, goFile bool) (file *token.File, ast *ast.File) {
// open file
f, err := fs.Open(filename)
if err != nil {
return
}
defer f.Close()
// The file set's base offset and x.sources size must be in lock-step;
// this permits the direct mapping of suffix array lookup results to
// to corresponding Pos values.
//
// When a file is added to the file set, its offset base increases by
// the size of the file + 1; and the initial base offset is 1. Add an
// extra byte to the sources here.
x.sources.WriteByte(0)
// If the sources length doesn't match the file set base at this point
// the file set implementation changed or we have another error.
base := x.fset.Base()
if x.sources.Len() != base {
panic("internal error: file base incorrect")
}
// append file contents (src) to x.sources
if _, err := x.sources.ReadFrom(f); err == nil {
src := x.sources.Bytes()[base:]
if goFile {
// parse the file and in the process add it to the file set
if ast, err = parser.ParseFile(x.fset, filename, src, parser.ParseComments); err == nil {
file = x.fset.File(ast.Pos()) // ast.Pos() is inside the file
return
}
// file has parse errors, and the AST may be incorrect -
// set lines information explicitly and index as ordinary
// text file (cannot fall through to the text case below
// because the file has already been added to the file set
// by the parser)
file = x.fset.File(token.Pos(base)) // token.Pos(base) is inside the file
file.SetLinesForContent(src)
ast = nil
return
}
if isText(src) {
// only add the file to the file set (for the full text index)
file = x.fset.AddFile(filename, x.fset.Base(), len(src))
file.SetLinesForContent(src)
return
}
}
// discard possibly added data
x.sources.Truncate(base - 1) // -1 to remove added byte 0 since no file was added
return
}
func (s *BranchStmt) End() token.Pos {
if s.Label != nil {
return s.Label.End()
}
return token.Pos(int(s.TokPos) + len(s.Tok.String()))
}
func (c *Comment) End() token.Pos { return token.Pos(int(c.Slash) + len(c.Text)) }
func (x *BasicLit) End() token.Pos { return token.Pos(int(x.ValuePos) + len(x.Value)) }
func (x *Ident) End() token.Pos { return token.Pos(int(x.NamePos) + len(x.Name)) }
// LookupRegexp returns the number of matches and the matches where a regular
// expression r is found in the full text index. At most n matches are
// returned (thus found <= n).
//
func (x *Index) LookupRegexp(r *regexp.Regexp, n int) (found int, result []FileLines) {
if x.suffixes == nil || n <= 0 {
return
}
// n > 0
var list positionList
// FindAllIndex may returns matches that span across file boundaries.
// Such matches are unlikely, buf after eliminating them we may end up
// with fewer than n matches. If we don't have enough at the end, redo
// the search with an increased value n1, but only if FindAllIndex
// returned all the requested matches in the first place (if it
// returned fewer than that there cannot be more).
for n1 := n; found < n; n1 += n - found {
found = 0
matches := x.suffixes.FindAllIndex(r, n1)
// compute files, exclude matches that span file boundaries,
// and map offsets to file-local offsets
list = make(positionList, len(matches))
for _, m := range matches {
// by construction, an offset corresponds to the Pos value
// for the file set - use it to get the file and line
p := token.Pos(m[0])
if file := x.fset.File(p); file != nil {
if base := file.Base(); base <= m[1] && m[1] <= base+file.Size() {
// match [m[0], m[1]) is within the file boundaries
list[found].filename = file.Name()
list[found].line = file.Line(p)
found++
}
}
}
if found == n || len(matches) < n1 {
// found all matches or there's no chance to find more
break
}
}
list = list[0:found]
sort.Sort(list) // sort by filename
// collect matches belonging to the same file
var last string
var lines []int
addLines := func() {
if len(lines) > 0 {
// remove duplicate lines
result = append(result, FileLines{last, unique(lines)})
lines = nil
}
}
for _, m := range list {
if m.filename != last {
addLines()
last = m.filename
}
lines = append(lines, m.line)
}
addLines()
return
}
