diff options
Diffstat (limited to 'vendor/github.com/d5/tengo/compiler/source/file.go')
-rw-r--r-- | vendor/github.com/d5/tengo/compiler/source/file.go | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/vendor/github.com/d5/tengo/compiler/source/file.go b/vendor/github.com/d5/tengo/compiler/source/file.go new file mode 100644 index 00000000..9e51c9a4 --- /dev/null +++ b/vendor/github.com/d5/tengo/compiler/source/file.go @@ -0,0 +1,110 @@ +package source + +// File represents a source file. +type File struct { + // File set for the file + set *FileSet + // File name as provided to AddFile + Name string + // Pos value range for this file is [base...base+size] + Base int + // File size as provided to AddFile + Size int + // Lines contains the offset of the first character for each line (the first entry is always 0) + Lines []int +} + +// Set returns FileSet. +func (f *File) Set() *FileSet { + return f.set +} + +// LineCount returns the current number of lines. +func (f *File) LineCount() int { + return len(f.Lines) +} + +// AddLine adds a new line. +func (f *File) AddLine(offset int) { + if i := len(f.Lines); (i == 0 || f.Lines[i-1] < offset) && offset < f.Size { + f.Lines = append(f.Lines, offset) + } +} + +// LineStart returns the position of the first character in the line. +func (f *File) LineStart(line int) Pos { + if line < 1 { + panic("illegal line number (line numbering starts at 1)") + } + + if line > len(f.Lines) { + panic("illegal line number") + } + + return Pos(f.Base + f.Lines[line-1]) +} + +// FileSetPos returns the position in the file set. +func (f *File) FileSetPos(offset int) Pos { + if offset > f.Size { + panic("illegal file offset") + } + + return Pos(f.Base + offset) +} + +// Offset translates the file set position into the file offset. +func (f *File) Offset(p Pos) int { + if int(p) < f.Base || int(p) > f.Base+f.Size { + panic("illegal Pos value") + } + + return int(p) - f.Base +} + +// Position translates the file set position into the file position. +func (f *File) Position(p Pos) (pos FilePos) { + if p != NoPos { + if int(p) < f.Base || int(p) > f.Base+f.Size { + panic("illegal Pos value") + } + + pos = f.position(p) + } + + return +} + +func (f *File) position(p Pos) (pos FilePos) { + offset := int(p) - f.Base + pos.Offset = offset + pos.Filename, pos.Line, pos.Column = f.unpack(offset) + + return +} + +func (f *File) unpack(offset int) (filename string, line, column int) { + filename = f.Name + if i := searchInts(f.Lines, offset); i >= 0 { + line, column = i+1, offset-f.Lines[i]+1 + } + + return +} + +func searchInts(a []int, x int) int { + // This function body is a manually inlined version of: + // return sort.Search(len(a), func(i int) bool { return a[i] > x }) - 1 + i, j := 0, len(a) + for i < j { + h := i + (j-i)/2 // avoid overflow when computing h + // i ≤ h < j + if a[h] <= x { + i = h + 1 + } else { + j = h + } + } + + return i - 1 +} |