summaryrefslogtreecommitdiffstats
path: root/vendor/github.com/d5/tengo/compiler/source/file.go
diff options
context:
space:
mode:
Diffstat (limited to 'vendor/github.com/d5/tengo/compiler/source/file.go')
-rw-r--r--vendor/github.com/d5/tengo/compiler/source/file.go110
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
+}