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-rw-r--r--vendor/modernc.org/token/position.go359
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diff --git a/vendor/modernc.org/token/position.go b/vendor/modernc.org/token/position.go
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index 57895ad6e..000000000
--- a/vendor/modernc.org/token/position.go
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@@ -1,359 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package token is variant of the stdlib package token with types FileSet and
-// Token removed.
-package token // import "modernc.org/token"
-
-import (
- "fmt"
- "sort"
-)
-
-// -----------------------------------------------------------------------------
-// Positions
-
-// Position describes an arbitrary source position
-// including the file, line, and column location.
-// A Position is valid if the line number is > 0.
-type Position struct {
- Filename string // filename, if any
- Offset int // offset, starting at 0
- Line int // line number, starting at 1
- Column int // column number, starting at 1 (byte count)
-}
-
-// IsValid reports whether the position is valid.
-func (pos *Position) IsValid() bool { return pos.Line > 0 }
-
-// String returns a string in one of several forms:
-//
-// file:line:column valid position with file name
-// file:line valid position with file name but no column (column == 0)
-// line:column valid position without file name
-// line valid position without file name and no column (column == 0)
-// file invalid position with file name
-// - invalid position without file name
-func (pos Position) String() string {
- s := pos.Filename
- if pos.IsValid() {
- if s != "" {
- s += ":"
- }
- s += fmt.Sprintf("%d", pos.Line)
- if pos.Column != 0 {
- s += fmt.Sprintf(":%d", pos.Column)
- }
- }
- if s == "" {
- s = "-"
- }
- return s
-}
-
-// Pos is a compact encoding of a source position within a file set.
-// It can be converted into a Position for a more convenient, but much
-// larger, representation.
-//
-// The Pos value for a given file is a number in the range [base, base+size],
-// where base and size are specified when a file is added to the file set.
-// The difference between a Pos value and the corresponding file base
-// corresponds to the byte offset of that position (represented by the Pos value)
-// from the beginning of the file. Thus, the file base offset is the Pos value
-// representing the first byte in the file.
-//
-// To create the Pos value for a specific source offset (measured in bytes),
-// first add the respective file to the current file set using FileSet.AddFile
-// and then call File.Pos(offset) for that file. Given a Pos value p
-// for a specific file set fset, the corresponding Position value is
-// obtained by calling fset.Position(p).
-//
-// Pos values can be compared directly with the usual comparison operators:
-// If two Pos values p and q are in the same file, comparing p and q is
-// equivalent to comparing the respective source file offsets. If p and q
-// are in different files, p < q is true if the file implied by p was added
-// to the respective file set before the file implied by q.
-type Pos int
-
-// The zero value for Pos is NoPos; there is no file and line information
-// associated with it, and NoPos.IsValid() is false. NoPos is always
-// smaller than any other Pos value. The corresponding Position value
-// for NoPos is the zero value for Position.
-const NoPos Pos = 0
-
-// IsValid reports whether the position is valid.
-func (p Pos) IsValid() bool {
- return p != NoPos
-}
-
-// -----------------------------------------------------------------------------
-// File
-
-// A File is a handle for a file belonging to a FileSet.
-// A File has a name, size, and line offset table.
-type File struct {
- name string // file name as provided to AddFile
- base int // Pos value range for this file is [base...base+size]
- size int // file size as provided to AddFile
-
- lines []int // lines contains the offset of the first character for each line (the first entry is always 0)
- infos []lineInfo
-}
-
-// NewFile returns a new file with a given filename and file size.
-//
-func NewFile(filename string, size int) *File {
- return &File{name: filename, base: 1, size: size, lines: []int{0}}
-}
-
-// Name returns the file name of file f as registered with AddFile.
-func (f *File) Name() string {
- return f.name
-}
-
-// Base returns the base offset of file f as registered with AddFile.
-func (f *File) Base() int {
- return f.base
-}
-
-// Size returns the size of file f as registered with AddFile.
-func (f *File) Size() int {
- return f.size
-}
-
-// LineCount returns the number of lines in file f.
-func (f *File) LineCount() int {
- n := len(f.lines)
- return n
-}
-
-// AddLine adds the line offset for a new line.
-// The line offset must be larger than the offset for the previous line
-// and smaller than the file size; otherwise the line offset is ignored.
-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)
- }
-}
-
-// MergeLine merges a line with the following line. It is akin to replacing
-// the newline character at the end of the line with a space (to not change the
-// remaining offsets). To obtain the line number, consult e.g. Position.Line.
-// MergeLine will panic if given an invalid line number.
-func (f *File) MergeLine(line int) {
- if line < 1 {
- panic(fmt.Sprintf("invalid line number %d (should be >= 1)", line))
- }
- if line >= len(f.lines) {
- panic(fmt.Sprintf("invalid line number %d (should be < %d)", line, len(f.lines)))
- }
- // To merge the line numbered <line> with the line numbered <line+1>,
- // we need to remove the entry in lines corresponding to the line
- // numbered <line+1>. The entry in lines corresponding to the line
- // numbered <line+1> is located at index <line>, since indices in lines
- // are 0-based and line numbers are 1-based.
- copy(f.lines[line:], f.lines[line+1:])
- f.lines = f.lines[:len(f.lines)-1]
-}
-
-// SetLines sets the line offsets for a file and reports whether it succeeded.
-// The line offsets are the offsets of the first character of each line;
-// for instance for the content "ab\nc\n" the line offsets are {0, 3}.
-// An empty file has an empty line offset table.
-// Each line offset must be larger than the offset for the previous line
-// and smaller than the file size; otherwise SetLines fails and returns
-// false.
-// Callers must not mutate the provided slice after SetLines returns.
-func (f *File) SetLines(lines []int) bool {
- // verify validity of lines table
- size := f.size
- for i, offset := range lines {
- if i > 0 && offset <= lines[i-1] || size <= offset {
- return false
- }
- }
-
- // set lines table
- f.lines = lines
- return true
-}
-
-// SetLinesForContent sets the line offsets for the given file content.
-// It ignores position-altering //line comments.
-func (f *File) SetLinesForContent(content []byte) {
- var lines []int
- line := 0
- for offset, b := range content {
- if line >= 0 {
- lines = append(lines, line)
- }
- line = -1
- if b == '\n' {
- line = offset + 1
- }
- }
-
- // set lines table
- f.lines = lines
-}
-
-// LineStart returns the Pos value of the start of the specified line.
-// It ignores any alternative positions set using AddLineColumnInfo.
-// LineStart panics if the 1-based line number is invalid.
-func (f *File) LineStart(line int) Pos {
- if line < 1 {
- panic(fmt.Sprintf("invalid line number %d (should be >= 1)", line))
- }
- if line > len(f.lines) {
- panic(fmt.Sprintf("invalid line number %d (should be < %d)", line, len(f.lines)))
- }
- return Pos(f.base + f.lines[line-1])
-}
-
-// A lineInfo object describes alternative file, line, and column
-// number information (such as provided via a //line directive)
-// for a given file offset.
-type lineInfo struct {
- // fields are exported to make them accessible to gob
- Offset int
- Filename string
- Line, Column int
-}
-
-// AddLineInfo is like AddLineColumnInfo with a column = 1 argument.
-// It is here for backward-compatibility for code prior to Go 1.11.
-func (f *File) AddLineInfo(offset int, filename string, line int) {
- f.AddLineColumnInfo(offset, filename, line, 1)
-}
-
-// AddLineColumnInfo adds alternative file, line, and column number
-// information for a given file offset. The offset must be larger
-// than the offset for the previously added alternative line info
-// and smaller than the file size; otherwise the information is
-// ignored.
-//
-// AddLineColumnInfo is typically used to register alternative position
-// information for line directives such as //line filename:line:column.
-func (f *File) AddLineColumnInfo(offset int, filename string, line, column int) {
- if i := len(f.infos); i == 0 || f.infos[i-1].Offset < offset && offset < f.size {
- f.infos = append(f.infos, lineInfo{offset, filename, line, column})
- }
-}
-
-// Pos returns the Pos value for the given file offset;
-// the offset must be <= f.Size().
-// f.Pos(f.Offset(p)) == p.
-func (f *File) Pos(offset int) Pos {
- if offset > f.size {
- panic(fmt.Sprintf("invalid file offset %d (should be <= %d)", offset, f.size))
- }
- return Pos(f.base + offset)
-}
-
-// Offset returns the offset for the given file position p;
-// p must be a valid Pos value in that file.
-// f.Offset(f.Pos(offset)) == offset.
-func (f *File) Offset(p Pos) int {
- if int(p) < f.base || int(p) > f.base+f.size {
- panic(fmt.Sprintf("invalid Pos value %d (should be in [%d, %d])", p, f.base, f.base+f.size))
- }
- return int(p) - f.base
-}
-
-// Line returns the line number for the given file position p;
-// p must be a Pos value in that file or NoPos.
-func (f *File) Line(p Pos) int {
- return f.Position(p).Line
-}
-
-func searchLineInfos(a []lineInfo, x int) int {
- return sort.Search(len(a), func(i int) bool { return a[i].Offset > x }) - 1
-}
-
-// unpack returns the filename and line and column number for a file offset.
-// If adjusted is set, unpack will return the filename and line information
-// possibly adjusted by //line comments; otherwise those comments are ignored.
-func (f *File) unpack(offset int, adjusted bool) (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
- }
- if adjusted && len(f.infos) > 0 {
- // few files have extra line infos
- if i := searchLineInfos(f.infos, offset); i >= 0 {
- alt := &f.infos[i]
- filename = alt.Filename
- if i := searchInts(f.lines, alt.Offset); i >= 0 {
- // i+1 is the line at which the alternative position was recorded
- d := line - (i + 1) // line distance from alternative position base
- line = alt.Line + d
- if alt.Column == 0 {
- // alternative column is unknown => relative column is unknown
- // (the current specification for line directives requires
- // this to apply until the next PosBase/line directive,
- // not just until the new newline)
- column = 0
- } else if d == 0 {
- // the alternative position base is on the current line
- // => column is relative to alternative column
- column = alt.Column + (offset - alt.Offset)
- }
- }
- }
- }
- return
-}
-
-func (f *File) position(p Pos, adjusted bool) (pos Position) {
- offset := int(p) - f.base
- pos.Offset = offset
- pos.Filename, pos.Line, pos.Column = f.unpack(offset, adjusted)
- return
-}
-
-// PositionFor returns the Position value for the given file position p.
-// If adjusted is set, the position may be adjusted by position-altering
-// //line comments; otherwise those comments are ignored.
-// p must be a Pos value in f or NoPos.
-func (f *File) PositionFor(p Pos, adjusted bool) (pos Position) {
- if p != NoPos {
- if int(p) < f.base || int(p) > f.base+f.size {
- panic(fmt.Sprintf("invalid Pos value %d (should be in [%d, %d])", p, f.base, f.base+f.size))
- }
- pos = f.position(p, adjusted)
- }
- return
-}
-
-// Position returns the Position value for the given file position p.
-// Calling f.Position(p) is equivalent to calling f.PositionFor(p, true).
-func (f *File) Position(p Pos) (pos Position) {
- return f.PositionFor(p, true)
-}
-
-// -----------------------------------------------------------------------------
-// Helper functions
-
-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
- //
- // With better compiler optimizations, this may not be needed in the
- // future, but at the moment this change improves the go/printer
- // benchmark performance by ~30%. This has a direct impact on the
- // speed of gofmt and thus seems worthwhile (2011-04-29).
- // TODO(gri): Remove this when compilers have caught up.
- i, j := 0, len(a)
- for i < j {
- h := int(uint(i+j) >> 1) // avoid overflow when computing h
- // i ≤ h < j
- if a[h] <= x {
- i = h + 1
- } else {
- j = h
- }
- }
- return i - 1
-}