+++ /dev/null
-// Copyright 2019 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 span contains support for representing with positions and ranges in
-// text files.
-package span
-
-import (
- "encoding/json"
- "fmt"
- "path"
-)
-
-// Span represents a source code range in standardized form.
-type Span struct {
- v span
-}
-
-// Point represents a single point within a file.
-// In general this should only be used as part of a Span, as on its own it
-// does not carry enough information.
-type Point struct {
- v point
-}
-
-type span struct {
- URI URI `json:"uri"`
- Start point `json:"start"`
- End point `json:"end"`
-}
-
-type point struct {
- Line int `json:"line"`
- Column int `json:"column"`
- Offset int `json:"offset"`
-}
-
-// Invalid is a span that reports false from IsValid
-var Invalid = Span{v: span{Start: invalidPoint.v, End: invalidPoint.v}}
-
-var invalidPoint = Point{v: point{Line: 0, Column: 0, Offset: -1}}
-
-// Converter is the interface to an object that can convert between line:column
-// and offset forms for a single file.
-type Converter interface {
- //ToPosition converts from an offset to a line:column pair.
- ToPosition(offset int) (int, int, error)
- //ToOffset converts from a line:column pair to an offset.
- ToOffset(line, col int) (int, error)
-}
-
-func New(uri URI, start Point, end Point) Span {
- s := Span{v: span{URI: uri, Start: start.v, End: end.v}}
- s.v.clean()
- return s
-}
-
-func NewPoint(line, col, offset int) Point {
- p := Point{v: point{Line: line, Column: col, Offset: offset}}
- p.v.clean()
- return p
-}
-
-func Compare(a, b Span) int {
- if r := CompareURI(a.URI(), b.URI()); r != 0 {
- return r
- }
- if r := comparePoint(a.v.Start, b.v.Start); r != 0 {
- return r
- }
- return comparePoint(a.v.End, b.v.End)
-}
-
-func ComparePoint(a, b Point) int {
- return comparePoint(a.v, b.v)
-}
-
-func comparePoint(a, b point) int {
- if !a.hasPosition() {
- if a.Offset < b.Offset {
- return -1
- }
- if a.Offset > b.Offset {
- return 1
- }
- return 0
- }
- if a.Line < b.Line {
- return -1
- }
- if a.Line > b.Line {
- return 1
- }
- if a.Column < b.Column {
- return -1
- }
- if a.Column > b.Column {
- return 1
- }
- return 0
-}
-
-func (s Span) HasPosition() bool { return s.v.Start.hasPosition() }
-func (s Span) HasOffset() bool { return s.v.Start.hasOffset() }
-func (s Span) IsValid() bool { return s.v.Start.isValid() }
-func (s Span) IsPoint() bool { return s.v.Start == s.v.End }
-func (s Span) URI() URI { return s.v.URI }
-func (s Span) Start() Point { return Point{s.v.Start} }
-func (s Span) End() Point { return Point{s.v.End} }
-func (s *Span) MarshalJSON() ([]byte, error) { return json.Marshal(&s.v) }
-func (s *Span) UnmarshalJSON(b []byte) error { return json.Unmarshal(b, &s.v) }
-
-func (p Point) HasPosition() bool { return p.v.hasPosition() }
-func (p Point) HasOffset() bool { return p.v.hasOffset() }
-func (p Point) IsValid() bool { return p.v.isValid() }
-func (p *Point) MarshalJSON() ([]byte, error) { return json.Marshal(&p.v) }
-func (p *Point) UnmarshalJSON(b []byte) error { return json.Unmarshal(b, &p.v) }
-func (p Point) Line() int {
- if !p.v.hasPosition() {
- panic(fmt.Errorf("position not set in %v", p.v))
- }
- return p.v.Line
-}
-func (p Point) Column() int {
- if !p.v.hasPosition() {
- panic(fmt.Errorf("position not set in %v", p.v))
- }
- return p.v.Column
-}
-func (p Point) Offset() int {
- if !p.v.hasOffset() {
- panic(fmt.Errorf("offset not set in %v", p.v))
- }
- return p.v.Offset
-}
-
-func (p point) hasPosition() bool { return p.Line > 0 }
-func (p point) hasOffset() bool { return p.Offset >= 0 }
-func (p point) isValid() bool { return p.hasPosition() || p.hasOffset() }
-func (p point) isZero() bool {
- return (p.Line == 1 && p.Column == 1) || (!p.hasPosition() && p.Offset == 0)
-}
-
-func (s *span) clean() {
- //this presumes the points are already clean
- if !s.End.isValid() || (s.End == point{}) {
- s.End = s.Start
- }
-}
-
-func (p *point) clean() {
- if p.Line < 0 {
- p.Line = 0
- }
- if p.Column <= 0 {
- if p.Line > 0 {
- p.Column = 1
- } else {
- p.Column = 0
- }
- }
- if p.Offset == 0 && (p.Line > 1 || p.Column > 1) {
- p.Offset = -1
- }
-}
-
-// Format implements fmt.Formatter to print the Location in a standard form.
-// The format produced is one that can be read back in using Parse.
-func (s Span) Format(f fmt.State, c rune) {
- fullForm := f.Flag('+')
- preferOffset := f.Flag('#')
- // we should always have a uri, simplify if it is file format
- //TODO: make sure the end of the uri is unambiguous
- uri := string(s.v.URI)
- if c == 'f' {
- uri = path.Base(uri)
- } else if !fullForm {
- uri = s.v.URI.Filename()
- }
- fmt.Fprint(f, uri)
- if !s.IsValid() || (!fullForm && s.v.Start.isZero() && s.v.End.isZero()) {
- return
- }
- // see which bits of start to write
- printOffset := s.HasOffset() && (fullForm || preferOffset || !s.HasPosition())
- printLine := s.HasPosition() && (fullForm || !printOffset)
- printColumn := printLine && (fullForm || (s.v.Start.Column > 1 || s.v.End.Column > 1))
- fmt.Fprint(f, ":")
- if printLine {
- fmt.Fprintf(f, "%d", s.v.Start.Line)
- }
- if printColumn {
- fmt.Fprintf(f, ":%d", s.v.Start.Column)
- }
- if printOffset {
- fmt.Fprintf(f, "#%d", s.v.Start.Offset)
- }
- // start is written, do we need end?
- if s.IsPoint() {
- return
- }
- // we don't print the line if it did not change
- printLine = fullForm || (printLine && s.v.End.Line > s.v.Start.Line)
- fmt.Fprint(f, "-")
- if printLine {
- fmt.Fprintf(f, "%d", s.v.End.Line)
- }
- if printColumn {
- if printLine {
- fmt.Fprint(f, ":")
- }
- fmt.Fprintf(f, "%d", s.v.End.Column)
- }
- if printOffset {
- fmt.Fprintf(f, "#%d", s.v.End.Offset)
- }
-}
-
-func (s Span) WithPosition(c Converter) (Span, error) {
- if err := s.update(c, true, false); err != nil {
- return Span{}, err
- }
- return s, nil
-}
-
-func (s Span) WithOffset(c Converter) (Span, error) {
- if err := s.update(c, false, true); err != nil {
- return Span{}, err
- }
- return s, nil
-}
-
-func (s Span) WithAll(c Converter) (Span, error) {
- if err := s.update(c, true, true); err != nil {
- return Span{}, err
- }
- return s, nil
-}
-
-func (s *Span) update(c Converter, withPos, withOffset bool) error {
- if !s.IsValid() {
- return fmt.Errorf("cannot add information to an invalid span")
- }
- if withPos && !s.HasPosition() {
- if err := s.v.Start.updatePosition(c); err != nil {
- return err
- }
- if s.v.End.Offset == s.v.Start.Offset {
- s.v.End = s.v.Start
- } else if err := s.v.End.updatePosition(c); err != nil {
- return err
- }
- }
- if withOffset && (!s.HasOffset() || (s.v.End.hasPosition() && !s.v.End.hasOffset())) {
- if err := s.v.Start.updateOffset(c); err != nil {
- return err
- }
- if s.v.End.Line == s.v.Start.Line && s.v.End.Column == s.v.Start.Column {
- s.v.End.Offset = s.v.Start.Offset
- } else if err := s.v.End.updateOffset(c); err != nil {
- return err
- }
- }
- return nil
-}
-
-func (p *point) updatePosition(c Converter) error {
- line, col, err := c.ToPosition(p.Offset)
- if err != nil {
- return err
- }
- p.Line = line
- p.Column = col
- return nil
-}
-
-func (p *point) updateOffset(c Converter) error {
- offset, err := c.ToOffset(p.Line, p.Column)
- if err != nil {
- return err
- }
- p.Offset = offset
- return nil
-}
projects / dotfiles / .git / blobdiff