delve/vendor/github.com/cpuguy83/go-md2man/v2/md2man/roff.go
Hyang-Ah Hana Kim f74b7a6e39
all: update github.com/spf13/cobra to v1.1.3 (#2572)
This removes indirect dependencies from go.mod, and
includes the fix for the missing -help flag info.

The latest cobra release is v1.2.1. Given that there were
minor security-related dependency cleanup during v1.2 release,
I was tempted to pick up the latest version, but that caused
dependency updates in golang.org/x/sys and golang.org/x/tools
which may be too recent (golang.org/x/* follow the go's release
support policy, so recent versions may not be compatible with
go versions beyond go's official version support policy).

Verified that dlv still builds with go1.12.x.
(go1.12 is the oldest version of go that can build the latest delve already).

$ go get -d github.com/spf13/cobra@v1.1.3
$ go mod tidy
$ go mod vendor
$ go run _scripts/gen-usage-docs.go
2021-07-22 11:05:37 -07:00

346 lines
8.4 KiB
Go

package md2man
import (
"fmt"
"io"
"os"
"strings"
"github.com/russross/blackfriday/v2"
)
// roffRenderer implements the blackfriday.Renderer interface for creating
// roff format (manpages) from markdown text
type roffRenderer struct {
extensions blackfriday.Extensions
listCounters []int
firstHeader bool
defineTerm bool
listDepth int
}
const (
titleHeader = ".TH "
topLevelHeader = "\n\n.SH "
secondLevelHdr = "\n.SH "
otherHeader = "\n.SS "
crTag = "\n"
emphTag = "\\fI"
emphCloseTag = "\\fP"
strongTag = "\\fB"
strongCloseTag = "\\fP"
breakTag = "\n.br\n"
paraTag = "\n.PP\n"
hruleTag = "\n.ti 0\n\\l'\\n(.lu'\n"
linkTag = "\n\\[la]"
linkCloseTag = "\\[ra]"
codespanTag = "\\fB\\fC"
codespanCloseTag = "\\fR"
codeTag = "\n.PP\n.RS\n\n.nf\n"
codeCloseTag = "\n.fi\n.RE\n"
quoteTag = "\n.PP\n.RS\n"
quoteCloseTag = "\n.RE\n"
listTag = "\n.RS\n"
listCloseTag = "\n.RE\n"
arglistTag = "\n.TP\n"
tableStart = "\n.TS\nallbox;\n"
tableEnd = ".TE\n"
tableCellStart = "T{\n"
tableCellEnd = "\nT}\n"
)
// NewRoffRenderer creates a new blackfriday Renderer for generating roff documents
// from markdown
func NewRoffRenderer() *roffRenderer { // nolint: golint
var extensions blackfriday.Extensions
extensions |= blackfriday.NoIntraEmphasis
extensions |= blackfriday.Tables
extensions |= blackfriday.FencedCode
extensions |= blackfriday.SpaceHeadings
extensions |= blackfriday.Footnotes
extensions |= blackfriday.Titleblock
extensions |= blackfriday.DefinitionLists
return &roffRenderer{
extensions: extensions,
}
}
// GetExtensions returns the list of extensions used by this renderer implementation
func (r *roffRenderer) GetExtensions() blackfriday.Extensions {
return r.extensions
}
// RenderHeader handles outputting the header at document start
func (r *roffRenderer) RenderHeader(w io.Writer, ast *blackfriday.Node) {
// disable hyphenation
out(w, ".nh\n")
}
// RenderFooter handles outputting the footer at the document end; the roff
// renderer has no footer information
func (r *roffRenderer) RenderFooter(w io.Writer, ast *blackfriday.Node) {
}
// RenderNode is called for each node in a markdown document; based on the node
// type the equivalent roff output is sent to the writer
func (r *roffRenderer) RenderNode(w io.Writer, node *blackfriday.Node, entering bool) blackfriday.WalkStatus {
var walkAction = blackfriday.GoToNext
switch node.Type {
case blackfriday.Text:
r.handleText(w, node, entering)
case blackfriday.Softbreak:
out(w, crTag)
case blackfriday.Hardbreak:
out(w, breakTag)
case blackfriday.Emph:
if entering {
out(w, emphTag)
} else {
out(w, emphCloseTag)
}
case blackfriday.Strong:
if entering {
out(w, strongTag)
} else {
out(w, strongCloseTag)
}
case blackfriday.Link:
if !entering {
out(w, linkTag+string(node.LinkData.Destination)+linkCloseTag)
}
case blackfriday.Image:
// ignore images
walkAction = blackfriday.SkipChildren
case blackfriday.Code:
out(w, codespanTag)
escapeSpecialChars(w, node.Literal)
out(w, codespanCloseTag)
case blackfriday.Document:
break
case blackfriday.Paragraph:
// roff .PP markers break lists
if r.listDepth > 0 {
return blackfriday.GoToNext
}
if entering {
out(w, paraTag)
} else {
out(w, crTag)
}
case blackfriday.BlockQuote:
if entering {
out(w, quoteTag)
} else {
out(w, quoteCloseTag)
}
case blackfriday.Heading:
r.handleHeading(w, node, entering)
case blackfriday.HorizontalRule:
out(w, hruleTag)
case blackfriday.List:
r.handleList(w, node, entering)
case blackfriday.Item:
r.handleItem(w, node, entering)
case blackfriday.CodeBlock:
out(w, codeTag)
escapeSpecialChars(w, node.Literal)
out(w, codeCloseTag)
case blackfriday.Table:
r.handleTable(w, node, entering)
case blackfriday.TableCell:
r.handleTableCell(w, node, entering)
case blackfriday.TableHead:
case blackfriday.TableBody:
case blackfriday.TableRow:
// no action as cell entries do all the nroff formatting
return blackfriday.GoToNext
default:
fmt.Fprintln(os.Stderr, "WARNING: go-md2man does not handle node type "+node.Type.String())
}
return walkAction
}
func (r *roffRenderer) handleText(w io.Writer, node *blackfriday.Node, entering bool) {
var (
start, end string
)
// handle special roff table cell text encapsulation
if node.Parent.Type == blackfriday.TableCell {
if len(node.Literal) > 30 {
start = tableCellStart
end = tableCellEnd
} else {
// end rows that aren't terminated by "tableCellEnd" with a cr if end of row
if node.Parent.Next == nil && !node.Parent.IsHeader {
end = crTag
}
}
}
out(w, start)
escapeSpecialChars(w, node.Literal)
out(w, end)
}
func (r *roffRenderer) handleHeading(w io.Writer, node *blackfriday.Node, entering bool) {
if entering {
switch node.Level {
case 1:
if !r.firstHeader {
out(w, titleHeader)
r.firstHeader = true
break
}
out(w, topLevelHeader)
case 2:
out(w, secondLevelHdr)
default:
out(w, otherHeader)
}
}
}
func (r *roffRenderer) handleList(w io.Writer, node *blackfriday.Node, entering bool) {
openTag := listTag
closeTag := listCloseTag
if node.ListFlags&blackfriday.ListTypeDefinition != 0 {
// tags for definition lists handled within Item node
openTag = ""
closeTag = ""
}
if entering {
r.listDepth++
if node.ListFlags&blackfriday.ListTypeOrdered != 0 {
r.listCounters = append(r.listCounters, 1)
}
out(w, openTag)
} else {
if node.ListFlags&blackfriday.ListTypeOrdered != 0 {
r.listCounters = r.listCounters[:len(r.listCounters)-1]
}
out(w, closeTag)
r.listDepth--
}
}
func (r *roffRenderer) handleItem(w io.Writer, node *blackfriday.Node, entering bool) {
if entering {
if node.ListFlags&blackfriday.ListTypeOrdered != 0 {
out(w, fmt.Sprintf(".IP \"%3d.\" 5\n", r.listCounters[len(r.listCounters)-1]))
r.listCounters[len(r.listCounters)-1]++
} else if node.ListFlags&blackfriday.ListTypeDefinition != 0 {
// state machine for handling terms and following definitions
// since blackfriday does not distinguish them properly, nor
// does it seperate them into separate lists as it should
if !r.defineTerm {
out(w, arglistTag)
r.defineTerm = true
} else {
r.defineTerm = false
}
} else {
out(w, ".IP \\(bu 2\n")
}
} else {
out(w, "\n")
}
}
func (r *roffRenderer) handleTable(w io.Writer, node *blackfriday.Node, entering bool) {
if entering {
out(w, tableStart)
//call walker to count cells (and rows?) so format section can be produced
columns := countColumns(node)
out(w, strings.Repeat("l ", columns)+"\n")
out(w, strings.Repeat("l ", columns)+".\n")
} else {
out(w, tableEnd)
}
}
func (r *roffRenderer) handleTableCell(w io.Writer, node *blackfriday.Node, entering bool) {
var (
start, end string
)
if node.IsHeader {
start = codespanTag
end = codespanCloseTag
}
if entering {
if node.Prev != nil && node.Prev.Type == blackfriday.TableCell {
out(w, "\t"+start)
} else {
out(w, start)
}
} else {
// need to carriage return if we are at the end of the header row
if node.IsHeader && node.Next == nil {
end = end + crTag
}
out(w, end)
}
}
// because roff format requires knowing the column count before outputting any table
// data we need to walk a table tree and count the columns
func countColumns(node *blackfriday.Node) int {
var columns int
node.Walk(func(node *blackfriday.Node, entering bool) blackfriday.WalkStatus {
switch node.Type {
case blackfriday.TableRow:
if !entering {
return blackfriday.Terminate
}
case blackfriday.TableCell:
if entering {
columns++
}
default:
}
return blackfriday.GoToNext
})
return columns
}
func out(w io.Writer, output string) {
io.WriteString(w, output) // nolint: errcheck
}
func needsBackslash(c byte) bool {
for _, r := range []byte("-_&\\~") {
if c == r {
return true
}
}
return false
}
func escapeSpecialChars(w io.Writer, text []byte) {
for i := 0; i < len(text); i++ {
// escape initial apostrophe or period
if len(text) >= 1 && (text[0] == '\'' || text[0] == '.') {
out(w, "\\&")
}
// directly copy normal characters
org := i
for i < len(text) && !needsBackslash(text[i]) {
i++
}
if i > org {
w.Write(text[org:i]) // nolint: errcheck
}
// escape a character
if i >= len(text) {
break
}
w.Write([]byte{'\\', text[i]}) // nolint: errcheck
}
}