--- /dev/null
+// Copyright 2012 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 present
+
+import (
+ "bufio"
+ "bytes"
+ "fmt"
+ "html/template"
+ "path/filepath"
+ "regexp"
+ "strconv"
+ "strings"
+)
+
+// PlayEnabled specifies whether runnable playground snippets should be
+// displayed in the present user interface.
+var PlayEnabled = false
+
+// TODO(adg): replace the PlayEnabled flag with something less spaghetti-like.
+// Instead this will probably be determined by a template execution Context
+// value that contains various global metadata required when rendering
+// templates.
+
+// NotesEnabled specifies whether presenter notes should be displayed in the
+// present user interface.
+var NotesEnabled = false
+
+func init() {
+ Register("code", parseCode)
+ Register("play", parseCode)
+}
+
+type Code struct {
+ Cmd string // original command from present source
+ Text template.HTML
+ Play bool // runnable code
+ Edit bool // editable code
+ FileName string // file name
+ Ext string // file extension
+ Raw []byte // content of the file
+}
+
+func (c Code) PresentCmd() string { return c.Cmd }
+func (c Code) TemplateName() string { return "code" }
+
+// The input line is a .code or .play entry with a file name and an optional HLfoo marker on the end.
+// Anything between the file and HL (if any) is an address expression, which we treat as a string here.
+// We pick off the HL first, for easy parsing.
+var (
+ highlightRE = regexp.MustCompile(`\s+HL([a-zA-Z0-9_]+)?$`)
+ hlCommentRE = regexp.MustCompile(`(.+) // HL(.*)$`)
+ codeRE = regexp.MustCompile(`\.(code|play)\s+((?:(?:-edit|-numbers)\s+)*)([^\s]+)(?:\s+(.*))?$`)
+)
+
+// parseCode parses a code present directive. Its syntax:
+// .code [-numbers] [-edit] <filename> [address] [highlight]
+// The directive may also be ".play" if the snippet is executable.
+func parseCode(ctx *Context, sourceFile string, sourceLine int, cmd string) (Elem, error) {
+ cmd = strings.TrimSpace(cmd)
+ origCmd := cmd
+
+ // Pull off the HL, if any, from the end of the input line.
+ highlight := ""
+ if hl := highlightRE.FindStringSubmatchIndex(cmd); len(hl) == 4 {
+ if hl[2] < 0 || hl[3] < 0 {
+ return nil, fmt.Errorf("%s:%d invalid highlight syntax", sourceFile, sourceLine)
+ }
+ highlight = cmd[hl[2]:hl[3]]
+ cmd = cmd[:hl[2]-2]
+ }
+
+ // Parse the remaining command line.
+ // Arguments:
+ // args[0]: whole match
+ // args[1]: .code/.play
+ // args[2]: flags ("-edit -numbers")
+ // args[3]: file name
+ // args[4]: optional address
+ args := codeRE.FindStringSubmatch(cmd)
+ if len(args) != 5 {
+ return nil, fmt.Errorf("%s:%d: syntax error for .code/.play invocation", sourceFile, sourceLine)
+ }
+ command, flags, file, addr := args[1], args[2], args[3], strings.TrimSpace(args[4])
+ play := command == "play" && PlayEnabled
+
+ // Read in code file and (optionally) match address.
+ filename := filepath.Join(filepath.Dir(sourceFile), file)
+ textBytes, err := ctx.ReadFile(filename)
+ if err != nil {
+ return nil, fmt.Errorf("%s:%d: %v", sourceFile, sourceLine, err)
+ }
+ lo, hi, err := addrToByteRange(addr, 0, textBytes)
+ if err != nil {
+ return nil, fmt.Errorf("%s:%d: %v", sourceFile, sourceLine, err)
+ }
+ if lo > hi {
+ // The search in addrToByteRange can wrap around so we might
+ // end up with the range ending before its starting point
+ hi, lo = lo, hi
+ }
+
+ // Acme pattern matches can stop mid-line,
+ // so run to end of line in both directions if not at line start/end.
+ for lo > 0 && textBytes[lo-1] != '\n' {
+ lo--
+ }
+ if hi > 0 {
+ for hi < len(textBytes) && textBytes[hi-1] != '\n' {
+ hi++
+ }
+ }
+
+ lines := codeLines(textBytes, lo, hi)
+
+ data := &codeTemplateData{
+ Lines: formatLines(lines, highlight),
+ Edit: strings.Contains(flags, "-edit"),
+ Numbers: strings.Contains(flags, "-numbers"),
+ }
+
+ // Include before and after in a hidden span for playground code.
+ if play {
+ data.Prefix = textBytes[:lo]
+ data.Suffix = textBytes[hi:]
+ }
+
+ var buf bytes.Buffer
+ if err := codeTemplate.Execute(&buf, data); err != nil {
+ return nil, err
+ }
+ return Code{
+ Cmd: origCmd,
+ Text: template.HTML(buf.String()),
+ Play: play,
+ Edit: data.Edit,
+ FileName: filepath.Base(filename),
+ Ext: filepath.Ext(filename),
+ Raw: rawCode(lines),
+ }, nil
+}
+
+// formatLines returns a new slice of codeLine with the given lines
+// replacing tabs with spaces and adding highlighting where needed.
+func formatLines(lines []codeLine, highlight string) []codeLine {
+ formatted := make([]codeLine, len(lines))
+ for i, line := range lines {
+ // Replace tabs with spaces, which work better in HTML.
+ line.L = strings.Replace(line.L, "\t", " ", -1)
+
+ // Highlight lines that end with "// HL[highlight]"
+ // and strip the magic comment.
+ if m := hlCommentRE.FindStringSubmatch(line.L); m != nil {
+ line.L = m[1]
+ line.HL = m[2] == highlight
+ }
+
+ formatted[i] = line
+ }
+ return formatted
+}
+
+// rawCode returns the code represented by the given codeLines without any kind
+// of formatting.
+func rawCode(lines []codeLine) []byte {
+ b := new(bytes.Buffer)
+ for _, line := range lines {
+ b.WriteString(line.L)
+ b.WriteByte('\n')
+ }
+ return b.Bytes()
+}
+
+type codeTemplateData struct {
+ Lines []codeLine
+ Prefix, Suffix []byte
+ Edit, Numbers bool
+}
+
+var leadingSpaceRE = regexp.MustCompile(`^[ \t]*`)
+
+var codeTemplate = template.Must(template.New("code").Funcs(template.FuncMap{
+ "trimSpace": strings.TrimSpace,
+ "leadingSpace": leadingSpaceRE.FindString,
+}).Parse(codeTemplateHTML))
+
+const codeTemplateHTML = `
+{{with .Prefix}}<pre style="display: none"><span>{{printf "%s" .}}</span></pre>{{end -}}
+
+<pre{{if .Edit}} contenteditable="true" spellcheck="false"{{end}}{{if .Numbers}} class="numbers"{{end}}>{{/*
+ */}}{{range .Lines}}<span num="{{.N}}">{{/*
+ */}}{{if .HL}}{{leadingSpace .L}}<b>{{trimSpace .L}}</b>{{/*
+ */}}{{else}}{{.L}}{{end}}{{/*
+*/}}</span>
+{{end}}</pre>
+{{with .Suffix}}<pre style="display: none"><span>{{printf "%s" .}}</span></pre>{{end -}}
+`
+
+// codeLine represents a line of code extracted from a source file.
+type codeLine struct {
+ L string // The line of code.
+ N int // The line number from the source file.
+ HL bool // Whether the line should be highlighted.
+}
+
+// codeLines takes a source file and returns the lines that
+// span the byte range specified by start and end.
+// It discards lines that end in "OMIT".
+func codeLines(src []byte, start, end int) (lines []codeLine) {
+ startLine := 1
+ for i, b := range src {
+ if i == start {
+ break
+ }
+ if b == '\n' {
+ startLine++
+ }
+ }
+ s := bufio.NewScanner(bytes.NewReader(src[start:end]))
+ for n := startLine; s.Scan(); n++ {
+ l := s.Text()
+ if strings.HasSuffix(l, "OMIT") {
+ continue
+ }
+ lines = append(lines, codeLine{L: l, N: n})
+ }
+ // Trim leading and trailing blank lines.
+ for len(lines) > 0 && len(lines[0].L) == 0 {
+ lines = lines[1:]
+ }
+ for len(lines) > 0 && len(lines[len(lines)-1].L) == 0 {
+ lines = lines[:len(lines)-1]
+ }
+ return
+}
+
+func parseArgs(name string, line int, args []string) (res []interface{}, err error) {
+ res = make([]interface{}, len(args))
+ for i, v := range args {
+ if len(v) == 0 {
+ return nil, fmt.Errorf("%s:%d bad code argument %q", name, line, v)
+ }
+ switch v[0] {
+ case '0', '1', '2', '3', '4', '5', '6', '7', '8', '9':
+ n, err := strconv.Atoi(v)
+ if err != nil {
+ return nil, fmt.Errorf("%s:%d bad code argument %q", name, line, v)
+ }
+ res[i] = n
+ case '/':
+ if len(v) < 2 || v[len(v)-1] != '/' {
+ return nil, fmt.Errorf("%s:%d bad code argument %q", name, line, v)
+ }
+ res[i] = v
+ case '$':
+ res[i] = "$"
+ case '_':
+ if len(v) == 1 {
+ // Do nothing; "_" indicates an intentionally empty parameter.
+ break
+ }
+ fallthrough
+ default:
+ return nil, fmt.Errorf("%s:%d bad code argument %q", name, line, v)
+ }
+ }
+ return
+}
projects / dotfiles / .git / blobdiff