Add StripMarkdown option (irc). (#1145)

Enable `StripMarkdown` to strip markdown for irc.

1 files changed, 66 insertions, 0 deletions

diff --git a/vendor/github.com/writeas/go-strip-markdown/strip.go b/vendor/github.com/writeas/go-strip-markdown/strip.go
new file mode 100644
index 00000000..c20812f6
--- /dev/null
+++ b/vendor/github.com/writeas/go-strip-markdown/strip.go
@@ -0,0 +1,66 @@
+// Package stripmd strips Markdown from text
+package stripmd
+
+import (
+	"regexp"
+)
+
+var (
+	listLeadersReg = regexp.MustCompile(`(?m)^([\s\t]*)([\*\-\+]|\d\.)\s+`)
+
+	headerReg = regexp.MustCompile(`\n={2,}`)
+	strikeReg = regexp.MustCompile(`~~`)
+	codeReg   = regexp.MustCompile("`{3}" + `.*\n`)
+
+	htmlReg         = regexp.MustCompile("<(.*?)>")
+	emphReg         = regexp.MustCompile(`\*\*([^*]+)\*\*`)
+	emphReg2        = regexp.MustCompile(`\*([^*]+)\*`)
+	emphReg3        = regexp.MustCompile(`__([^_]+)__`)
+	emphReg4        = regexp.MustCompile(`_([^_]+)_`)
+	setextHeaderReg = regexp.MustCompile(`^[=\-]{2,}\s*$`)
+	footnotesReg    = regexp.MustCompile(`\[\^.+?\](\: .*?$)?`)
+	footnotes2Reg   = regexp.MustCompile(`\s{0,2}\[.*?\]: .*?$`)
+	imagesReg       = regexp.MustCompile(`\!\[(.*?)\]\s?[\[\(].*?[\]\)]`)
+	linksReg        = regexp.MustCompile(`\[(.*?)\][\[\(].*?[\]\)]`)
+	blockquoteReg   = regexp.MustCompile(`>\s*`)
+	refLinkReg      = regexp.MustCompile(`^\s{1,2}\[(.*?)\]: (\S+)( ".*?")?\s*$`)
+	atxHeaderReg    = regexp.MustCompile(`(?m)^\#{1,6}\s*([^#]+)\s*(\#{1,6})?$`)
+	atxHeaderReg2   = regexp.MustCompile(`([\*_]{1,3})(\S.*?\S)?P1`)
+	atxHeaderReg3   = regexp.MustCompile("(?m)(`{3,})" + `(.*?)?P1`)
+	atxHeaderReg4   = regexp.MustCompile(`^-{3,}\s*$`)
+	atxHeaderReg5   = regexp.MustCompile("`(.+?)`")
+	atxHeaderReg6   = regexp.MustCompile(`\n{2,}`)
+)
+
+// Strip returns the given string sans any Markdown.
+// Where necessary, elements are replaced with their best textual forms, so
+// for example, hyperlinks are stripped of their URL and become only the link
+// text, and images lose their URL and become only the alt text.
+func Strip(s string) string {
+	res := s
+	res = listLeadersReg.ReplaceAllString(res, "$1")
+
+	res = headerReg.ReplaceAllString(res, "\n")
+	res = strikeReg.ReplaceAllString(res, "")
+	res = codeReg.ReplaceAllString(res, "")
+
+	res = emphReg.ReplaceAllString(res, "$1")
+	res = emphReg2.ReplaceAllString(res, "$1")
+	res = emphReg3.ReplaceAllString(res, "$1")
+	res = emphReg4.ReplaceAllString(res, "$1")
+	res = htmlReg.ReplaceAllString(res, "$1")
+	res = setextHeaderReg.ReplaceAllString(res, "")
+	res = footnotesReg.ReplaceAllString(res, "")
+	res = footnotes2Reg.ReplaceAllString(res, "")
+	res = imagesReg.ReplaceAllString(res, "$1")
+	res = linksReg.ReplaceAllString(res, "$1")
+	res = blockquoteReg.ReplaceAllString(res, "  ")
+	res = refLinkReg.ReplaceAllString(res, "")
+	res = atxHeaderReg.ReplaceAllString(res, "$1")
+	res = atxHeaderReg2.ReplaceAllString(res, "$2")
+	res = atxHeaderReg3.ReplaceAllString(res, "$2")
+	res = atxHeaderReg4.ReplaceAllString(res, "")
+	res = atxHeaderReg5.ReplaceAllString(res, "$1")
+	res = atxHeaderReg6.ReplaceAllString(res, "\n\n")
+	return res
+}