feat(parser/renderer): support passthrough (#41)

support for:
- "single plus" (i.e., wrapping with `+`)
- "triple plus" (i.e., wrapping with `+++`)
- using the `pass:[]` and `pass:q[]` macros

Signed-off-by: Xavier Coulon <[email protected]>

.gitignore

@@ -57,3 +57,4 @@ tmp
 
 # exclude code coverage merged results
 coverage.txt
+*.html

LIMITATIONS.adoc

@@ -34,3 +34,19 @@ whereas Asciidoc/Asciidoctor will produce :
 <p><strong>some *nested bold</strong> content*.</p>
 ```
 
+== Passthroughs
+
+The Inline pass macro will not render nothing at all instead of an empty paragraph
+when the macro is empty. I.e.:
+
+````
+pass:[]
+````
+
+will produce no HTML element at all, whereas Asciidoc/Asciidoctor will produce :
+
+````
+<div class="paragraph">
+<p></p>
+</div>
+````

README.adoc

@@ -15,6 +15,7 @@ It is is available under the terms of the https://raw.githubusercontent.com/byte
 * Delimited Source Blocks (using the `+++```+++` delimiter, a.k.a "fences")
 * Literal blocks (paragraph starting with a space, with the "...." delimiter or with the `[literal]` attribute)
 * Quoted text (+bold+, _italic_ and `monospace`) and substitution prevention using the `\` escape character
+* Passtrough (wrapping with a single plus or a triple plus, or using the `pass:[]` or `pass:q[]` macros)
 * Unordered lists, using the `-` marker for simple lists, or the `\*` marker for nested lists (and `\**`, `\***`, etc. for the sublists)
 * External links in paragraphs (`https://`, `http://`, `ftp://`, `irc://`, `mailto:`)
 * Inline images in paragraphs (`image://`)

libasciidoc_test.go

@@ -13,7 +13,7 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-var _ = Describe("Rendering documents in HTML", func() {
+var _ = Describe("Documents", func() {
 
 	Context("Document Body", func() {
 

parser/asciidoc-grammar.peg

@@ -32,12 +32,16 @@ Preamble <- elements:(StandaloneBlock*) {
 // ------------------------------------------
 FrontMatter <- YamlFrontMatter 
 
-FrontMatter <- YamlFrontMatterToken content:(!YamlFrontMatterToken .)* YamlFrontMatterToken {
-    return types.NewYamlFrontMatter(content.([]interface{}))
+FrontMatter <- YamlFrontMatterToken content:(YamlFrontMatterContent) YamlFrontMatterToken {
+    return types.NewYamlFrontMatter(content.(string))
 }
 
 YamlFrontMatterToken  <- "---" EOL
 
+YamlFrontMatterContent <- (!YamlFrontMatterToken .)* {
+    return string(c.text), nil
+}
+
 // ------------------------------------------
 // Document Header
 // ------------------------------------------
@@ -65,7 +69,7 @@ DocumentAuthor <- WS* namePart1:(DocumentAuthorNamePart) namePart2:(DocumentAuth
 } 
 
 // "<" marks the beginning of the author email, and ";" is the authors separator
-DocumentAuthorNamePart <- !"<" !";" Word WS*
+DocumentAuthorNamePart <- !"<" !";" Characters WS*
 
 DocumentAuthorEmail <- "<" email:(!">" !EOL .)+ ">" 
 
@@ -216,11 +220,11 @@ InlineContent <- !FencedBlockDelimiter elements:(WS* InlineElement WS*)+ &EOL {
     return types.NewInlineContent(elements.([]interface{}))
 } 
 
-InlineElement <- InlineImage / QuotedText / ExternalLink / DocumentAttributeSubstitution / Word
+InlineElement <- Passthrough / InlineImage / QuotedText / ExternalLink / DocumentAttributeSubstitution / Characters
 
-// ------------------------------------------
-// Quoted Texts (bold, italic and monospace)
-// ------------------------------------------
+// ----------------------------------------------------------------------------
+// Quoted Texts (bold, italic and monospace) including substitution prevention
+// ----------------------------------------------------------------------------
 QuotedText <- BoldText / ItalicText / MonospaceText /
             EscapedBoldText / EscapedItalicText / EscapedMonospaceText
 
@@ -316,17 +320,42 @@ EscapedMonospaceTextUnbalancedPunctuation <-  backslashes:(`\` `\`*) "``" conten
 
 QuotedTextContent <- QuotedTextContentElement (WS+ QuotedTextContentElement)*
 
-QuotedTextContentElement <- QuotedText / QuotedTextWord / WordWithQuotePunctuation // word with quote punctuation is only accepted if nothing matched before, so we have a chance to stop
+QuotedTextContentElement <- QuotedText / QuotedTextCharacters / CharactersWithQuotePunctuation // word with quote punctuation is only accepted if nothing matched before, so we have a chance to stop
 
-QuotedTextWord <- (!NEWLINE !WS !"*" !"_" !"`" .)+ // cannot have "*", "_" or "`" within
-WordWithQuotePunctuation <- (!NEWLINE !WS  .)+ { // can have "*", "_" or "`" within, maybe because the user inserted another quote, or made an error (extra or missing space, for example)
+QuotedTextCharacters <- (!NEWLINE !WS !"*" !"_" !"`" .)+ // cannot have "*", "_" or "`" within
+CharactersWithQuotePunctuation <- (!NEWLINE !WS  .)+ { // can have "*", "_" or "`" within, maybe because the user inserted another quote, or made an error (extra or missing space, for example)
     return c.text, nil
 }
 
 // make sure unbalanced punctuation for quoted text is treated accordingly
 UnbalancedQuotePunctuation <- "*" / "_" / "`"
 
 
+// ------------------------------------------
+// Passthrough
+// ------------------------------------------
+Passthrough <- TriplePlusPassthrough / SinglePlusPassthrough / PassthroughMacro
+
+SinglePlusPassthrough <- "+" content:(!NEWLINE !"+" .)* "+" {
+    return types.NewPassthrough(types.SinglePlusPassthrough, content.([]interface{}))
+}
+
+TriplePlusPassthrough <- "+++" content:(!"+++" .)* "+++" {
+    return types.NewPassthrough(types.TriplePlusPassthrough, content.([]interface{}))
+}
+
+PassthroughMacro <- SimplePassthroughMacro / PassthroughWithQuotedText
+
+SimplePassthroughMacro <- "pass:[" content:(PassthroughMacroCharacter)* "]" {
+    return types.NewPassthrough(types.PassthroughMacro, content.([]interface{}))
+}
+
+PassthroughWithQuotedText <- "pass:q[" content:(QuotedText / PassthroughMacroCharacter)* "]" {
+    return types.NewPassthrough(types.PassthroughMacro, content.([]interface{}))
+}
+
+PassthroughMacroCharacter <- (!"]" .)
+
 // ------------------------------------------
 // Links
 // ------------------------------------------
@@ -422,16 +451,20 @@ ElementTitle <- "." !"." !WS title:(!NEWLINE .)+ EOL {
     return types.NewElementTitle(title.([]interface{}))
 }
 
+// ------------------------------------------
+// BlankLine
+// ------------------------------------------
+BlankLine <- !EOF WS* EOL {
+    return types.NewBlankLine()
+}
+
 // ------------------------------------------
 // Base Types
 // ------------------------------------------
-Word <- (!NEWLINE !WS .)+ {
+Characters <- (!NEWLINE !WS .)+ {
     return string(c.text), nil
 }
 
-BlankLine <- !EOF WS* EOL {
-    return types.NewBlankLine()
-}
 
 URL <- (!NEWLINE !WS !"[" !"]" .)+ {
     return string(c.text), nil