html: rm events/out from Writer

separate input/output from rendering state
This commit is contained in:
Noah Hellman 2023-03-17 19:13:00 +01:00
parent f5724fcc9c
commit 3d1b5f2115

View file

@ -39,7 +39,7 @@ impl Render for Renderer {
events: I, events: I,
out: W, out: W,
) -> std::fmt::Result { ) -> std::fmt::Result {
Writer::new(events, out).write() Writer::default().write(events, out)
} }
} }
@ -49,9 +49,7 @@ enum Raw {
Other, Other,
} }
struct Writer<'s, I: Iterator<Item = Event<'s>>, W> { struct Writer {
events: I,
out: W,
raw: Raw, raw: Raw,
img_alt_text: usize, img_alt_text: usize,
list_tightness: Vec<bool>, list_tightness: Vec<bool>,
@ -61,11 +59,9 @@ struct Writer<'s, I: Iterator<Item = Event<'s>>, W> {
close_para: bool, close_para: bool,
} }
impl<'s, I: Iterator<Item = Event<'s>>, W: std::fmt::Write> Writer<'s, I, W> { impl Default for Writer {
fn new(events: I, out: W) -> Self { fn default() -> Self {
Self { Self {
events,
out,
raw: Raw::None, raw: Raw::None,
img_alt_text: 0, img_alt_text: 0,
list_tightness: Vec::new(), list_tightness: Vec::new(),
@ -75,9 +71,15 @@ impl<'s, I: Iterator<Item = Event<'s>>, W: std::fmt::Write> Writer<'s, I, W> {
close_para: false, close_para: false,
} }
} }
}
fn write(&mut self) -> std::fmt::Result { impl Writer {
while let Some(e) = self.events.next() { fn write<'s>(
&mut self,
events: impl Iterator<Item = Event<'s>>,
mut out: impl std::fmt::Write,
) -> std::fmt::Result {
for e in events {
if matches!(&e, Event::Blankline | Event::Escape) { if matches!(&e, Event::Blankline | Event::Escape) {
continue; continue;
} }
@ -87,32 +89,30 @@ impl<'s, I: Iterator<Item = Event<'s>>, W: std::fmt::Write> Writer<'s, I, W> {
self.close_para = false; self.close_para = false;
if !matches!(&e, Event::End(Container::Footnote { .. })) { if !matches!(&e, Event::End(Container::Footnote { .. })) {
// no need to add href before para close // no need to add href before para close
self.out.write_str("</p>")?; out.write_str("</p>")?;
} }
} }
match e { match e {
Event::Start(c, attrs) => { Event::Start(c, attrs) => {
if c.is_block() && !self.first_line { if c.is_block() && !self.first_line {
self.out.write_char('\n')?; out.write_char('\n')?;
} }
if self.img_alt_text > 0 && !matches!(c, Container::Image(..)) { if self.img_alt_text > 0 && !matches!(c, Container::Image(..)) {
continue; continue;
} }
match &c { match &c {
Container::Blockquote => self.out.write_str("<blockquote")?, Container::Blockquote => out.write_str("<blockquote")?,
Container::List { kind, tight } => { Container::List { kind, tight } => {
self.list_tightness.push(*tight); self.list_tightness.push(*tight);
match kind { match kind {
ListKind::Unordered | ListKind::Task => { ListKind::Unordered | ListKind::Task => out.write_str("<ul")?,
self.out.write_str("<ul")?
}
ListKind::Ordered { ListKind::Ordered {
numbering, start, .. numbering, start, ..
} => { } => {
self.out.write_str("<ol")?; out.write_str("<ol")?;
if *start > 1 { if *start > 1 {
write!(self.out, r#" start="{}""#, start)?; write!(out, r#" start="{}""#, start)?;
} }
if let Some(ty) = match numbering { if let Some(ty) = match numbering {
Decimal => None, Decimal => None,
@ -121,65 +121,64 @@ impl<'s, I: Iterator<Item = Event<'s>>, W: std::fmt::Write> Writer<'s, I, W> {
RomanLower => Some('i'), RomanLower => Some('i'),
RomanUpper => Some('I'), RomanUpper => Some('I'),
} { } {
write!(self.out, r#" type="{}""#, ty)?; write!(out, r#" type="{}""#, ty)?;
} }
} }
} }
} }
Container::ListItem | Container::TaskListItem { .. } => { Container::ListItem | Container::TaskListItem { .. } => {
self.out.write_str("<li")?; out.write_str("<li")?;
} }
Container::DescriptionList => self.out.write_str("<dl")?, Container::DescriptionList => out.write_str("<dl")?,
Container::DescriptionDetails => self.out.write_str("<dd")?, Container::DescriptionDetails => out.write_str("<dd")?,
Container::Footnote { number, .. } => { Container::Footnote { number, .. } => {
assert!(self.footnote_number.is_none()); assert!(self.footnote_number.is_none());
self.footnote_number = Some((*number).try_into().unwrap()); self.footnote_number = Some((*number).try_into().unwrap());
if !self.encountered_footnote { if !self.encountered_footnote {
self.encountered_footnote = true; self.encountered_footnote = true;
self.out out.write_str("<section role=\"doc-endnotes\">\n<hr>\n<ol>\n")?;
.write_str("<section role=\"doc-endnotes\">\n<hr>\n<ol>\n")?;
} }
write!(self.out, "<li id=\"fn{}\">", number)?; write!(out, "<li id=\"fn{}\">", number)?;
continue; continue;
} }
Container::Table => self.out.write_str("<table")?, Container::Table => out.write_str("<table")?,
Container::TableRow { .. } => self.out.write_str("<tr")?, Container::TableRow { .. } => out.write_str("<tr")?,
Container::Section { .. } => self.out.write_str("<section")?, Container::Section { .. } => out.write_str("<section")?,
Container::Div { .. } => self.out.write_str("<div")?, Container::Div { .. } => out.write_str("<div")?,
Container::Paragraph => { Container::Paragraph => {
if matches!(self.list_tightness.last(), Some(true)) { if matches!(self.list_tightness.last(), Some(true)) {
continue; continue;
} }
self.out.write_str("<p")?; out.write_str("<p")?;
} }
Container::Heading { level, .. } => write!(self.out, "<h{}", level)?, Container::Heading { level, .. } => write!(out, "<h{}", level)?,
Container::TableCell { head: false, .. } => self.out.write_str("<td")?, Container::TableCell { head: false, .. } => out.write_str("<td")?,
Container::TableCell { head: true, .. } => self.out.write_str("<th")?, Container::TableCell { head: true, .. } => out.write_str("<th")?,
Container::Caption => self.out.write_str("<caption")?, Container::Caption => out.write_str("<caption")?,
Container::DescriptionTerm => self.out.write_str("<dt")?, Container::DescriptionTerm => out.write_str("<dt")?,
Container::CodeBlock { .. } => self.out.write_str("<pre")?, Container::CodeBlock { .. } => out.write_str("<pre")?,
Container::Span | Container::Math { .. } => self.out.write_str("<span")?, Container::Span | Container::Math { .. } => out.write_str("<span")?,
Container::Link(dst, ty) => { Container::Link(dst, ty) => {
if matches!(ty, LinkType::Span(SpanLinkType::Unresolved)) { if matches!(ty, LinkType::Span(SpanLinkType::Unresolved)) {
self.out.write_str("<a")?; out.write_str("<a")?;
} else { } else {
self.out.write_str(r#"<a href=""#)?; out.write_str(r#"<a href=""#)?;
if matches!(ty, LinkType::Email) { if matches!(ty, LinkType::Email) {
self.out.write_str("mailto:")?; out.write_str("mailto:")?;
} }
self.write_attr(dst)?; write_attr(dst, &mut out)?;
self.out.write_char('"')?; out.write_char('"')?;
} }
} }
Container::Image(..) => { Container::Image(..) => {
self.img_alt_text += 1; self.img_alt_text += 1;
if self.img_alt_text == 1 { if self.img_alt_text == 1 {
self.out.write_str("<img")?; out.write_str("<img")?;
} else { } else {
continue; continue;
} }
} }
Container::Verbatim => self.out.write_str("<code")?, Container::Verbatim => out.write_str("<code")?,
Container::RawBlock { format } | Container::RawInline { format } => { Container::RawBlock { format } | Container::RawInline { format } => {
self.raw = if format == &"html" { self.raw = if format == &"html" {
Raw::Html Raw::Html
@ -188,19 +187,19 @@ impl<'s, I: Iterator<Item = Event<'s>>, W: std::fmt::Write> Writer<'s, I, W> {
}; };
continue; continue;
} }
Container::Subscript => self.out.write_str("<sub")?, Container::Subscript => out.write_str("<sub")?,
Container::Superscript => self.out.write_str("<sup")?, Container::Superscript => out.write_str("<sup")?,
Container::Insert => self.out.write_str("<ins")?, Container::Insert => out.write_str("<ins")?,
Container::Delete => self.out.write_str("<del")?, Container::Delete => out.write_str("<del")?,
Container::Strong => self.out.write_str("<strong")?, Container::Strong => out.write_str("<strong")?,
Container::Emphasis => self.out.write_str("<em")?, Container::Emphasis => out.write_str("<em")?,
Container::Mark => self.out.write_str("<mark")?, Container::Mark => out.write_str("<mark")?,
} }
for (a, v) in attrs.iter().filter(|(a, _)| *a != "class") { for (a, v) in attrs.iter().filter(|(a, _)| *a != "class") {
write!(self.out, r#" {}=""#, a)?; write!(out, r#" {}=""#, a)?;
v.parts().try_for_each(|part| self.write_attr(part))?; v.parts().try_for_each(|part| write_attr(part, &mut out))?;
self.out.write_char('"')?; out.write_char('"')?;
} }
if let Container::Heading { if let Container::Heading {
@ -211,9 +210,9 @@ impl<'s, I: Iterator<Item = Event<'s>>, W: std::fmt::Write> Writer<'s, I, W> {
| Container::Section { id } = &c | Container::Section { id } = &c
{ {
if !attrs.iter().any(|(a, _)| a == "id") { if !attrs.iter().any(|(a, _)| a == "id") {
self.out.write_str(r#" id=""#)?; out.write_str(r#" id=""#)?;
self.write_attr(id)?; write_attr(id, &mut out)?;
self.out.write_char('"')?; out.write_char('"')?;
} }
} }
@ -229,7 +228,7 @@ impl<'s, I: Iterator<Item = Event<'s>>, W: std::fmt::Write> Writer<'s, I, W> {
| Container::TaskListItem { .. } | Container::TaskListItem { .. }
) )
{ {
self.out.write_str(r#" class=""#)?; out.write_str(r#" class=""#)?;
let mut first_written = false; let mut first_written = false;
if let Some(cls) = match c { if let Some(cls) = match c {
Container::List { Container::List {
@ -243,7 +242,7 @@ impl<'s, I: Iterator<Item = Event<'s>>, W: std::fmt::Write> Writer<'s, I, W> {
_ => None, _ => None,
} { } {
first_written = true; first_written = true;
self.out.write_str(cls)?; out.write_str(cls)?;
} }
for cls in attrs for cls in attrs
.iter() .iter()
@ -251,19 +250,20 @@ impl<'s, I: Iterator<Item = Event<'s>>, W: std::fmt::Write> Writer<'s, I, W> {
.map(|(_, cls)| cls) .map(|(_, cls)| cls)
{ {
if first_written { if first_written {
self.out.write_char(' ')?; out.write_char(' ')?;
} }
first_written = true; first_written = true;
cls.parts().try_for_each(|part| self.write_attr(part))?; cls.parts()
.try_for_each(|part| write_attr(part, &mut out))?;
} }
// div class goes after classes from attrs // div class goes after classes from attrs
if let Container::Div { class: Some(cls) } = c { if let Container::Div { class: Some(cls) } = c {
if first_written { if first_written {
self.out.write_char(' ')?; out.write_char(' ')?;
} }
self.out.write_str(cls)?; out.write_str(cls)?;
} }
self.out.write_char('"')?; out.write_char('"')?;
} }
match c { match c {
@ -276,102 +276,101 @@ impl<'s, I: Iterator<Item = Event<'s>>, W: std::fmt::Write> Writer<'s, I, W> {
Alignment::Center => "center", Alignment::Center => "center",
Alignment::Right => "right", Alignment::Right => "right",
}; };
write!(self.out, r#" style="text-align: {};">"#, a)?; write!(out, r#" style="text-align: {};">"#, a)?;
} }
Container::CodeBlock { lang } => { Container::CodeBlock { lang } => {
if let Some(l) = lang { if let Some(l) = lang {
self.out.write_str(r#"><code class="language-"#)?; out.write_str(r#"><code class="language-"#)?;
self.write_attr(l)?; write_attr(l, &mut out)?;
self.out.write_str(r#"">"#)?; out.write_str(r#"">"#)?;
} else { } else {
self.out.write_str("><code>")?; out.write_str("><code>")?;
} }
} }
Container::Image(..) => { Container::Image(..) => {
if self.img_alt_text == 1 { if self.img_alt_text == 1 {
self.out.write_str(r#" alt=""#)?; out.write_str(r#" alt=""#)?;
} }
} }
Container::Math { display } => { Container::Math { display } => {
self.out out.write_str(if display { r#">\["# } else { r#">\("# })?;
.write_str(if display { r#">\["# } else { r#">\("# })?;
} }
_ => self.out.write_char('>')?, _ => out.write_char('>')?,
} }
} }
Event::End(c) => { Event::End(c) => {
if c.is_block_container() && !matches!(c, Container::Footnote { .. }) { if c.is_block_container() && !matches!(c, Container::Footnote { .. }) {
self.out.write_char('\n')?; out.write_char('\n')?;
} }
if self.img_alt_text > 0 && !matches!(c, Container::Image(..)) { if self.img_alt_text > 0 && !matches!(c, Container::Image(..)) {
continue; continue;
} }
match c { match c {
Container::Blockquote => self.out.write_str("</blockquote>")?, Container::Blockquote => out.write_str("</blockquote>")?,
Container::List { Container::List {
kind: ListKind::Unordered | ListKind::Task, kind: ListKind::Unordered | ListKind::Task,
.. ..
} => { } => {
self.list_tightness.pop(); self.list_tightness.pop();
self.out.write_str("</ul>")?; out.write_str("</ul>")?;
} }
Container::List { Container::List {
kind: ListKind::Ordered { .. }, kind: ListKind::Ordered { .. },
.. ..
} => self.out.write_str("</ol>")?, } => out.write_str("</ol>")?,
Container::ListItem | Container::TaskListItem { .. } => { Container::ListItem | Container::TaskListItem { .. } => {
self.out.write_str("</li>")?; out.write_str("</li>")?;
} }
Container::DescriptionList => self.out.write_str("</dl>")?, Container::DescriptionList => out.write_str("</dl>")?,
Container::DescriptionDetails => self.out.write_str("</dd>")?, Container::DescriptionDetails => out.write_str("</dd>")?,
Container::Footnote { number, .. } => { Container::Footnote { number, .. } => {
if !close_para { if !close_para {
// create a new paragraph // create a new paragraph
self.out.write_str("\n<p>")?; out.write_str("\n<p>")?;
} }
write!( write!(
self.out, out,
r##"<a href="#fnref{}" role="doc-backlink">↩︎︎</a></p>"##, r##"<a href="#fnref{}" role="doc-backlink">↩︎︎</a></p>"##,
number, number,
)?; )?;
self.out.write_str("\n</li>")?; out.write_str("\n</li>")?;
self.footnote_number = None; self.footnote_number = None;
} }
Container::Table => self.out.write_str("</table>")?, Container::Table => out.write_str("</table>")?,
Container::TableRow { .. } => self.out.write_str("</tr>")?, Container::TableRow { .. } => out.write_str("</tr>")?,
Container::Section { .. } => self.out.write_str("</section>")?, Container::Section { .. } => out.write_str("</section>")?,
Container::Div { .. } => self.out.write_str("</div>")?, Container::Div { .. } => out.write_str("</div>")?,
Container::Paragraph => { Container::Paragraph => {
if matches!(self.list_tightness.last(), Some(true)) { if matches!(self.list_tightness.last(), Some(true)) {
continue; continue;
} }
if self.footnote_number.is_none() { if self.footnote_number.is_none() {
self.out.write_str("</p>")?; out.write_str("</p>")?;
} else { } else {
self.close_para = true; self.close_para = true;
} }
} }
Container::Heading { level, .. } => write!(self.out, "</h{}>", level)?, Container::Heading { level, .. } => write!(out, "</h{}>", level)?,
Container::TableCell { head: false, .. } => self.out.write_str("</td>")?, Container::TableCell { head: false, .. } => out.write_str("</td>")?,
Container::TableCell { head: true, .. } => self.out.write_str("</th>")?, Container::TableCell { head: true, .. } => out.write_str("</th>")?,
Container::Caption => self.out.write_str("</caption>")?, Container::Caption => out.write_str("</caption>")?,
Container::DescriptionTerm => self.out.write_str("</dt>")?, Container::DescriptionTerm => out.write_str("</dt>")?,
Container::CodeBlock { .. } => self.out.write_str("</code></pre>")?, Container::CodeBlock { .. } => out.write_str("</code></pre>")?,
Container::Span => self.out.write_str("</span>")?, Container::Span => out.write_str("</span>")?,
Container::Link(..) => self.out.write_str("</a>")?, Container::Link(..) => out.write_str("</a>")?,
Container::Image(src, ..) => { Container::Image(src, ..) => {
if self.img_alt_text == 1 { if self.img_alt_text == 1 {
if !src.is_empty() { if !src.is_empty() {
self.out.write_str(r#"" src=""#)?; out.write_str(r#"" src=""#)?;
self.write_attr(&src)?; write_attr(&src, &mut out)?;
} }
self.out.write_str(r#"">"#)?; out.write_str(r#"">"#)?;
} }
self.img_alt_text -= 1; self.img_alt_text -= 1;
} }
Container::Verbatim => self.out.write_str("</code>")?, Container::Verbatim => out.write_str("</code>")?,
Container::Math { display } => { Container::Math { display } => {
self.out.write_str(if display { out.write_str(if display {
r#"\]</span>"# r#"\]</span>"#
} else { } else {
r#"\)</span>"# r#"\)</span>"#
@ -380,88 +379,97 @@ impl<'s, I: Iterator<Item = Event<'s>>, W: std::fmt::Write> Writer<'s, I, W> {
Container::RawBlock { .. } | Container::RawInline { .. } => { Container::RawBlock { .. } | Container::RawInline { .. } => {
self.raw = Raw::None; self.raw = Raw::None;
} }
Container::Subscript => self.out.write_str("</sub>")?, Container::Subscript => out.write_str("</sub>")?,
Container::Superscript => self.out.write_str("</sup>")?, Container::Superscript => out.write_str("</sup>")?,
Container::Insert => self.out.write_str("</ins>")?, Container::Insert => out.write_str("</ins>")?,
Container::Delete => self.out.write_str("</del>")?, Container::Delete => out.write_str("</del>")?,
Container::Strong => self.out.write_str("</strong>")?, Container::Strong => out.write_str("</strong>")?,
Container::Emphasis => self.out.write_str("</em>")?, Container::Emphasis => out.write_str("</em>")?,
Container::Mark => self.out.write_str("</mark>")?, Container::Mark => out.write_str("</mark>")?,
} }
} }
Event::Str(s) => match self.raw { Event::Str(s) => match self.raw {
Raw::None if self.img_alt_text > 0 => self.write_attr(&s)?, Raw::None if self.img_alt_text > 0 => write_attr(&s, &mut out)?,
Raw::None => self.write_text(&s)?, Raw::None => write_text(&s, &mut out)?,
Raw::Html => self.out.write_str(&s)?, Raw::Html => out.write_str(&s)?,
Raw::Other => {} Raw::Other => {}
}, },
Event::FootnoteReference(_tag, number) => { Event::FootnoteReference(_tag, number) => {
if self.img_alt_text == 0 { if self.img_alt_text == 0 {
write!( write!(
self.out, out,
r##"<a id="fnref{}" href="#fn{}" role="doc-noteref"><sup>{}</sup></a>"##, r##"<a id="fnref{}" href="#fn{}" role="doc-noteref"><sup>{}</sup></a>"##,
number, number, number number, number, number
)?; )?;
} }
} }
Event::Symbol(sym) => write!(self.out, ":{}:", sym)?, Event::Symbol(sym) => write!(out, ":{}:", sym)?,
Event::LeftSingleQuote => self.out.write_str("&lsquo;")?, Event::LeftSingleQuote => out.write_str("&lsquo;")?,
Event::RightSingleQuote => self.out.write_str("&rsquo;")?, Event::RightSingleQuote => out.write_str("&rsquo;")?,
Event::LeftDoubleQuote => self.out.write_str("&ldquo;")?, Event::LeftDoubleQuote => out.write_str("&ldquo;")?,
Event::RightDoubleQuote => self.out.write_str("&rdquo;")?, Event::RightDoubleQuote => out.write_str("&rdquo;")?,
Event::Ellipsis => self.out.write_str("&hellip;")?, Event::Ellipsis => out.write_str("&hellip;")?,
Event::EnDash => self.out.write_str("&ndash;")?, Event::EnDash => out.write_str("&ndash;")?,
Event::EmDash => self.out.write_str("&mdash;")?, Event::EmDash => out.write_str("&mdash;")?,
Event::NonBreakingSpace => self.out.write_str("&nbsp;")?, Event::NonBreakingSpace => out.write_str("&nbsp;")?,
Event::Hardbreak => self.out.write_str("<br>\n")?, Event::Hardbreak => out.write_str("<br>\n")?,
Event::Softbreak => self.out.write_char('\n')?, Event::Softbreak => out.write_char('\n')?,
Event::Escape | Event::Blankline => unreachable!("filtered out"), Event::Escape | Event::Blankline => unreachable!("filtered out"),
Event::ThematicBreak(attrs) => { Event::ThematicBreak(attrs) => {
self.out.write_str("\n<hr")?; out.write_str("\n<hr")?;
for (a, v) in attrs.iter() { for (a, v) in attrs.iter() {
write!(self.out, r#" {}=""#, a)?; write!(out, r#" {}=""#, a)?;
v.parts().try_for_each(|part| self.write_attr(part))?; v.parts().try_for_each(|part| write_attr(part, &mut out))?;
self.out.write_char('"')?; out.write_char('"')?;
} }
self.out.write_str(">")?; out.write_str(">")?;
} }
} }
self.first_line = false; self.first_line = false;
} }
if self.encountered_footnote { if self.encountered_footnote {
self.out.write_str("\n</ol>\n</section>")?; out.write_str("\n</ol>\n</section>")?;
} }
self.out.write_char('\n')?; out.write_char('\n')?;
Ok(()) Ok(())
} }
}
fn write_escape(&mut self, mut s: &str, escape_quotes: bool) -> std::fmt::Result {
let mut ent = ""; fn write_text<W>(s: &str, out: W) -> std::fmt::Result
while let Some(i) = s.find(|c| { where
match c { W: std::fmt::Write,
'<' => Some("&lt;"), {
'>' => Some("&gt;"), write_escape(s, false, out)
'&' => Some("&amp;"), }
'"' if escape_quotes => Some("&quot;"),
_ => None, fn write_attr<W>(s: &str, out: W) -> std::fmt::Result
} where
.map_or(false, |s| { W: std::fmt::Write,
ent = s; {
true write_escape(s, true, out)
}) }
}) {
self.out.write_str(&s[..i])?; fn write_escape<W>(mut s: &str, escape_quotes: bool, mut out: W) -> std::fmt::Result
self.out.write_str(ent)?; where
s = &s[i + 1..]; W: std::fmt::Write,
} {
self.out.write_str(s) let mut ent = "";
} while let Some(i) = s.find(|c| {
match c {
fn write_text(&mut self, s: &str) -> std::fmt::Result { '<' => Some("&lt;"),
self.write_escape(s, false) '>' => Some("&gt;"),
} '&' => Some("&amp;"),
'"' if escape_quotes => Some("&quot;"),
fn write_attr(&mut self, s: &str) -> std::fmt::Result { _ => None,
self.write_escape(s, true) }
} .map_or(false, |s| {
ent = s;
true
})
}) {
out.write_str(&s[..i])?;
out.write_str(ent)?;
s = &s[i + 1..];
}
out.write_str(s)
} }