mdBook/src/utils/mod.rs

404 lines
11 KiB
Rust
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

#![allow(missing_docs)] // FIXME: Document this
pub mod fs;
mod string;
use errors::Error;
use regex::Regex;
use pulldown_cmark::{
html, Event, Options, Parser, Tag, OPTION_ENABLE_FOOTNOTES, OPTION_ENABLE_TABLES,
};
use std::borrow::Cow;
pub use self::string::{take_lines, RangeArgument};
/// Replaces multiple consecutive whitespace characters with a single space character.
pub fn collapse_whitespace<'a>(text: &'a str) -> Cow<'a, str> {
lazy_static! {
static ref RE: Regex = Regex::new(r"\s\s+").unwrap();
}
RE.replace_all(text, " ")
}
/// Convert the given string to a valid HTML element ID.
/// The only restriction is that the ID must not contain any ASCII whitespace.
pub fn normalize_id(content: &str) -> String {
content
.chars()
.filter_map(|ch| {
if ch.is_alphanumeric() || ch == '_' || ch == '-' {
Some(ch.to_ascii_lowercase())
} else if ch.is_whitespace() {
Some('-')
} else {
None
}
}).collect::<String>()
}
/// Generate an ID for use with anchors which is derived from a "normalised"
/// string.
pub fn id_from_content(content: &str) -> String {
let mut content = content.to_string();
// Skip any tags or html-encoded stuff
const REPL_SUB: &[&str] = &[
"<em>",
"</em>",
"<code>",
"</code>",
"<strong>",
"</strong>",
"&lt;",
"&gt;",
"&amp;",
"&#39;",
"&quot;",
];
for sub in REPL_SUB {
content = content.replace(sub, "");
}
// Remove spaces and hashes indicating a header
let trimmed = content.trim().trim_left_matches('#').trim();
normalize_id(trimmed)
}
fn adjust_links<'a>(event: Event<'a>, with_base: &str) -> Event<'a> {
lazy_static! {
static ref HTTP_LINK: Regex = Regex::new("^https?://").unwrap();
static ref MD_LINK: Regex = Regex::new(r"(?P<link>.*)\.md(?P<anchor>#.*)?").unwrap();
}
match event {
Event::Start(Tag::Link(dest, title)) => {
if !HTTP_LINK.is_match(&dest) {
let dest = if !with_base.is_empty() {
format!("{}/{}", with_base, dest)
} else {
dest.clone().into_owned()
};
if let Some(caps) = MD_LINK.captures(&dest) {
let mut html_link = [&caps["link"], ".html"].concat();
if let Some(anchor) = caps.name("anchor") {
html_link.push_str(anchor.as_str());
}
return Event::Start(Tag::Link(Cow::from(html_link), title));
}
}
Event::Start(Tag::Link(dest, title))
}
_ => event,
}
}
/// Wrapper around the pulldown-cmark parser for rendering markdown to HTML.
pub fn render_markdown(text: &str, curly_quotes: bool) -> String {
render_markdown_with_base(text, curly_quotes, "")
}
pub fn render_markdown_with_base(text: &str, curly_quotes: bool, base: &str) -> String {
let mut s = String::with_capacity(text.len() * 3 / 2);
let mut opts = Options::empty();
opts.insert(OPTION_ENABLE_TABLES);
opts.insert(OPTION_ENABLE_FOOTNOTES);
let p = Parser::new_ext(text, opts);
let mut converter = EventQuoteConverter::new(curly_quotes);
let events = p
.map(clean_codeblock_headers)
.map(|event| adjust_links(event, base))
.map(|event| converter.convert(event));
html::push_html(&mut s, events);
s
}
struct EventQuoteConverter {
enabled: bool,
convert_text: bool,
}
impl EventQuoteConverter {
fn new(enabled: bool) -> Self {
EventQuoteConverter {
enabled,
convert_text: true,
}
}
fn convert<'a>(&mut self, event: Event<'a>) -> Event<'a> {
if !self.enabled {
return event;
}
match event {
Event::Start(Tag::CodeBlock(_)) | Event::Start(Tag::Code) => {
self.convert_text = false;
event
}
Event::End(Tag::CodeBlock(_)) | Event::End(Tag::Code) => {
self.convert_text = true;
event
}
Event::Text(ref text) if self.convert_text => {
Event::Text(Cow::from(convert_quotes_to_curly(text)))
}
_ => event,
}
}
}
fn clean_codeblock_headers(event: Event) -> Event {
match event {
Event::Start(Tag::CodeBlock(ref info)) => {
let info: String = info.chars().filter(|ch| !ch.is_whitespace()).collect();
Event::Start(Tag::CodeBlock(Cow::from(info)))
}
_ => event,
}
}
fn convert_quotes_to_curly(original_text: &str) -> String {
// We'll consider the start to be "whitespace".
let mut preceded_by_whitespace = true;
original_text
.chars()
.map(|original_char| {
let converted_char = match original_char {
'\'' => {
if preceded_by_whitespace {
''
} else {
''
}
}
'"' => {
if preceded_by_whitespace {
'“'
} else {
'”'
}
}
_ => original_char,
};
preceded_by_whitespace = original_char.is_whitespace();
converted_char
}).collect()
}
/// Prints a "backtrace" of some `Error`.
pub fn log_backtrace(e: &Error) {
error!("Error: {}", e);
for cause in e.iter().skip(1) {
error!("\tCaused By: {}", cause);
}
}
#[cfg(test)]
mod tests {
mod render_markdown {
use super::super::render_markdown;
#[test]
fn preserves_external_links() {
assert_eq!(
render_markdown("[example](https://www.rust-lang.org/)", false),
"<p><a href=\"https://www.rust-lang.org/\">example</a></p>\n"
);
}
#[test]
fn it_can_adjust_markdown_links() {
assert_eq!(
render_markdown("[example](example.md)", false),
"<p><a href=\"example.html\">example</a></p>\n"
);
assert_eq!(
render_markdown("[example_anchor](example.md#anchor)", false),
"<p><a href=\"example.html#anchor\">example_anchor</a></p>\n"
);
// this anchor contains 'md' inside of it
assert_eq!(
render_markdown("[phantom data](foo.html#phantomdata)", false),
"<p><a href=\"foo.html#phantomdata\">phantom data</a></p>\n"
);
}
#[test]
fn it_can_keep_quotes_straight() {
assert_eq!(render_markdown("'one'", false), "<p>'one'</p>\n");
}
#[test]
fn it_can_make_quotes_curly_except_when_they_are_in_code() {
let input = r#"
'one'
```
'two'
```
`'three'` 'four'"#;
let expected = r#"<p>one</p>
<pre><code>'two'
</code></pre>
<p><code>'three'</code> four</p>
"#;
assert_eq!(render_markdown(input, true), expected);
}
#[test]
fn whitespace_outside_of_codeblock_header_is_preserved() {
let input = r#"
some text with spaces
```rust
fn main() {
// code inside is unchanged
}
```
more text with spaces
"#;
let expected = r#"<p>some text with spaces</p>
<pre><code class="language-rust">fn main() {
// code inside is unchanged
}
</code></pre>
<p>more text with spaces</p>
"#;
assert_eq!(render_markdown(input, false), expected);
assert_eq!(render_markdown(input, true), expected);
}
#[test]
fn rust_code_block_properties_are_passed_as_space_delimited_class() {
let input = r#"
```rust,no_run,should_panic,property_3
```
"#;
let expected =
r#"<pre><code class="language-rust,no_run,should_panic,property_3"></code></pre>
"#;
assert_eq!(render_markdown(input, false), expected);
assert_eq!(render_markdown(input, true), expected);
}
#[test]
fn rust_code_block_properties_with_whitespace_are_passed_as_space_delimited_class() {
let input = r#"
```rust, no_run,,,should_panic , ,property_3
```
"#;
let expected =
r#"<pre><code class="language-rust,no_run,,,should_panic,,property_3"></code></pre>
"#;
assert_eq!(render_markdown(input, false), expected);
assert_eq!(render_markdown(input, true), expected);
}
#[test]
fn rust_code_block_without_properties_has_proper_html_class() {
let input = r#"
```rust
```
"#;
let expected = r#"<pre><code class="language-rust"></code></pre>
"#;
assert_eq!(render_markdown(input, false), expected);
assert_eq!(render_markdown(input, true), expected);
let input = r#"
```rust
```
"#;
assert_eq!(render_markdown(input, false), expected);
assert_eq!(render_markdown(input, true), expected);
}
}
mod html_munging {
use super::super::{id_from_content, normalize_id};
#[test]
fn it_generates_anchors() {
assert_eq!(
id_from_content("## Method-call expressions"),
"method-call-expressions"
);
assert_eq!(id_from_content("## **Bold** title"), "bold-title");
assert_eq!(id_from_content("## `Code` title"), "code-title");
}
#[test]
fn it_generates_anchors_from_non_ascii_initial() {
assert_eq!(
id_from_content("## `--passes`: add more rustdoc passes"),
"--passes-add-more-rustdoc-passes"
);
assert_eq!(
id_from_content("## 中文標題 CJK title"),
"中文標題-cjk-title"
);
assert_eq!(id_from_content("## Über"), "Über");
}
#[test]
fn it_normalizes_ids() {
assert_eq!(
normalize_id("`--passes`: add more rustdoc passes"),
"--passes-add-more-rustdoc-passes"
);
assert_eq!(
normalize_id("Method-call 🐙 expressions \u{1f47c}"),
"method-call--expressions-"
);
assert_eq!(normalize_id("_-_12345"), "_-_12345");
assert_eq!(normalize_id("12345"), "12345");
assert_eq!(normalize_id("中文"), "中文");
assert_eq!(normalize_id("にほんご"), "にほんご");
assert_eq!(normalize_id("한국어"), "한국어");
assert_eq!(normalize_id(""), "");
}
}
mod convert_quotes_to_curly {
use super::super::convert_quotes_to_curly;
#[test]
fn it_converts_single_quotes() {
assert_eq!(
convert_quotes_to_curly("'one', 'two'"),
"one, two"
);
}
#[test]
fn it_converts_double_quotes() {
assert_eq!(
convert_quotes_to_curly(r#""one", "two""#),
"“one”, “two”"
);
}
#[test]
fn it_treats_tab_as_whitespace() {
assert_eq!(convert_quotes_to_curly("\t'one'"), "\tone");
}
}
}