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//! Renders the preview SVG for the README.
//!
//! To update the preview, execute the following command from the top level of
//! the repository:
//!
//! ```sh
//! cargo run --example readme_preview svg > codespan-reporting/assets/readme_preview.svg
//! ```
use codespan_reporting::diagnostic::{Diagnostic, Label};
use codespan_reporting::files::SimpleFile;
use codespan_reporting::term::termcolor::{Color, ColorSpec, StandardStream, WriteColor};
use codespan_reporting::term::{self, ColorArg};
use std::io::{self, Write};
use structopt::StructOpt;
#[derive(Debug, StructOpt)]
#[structopt(name = "emit")]
pub enum Opts {
/// Render SVG output
Svg,
/// Render Stderr output
Stderr {
/// Configure coloring of output
#[structopt(
long = "color",
parse(try_from_str),
default_value = "auto",
possible_values = ColorArg::VARIANTS,
case_insensitive = true
)]
color: ColorArg,
},
}
fn main() -> anyhow::Result<()> {
let file = SimpleFile::new(
"FizzBuzz.fun",
unindent::unindent(
r#"
module FizzBuzz where
fizz₁ : Nat → String
fizz₁ num = case (mod num 5) (mod num 3) of
0 0 => "FizzBuzz"
0 _ => "Fizz"
_ 0 => "Buzz"
_ _ => num
fizz₂ : Nat → String
fizz₂ num =
case (mod num 5) (mod num 3) of
0 0 => "FizzBuzz"
0 _ => "Fizz"
_ 0 => "Buzz"
_ _ => num
"#,
),
);
let diagnostics = [Diagnostic::error()
.with_message("`case` clauses have incompatible types")
.with_code("E0308")
.with_labels(vec![
Label::primary((), 328..331).with_message("expected `String`, found `Nat`"),
Label::secondary((), 211..331).with_message("`case` clauses have incompatible types"),
Label::secondary((), 258..268).with_message("this is found to be of type `String`"),
Label::secondary((), 284..290).with_message("this is found to be of type `String`"),
Label::secondary((), 306..312).with_message("this is found to be of type `String`"),
Label::secondary((), 186..192).with_message("expected type `String` found here"),
])
.with_notes(vec![unindent::unindent(
"
expected type `String`
found type `Nat`
",
)])];
// let mut files = SimpleFiles::new();
match Opts::from_args() {
Opts::Svg => {
let mut buffer = Vec::new();
let mut writer = HtmlEscapeWriter::new(SvgWriter::new(&mut buffer));
let config = codespan_reporting::term::Config {
styles: codespan_reporting::term::Styles::with_blue(Color::Blue),
..codespan_reporting::term::Config::default()
};
for diagnostic in &diagnostics {
term::emit(&mut writer, &config, &file, &diagnostic)?;
}
let num_lines = buffer.iter().filter(|byte| **byte == b'\n').count() + 1;
let padding = 10;
let font_size = 12;
let line_spacing = 3;
let width = 882;
let height = padding + num_lines * (font_size + line_spacing) + padding;
let stdout = std::io::stdout();
let writer = &mut stdout.lock();
write!(
writer,
<style>
pre {{
background: #1d1f21;
margin: 0;
padding: {padding}px;
border-radius: 6px;
color: #ffffff;
font: {font_size}px SFMono-Regular, Consolas, Liberation Mono, Menlo, monospace;
}}
pre .bold {{ font-weight: bold; }}
pre .fg.black {{ color: #1d1f21; }}
pre .fg.red {{ color: #cc6666; }}
pre .fg.green {{ color: #b5bd68; }}
pre .fg.yellow {{ color: #f0c674; }}
pre .fg.blue {{ color: #81a2be; }}
pre .fg.magenta {{ color: #b294bb; }}
pre .fg.cyan {{ color: #8abeb7; }}
pre .fg.white {{ color: #c5c8c6; }}
pre .fg.black.bright {{ color: #969896; }}
pre .fg.red.bright {{ color: #cc6666; }}
pre .fg.green.bright {{ color: #b5bd68; }}
pre .fg.yellow.bright {{ color: #f0c674; }}
pre .fg.blue.bright {{ color: #81a2be; }}
pre .fg.magenta.bright {{ color: #b294bb; }}
pre .fg.cyan.bright {{ color: #8abeb7; }}
pre .fg.white.bright {{ color: #ffffff; }}
pre .bg.black {{ background-color: #1d1f21; }}
pre .bg.red {{ background-color: #cc6666; }}
pre .bg.green {{ background-color: #b5bd68; }}
pre .bg.yellow {{ background-color: #f0c674; }}
pre .bg.blue {{ background-color: #81a2be; }}
pre .bg.magenta {{ background-color: #b294bb; }}
pre .bg.cyan {{ background-color: #8abeb7; }}
pre .bg.white {{ background-color: #c5c8c6; }}
pre .bg.black.bright {{ background-color: #969896; }}
pre .bg.red.bright {{ background-color: #cc6666; }}
pre .bg.green.bright {{ background-color: #b5bd68; }}
pre .bg.yellow.bright {{ background-color: #f0c674; }}
pre .bg.blue.bright {{ background-color: #81a2be; }}
pre .bg.magenta.bright {{ background-color: #b294bb; }}
pre .bg.cyan.bright {{ background-color: #8abeb7; }}
pre .bg.white.bright {{ background-color: #ffffff; }}
</style>
<foreignObject x="0" y="0" width="{width}" height="{height}">
<pre>"#,
padding = padding,
font_size = font_size,
width = width,
height = height,
)?;
writer.write_all(&buffer)?;
write!(
writer,
"</pre>
</div>
</foreignObject>
</svg>
"
)?;
}
Opts::Stderr { color } => {
let writer = StandardStream::stderr(color.into());
let config = codespan_reporting::term::Config::default();
for diagnostic in &diagnostics {
term::emit(&mut writer.lock(), &config, &file, &diagnostic)?;
}
}
}
Ok(())
}
/// Rudimentary HTML escaper which performs the following conversions:
///
/// - `<` ⇒ `<`
/// - `>` ⇒ `>`
/// - `&` ⇒ `&`
pub struct HtmlEscapeWriter<W> {
upstream: W,
}
impl<W> HtmlEscapeWriter<W> {
pub fn new(upstream: W) -> HtmlEscapeWriter<W> {
HtmlEscapeWriter { upstream }
}
}
impl<W: Write> Write for HtmlEscapeWriter<W> {
fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
let mut last_term = 0usize;
for (i, byte) in buf.iter().enumerate() {
let escape = match byte {
b'<' => &b"<"[..],
b'>' => &b">"[..],
b'&' => &b"&"[..],
_ => continue,
};
self.upstream.write_all(&buf[last_term..i])?;
last_term = i + 1;
self.upstream.write_all(escape)?;
}
self.upstream.write_all(&buf[last_term..])?;
Ok(buf.len())
}
fn flush(&mut self) -> io::Result<()> {
self.upstream.flush()
}
}
impl<W: WriteColor> WriteColor for HtmlEscapeWriter<W> {
fn supports_color(&self) -> bool {
self.upstream.supports_color()
}
fn set_color(&mut self, spec: &ColorSpec) -> io::Result<()> {
self.upstream.set_color(spec)
}
fn reset(&mut self) -> io::Result<()> {
self.upstream.reset()
}
}
pub struct SvgWriter<W> {
upstream: W,
color: ColorSpec,
}
impl<W> SvgWriter<W> {
pub fn new(upstream: W) -> SvgWriter<W> {
SvgWriter {
upstream,
color: ColorSpec::new(),
}
}
}
impl<W: Write> Write for SvgWriter<W> {
fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
self.upstream.write(buf)
}
fn flush(&mut self) -> io::Result<()> {
self.upstream.flush()
}
}
impl<W: Write> WriteColor for SvgWriter<W> {
fn supports_color(&self) -> bool {
true
}
fn set_color(&mut self, spec: &ColorSpec) -> io::Result<()> {
#![allow(unused_assignments)]
if self.color == *spec {
return Ok(());
} else {
if !self.color.is_none() {
write!(self, "</span>")?;
}
self.color = spec.clone();
}
if spec.is_none() {
write!(self, "</span>")?;
return Ok(());
} else {
write!(self, "<span class=\"")?;
}
let mut first = true;
fn write_first<W: Write>(first: bool, writer: &mut SvgWriter<W>) -> io::Result<bool> {
if !first {
write!(writer, " ")?;
}
Ok(false)
};
fn write_color<W: Write>(color: &Color, writer: &mut SvgWriter<W>) -> io::Result<()> {
match color {
Color::Black => write!(writer, "black"),
Color::Blue => write!(writer, "blue"),
Color::Green => write!(writer, "green"),
Color::Red => write!(writer, "red"),
Color::Cyan => write!(writer, "cyan"),
Color::Magenta => write!(writer, "magenta"),
Color::Yellow => write!(writer, "yellow"),
Color::White => write!(writer, "white"),
// TODO: other colors
_ => Ok(()),
}
};
if let Some(fg) = spec.fg() {
first = write_first(first, self)?;
write!(self, "fg ")?;
write_color(fg, self)?;
}
if let Some(bg) = spec.bg() {
first = write_first(first, self)?;
write!(self, "bg ")?;
write_color(bg, self)?;
}
if spec.bold() {
first = write_first(first, self)?;
write!(self, "bold")?;
}
if spec.underline() {
first = write_first(first, self)?;
write!(self, "underline")?;
}
if spec.intense() {
first = write_first(first, self)?;
write!(self, "bright")?;
}
write!(self, "\">")?;
Ok(())
}
fn reset(&mut self) -> io::Result<()> {
let color = self.color.clone();
if color != ColorSpec::new() {
write!(self, "</span>")?;
self.color = ColorSpec::new();
}
Ok(())
}
}