Basic image support 🖼

- [image] function
- Image rendering in tests
- Supports JPEG and PNG
- No PDF export so far

2 files changed, 59 insertions, 10 deletions

diff --git a/src/library/graphics.rs b/src/library/graphics.rs
new file mode 100644
index 00000000..779d78b5
--- /dev/null
+++ b/src/library/graphics.rs
@@ -0,0 +1,42 @@
+use std::fs::File;
+use std::io::BufReader;
+
+use image::io::Reader;
+
+use crate::layout::Image;
+use crate::prelude::*;
+
+/// `image`: Include an image.
+///
+/// # Positional arguments
+/// - The path to the image (string)
+pub fn image(mut args: Args, ctx: &mut EvalContext) -> Value {
+    let path = args.need::<_, Spanned<String>>(ctx, 0, "path");
+    let width = args.get::<_, Linear>(ctx, "width");
+    let height = args.get::<_, Linear>(ctx, "height");
+
+    if let Some(path) = path {
+        if let Ok(file) = File::open(path.v) {
+            match Reader::new(BufReader::new(file))
+                .with_guessed_format()
+                .map_err(|err| err.into())
+                .and_then(|reader| reader.decode())
+                .map(|img| img.into_rgba8())
+            {
+                Ok(buf) => {
+                    ctx.push(Image {
+                        buf,
+                        width,
+                        height,
+                        align: ctx.state.align,
+                    });
+                }
+                Err(err) => ctx.diag(error!(path.span, "invalid image: {}", err)),
+            }
+        } else {
+            ctx.diag(error!(path.span, "failed to open image file"));
+        }
+    }
+
+    Value::None
+}
diff --git a/src/library/mod.rs b/src/library/mod.rs
index af23d050..e59201dc 100644
--- a/src/library/mod.rs
+++ b/src/library/mod.rs
@@ -4,6 +4,7 @@ mod align;
 mod boxed;
 mod color;
 mod font;
+mod graphics;
 mod page;
 mod spacing;
 
@@ -11,29 +12,35 @@ pub use align::*;
 pub use boxed::*;
 pub use color::*;
 pub use font::*;
+pub use graphics::*;
 pub use page::*;
 pub use spacing::*;
 
 use crate::eval::{Scope, ValueFunc};
 
 macro_rules! std {
-    ($($name:literal => $func:expr),* $(,)?) => {
+    ($($func:expr $(=> $name:expr)?),* $(,)?) => {
         /// Create a scope with all standard library functions.
         pub fn _std() -> Scope {
             let mut std = Scope::new();
-            $(std.set($name, ValueFunc::new($func));)*
+            $(
+                let _name = stringify!($func);
+                $(let _name = $name;)?
+                std.set(_name, ValueFunc::new($func));
+            )*
             std
         }
     };
 }
 
 std! {
-    "align" => align,
-    "box" => boxed,
-    "font" => font,
-    "h" => h,
-    "page" => page,
-    "pagebreak" => pagebreak,
-    "rgb" => rgb,
-    "v" => v,
+    align,
+    boxed => "box",
+    font,
+    h,
+    image,
+    page,
+    pagebreak,
+    rgb,
+    v,
 }