Pad function 🔲

6 files changed, 107 insertions, 75 deletions

diff --git a/src/exec/context.rs b/src/exec/context.rs
index b37b15cb..d491a251 100644
--- a/src/exec/context.rs
+++ b/src/exec/context.rs
@@ -80,6 +80,45 @@ impl<'a> ExecContext<'a> {
         self.inner.push(node);
     }
 
+    /// Push a normal word space.
+    pub fn push_space(&mut self) {
+        let em = self.state.font.font_size();
+        self.push(NodeSpacing {
+            amount: self.state.par.word_spacing.resolve(em),
+            softness: Softness::Soft,
+        });
+    }
+
+    /// Push text into the context.
+    ///
+    /// The text is split into lines at newlines.
+    pub fn push_text(&mut self, text: &str) {
+        let mut newline = false;
+        for line in text.split_terminator(is_newline) {
+            if newline {
+                self.apply_linebreak();
+            }
+
+            let node = self.make_text_node(line.into());
+            self.push(node);
+            newline = true;
+        }
+    }
+
+    /// Execute the body of a function and return the result as a stack node.
+    pub fn exec_body(&mut self, body: &ValueTemplate, expand: Spec<Expansion>) -> Node {
+        let dirs = self.state.dirs;
+        let align = self.state.align;
+
+        self.start_group(ContentGroup);
+        self.start_par_group();
+        body.exec(self);
+        self.end_par_group();
+        let children = self.end_group::<ContentGroup>().1;
+
+        NodeStack { dirs, align, expand, children }.into()
+    }
+
     /// Start a page group based on the active page state.
     ///
     /// The `softness` is a hint on whether empty pages should be kept in the
@@ -130,22 +169,6 @@ impl<'a> ExecContext<'a> {
         group.softness
     }
 
-    /// Start a content group.
-    ///
-    /// This also starts an inner paragraph.
-    pub fn start_content_group(&mut self) {
-        self.start_group(ContentGroup);
-        self.start_par_group();
-    }
-
-    /// End a content group and return the resulting nodes.
-    ///
-    /// This also ends an inner paragraph.
-    pub fn end_content_group(&mut self) -> Vec<Node> {
-        self.end_par_group();
-        self.end_group::<ContentGroup>().1
-    }
-
     /// Start a paragraph group based on the active text state.
     pub fn start_par_group(&mut self) {
         let em = self.state.font.font_size();
@@ -218,29 +241,28 @@ impl<'a> ExecContext<'a> {
         }
     }
 
-    /// Push a normal word space.
-    pub fn push_space(&mut self) {
+    /// Set the font to monospace.
+    pub fn apply_monospace(&mut self) {
+        let families = self.state.font.families_mut();
+        families.list.insert(0, "monospace".to_string());
+        families.flatten();
+    }
+
+    /// Apply a forced line break.
+    pub fn apply_linebreak(&mut self) {
+        self.end_par_group();
+        self.start_par_group();
+    }
+
+    /// Apply a forced paragraph break.
+    pub fn apply_parbreak(&mut self) {
+        self.end_par_group();
         let em = self.state.font.font_size();
         self.push(NodeSpacing {
-            amount: self.state.par.word_spacing.resolve(em),
+            amount: self.state.par.par_spacing.resolve(em),
             softness: Softness::Soft,
         });
-    }
-
-    /// Push text into the context.
-    ///
-    /// The text is split into lines at newlines.
-    pub fn push_text(&mut self, text: &str) {
-        let mut newline = false;
-        for line in text.split_terminator(is_newline) {
-            if newline {
-                self.apply_linebreak();
-            }
-
-            let node = self.make_text_node(line.into());
-            self.push(node);
-            newline = true;
-        }
+        self.start_par_group();
     }
 
     /// Construct a text node from the given string based on the active text
@@ -269,30 +291,6 @@ impl<'a> ExecContext<'a> {
             variant,
         }
     }
-
-    /// Set the font to monospace.
-    pub fn apply_monospace(&mut self) {
-        let families = self.state.font.families_mut();
-        families.list.insert(0, "monospace".to_string());
-        families.flatten();
-    }
-
-    /// Apply a forced line break.
-    pub fn apply_linebreak(&mut self) {
-        self.end_par_group();
-        self.start_par_group();
-    }
-
-    /// Apply a forced paragraph break.
-    pub fn apply_parbreak(&mut self) {
-        self.end_par_group();
-        let em = self.state.font.font_size();
-        self.push(NodeSpacing {
-            amount: self.state.par.par_spacing.resolve(em),
-            softness: Softness::Soft,
-        });
-        self.start_par_group();
-    }
 }
 
 /// Defines how an item interacts with surrounding items.
diff --git a/src/library/mod.rs b/src/library/mod.rs
index f846e6ee..54d6a14c 100644
--- a/src/library/mod.rs
+++ b/src/library/mod.rs
@@ -7,6 +7,7 @@ mod align;
 mod base;
 mod font;
 mod image;
+mod pad;
 mod page;
 mod shapes;
 mod spacing;
@@ -15,6 +16,7 @@ pub use self::image::*;
 pub use align::*;
 pub use base::*;
 pub use font::*;
+pub use pad::*;
 pub use page::*;
 pub use shapes::*;
 pub use spacing::*;
@@ -46,6 +48,7 @@ pub fn new() -> Scope {
     set!(func: "font", font);
     set!(func: "h", h);
     set!(func: "image", image);
+    set!(func: "pad", pad);
     set!(func: "page", page);
     set!(func: "pagebreak", pagebreak);
     set!(func: "repr", repr);
diff --git a/src/library/pad.rs b/src/library/pad.rs
new file mode 100644
index 00000000..f9e4386d
--- /dev/null
+++ b/src/library/pad.rs
@@ -0,0 +1,38 @@
+use super::*;
+
+/// `pad`: Pad content at the sides.
+///
+/// # Positional arguments
+/// - Padding for all sides: `padding`, of type `linear` relative to sides.
+/// - Body: of type `template`.
+///
+/// # Named arguments
+/// - Left padding:   `left`, of type `linear` relative to parent width.
+/// - Right padding:  `right`, of type `linear` relative to parent width.
+/// - Top padding:    `top`, of type `linear` relative to parent height.
+/// - Bottom padding: `bottom`, of type `linear` relative to parent height.
+pub fn pad(ctx: &mut EvalContext, args: &mut ValueArgs) -> Value {
+    let all = args.find(ctx);
+    let left = args.get(ctx, "left");
+    let top = args.get(ctx, "top");
+    let right = args.get(ctx, "right");
+    let bottom = args.get(ctx, "bottom");
+    let body = args.require::<ValueTemplate>(ctx, "body").unwrap_or_default();
+
+    let padding = Sides::new(
+        left.or(all).unwrap_or_default(),
+        top.or(all).unwrap_or_default(),
+        right.or(all).unwrap_or_default(),
+        bottom.or(all).unwrap_or_default(),
+    );
+
+    Value::template("pad", move |ctx| {
+        let snapshot = ctx.state.clone();
+
+        let expand = Spec::uniform(Expansion::Fit);
+        let child = ctx.exec_body(&body, expand);
+        ctx.push(NodePad { padding, child });
+
+        ctx.state = snapshot;
+    })
+}
diff --git a/src/library/shapes.rs b/src/library/shapes.rs
index f9685fce..5e638c01 100644
--- a/src/library/shapes.rs
+++ b/src/library/shapes.rs
@@ -24,28 +24,18 @@ pub fn box_(ctx: &mut EvalContext, args: &mut ValueArgs) -> Value {
     let main = args.get(ctx, "main-dir");
     let cross = args.get(ctx, "cross-dir");
     let color = args.get(ctx, "color");
-    let body = args.find::<ValueTemplate>(ctx);
+    let body = args.find::<ValueTemplate>(ctx).unwrap_or_default();
+
+    let fill_if = |c| if c { Expansion::Fill } else { Expansion::Fit };
+    let expand = Spec::new(fill_if(width.is_some()), fill_if(height.is_some()));
 
     Value::template("box", move |ctx| {
         let snapshot = ctx.state.clone();
 
         ctx.set_dirs(Gen::new(main, cross));
-        let dirs = ctx.state.dirs;
-        let align = ctx.state.align;
-
-        ctx.start_content_group();
-        if let Some(body) = &body {
-            body.exec(ctx);
-        }
-        let children = ctx.end_content_group();
 
-        let fill_if = |c| if c { Expansion::Fill } else { Expansion::Fit };
-        let expand = Spec::new(fill_if(width.is_some()), fill_if(height.is_some()));
-        let fixed = NodeFixed {
-            width,
-            height,
-            child: NodeStack { dirs, align, expand, children }.into(),
-        };
+        let child = ctx.exec_body(&body, expand);
+        let fixed = NodeFixed { width, height, child };
 
         if let Some(color) = color {
             ctx.push(NodeBackground {
diff --git a/tests/ref/library/pad.png b/tests/ref/library/pad.png
new file mode 100644
index 00000000..46380689
--- /dev/null
+++ b/tests/ref/library/pad.png
diff --git a/tests/typ/library/pad.typ b/tests/typ/library/pad.typ
new file mode 100644
index 00000000..3ee538c2
--- /dev/null
+++ b/tests/typ/library/pad.typ
@@ -0,0 +1,3 @@
+#box(color: #9feb52)[
+    #pad(10pt, box(color: #eb5278, width: 20pt, height: 20pt))
+]