Fix delimiting within <choose> and <layout> for CSL

src/csl/mod.rs

@@ -1674,6 +1674,9 @@ pub(crate) struct WritingContext {
     cases: NonEmptyStack<Option<TextCase>>,
     /// Inheritable name options.
     name_options: NonEmptyStack<InheritableNameOptions>,
+    /// Delimiters from ancestor delimiting elements (e.g., `cs:group`).
+    /// To be applied within `cs:choose`, but not another delimiting element or a macro.
+    delimiters: NonEmptyStack<Option<String>>,
 
     // Buffers.
     /// The buffer we're writing to. If block-level or formatting changes, we
@@ -1698,6 +1701,7 @@ impl Default for WritingContext {
             format_stack: NonEmptyStack::default(),
             cases: NonEmptyStack::default(),
             name_options: NonEmptyStack::default(),
+            delimiters: NonEmptyStack::default(),
             buf: CaseFolder::default(),
             elem_stack: NonEmptyStack::default(),
         }
@@ -1932,6 +1936,24 @@ impl WritingContext {
             .reconfigure((*self.cases.last()).map(Into::into).unwrap_or_default());
     }
 
+    /// Set the delimiter of the children of a [`citationberg::Group`] or
+    /// [`citationberg::Layout`]. It is inherited by [`citationberg::Choose`]
+    /// for its children as well.
+    fn push_delimiter(&mut self, delimiter: Option<String>) -> DelimiterIdx {
+        let idx = self.delimiters.len();
+        self.delimiters.push(delimiter);
+        DelimiterIdx(idx)
+    }
+    /// Clear the delimiter after a [`citationberg::Group`] or
+    /// [`citationberg::Layout`].
+    fn pop_delimiter(&mut self, idx: DelimiterIdx) {
+        if idx.0 == self.delimiters.len() {
+            return;
+        }
+
+        self.delimiters.drain(idx.0).for_each(drop);
+    }
+
     /// Push a new suppressed variable if we are suppressing queried variables.
     fn maybe_suppress(&self, variable: Variable) {
         if self.suppress_queried_variables {
@@ -2753,6 +2775,9 @@ impl DisplayLoc {
 #[must_use = "case stack must be popped"]
 struct CaseIdx(NonZeroUsize);
 
+#[must_use = "delimiter stack must be popped"]
+struct DelimiterIdx(NonZeroUsize);
+
 impl<T: EntryLike> Write for Context<'_, T> {
     fn write_str(&mut self, s: &str) -> std::fmt::Result {
         self.push_str(s);

src/csl/rendering/mod.rs

@@ -98,9 +98,12 @@ impl RenderCsl for citationberg::Text {
                 MaybeTyped::String(s) => ctx.push_str(&s.replace('-', "–")),
             },
             ResolvedTextTarget::Macro(mac) => {
+                // Delimiters from ancestor delimiting elements are NOT applied within.
+                let idx = ctx.writing.push_delimiter(None);
                 for child in &mac.children {
                     child.render(ctx);
                 }
+                ctx.writing.pop_delimiter(idx);
             }
             ResolvedTextTarget::Term(s) => ctx.push_str(s),
             ResolvedTextTarget::Value(val) => ctx.push_str(val),
@@ -831,7 +834,9 @@ where
 impl RenderCsl for citationberg::Choose {
     fn render<T: EntryLike>(&self, ctx: &mut Context<T>) {
         choose_children(self, ctx, |children, ctx| {
-            render_with_delimiter(children, self.delimiter.as_deref(), ctx);
+            // Propagate parent group's delimiter to 'choose' output, as
+            // required by CSL, by not pushing a delimiter to the stack.
+            render_with_delimiter(children, ctx);
         });
     }
 
@@ -859,11 +864,16 @@ impl RenderCsl for citationberg::Choose {
     }
 }
 
+/// Render `children` with the delimiter in `ctx` between them.
+///
+/// The delimiter can be updated by [`ctx.writing.push_delimiter`][super::WritingContext::push_delimiter]
+/// and [`ctx.writing.pop_delimiter`][super::WritingContext::pop_delimiter].
 fn render_with_delimiter<T: EntryLike>(
     children: &[LayoutRenderingElement],
-    delimiter: Option<&str>,
     ctx: &mut Context<T>,
 ) {
+    let delimiter = ctx.writing.delimiters.last().clone();
+
     let mut first = true;
     let mut loc = None;
 
@@ -874,7 +884,7 @@ fn render_with_delimiter<T: EntryLike>(
         }
 
         if !first {
-            if let Some(delim) = delimiter {
+            if let Some(delim) = &delimiter {
                 let prev_loc = std::mem::take(&mut loc);
 
                 if let Some(prev_loc) = prev_loc {
@@ -885,20 +895,10 @@ fn render_with_delimiter<T: EntryLike>(
                 ctx.push_str(delim);
             }
         }
+        first = false;
 
         let pos = ctx.push_elem(citationberg::Formatting::default());
-
-        match child {
-            LayoutRenderingElement::Text(text) => text.render(ctx),
-            LayoutRenderingElement::Number(num) => num.render(ctx),
-            LayoutRenderingElement::Label(label) => label.render(ctx),
-            LayoutRenderingElement::Date(date) => date.render(ctx),
-            LayoutRenderingElement::Names(names) => names.render(ctx),
-            LayoutRenderingElement::Choose(choose) => choose.render(ctx),
-            LayoutRenderingElement::Group(_group) => _group.render(ctx),
-        }
-
-        first = false;
+        child.render(ctx);
         ctx.commit_elem(pos, None, None);
     }
 
@@ -1147,7 +1147,10 @@ impl RenderCsl for citationberg::Group {
         let affix_loc = ctx.apply_prefix(&affixes);
 
         let info = self.will_have_info(ctx).1;
-        render_with_delimiter(&self.children, self.delimiter.as_deref(), ctx);
+
+        let delim_idx = ctx.writing.push_delimiter(self.delimiter.clone());
+        render_with_delimiter(&self.children, ctx);
+        ctx.writing.pop_delimiter(delim_idx);
 
         ctx.apply_suffix(&affixes, affix_loc);
 
@@ -1247,11 +1250,13 @@ impl RenderCsl for citationberg::LayoutRenderingElement {
 
 impl RenderCsl for citationberg::Layout {
     fn render<T: EntryLike>(&self, ctx: &mut Context<T>) {
-        let fidx = ctx.push_format(self.to_formatting());
+        let format_idx = ctx.push_format(self.to_formatting());
+        let delim_idx = ctx.writing.push_delimiter(self.delimiter.clone());
         for e in &self.elements {
             e.render(ctx);
         }
-        ctx.pop_format(fidx);
+        ctx.writing.pop_delimiter(delim_idx);
+        ctx.pop_format(format_idx);
     }
 
     fn will_render<T: EntryLike>(&self, ctx: &mut Context<T>, var: Variable) -> bool {

tests/local/choose_UseAncestorsDelimiter.txt

@@ -0,0 +1,82 @@
+>>===== MODE =====>>
+citation
+<<===== MODE =====<<
+
+
+>>===== DESCRIPTION =====>>
+Delimiters from the nearest delimiters from the nearest ancestor delimiting element (e.g., <group>)
+are applied within the output of <choose>
+(i.e., the output of the matching <if>, <else-if>, or <else>).
+https://docs.citationstyles.org/en/v1.0.2/specification.html#choose
+
+But they are not applied within the output of a delimiting element or a <text macro="…"> element.
+https://docs.citationstyles.org/en/v1.0.2/specification.html#delimiter
+https://docs.citationstyles.org/en/v1.0.2/specification.html#macro
+
+https://github.com/typst/hayagriva/issues/180
+<<===== DESCRIPTION =====<<
+
+
+>>===== RESULT =====>>
+Title_Edition_Publisher_Place_TitleEditionPublisherPlace_PublisherPublisherPublisher
+<<===== RESULT =====<<
+
+
+>>===== INPUT =====>>
+[
+    {
+        "edition": "Edition",
+        "id": "random",
+        "publisher": "Publisher",
+        "publisher-place": "Place",
+        "title": "Title",
+        "type": "book"
+    }
+]
+<<===== INPUT =====<<
+
+
+>>===== CSL =====>>
+<?xml version="1.0" encoding="utf-8"?>
+<style xmlns="http://purl.org/net/xbiblio/csl" version="1.0" class="in-text">
+  <info>
+    <id />
+    <title />
+  </info>
+  <macro name="unaffected">
+    <text variable="title"/> 
+    <text variable="edition"/>
+    <choose>
+      <if type="book">
+        <text variable="publisher"/>
+        <text variable="publisher-place"/>
+      </if>
+    </choose>
+  </macro>
+  <citation>
+    <layout>
+      <group delimiter="_">
+        <text variable="title"/> 
+        <text variable="edition"/>
+        <choose>
+          <if type="book">
+            <text variable="publisher"/>
+            <text variable="publisher-place"/>
+          </if>
+        </choose>
+        <text macro="unaffected"/>
+        <group>
+          <text variable="publisher"/>
+          <text variable="publisher"/>
+          <text variable="publisher"/>
+        </group>
+      </group>
+    </layout>
+  </citation>
+</style>
+<<===== CSL =====<<
+
+
+>>===== VERSION =====>>
+1.0.2
+<<===== VERSION =====<<