Improve hovers for KCL std lib fns (#6208)

Signed-off-by: Nick Cameron <nrc@ncameron.org>

docs/kcl/std-helix.md

@@ -9,7 +9,15 @@ Create a helix.
 
 
 ```js
-helix(revolutions: number(_), angleStart: number(deg), ccw?: bool, radius?: number(mm), axis?: Axis3d | Edge, length?: number(mm), cylinder?: Solid): Helix
+helix(
+  revolutions: number(_),
+  angleStart: number(deg),
+  ccw?: bool,
+  radius?: number(mm),
+  axis?: Axis3d | Edge,
+  length?: number(mm),
+  cylinder?: Solid,
+): Helix
 ```
 
 

docs/kcl/std-math-polar.md

@@ -6,10 +6,14 @@ layout: manual
 
 
 
-Convert polar/sphere (azimuth, elevation, distance) coordinates tocartesian (x/y/z grid) coordinates.
+Convert polar/sphere (azimuth, elevation, distance) coordinates to
+cartesian (x/y/z grid) coordinates.
 
 ```js
-polar(angle: number(deg), length: number(mm)): [number(mm); 2]
+polar(
+  angle: number(deg),
+  length: number(mm),
+): [number(mm); 2]
 ```
 
 

docs/kcl/std-revolve.md

@@ -18,7 +18,14 @@ You can provide more than one sketch to revolve, and they will all be
 revolved around the same axis.
 
 ```js
-revolve(@sketches: [Sketch; 1+], axis: Axis2d | Edge, angle?: number(deg), tolerance?: number(mm), tagStart?: tag, tagEnd?: tag): Solid
+revolve(
+  @sketches: [Sketch; 1+],
+  axis: Axis2d | Edge,
+  angle?: number(deg),
+  tolerance?: number(mm),
+  tagStart?: tag,
+  tagEnd?: tag,
+): Solid
 ```
 
 

docs/kcl/std-sketch-circle.md

@@ -6,10 +6,16 @@ layout: manual
 
 
 
-Construct a 2-dimensional circle, of the specified radius, centered atthe provided (x, y) origin point.
+Construct a 2-dimensional circle, of the specified radius, centered at
+the provided (x, y) origin point.
 
 ```js
-circle(@sketch_or_surface: Sketch | Plane | Face, center: Point2d, radius: number, tag?: tag): Sketch
+circle(
+  @sketch_or_surface: Sketch | Plane | Face,
+  center: Point2d,
+  radius: number,
+  tag?: tag,
+): Sketch
 ```
 
 

docs/kcl/std-sketch-mirror2d.md

@@ -11,7 +11,10 @@ Only works on unclosed sketches for now.
 Mirror occurs around a local sketch axis rather than a global axis.
 
 ```js
-mirror2d(@sketches: [Sketch; 1+], axis: Axis2d | Edge): Sketch
+mirror2d(
+  @sketches: [Sketch; 1+],
+  axis: Axis2d | Edge,
+): Sketch
 ```
 
 

rust/kcl-lib/src/docs/kcl_doc.rs

@@ -1,4 +1,4 @@
-use std::{collections::HashSet, str::FromStr};
+use std::{collections::HashSet, fmt, str::FromStr};
 
 use regex::Regex;
 use tower_lsp::lsp_types::{
@@ -389,21 +389,23 @@ impl FnData {
     pub fn fn_signature(&self) -> String {
         let mut signature = String::new();
 
-        signature.push('(');
-        for (i, arg) in self.args.iter().enumerate() {
-            if i > 0 {
-                signature.push_str(", ");
-            }
-            match &arg.kind {
-                ArgKind::Special => signature.push_str(&format!("@{}", arg.name)),
-                ArgKind::Labelled(false) => signature.push_str(&arg.name),
-                ArgKind::Labelled(true) => signature.push_str(&format!("{}?", arg.name)),
-            }
-            if let Some(ty) = &arg.ty {
-                signature.push_str(&format!(": {ty}"));
+        if self.args.is_empty() {
+            signature.push_str("()");
+        } else if self.args.len() == 1 {
+            signature.push('(');
+            signature.push_str(&self.args[0].to_string());
+            signature.push(')');
+        } else {
+            signature.push('(');
+            for a in &self.args {
+                signature.push_str("\n  ");
+                signature.push_str(&a.to_string());
+                signature.push(',');
             }
+            signature.push('\n');
+            signature.push(')');
         }
-        signature.push(')');
+
         if let Some(ty) = &self.return_type {
             signature.push_str(&format!(": {ty}"));
         }
@@ -515,6 +517,20 @@ pub struct ArgData {
     pub docs: Option<String>,
 }
 
+impl fmt::Display for ArgData {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match &self.kind {
+            ArgKind::Special => write!(f, "@{}", self.name)?,
+            ArgKind::Labelled(false) => f.write_str(&self.name)?,
+            ArgKind::Labelled(true) => write!(f, "{}?", self.name)?,
+        }
+        if let Some(ty) = &self.ty {
+            write!(f, ": {ty}")?;
+        }
+        Ok(())
+    }
+}
+
 #[derive(Debug, Clone, Copy, PartialEq)]
 pub enum ArgKind {
     Special,
@@ -766,8 +782,8 @@ trait ApplyMeta {
                     description = summary;
                     summary = None;
                     let d = description.as_mut().unwrap();
-                    d.push_str(l);
                     d.push('\n');
+                    d.push_str(l);
                 }
                 continue;
             }