From c03f7006620882de9fdf9705c2c296dd80adcdfc Mon Sep 17 00:00:00 2001
From: JT <jonathan.d.turner@gmail.com>
Date: Sat, 17 Jul 2021 11:22:01 +1200
Subject: [PATCH] Add rest param

---
 src/parse_error.rs |  1 +
 src/parser.rs      | 27 ++++++++++++++++++++-------
 2 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/src/parse_error.rs b/src/parse_error.rs
index a418707118..d126eca336 100644
--- a/src/parse_error.rs
+++ b/src/parse_error.rs
@@ -8,6 +8,7 @@ pub enum ParseError {
     Unclosed(String, Span),
     UnknownStatement(Span),
     Mismatch(String, Span),
+    MultipleRestParams(Span),
     VariableNotFound(Span),
     UnknownCommand(Span),
     NonUtf8(Span),
diff --git a/src/parser.rs b/src/parser.rs
index 3d4ec2cf6a..75499dfaea 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -607,13 +607,16 @@ impl ParserWorkingSet {
             // Parse a positional arg if there is one
             if let Some(positional) = decl.signature.get_positional(positional_idx) {
                 //Make sure we leave enough spans for the remaining positionals
-                let remainder = decl.signature.num_positionals() - positional_idx;
 
-                let (arg, err) = self.parse_multispan_value(
-                    &spans[..(spans.len() - remainder + 1)],
-                    &mut spans_idx,
-                    positional.shape,
-                );
+                let end = if decl.signature.rest_positional.is_some() {
+                    spans.len()
+                } else {
+                    let remainder = decl.signature.num_positionals() - positional_idx;
+                    spans.len() - remainder + 1
+                };
+
+                let (arg, err) =
+                    self.parse_multispan_value(&spans[..end], &mut spans_idx, positional.shape);
                 error = error.or(err);
                 call.positional.push(arg);
                 positional_idx += 1;
@@ -1111,7 +1114,17 @@ impl ParserWorkingSet {
         for arg in args {
             match arg {
                 Arg::Positional(positional, required) => {
-                    if required {
+                    if positional.name == "...rest" {
+                        if sig.rest_positional.is_none() {
+                            sig.rest_positional = Some(PositionalArg {
+                                name: "rest".into(),
+                                ..positional
+                            })
+                        } else {
+                            // Too many rest params
+                            error = error.or(Some(ParseError::MultipleRestParams(span)))
+                        }
+                    } else if required {
                         sig.required_positional.push(positional)
                     } else {
                         sig.optional_positional.push(positional)