From 382e835ed41f942e1676510bd9dc1f131f062403 Mon Sep 17 00:00:00 2001
From: Nate Moore <nate@astro.build>
Date: Fri, 15 Dec 2023 14:22:05 -0600
Subject: [PATCH] fix: handle nil pointer when expression is final node in file

---
 .changeset/big-crabs-burn.md     | 5 +++++
 internal/parser.go               | 3 +++
 internal/printer/printer_test.go | 7 +++++++
 3 files changed, 15 insertions(+)
 create mode 100644 .changeset/big-crabs-burn.md

diff --git a/.changeset/big-crabs-burn.md b/.changeset/big-crabs-burn.md
new file mode 100644
index 000000000..988075964
--- /dev/null
+++ b/.changeset/big-crabs-burn.md
@@ -0,0 +1,5 @@
+---
+'@astrojs/compiler': patch
+---
+
+Fixes a memory reference error when an expression is the final node in a file
diff --git a/internal/parser.go b/internal/parser.go
index c99d134d2..c4b426dac 100644
--- a/internal/parser.go
+++ b/internal/parser.go
@@ -2786,6 +2786,9 @@ func inExpressionIM(p *parser) bool {
 		p.addLoc()
 		p.oe.pop()
 		nextOpenElement := p.oe.top()
+		if nextOpenElement == nil {
+			return true
+		}
 		// only switch the insertion mode when we're no longer inside an expression
 		if !nextOpenElement.Parent.Expression {
 			p.im = textIM
diff --git a/internal/printer/printer_test.go b/internal/printer/printer_test.go
index 68eab698f..0bf42dc38 100644
--- a/internal/printer/printer_test.go
+++ b/internal/printer/printer_test.go
@@ -2950,6 +2950,13 @@ const items = ["Dog", "Cat", "Platipus"];
 				code: `${$$maybeRenderHead($$result)}<div data-astro-transition-persist="foo"${$$addAttribute($$renderTransition($$result, "peuy4xf7", "", "foo"), "data-astro-transition-scope")}></div>`,
 			},
 		},
+		{
+			name:   "trailing expression",
+			source: `<Component />{}`,
+			want: want{
+				code: `${$$renderComponent($$result,'Component',Component,{})}${(void 0)}`,
+			},
+		},
 	}
 
 	for _, tt := range tests {