From a1550a21c3da1428ce88d745181d2e0d46dcc47f Mon Sep 17 00:00:00 2001
From: mido <mido@numinix.com>
Date: Wed, 21 Jul 2021 07:41:23 -0700
Subject: [PATCH 1/3] catch out of bounds slice/array

---
 compiler.go       | 11 ++++++++++-
 variables_test.go | 10 ++++++++++
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/compiler.go b/compiler.go
index e71ac58..4fafe3f 100644
--- a/compiler.go
+++ b/compiler.go
@@ -355,7 +355,16 @@ func (c *compiler) evalAccessIndex(left, index interface{}, node *ast.IndexExpre
 				returnValue, err = c.evalIndexCallee(rv.Index(i), node)
 
 			} else {
-				returnValue = rv.Index(i).Interface()
+
+				if i >= 0 && i < rv.Len() {
+
+					returnValue = rv.Index(i).Interface()
+
+				} else {
+
+					err = fmt.Errorf("index out of range [%d] with length %d", index, rv.Len())
+
+				}
 			}
 
 		} else {
diff --git a/variables_test.go b/variables_test.go
index 6f9cce9..73ea9c2 100644
--- a/variables_test.go
+++ b/variables_test.go
@@ -153,3 +153,13 @@ func Test_Render_Let_ArrayAssign_OutofBoundsIndex(t *testing.T) {
 	r.Error(err)
 
 }
+
+func Test_Render_Access_Array_OutofBoundsIndex(t *testing.T) {
+	r := require.New(t)
+
+	input := `<% let a = [1, 2, "three", "four", 3.75] %><%= a[5]  %>`
+	_, err := Render(input, NewContext())
+	//r.Error(err)
+	r.Error(err)
+
+}

From 15f4fba302f2864ade92fef5d3d9964ad5811639 Mon Sep 17 00:00:00 2001
From: mido <mido@numinix.com>
Date: Wed, 21 Jul 2021 07:52:13 -0700
Subject: [PATCH 2/3] format the error message

---
 compiler.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compiler.go b/compiler.go
index 4fafe3f..092f00f 100644
--- a/compiler.go
+++ b/compiler.go
@@ -362,7 +362,7 @@ func (c *compiler) evalAccessIndex(left, index interface{}, node *ast.IndexExpre
 
 				} else {
 
-					err = fmt.Errorf("index out of range [%d] with length %d", index, rv.Len())
+					err = fmt.Errorf("array index out of bounds, got index %d, while array size is %d", index, rv.Len())
 
 				}
 			}

From 4148c2c8ebd95fc1f38a5666c0f49eb52b744b43 Mon Sep 17 00:00:00 2001
From: mido <mido@numinix.com>
Date: Wed, 27 Oct 2021 11:15:11 -0700
Subject: [PATCH 3/3] code cleanup

---
 compiler.go       | 3 ---
 variables_test.go | 7 -------
 2 files changed, 10 deletions(-)

diff --git a/compiler.go b/compiler.go
index 092f00f..17f570b 100644
--- a/compiler.go
+++ b/compiler.go
@@ -355,11 +355,8 @@ func (c *compiler) evalAccessIndex(left, index interface{}, node *ast.IndexExpre
 				returnValue, err = c.evalIndexCallee(rv.Index(i), node)
 
 			} else {
-
 				if i >= 0 && i < rv.Len() {
-
 					returnValue = rv.Index(i).Interface()
-
 				} else {
 
 					err = fmt.Errorf("array index out of bounds, got index %d, while array size is %d", index, rv.Len())
diff --git a/variables_test.go b/variables_test.go
index 73ea9c2..bda526b 100644
--- a/variables_test.go
+++ b/variables_test.go
@@ -121,8 +121,6 @@ func Test_Render_Let_ArrayAssign_InvalidKey(t *testing.T) {
 	input := `<p><% let a = [1, 2, "three", "four", 3.75] %><% a["b"] = 3 %><%= a["c"] %></p>`
 	_, err := Render(input, NewContext())
 	r.Error(err)
-	//r.NoError(err)
-	//r.Equal("<p></p>", s)
 }
 
 func Test_Render_Let_ArrayAssign_ValidIndex(t *testing.T) {
@@ -130,7 +128,6 @@ func Test_Render_Let_ArrayAssign_ValidIndex(t *testing.T) {
 
 	input := `<p><% let a = [1, 2, "three", "four", 3.75] %><% a[0] = 3 %><%= a[0] %></p>`
 	s, err := Render(input, NewContext())
-	//r.Error(err)
 	r.NoError(err)
 	r.Equal("<p>3</p>", s)
 }
@@ -140,7 +137,6 @@ func Test_Render_Let_ArrayAssign_Resultaddition(t *testing.T) {
 
 	input := `<p><% let a = [1, 2, "three", "four", 3.75] %><% a[4] = 3 %><%= a[4] + 2 %></p>`
 	s, err := Render(input, NewContext())
-	//r.Error(err)
 	r.NoError(err)
 	r.Equal("<p>5</p>", s)
 }
@@ -151,7 +147,6 @@ func Test_Render_Let_ArrayAssign_OutofBoundsIndex(t *testing.T) {
 	input := `<p><% let a = [1, 2, "three", "four", 3.75] %><% a[5] = 3 %><%= a[4] + 2 %></p>`
 	_, err := Render(input, NewContext())
 	r.Error(err)
-
 }
 
 func Test_Render_Access_Array_OutofBoundsIndex(t *testing.T) {
@@ -159,7 +154,5 @@ func Test_Render_Access_Array_OutofBoundsIndex(t *testing.T) {
 
 	input := `<% let a = [1, 2, "three", "four", 3.75] %><%= a[5]  %>`
 	_, err := Render(input, NewContext())
-	//r.Error(err)
 	r.Error(err)
-
 }