From 361d848e26c6fcb36d0a3ee62442504306752a2a Mon Sep 17 00:00:00 2001
From: Daniel Richter <danny@1011i.com>
Date: Mon, 11 Dec 2023 17:53:45 -0800
Subject: [PATCH 1/2] Add benchmark for valid identifier check

---
 contest_test.go | 18 ++++++++++++++++++
 context.go      | 20 ++++++++++++++++++++
 2 files changed, 38 insertions(+)
 create mode 100644 contest_test.go

diff --git a/contest_test.go b/contest_test.go
new file mode 100644
index 0000000..3f1a10c
--- /dev/null
+++ b/contest_test.go
@@ -0,0 +1,18 @@
+package pongo2
+
+import "testing"
+
+func BenchmarkCheckForValidIdentifiers(b *testing.B) {
+	input := `valid_key`
+
+	b.Run("regex", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			isValidIdentifierRegex(input)
+		}
+	})
+	b.Run("char_check", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			isValidIdentifierCharCheck(input)
+		}
+	})
+}
diff --git a/context.go b/context.go
index 525ac3a..aa40861 100644
--- a/context.go
+++ b/context.go
@@ -40,6 +40,26 @@ func (c Context) checkForValidIdentifiers() *Error {
 	return nil
 }
 
+func isValidIdentifierRegex(s string) bool {
+	return reIdentifiers.MatchString(s)
+}
+
+func isValidIdentifierCharCheck(s string) bool {
+	for i := range s {
+		if !isValidIdentifierChar(s[i]) {
+			return false
+		}
+	}
+	return true
+}
+
+func isValidIdentifierChar(c byte) bool {
+	return (c >= 'a' && c <= 'z') ||
+		(c >= 'A' && c <= 'Z') ||
+		(c >= '0' && c <= '9') ||
+		c == '_'
+}
+
 // Update updates this context with the key/value-pairs from another context.
 func (c Context) Update(other Context) Context {
 	for k, v := range other {

From c0cb743a6c1222e980e961f1dcff71cc7eb9da14 Mon Sep 17 00:00:00 2001
From: Daniel Richter <danny@1011i.com>
Date: Mon, 11 Dec 2023 17:56:32 -0800
Subject: [PATCH 2/2] Switch valid identifier check to faster alternative

---
 contest_test.go | 18 ------------------
 context.go      | 11 ++---------
 2 files changed, 2 insertions(+), 27 deletions(-)
 delete mode 100644 contest_test.go

diff --git a/contest_test.go b/contest_test.go
deleted file mode 100644
index 3f1a10c..0000000
--- a/contest_test.go
+++ /dev/null
@@ -1,18 +0,0 @@
-package pongo2
-
-import "testing"
-
-func BenchmarkCheckForValidIdentifiers(b *testing.B) {
-	input := `valid_key`
-
-	b.Run("regex", func(b *testing.B) {
-		for i := 0; i < b.N; i++ {
-			isValidIdentifierRegex(input)
-		}
-	})
-	b.Run("char_check", func(b *testing.B) {
-		for i := 0; i < b.N; i++ {
-			isValidIdentifierCharCheck(input)
-		}
-	})
-}
diff --git a/context.go b/context.go
index aa40861..3ebf18f 100644
--- a/context.go
+++ b/context.go
@@ -3,11 +3,8 @@ package pongo2
 import (
 	"errors"
 	"fmt"
-	"regexp"
 )
 
-var reIdentifiers = regexp.MustCompile("^[a-zA-Z0-9_]+$")
-
 var autoescape = true
 
 func SetAutoescape(newValue bool) {
@@ -30,7 +27,7 @@ type Context map[string]any
 
 func (c Context) checkForValidIdentifiers() *Error {
 	for k, v := range c {
-		if !reIdentifiers.MatchString(k) {
+		if !isValidIdentifier(k) {
 			return &Error{
 				Sender:    "checkForValidIdentifiers",
 				OrigError: fmt.Errorf("context-key '%s' (value: '%+v') is not a valid identifier", k, v),
@@ -40,11 +37,7 @@ func (c Context) checkForValidIdentifiers() *Error {
 	return nil
 }
 
-func isValidIdentifierRegex(s string) bool {
-	return reIdentifiers.MatchString(s)
-}
-
-func isValidIdentifierCharCheck(s string) bool {
+func isValidIdentifier(s string) bool {
 	for i := range s {
 		if !isValidIdentifierChar(s[i]) {
 			return false