1 files changed, 35 insertions, 0 deletions
diff --git a/Source/Core/Common/FormatUtil.h b/Source/Core/Common/FormatUtil.h
index 3c0bc3f262..1b33b74256 100644
--- a/Source/Core/Common/FormatUtil.h
+++ b/Source/Core/Common/FormatUtil.h
@@ -38,4 +38,39 @@ constexpr std::size_t CountFmtReplacementFields(std::string_view s)
 static_assert(CountFmtReplacementFields("") == 0);
 static_assert(CountFmtReplacementFields("{} test {:x}") == 2);
 static_assert(CountFmtReplacementFields("{} {{}} test {{{}}}") == 2);
+
+constexpr bool ContainsNonPositionalArguments(std::string_view s)
+{
+  for (std::size_t i = 0; i < s.size(); ++i)
+  {
+    if (s[i] != '{' || i + 1 == s.size())
+      continue;
+
+    const char next = s[i + 1];
+
+    // If the opening brace is followed by another brace, what we have is
+    // an escaped brace, not a replacement field.
+    if (next == '{')
+    {
+      // Skip the second brace.
+      // This ensures that e.g. {{{}}} is counted correctly: when the first brace character
+      // is read and detected as being part of an '{{' escape sequence, the second character
+      // is skipped so the most inner brace (the third character) is not detected
+      // as the end of an '{{' pair.
+      ++i;
+    }
+    else if (next == '}' || next == ':')
+    {
+      return true;
+    }
+  }
+  return false;
+}
+
+static_assert(!ContainsNonPositionalArguments(""));
+static_assert(ContainsNonPositionalArguments("{}"));
+static_assert(!ContainsNonPositionalArguments("{0}"));
+static_assert(ContainsNonPositionalArguments("{:x}"));
+static_assert(!ContainsNonPositionalArguments("{0:x}"));
+static_assert(!ContainsNonPositionalArguments("{0} {{}} test {{{1}}}"));
 }  // namespace Common