Add constructor to support cstring_view construction from a null-terminated C string and its length (avoids duplicate strlen call)

Author: ArnavT005

include/tuli/cstring_view.hpp

@@ -23,6 +23,12 @@ class cstring_view {
                "tuli::cstring_view cannot be constructed from nullptr");
     }
 
+    constexpr cstring_view(null_terminated_t, const char* s, std::size_t len)
+        : m_sv{s, len} {
+        assert(m_sv.data() != nullptr &&
+               "tuli::cstring_view cannot be constructed from nullptr");
+    }
+
     constexpr cstring_view(null_terminated_t, std::string_view sv) noexcept
         : m_sv{sv.data() ? sv : ""} {}
 

tests/cstring_view.cpp

@@ -30,6 +30,17 @@ TEST(CStringViewTest, FromCString) {
     static_assert(csv == std::string_view{s});
 }
 
+TEST(CStringViewTest, FromNullTerminatedCStringAndLen) {
+    constexpr auto s{"Hello, World!"};
+    constexpr auto len{tests::strlen(s)};
+    constexpr tuli::cstring_view csv{tuli::null_terminated, s, len};
+
+    static_assert(csv.length() == len);
+    static_assert(!csv.is_empty());
+    static_assert(tests::strcmp(csv.c_str(), s));
+    static_assert(csv == std::string_view{s});
+}
+
 TEST(CStringViewTest, FromNullTerminatedStringView) {
     constexpr auto sv{"Hello, World!"sv};
     constexpr tuli::cstring_view csv{tuli::null_terminated, sv};