chore: import upstream snapshot with attribution

internal/resolver/cpp_stdlib_headers_test.go

@@ -0,0 +1,25 @@
+package resolver
+
+import "testing"
+
+func TestIsCppStdlibHeader(t *testing.T) {
+	stdlib := []string{
+		"stdio.h", "stdlib.h", "string.h", "stdatomic.h", // C
+		"vector", "memory", "string", "unordered_map", "filesystem", // C++
+		"cstdio", "cstring", "cstdint", // <cXXX> wrappers
+		"unistd.h", "pthread.h", "sys/types.h", "arpa/inet.h", // POSIX
+	}
+	for _, h := range stdlib {
+		if !IsCppStdlibHeader(h) {
+			t.Errorf("IsCppStdlibHeader(%q) = false, want true", h)
+		}
+	}
+	notStdlib := []string{
+		"", "proj/api.h", "myheader.h", "vector.h", "foo", "config.h", "string_view.h",
+	}
+	for _, h := range notStdlib {
+		if IsCppStdlibHeader(h) {
+			t.Errorf("IsCppStdlibHeader(%q) = true, want false", h)
+		}
+	}
+}