ESP8266WebServer - unused templated code throws out unused statics

currently, only w/ mock build because it is using gcc>=12

> ../../libraries/ESP8266WebServer/src/detail/RequestHandlersImpl.h:14:15: warning: ‘String esp8266webserver::calcETag(fs::FS&, const String&)’ defined but not used [-Wunused-function]
>   14 | static String calcETag(FS &fs, const String &path) {
>      |               ^~~~~~~~

Author: mcspr

libraries/ESP8266WebServer/src/detail/RequestHandlersImpl.h

@@ -9,25 +9,7 @@
 
 namespace esp8266webserver {
 
-// calculate an ETag for a file in filesystem based on md5 checksum
-// that can be used in the http headers - include quotes.
-static String calcETag(FS &fs, const String &path) {
-    String result;
-
-    // calculate eTag using md5 checksum
-    uint8_t md5_buf[16];
-    File f = fs.open(path, "r");
-    MD5Builder calcMD5;
-    calcMD5.begin();
-    calcMD5.addStream(f, f.size());
-    calcMD5.calculate();
-    calcMD5.getBytes(md5_buf);
-    f.close();
-    // create a minimal-length eTag using base64 byte[]->text encoding.
-    result = "\"" + base64::encode(md5_buf, 16, false) + "\"";
-    return(result);
-} // calcETag
-
+String calcETag(FS &, const String &);
 
 template<typename ServerType>
 class FunctionRequestHandler : public RequestHandler<ServerType> {
@@ -310,4 +292,4 @@ public StaticRequestHandler<ServerType> {
 
 } // namespace
 
-#endif //REQUESTHANDLERSIMPL_H
+#endif //REQUESTHANDLERSIMPL_H

libraries/ESP8266WebServer/src/detail/etag.cpp

@@ -0,0 +1,24 @@
+#include <ESP8266WebServer.h>
+
+namespace esp8266webserver {
+
+// calculate an ETag for a file in filesystem based on md5 checksum
+// that can be used in the http headers - include quotes.
+String calcETag(FS &fs, const String &path) {
+    String result;
+
+    // calculate eTag using md5 checksum
+    uint8_t md5_buf[16];
+    File f = fs.open(path, "r");
+    MD5Builder calcMD5;
+    calcMD5.begin();
+    calcMD5.addStream(f, f.size());
+    calcMD5.calculate();
+    calcMD5.getBytes(md5_buf);
+    f.close();
+    // create a minimal-length eTag using base64 byte[]->text encoding.
+    result = "\"" + base64::encode(md5_buf, 16, false) + "\"";
+    return(result);
+}
+
+} // namespace esp8266webserver