util: Move TrimString(...). Introduce default pattern (trims whitespace). Add NODISCARD.

src/util/string.h

@@ -11,6 +11,16 @@
 #include <string>
 #include <vector>
 
+NODISCARD inline std::string TrimString(const std::string& str, const std::string& pattern = " \f\n\r\t\v")
+{
+    std::string::size_type front = str.find_first_not_of(pattern);
+    if (front == std::string::npos) {
+        return std::string();
+    }
+    std::string::size_type end = str.find_last_not_of(pattern);
+    return str.substr(front, end - front + 1);
+}
+
 /**
  * Join a list of items
  *

src/util/system.cpp

@@ -7,6 +7,7 @@
 
 #include <chainparamsbase.h>
 #include <util/strencodings.h>
+#include <util/string.h>
 #include <util/translation.h>
 
 
@@ -679,16 +680,6 @@ fs::path GetConfigFile(const std::string& confPath)
     return AbsPathForConfigVal(fs::path(confPath), false);
 }
 
-static std::string TrimString(const std::string& str, const std::string& pattern)
-{
-    std::string::size_type front = str.find_first_not_of(pattern);
-    if (front == std::string::npos) {
-        return std::string();
-    }
-    std::string::size_type end = str.find_last_not_of(pattern);
-    return str.substr(front, end - front + 1);
-}
-
 static bool GetConfigOptions(std::istream& stream, const std::string& filepath, std::string& error, std::vector<std::pair<std::string, std::string>>& options, std::list<SectionInfo>& sections)
 {
     std::string str, prefix;