cmSystemTools: Remove IsInternallyOn, IsNOTFOUND, IsOn, IsOff

The removes the following methods from cmSystemTools:

- `IsInternallyOn`
- `IsNOTFOUND`
- `IsOn`
- `IsOff`

Source/cmSystemTools.cxx

@@ -250,85 +250,6 @@ void cmSystemTools::ReportLastSystemError(const char* msg)
   cmSystemTools::Error(m);
 }
 
-bool cmSystemTools::IsInternallyOn(cm::string_view val)
-{
-  return (val.size() == 4) &&           //
-    (val[0] == 'I' || val[0] == 'i') && //
-    (val[1] == '_') &&                  //
-    (val[2] == 'O' || val[2] == 'o') && //
-    (val[3] == 'N' || val[3] == 'n');
-}
-
-bool cmSystemTools::IsOn(cm::string_view val)
-{
-  switch (val.size()) {
-    case 1:
-      return val[0] == '1' || val[0] == 'Y' || val[0] == 'y';
-    case 2:
-      return                                //
-        (val[0] == 'O' || val[0] == 'o') && //
-        (val[1] == 'N' || val[1] == 'n');
-    case 3:
-      return                                //
-        (val[0] == 'Y' || val[0] == 'y') && //
-        (val[1] == 'E' || val[1] == 'e') && //
-        (val[2] == 'S' || val[2] == 's');
-    case 4:
-      return                                //
-        (val[0] == 'T' || val[0] == 't') && //
-        (val[1] == 'R' || val[1] == 'r') && //
-        (val[2] == 'U' || val[2] == 'u') && //
-        (val[3] == 'E' || val[3] == 'e');
-    default:
-      break;
-  }
-
-  return false;
-}
-
-bool cmSystemTools::IsNOTFOUND(cm::string_view val)
-{
-  return (val == "NOTFOUND") || cmHasLiteralSuffix(val, "-NOTFOUND");
-}
-
-bool cmSystemTools::IsOff(cm::string_view val)
-{
-  switch (val.size()) {
-    case 0:
-      return true;
-    case 1:
-      return val[0] == '0' || val[0] == 'N' || val[0] == 'n';
-    case 2:
-      return                                //
-        (val[0] == 'N' || val[0] == 'n') && //
-        (val[1] == 'O' || val[1] == 'o');
-    case 3:
-      return                                //
-        (val[0] == 'O' || val[0] == 'o') && //
-        (val[1] == 'F' || val[1] == 'f') && //
-        (val[2] == 'F' || val[2] == 'f');
-    case 5:
-      return                                //
-        (val[0] == 'F' || val[0] == 'f') && //
-        (val[1] == 'A' || val[1] == 'a') && //
-        (val[2] == 'L' || val[2] == 'l') && //
-        (val[3] == 'S' || val[3] == 's') && //
-        (val[4] == 'E' || val[4] == 'e');
-    case 6:
-      return                                //
-        (val[0] == 'I' || val[0] == 'i') && //
-        (val[1] == 'G' || val[1] == 'g') && //
-        (val[2] == 'N' || val[2] == 'n') && //
-        (val[3] == 'O' || val[3] == 'o') && //
-        (val[4] == 'R' || val[4] == 'r') && //
-        (val[5] == 'E' || val[5] == 'e');
-    default:
-      break;
-  }
-
-  return cmSystemTools::IsNOTFOUND(val);
-}
-
 void cmSystemTools::ParseWindowsCommandLine(const char* command,
                                             std::vector<std::string>& args)
 {

Source/cmSystemTools.h

@@ -94,50 +94,6 @@ public:
     cmSystemTools::s_ErrorOccured = false;
   }
 
-  /**
-   * Does a string indicates that CMake/CPack/CTest internally
-   * forced this value. This is not the same as On, but this
-   * may be considered as "internally switched on".
-   */
-  static bool IsInternallyOn(cm::string_view val);
-  static inline bool IsInternallyOn(const char* val)
-  {
-    if (!val) {
-      return false;
-    }
-    return IsInternallyOn(cm::string_view(val));
-  }
-
-  /**
-   * Does a string indicate a true or on value? This is not the same as ifdef.
-   */
-  static bool IsOn(cm::string_view val);
-  inline static bool IsOn(const char* val)
-  {
-    if (!val) {
-      return false;
-    }
-    return IsOn(cm::string_view(val));
-  }
-
-  /**
-   * Does a string indicate a false or off value ? Note that this is
-   * not the same as !IsOn(...) because there are a number of
-   * ambiguous values such as "/usr/local/bin" a path will result in
-   * IsON and IsOff both returning false. Note that the special path
-   * NOTFOUND, *-NOTFOUND or IGNORE will cause IsOff to return true.
-   */
-  static bool IsOff(cm::string_view val);
-  inline static bool IsOff(const char* val)
-  {
-    if (!val) {
-      return true;
-    }
-    return IsOff(cm::string_view(val));
-  }
-
-  //! Return true if value is NOTFOUND or ends in -NOTFOUND.
-  static bool IsNOTFOUND(cm::string_view val);
   //! Return true if the path is a framework
   static bool IsPathToFramework(const std::string& value);