options: Add all type support for vector parsing (#1597)

options: Add int and string vector parsing support

library/private/options_tools.h.in

@@ -10,14 +10,45 @@ namespace f3d
 {
 namespace options_tools
 {
-// TODO expose parse methods in options API ?
 
 //----------------------------------------------------------------------------
 /**
- * Not implemented generic templated parse method
+ * A std::string_view trim function
  */
+std::string trim(std::string_view strv)
+{
+  constexpr std::string_view spaces = " \t\r\v\n";
+  strv.remove_prefix(std::min(strv.find_first_not_of(spaces), strv.size()));
+  strv.remove_suffix(std::min(strv.size() - strv.find_last_not_of(spaces) - 1, strv.size()));
+  return std::string(strv);
+}
+
+//----------------------------------------------------------------------------
+/**
+ * Vector specific templated parse method
+ */
+template<typename T>
+struct is_vector : std::false_type
+{
+};
+template<typename... Args>
+struct is_vector<std::vector<Args...>> : std::true_type
+{
+};
 template<typename T>
-T parse(const std::string& str) = delete;
+T parse(const std::string& str)
+{
+  static_assert(is_vector<T>::value, "non-vector types parsing must be specialized");
+
+  // TODO implement more parsing possibilities, eg different types of tokens
+  T vec;
+  std::istringstream split(str);
+  for (std::string each; std::getline(split, each, ',');)
+  {
+    vec.emplace_back(options_tools::parse<typename T::value_type>(each));
+  }
+  return vec;
+}
 
 //----------------------------------------------------------------------------
 /**
@@ -100,31 +131,12 @@ ratio_t parse(const std::string& str)
 
 //----------------------------------------------------------------------------
 /**
- * Return provided string
+ * Return provided string stripped of leading and trailing spaces.
  */
 template<>
 std::string parse(const std::string& str)
 {
-  return str;
-}
-
-//----------------------------------------------------------------------------
-/**
- * Parse provided string into a double vector
- * Split the string using ',', then rely on double version for parsing each token
- * Can throw options::parsing_exception in case of failure to parse
- */
-template<>
-std::vector<double> parse(const std::string& str)
-{
-  // TODO implement more parsing possibilities, eg different types of tokens
-  std::vector<double> vec;
-  std::istringstream split(str);
-  for (std::string each; std::getline(split, each, ',');)
-  {
-    vec.emplace_back(options_tools::parse<double>(each));
-  }
-  return vec;
+  return options_tools::trim(str);
 }
 
 // TODO Improve string generation

library/public/options.h.in

@@ -108,7 +108,9 @@ public:
 
   /**
    * Templated parsing method used internally to parse strings.
-   * Implemented only for: bool, int, double, ratio_t, string and double vector.
+   * Implemented only for types: bool, int, double, ratio_t,
+   * as well as vector for each of these types.
+   * See parsing documentation for more info. TODO.
    * Throw an options::parsing_exception if parsing failed.
    */
   template<typename T>

library/src/options.cxx

@@ -113,13 +113,16 @@ T options::parse(const std::string& str)
 }
 
 //----------------------------------------------------------------------------
-#define F3D_DECL_TYPE(TYPE) template F3D_EXPORT TYPE options::parse<TYPE>(const std::string& str)
+#define F3D_DECL_TYPE_INTERNAL(TYPE)                                                               \
+  template F3D_EXPORT TYPE options::parse<TYPE>(const std::string& str)
+#define F3D_DECL_TYPE(TYPE)                                                                        \
+  F3D_DECL_TYPE_INTERNAL(TYPE);                                                                    \
+  F3D_DECL_TYPE_INTERNAL(std::vector<TYPE>)
 F3D_DECL_TYPE(bool);
 F3D_DECL_TYPE(int);
 F3D_DECL_TYPE(double);
 F3D_DECL_TYPE(f3d::ratio_t);
 F3D_DECL_TYPE(std::string);
-F3D_DECL_TYPE(std::vector<double>);
 
 //----------------------------------------------------------------------------
 options::parsing_exception::parsing_exception(const std::string& what)

library/testing/TestSDKOptions.cxx

@@ -312,17 +312,29 @@ int TestSDKOptions(int argc, char* argv[])
     std::cerr << "Options parse method not behaving as expected with ratio_t." << std::endl;
     return EXIT_FAILURE;
   }
-  if (f3d::options::parse<std::string>(std::string("foobar")) != "foobar")
+  if (f3d::options::parse<std::string>(std::string("  foobar  ")) != "foobar")
   {
     std::cerr << "Options parse method not behaving as expected with string." << std::endl;
     return EXIT_FAILURE;
   }
+  if (f3d::options::parse<std::vector<int>>(std::string("1, 2, 3")) !=
+    std::vector<int>({ 1, 2, 3 }))
+  {
+    std::cerr << "Options parse method not behaving as expected with int vector." << std::endl;
+    return EXIT_FAILURE;
+  }
   if (f3d::options::parse<std::vector<double>>(std::string("0.1, 0.2, 0.3")) !=
     std::vector<double>({ 0.1, 0.2, 0.3 }))
   {
     std::cerr << "Options parse method not behaving as expected with double vector." << std::endl;
     return EXIT_FAILURE;
   }
+  if (f3d::options::parse<std::vector<std::string>>(std::string("foo, bar, baz")) !=
+    std::vector<std::string>({ "foo", "bar", "baz" }))
+  {
+    std::cerr << "Options parse method not behaving as expected with string vector." << std::endl;
+    return EXIT_FAILURE;
+  }
 
   return EXIT_SUCCESS;
 }