Base: simplify UnitsSchemas management

Fixes: Maintaining schemas is difficult and error-prone

- Facilitate easy schemas add, remove, change, etc.
- Remove 14 files containing approx 2,190 lines of if/else code and data
- Place data in one file (UnitsSchemasData.h) using a normalized structure (including special functions)
- Isolate and simplify data operations (code)
- Remove schemas enum to keep data independent of code
- Separate responsibilities: Specifications, data, schemas, schema
- Add schema data 'isDefault'
- Add schema data name
- Prefer algorithms to raw loops
- Add schemas unit tests
- Tweak quantity unit tests

src/Base/UnitsSchemas.cpp

@@ -0,0 +1,145 @@
+/************************************************************************
+ *                                                                      *
+ *   This file is part of the FreeCAD CAx development system.           *
+ *                                                                      *
+ *   This library is free software; you can redistribute it and/or      *
+ *   modify it under the terms of the GNU Library General Public        *
+ *   License as published by the Free Software Foundation; either       *
+ *   version 2 of the License, or (at your option) any later version.   *
+ *                                                                      *
+ *   This library  is distributed in the hope that it will be useful,   *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of     *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the      *
+ *   GNU Library General Public License for more details.               *
+ *                                                                      *
+ *   You should have received a copy of the GNU Library General Public  *
+ *   License along with this library; see the file COPYING.LIB. If not, *
+ *   write to the Free Software Foundation, Inc., 59 Temple Place,      *
+ *   Suite 330, Boston, MA  02111-1307, USA                             *
+ *                                                                      *
+ ************************************************************************/
+
+#include <algorithm>
+#include <memory>
+#include <string>
+#include <vector>
+
+#include <QCoreApplication>
+
+#include "UnitsSchemas.h"
+#include "Exception.h"
+#include "Quantity.h"
+#include "UnitsApi.h"
+#include "UnitsSchema.h"
+#include "UnitsSchemasSpecs.h"
+#include "UnitsSchemasData.h"
+
+using Base::Quantity;
+using Base::UnitsSchema;
+using Base::UnitsSchemas;
+using Base::UnitsSchemaSpec;
+
+UnitsSchemas::UnitsSchemas(const UnitsSchemasDataPack& pack)
+    : pack {pack}
+    , denominator {pack.defDenominator}
+    , decimals {pack.defDecimals}
+{}
+
+size_t UnitsSchemas::count() const
+{
+    return pack.specs.size();
+}
+
+std::vector<std::string> UnitsSchemas::getVec(const std::function<std::string(UnitsSchemaSpec)>& fn)
+{
+    std::vector<std::string> vec;
+    std::transform(pack.specs.begin(), pack.specs.end(), std::back_inserter(vec), fn);
+
+    return vec;
+}
+
+std::vector<std::string> UnitsSchemas::names()
+{
+    return getVec([](const UnitsSchemaSpec& spec) {
+        return spec.name;
+    });
+}
+
+std::vector<std::string> UnitsSchemas::descriptions()
+{
+    return getVec([](const UnitsSchemaSpec& spec) {
+        return QCoreApplication::translate("UnitsApi", spec.description).toStdString();
+    });
+}
+
+std::size_t UnitsSchemas::getDecimals() const
+{
+    return pack.defDecimals;
+}
+
+std::size_t UnitsSchemas::defFractDenominator() const
+{
+    return pack.defDenominator;
+}
+
+void UnitsSchemas::setdefFractDenominator(const std::size_t size)
+{
+    denominator = size;
+}
+
+void UnitsSchemas::select()
+{
+    makeCurr(spec());
+}
+
+void UnitsSchemas::select(const std::string_view& name)
+{
+    makeCurr(spec(name));
+}
+
+void UnitsSchemas::select(const std::size_t num)
+{
+    makeCurr(spec(num));
+}
+
+UnitsSchema* UnitsSchemas::currentSchema() const
+{
+    return current.get();
+}
+
+void UnitsSchemas::makeCurr(const UnitsSchemaSpec& spec)
+{
+    current = std::make_unique<UnitsSchema>(spec);
+}
+
+UnitsSchemaSpec UnitsSchemas::findSpec(const std::function<bool(UnitsSchemaSpec)>& fn)
+{
+    const auto found = std::find_if(pack.specs.begin(), pack.specs.end(), fn);
+
+    if (found == pack.specs.end()) {
+        throw RuntimeError {"UnitSchemaSpec not found"};
+    }
+
+    return *found;
+}
+
+UnitsSchemaSpec UnitsSchemas::spec()
+{
+    return findSpec([](const UnitsSchemaSpec& spec) {
+        return spec.isDefault;
+    });
+}
+
+UnitsSchemaSpec UnitsSchemas::spec(const std::string_view& name)
+{
+    return findSpec([&name](const UnitsSchemaSpec& spec) {
+        return spec.name == name;
+    });
+}
+
+UnitsSchemaSpec UnitsSchemas::spec(const std::size_t num)
+{
+    return findSpec([&num](const UnitsSchemaSpec& spec) {
+        return spec.num == num;
+    });
+}