Pass std::string_view instead of const std::string&

* Starting with Actor::getBodyPartMesh and ending with
  Misc::StringUtils::ciEqual.
* Add tests for Misc::StringUtils::ciEqual.

apps/opencs/model/world/actoradapter.cpp

@@ -145,8 +145,7 @@ namespace CSMWorld
             return {};
         }
 
-        const std::string& partName = it->second.first;
-        return partName;
+        return it->second.first;
     }
 
     bool ActorAdapter::ActorData::hasDependency(const std::string& id) const

apps/opencs/model/world/collection.hpp

@@ -9,6 +9,7 @@
 #include <string>
 #include <functional>
 #include <memory>
+#include <string_view>
 
 #include <QVariant>
 
@@ -153,7 +154,7 @@ namespace CSMWorld
             ///< Change the state of a record from base to modified, if it is not already.
             ///  \return True if the record was changed.
 
-            int searchId (const std::string& id) const override;
+            int searchId(std::string_view id) const override;
             ////< Search record with \a id.
             /// \return index of record (if found) or -1 (not found)
 
@@ -476,7 +477,7 @@ namespace CSMWorld
     }
 
     template<typename ESXRecordT, typename IdAccessorT>
-    int Collection<ESXRecordT, IdAccessorT>::searchId (const std::string& id) const
+    int Collection<ESXRecordT, IdAccessorT>::searchId(std::string_view id) const
     {
         std::string id2 = Misc::StringUtils::lowerCase(id);
 

apps/opencs/model/world/collectionbase.hpp

@@ -4,6 +4,7 @@
 #include <string>
 #include <vector>
 #include <memory>
+#include <string_view>
 
 #include "universalid.hpp"
 #include "columns.hpp"
@@ -61,7 +62,7 @@ namespace CSMWorld
                 UniversalId::Type type = UniversalId::Type_None) = 0;
             ///< \param type Will be ignored, unless the collection supports multiple record types
 
-            virtual int searchId (const std::string& id) const = 0;
+            virtual int searchId(std::string_view id) const = 0;
             ////< Search record with \a id.
             /// \return index of record (if found) or -1 (not found)
 

apps/opencs/model/world/columns.cpp

@@ -391,7 +391,7 @@ int CSMWorld::Columns::getId (const std::string& name)
     std::string name2 = Misc::StringUtils::lowerCase (name);
 
     for (int i=0; sNames[i].mName; ++i)
-        if (Misc::StringUtils::ciEqual(sNames[i].mName, name2))
+        if (Misc::StringUtils::ciEqual(std::string_view(sNames[i].mName), name2))
             return sNames[i].mId;
 
     return -1;

apps/opencs/model/world/infocollection.cpp

@@ -97,7 +97,7 @@ void CSMWorld::InfoCollection::load (const Info& record, bool base)
     }
 }
 
-int CSMWorld::InfoCollection::getInfoIndex (const std::string& id, const std::string& topic) const
+int CSMWorld::InfoCollection::getInfoIndex(std::string_view id, std::string_view topic) const
 {
     // find the topic first
     std::unordered_map<std::string, std::vector<std::pair<std::string, int> > >::const_iterator iter
@@ -345,12 +345,12 @@ void  CSMWorld::InfoCollection::appendBlankRecord (const std::string& id, Univer
     insertRecord(std::move(record2), getInsertIndex(id, type, nullptr), type); // call InfoCollection::insertRecord()
 }
 
-int CSMWorld::InfoCollection::searchId (const std::string& id) const
+int CSMWorld::InfoCollection::searchId(std::string_view id) const
 {
     std::string::size_type separator = id.find_last_of('#');
 
     if (separator == std::string::npos)
-        throw std::runtime_error("invalid info ID: " + id);
+        throw std::runtime_error("invalid info ID: " + std::string(id));
 
     return getInfoIndex(id.substr(separator+1), id.substr(0, separator));
 }

apps/opencs/model/world/infocollection.hpp

@@ -2,6 +2,7 @@
 #define CSM_WOLRD_INFOCOLLECTION_H
 
 #include <unordered_map>
+#include <string_view>
 
 #include "collection.hpp"
 #include "info.hpp"
@@ -43,7 +44,7 @@ namespace CSMWorld
 
             void load (const Info& record, bool base);
 
-            int getInfoIndex (const std::string& id, const std::string& topic) const;
+            int getInfoIndex(std::string_view id, std::string_view topic) const;
             ///< Return index for record \a id or -1 (if not present; deleted records are considered)
             ///
             /// \param id info ID without topic prefix
@@ -79,7 +80,7 @@ namespace CSMWorld
             void appendBlankRecord (const std::string& id,
                                             UniversalId::Type type = UniversalId::Type_None) override;
 
-            int searchId (const std::string& id) const override;
+            int searchId(std::string_view id) const override;
 
             void appendRecord (std::unique_ptr<RecordBase> record,
                 UniversalId::Type type = UniversalId::Type_None) override;

apps/opencs/model/world/refcollection.cpp

@@ -7,6 +7,8 @@
 #include "universalid.hpp"
 #include "record.hpp"
 
+#include <string_view>
+
 namespace CSMWorld
 {
     template<>
@@ -261,7 +263,7 @@ void CSMWorld::RefCollection::cloneRecord (const std::string& origin,
    insertRecord(std::move(copy), getAppendIndex(destination, type)); // call RefCollection::insertRecord()
 }
 
-int CSMWorld::RefCollection::searchId (const std::string& id) const
+int CSMWorld::RefCollection::searchId(std::string_view id) const
 {
     return searchId(extractIdNum(id));
 }

apps/opencs/model/world/refcollection.hpp

@@ -2,6 +2,7 @@
 #define CSM_WOLRD_REFCOLLECTION_H
 
 #include <map>
+#include <string_view>
 
 #include "../doc/stage.hpp"
 
@@ -56,7 +57,7 @@ namespace CSMWorld
                                       const std::string& destination,
                                       const UniversalId::Type type);
 
-            virtual int searchId (const std::string& id) const;
+            virtual int searchId(std::string_view id) const;
 
             virtual void appendRecord (std::unique_ptr<RecordBase> record,
                                        UniversalId::Type type = UniversalId::Type_None);

apps/opencs/model/world/refidcollection.cpp

@@ -2,6 +2,7 @@
 
 #include <stdexcept>
 #include <memory>
+#include <string_view>
 
 #include <components/esm/esmreader.hpp>
 
@@ -787,7 +788,7 @@ void CSMWorld::RefIdCollection::appendBlankRecord (const std::string& id, Univer
     mData.appendRecord (type, id, false);
 }
 
-int CSMWorld::RefIdCollection::searchId (const std::string& id) const
+int CSMWorld::RefIdCollection::searchId(std::string_view id) const
 {
     RefIdData::LocalIndex localIndex = mData.searchId (id);
 

apps/opencs/model/world/refidcollection.hpp

@@ -4,6 +4,7 @@
 #include <vector>
 #include <map>
 #include <deque>
+#include <string_view>
 
 #include "columnbase.hpp"
 #include "collectionbase.hpp"
@@ -85,7 +86,7 @@ namespace CSMWorld
             void appendBlankRecord (const std::string& id, UniversalId::Type type) override;
             ///< \param type Will be ignored, unless the collection supports multiple record types
 
-            int searchId (const std::string& id) const override;
+            int searchId(std::string_view id) const override;
             ////< Search record with \a id.
             /// \return index of record (if found) or -1 (not found)
 

apps/opencs/model/world/refiddata.cpp

@@ -2,6 +2,7 @@
 
 #include <cassert>
 #include <memory>
+#include <string_view>
 
 CSMWorld::RefIdDataContainerBase::~RefIdDataContainerBase() {}
 
@@ -74,8 +75,7 @@ int CSMWorld::RefIdData::localToGlobalIndex (const LocalIndex& index)
     return globalIndex;
 }
 
-CSMWorld::RefIdData::LocalIndex CSMWorld::RefIdData::searchId (
-    const std::string& id) const
+CSMWorld::RefIdData::LocalIndex CSMWorld::RefIdData::searchId(std::string_view id) const
 {
     std::string id2 = Misc::StringUtils::lowerCase (id);
 

apps/opencs/model/world/refiddata.hpp

@@ -5,6 +5,7 @@
 #include <map>
 #include <memory>
 #include <cassert>
+#include <string_view>
 
 #include <components/esm/loadacti.hpp>
 #include <components/esm/loadalch.hpp>
@@ -277,7 +278,7 @@ namespace CSMWorld
 
             int localToGlobalIndex (const LocalIndex& index) const;
 
-            LocalIndex searchId (const std::string& id) const;
+            LocalIndex searchId(std::string_view id) const;
 
             void erase (int index, int count);
 

apps/opencs/model/world/resources.cpp

@@ -3,6 +3,7 @@
 #include <sstream>
 #include <stdexcept>
 #include <algorithm>
+#include <string_view>
 
 #include <components/vfs/manager.hpp>
 
@@ -83,7 +84,7 @@ int CSMWorld::Resources::getIndex (const std::string& id) const
     return index;
 }
 
-int CSMWorld::Resources::searchId (const std::string& id) const
+int CSMWorld::Resources::searchId(std::string_view id) const
 {
     std::string id2 = Misc::StringUtils::lowerCase (id);
 

apps/opencs/model/world/resources.hpp

@@ -4,6 +4,7 @@
 #include <string>
 #include <map>
 #include <vector>
+#include <string_view>
 
 #include "universalid.hpp"
 
@@ -35,7 +36,7 @@ namespace CSMWorld
 
             int getIndex (const std::string& id) const;
 
-            int searchId (const std::string& id) const;
+            int searchId(std::string_view id) const;
 
             UniversalId::Type getType() const;
     };

apps/opencs/view/render/actor.cpp

@@ -96,7 +96,7 @@ namespace CSVRender
         for (int i = 0; i < ESM::PRT_Count; ++i)
         {
             auto type = (ESM::PartReferenceType) i;
-            const std::string partId(mActorData->getPart(type));
+            const std::string_view partId = mActorData->getPart(type);
             attachBodyPart(type, getBodyPartMesh(partId));
         }
     }
@@ -115,7 +115,7 @@ namespace CSVRender
         }
     }
 
-    std::string Actor::getBodyPartMesh(const std::string& bodyPartId)
+    std::string Actor::getBodyPartMesh(std::string_view bodyPartId)
     {
         const auto& bodyParts = mData.getBodyParts();
 

apps/opencs/view/render/actor.hpp

@@ -2,6 +2,7 @@
 #define OPENCS_VIEW_RENDER_ACTOR_H
 
 #include <string>
+#include <string_view>
 
 #include <osg/ref_ptr>
 
@@ -54,7 +55,7 @@ namespace CSVRender
         void loadBodyParts();
         void attachBodyPart(ESM::PartReferenceType, const std::string& mesh);
 
-        std::string getBodyPartMesh(const std::string& bodyPartId);
+        std::string getBodyPartMesh(std::string_view bodyPartId);
 
         static const std::string MeshPrefix;
 

apps/openmw/mwgui/messagebox.cpp

@@ -376,7 +376,9 @@ namespace MWGui
         {
             for (const std::string& keyword : keywords)
             {
-                if(Misc::StringUtils::ciEqual(MyGUI::LanguageManager::getInstance().replaceTags("#{" + keyword + "}"), button->getCaption()))
+                if (Misc::StringUtils::ciEqual(
+                        MyGUI::LanguageManager::getInstance().replaceTags("#{" + keyword + "}").asUTF8(),
+                        button->getCaption().asUTF8()))
                 {
                     return button;
                 }

apps/openmw_test_suite/misc/test_stringops.cpp

@@ -1,6 +1,10 @@
 #include <gtest/gtest.h>
 #include "components/misc/stringops.hpp"
 
+#include <string>
+#include <string_view>
+#include <type_traits>
+
 struct PartialBinarySearchTest : public ::testing::Test
 {
   protected:
@@ -12,10 +16,6 @@ struct PartialBinarySearchTest : public ::testing::Test
         std::sort(mDataVec.begin(), mDataVec.end(), Misc::StringUtils::ciLess);
     }
 
-    void TearDown() override
-    {
-    }
-
     bool matches(const std::string& keyword)
     {
         return Misc::StringUtils::partialBinarySearch(mDataVec.begin(), mDataVec.end(), keyword) != mDataVec.end();
@@ -51,3 +51,97 @@ TEST_F (PartialBinarySearchTest, ci_test)
     std::string unicode1 = "\u04151 \u0418"; // CYRILLIC CAPITAL LETTER IE, CYRILLIC CAPITAL LETTER I
     EXPECT_TRUE( Misc::StringUtils::lowerCase(unicode1) == unicode1 );
 }
+
+namespace
+{
+    using ::Misc::StringUtils;
+    using namespace ::testing;
+
+    template <class T>
+    struct MiscStringUtilsCiEqualEmptyTest : Test {};
+
+    TYPED_TEST_SUITE_P(MiscStringUtilsCiEqualEmptyTest);
+
+    TYPED_TEST_P(MiscStringUtilsCiEqualEmptyTest, empty_strings_should_be_equal)
+    {
+        EXPECT_TRUE(StringUtils::ciEqual(typename TypeParam::first_type {}, typename TypeParam::second_type {}));
+    }
+
+    REGISTER_TYPED_TEST_SUITE_P(MiscStringUtilsCiEqualEmptyTest,
+        empty_strings_should_be_equal
+    );
+
+    using EmptyStringTypePairsTypes = Types<
+        std::pair<std::string, std::string>,
+        std::pair<std::string, std::string_view>,
+        std::pair<std::string, const char[1]>,
+        std::pair<std::string_view, std::string>,
+        std::pair<std::string_view, std::string_view>,
+        std::pair<std::string_view, const char[1]>,
+        std::pair<const char[1], std::string>,
+        std::pair<const char[1], std::string_view>,
+        std::pair<const char[1], const char[1]>
+    >;
+
+    INSTANTIATE_TYPED_TEST_SUITE_P(EmptyStringTypePairs, MiscStringUtilsCiEqualEmptyTest, EmptyStringTypePairsTypes);
+
+    template <class T>
+    struct MiscStringUtilsCiEqualNotEmptyTest : Test {};
+
+    TYPED_TEST_SUITE_P(MiscStringUtilsCiEqualNotEmptyTest);
+
+    using RawValue = const char[4];
+
+    constexpr RawValue foo = "foo";
+    constexpr RawValue fooUpper = "FOO";
+    constexpr RawValue bar = "bar";
+
+    template <typename T>
+    using Value = std::conditional_t<std::is_same_v<T, RawValue>, RawValue&, T>;
+
+    TYPED_TEST_P(MiscStringUtilsCiEqualNotEmptyTest, same_strings_should_be_equal)
+    {
+        const Value<typename TypeParam::first_type> a {foo};
+        const Value<typename TypeParam::second_type> b {foo};
+        EXPECT_TRUE(StringUtils::ciEqual(a, b)) << a << "\n" << b;
+    }
+
+    TYPED_TEST_P(MiscStringUtilsCiEqualNotEmptyTest, same_strings_with_different_case_sensetivity_should_be_equal)
+    {
+        const Value<typename TypeParam::first_type> a {foo};
+        const Value<typename TypeParam::second_type> b {fooUpper};
+        EXPECT_TRUE(StringUtils::ciEqual(a, b)) << a << "\n" << b;
+    }
+
+    TYPED_TEST_P(MiscStringUtilsCiEqualNotEmptyTest, different_strings_content_should_not_be_equal)
+    {
+        const Value<typename TypeParam::first_type> a {foo};
+        const Value<typename TypeParam::second_type> b {bar};
+        EXPECT_FALSE(StringUtils::ciEqual(a, b)) << a << "\n" << b;
+    }
+
+    REGISTER_TYPED_TEST_SUITE_P(MiscStringUtilsCiEqualNotEmptyTest,
+        same_strings_should_be_equal,
+        same_strings_with_different_case_sensetivity_should_be_equal,
+        different_strings_content_should_not_be_equal
+    );
+
+    using NotEmptyStringTypePairsTypes = Types<
+        std::pair<std::string, std::string>,
+        std::pair<std::string, std::string_view>,
+        std::pair<std::string, const char[4]>,
+        std::pair<std::string_view, std::string>,
+        std::pair<std::string_view, std::string_view>,
+        std::pair<std::string_view, const char[4]>,
+        std::pair<const char[4], std::string>,
+        std::pair<const char[4], std::string_view>,
+        std::pair<const char[4], const char[4]>
+    >;
+
+    INSTANTIATE_TYPED_TEST_SUITE_P(NotEmptyStringTypePairs, MiscStringUtilsCiEqualNotEmptyTest, NotEmptyStringTypePairsTypes);
+
+    TEST(MiscStringUtilsCiEqualTest, string_with_different_length_should_not_be_equal)
+    {
+        EXPECT_FALSE(StringUtils::ciEqual(std::string("a"), std::string("aa")));
+    }
+}

components/misc/stringops.hpp

@@ -4,6 +4,8 @@
 #include <cctype>
 #include <string>
 #include <algorithm>
+#include <string_view>
+#include <iterator>
 
 #include "utf8stream.hpp"
 
@@ -109,18 +111,34 @@ public:
         return std::lexicographical_compare(x.begin(), x.end(), y.begin(), y.end(), ci());
     }
 
-    static bool ciEqual(const std::string &x, const std::string &y) {
-        if (x.size() != y.size()) {
+    template <class X, class Y>
+    static bool ciEqual(const X& x, const Y& y)
+    {
+        if (std::size(x) != std::size(y))
             return false;
-        }
-        std::string::const_iterator xit = x.begin();
-        std::string::const_iterator yit = y.begin();
-        for (; xit != x.end(); ++xit, ++yit) {
-            if (toLower(*xit) != toLower(*yit)) {
-                return false;
-            }
-        }
-        return true;
+        return std::equal(std::begin(x), std::end(x), std::begin(y),
+                          [] (char l, char r) { return toLower(l) == toLower(r); });
+    }
+
+    template <std::size_t n>
+    static auto ciEqual(const char(& x)[n], const char(& y)[n])
+    {
+        static_assert(n > 0);
+        return ciEqual(std::string_view(x, n - 1), std::string_view(y, n - 1));
+    }
+
+    template <std::size_t n, class T>
+    static auto ciEqual(const char(& x)[n], const T& y)
+    {
+        static_assert(n > 0);
+        return ciEqual(std::string_view(x, n - 1), y);
+    }
+
+    template <std::size_t n, class T>
+    static auto ciEqual(const T& x, const char(& y)[n])
+    {
+        static_assert(n > 0);
+        return ciEqual(x, std::string_view(y, n - 1));
     }
 
     static int ciCompareLen(const std::string &x, const std::string &y, size_t len)
@@ -157,9 +175,9 @@ public:
     }
 
     /// Returns lower case copy of input string
-    static std::string lowerCase(const std::string &in)
+    static std::string lowerCase(std::string_view in)
     {
-        std::string out = in;
+        std::string out(in);
         lowerCaseInPlace(out);
         return out;
     }

components/sceneutil/visitor.cpp

@@ -9,6 +9,9 @@
 
 #include <components/misc/stringops.hpp>
 
+#include <cstring>
+#include <string_view>
+
 namespace SceneUtil
 {
 
@@ -24,7 +27,7 @@ namespace SceneUtil
 
     void FindByClassVisitor::apply(osg::Node &node)
     {
-        if (Misc::StringUtils::ciEqual(node.className(), mNameToFind))
+        if (Misc::StringUtils::ciEqual(std::string_view(node.className()), mNameToFind))
             mFoundNodes.push_back(&node);
 
         traverse(node);