Implement '~' operator

Author: flexferrum

src/expression_evaluator.cpp

@@ -92,6 +92,25 @@ InternalValue BinaryExpression::Evaluate(RenderContext& context)
         break;
     }
     case jinja2::BinaryExpression::StringConcat:
+    {
+        auto leftStr = context.GetRendererCallback()->GetAsTargetString(leftVal);
+        auto rightStr = context.GetRendererCallback()->GetAsTargetString(rightVal);
+        TargetString resultStr;
+        std::string* nleftStr = boost::get<std::string>(&leftStr);
+        if (nleftStr != nullptr)
+        {
+            auto* nrightStr = boost::get<std::string>(&rightStr);
+            resultStr = *nleftStr + *nrightStr;
+        }
+        else
+        {
+            auto* wleftStr = boost::get<std::wstring>(&leftStr);
+            auto* wrightStr = boost::get<std::wstring>(&rightStr);
+            resultStr = *wleftStr + *wrightStr;
+        }
+        result = InternalValue(std::move(resultStr));
+        break;
+    }
     default:
         break;
     }

src/render_context.h

@@ -7,10 +7,16 @@
 
 namespace jinja2
 {
+struct IRendererCallback
+{
+    virtual TargetString GetAsTargetString(const InternalValue& val) = 0;
+};
+
 class RenderContext
 {
 public:
-    RenderContext(const InternalValueMap& extValues)
+    RenderContext(const InternalValueMap& extValues, IRendererCallback* rendererCallback)
+        : m_rendererCallback(rendererCallback)
     {
         m_externalScope = &extValues;
         EnterScope();
@@ -63,10 +69,15 @@ class RenderContext
     {
         return *m_currentScope;
     }
+    auto GetRendererCallback()
+    {
+        return m_rendererCallback;
+    }
 private:
     InternalValueMap* m_currentScope;
     const InternalValueMap* m_externalScope;
     std::list<InternalValueMap> m_scopes;
+    IRendererCallback* m_rendererCallback;
 
 };
 } // jinja2

src/template_impl.h

@@ -55,7 +55,8 @@ class TemplateImpl : public ITemplateImpl
                 else
                     intParams[ip.first] = newParam.get();
             }
-            RenderContext context(intParams);
+            RendererCallback<CharT> callback;
+            RenderContext context(intParams, &callback);
             OutStream outStream(
             [this, &os](size_t offset, size_t length) {
                 os.write(m_template.data() + offset, length);
@@ -68,6 +69,18 @@ class TemplateImpl : public ITemplateImpl
         }
     }
 
+    template<typename CharT>
+    class RendererCallback : public IRendererCallback
+    {
+    public:
+        TargetString GetAsTargetString(const InternalValue& val) override
+        {
+            std::basic_ostringstream<CharT> os;
+            Apply<visitors::ValueRenderer<CharT>>(val, os);
+            return TargetString(os.str());
+        }
+    };
+
 private:
 
     std::basic_string<CharT> m_template;

src/value_visitors.h

@@ -96,64 +96,6 @@ struct BaseVisitor : public boost::static_visitor<R>
     {
         return R();
     }
-#if 0
-    template<typename U>
-    R operator() (const GenericMap&, U&&) const
-    {
-        assert(false);
-        return R();
-    }
-
-    template<typename U>
-    R operator() (const GenericList&, U&&) const
-    {
-        assert(false);
-        return R();
-    }
-
-    template<typename U>
-    R operator() (const ValueRef&, U&&) const
-    {
-        assert(false);
-        return R();
-    }
-
-    template<typename U>
-    R operator() (const TargetString&, U&&) const
-    {
-        assert(false);
-        return R();
-    }
-
-    template<typename T>
-    R operator() (T&&, const GenericMap&) const
-    {
-        assert(false);
-        return R();
-    }
-
-    template<typename T>
-    R operator() (T&&, const GenericList&) const
-    {
-        assert(false);
-        return R();
-    }
-
-    template<typename T>
-    R operator() (T&&, const ValueRef&) const
-    {
-        assert(false);
-        return R();
-    }
-
-    template<typename T>
-    R operator() (T&&, const TargetString&) const
-    {
-        assert(false);
-        return R();
-    }
-#endif
-
 };
 
 

test/expressions_test.cpp

@@ -23,6 +23,7 @@ TEST(ExpressionsTest, BinaryMathOperations)
 {{ 10 ** -2 }}
 {{ 10/10 + 2*5 }}
 {{ 'Hello' + " " + 'World ' + stringValue }}
+{{ 'Hello' ~ " " ~ 123 ~ ' ' ~ 1.234 ~ " " ~ true ~ " " ~ intValue ~ " " ~ false ~ ' ' ~ 'World ' ~ stringValue }}
 )";
 
     Template tpl;
@@ -51,6 +52,7 @@ TEST(ExpressionsTest, BinaryMathOperations)
 0.01
 11
 Hello World rain
+Hello 123 1.234 true 3 false World rain
 )";
 
     EXPECT_STREQ(expectedResult.c_str(), result.c_str());