fix: improve error message formatting and add test for unknown parameter type

Author: daantimmer

cucumber_cpp/library/cucumber_expression/Errors.cpp

@@ -20,8 +20,7 @@ namespace cucumber_cpp::library::cucumber_expression
         auto pointer = PointAt(node.Start());
         if (node.Start() + 1 < node.End())
         {
-            for (auto i = node.Start() + 1; i < node.End(); ++i)
-                pointer += "-";
+            pointer.resize(node.End() - 1, '-');
             pointer += "^";
         }
         return pointer;
@@ -161,8 +160,8 @@ For more complicated expressions consider using a regular expression instead.)",
             node.Start(),
             expression,
             PointAtLocated(node),
-            std::format(R"('Undefined parameter type {}')", undefinedParameterName),
-            std::format(R"('Please register a ParameterType for {}')", undefinedParameterName),
+            std::format(R"(Undefined parameter type '{}')", undefinedParameterName),
+            std::format(R"(Please register a ParameterType for '{}')", undefinedParameterName),
         }
     {}
 }

cucumber_cpp/library/cucumber_expression/test/TestExpression.cpp

@@ -1,4 +1,5 @@
 
+#include "cucumber_cpp/library/cucumber_expression/Errors.hpp"
 #include "cucumber_cpp/library/cucumber_expression/Expression.hpp"
 #include "cucumber_cpp/library/cucumber_expression/ParameterRegistry.hpp"
 #include "yaml-cpp/node/node.h"
@@ -200,4 +201,24 @@ namespace cucumber_cpp::library::cucumber_expression
         EXPECT_THAT(std::any_cast<bool>((*Match(R"__({bool})__", R"__(off)__"))[0]), testing::IsFalse());
         EXPECT_THAT(std::any_cast<bool>((*Match(R"__({bool})__", R"__(foo)__"))[0]), testing::IsFalse());
     }
+
+    TEST_F(TestExpression, ThrowUnknownParameterType)
+    {
+        auto expr = "I have {doesnotexist} cuke(s)";
+
+        try
+        {
+            Expression expression{ expr, parameterRegistry };
+            FAIL() << "Expected UndefinedParameterTypeError to be thrown";
+        }
+        catch (UndefinedParameterTypeError e)
+        {
+            EXPECT_THAT(e.what(), testing::StrEq("This Cucumber Expression has a problem at column 8:\n"
+                                                 "\n"
+                                                 "I have {doesnotexist} cuke(s)\n"
+                                                 "       ^------------^\n"
+                                                 "Undefined parameter type 'doesnotexist'\n"
+                                                 "Please register a ParameterType for 'doesnotexist'\n"));
+        }
+    }
 }