Add a Negation token type to PointerTemplate

Signed-off-by: Juan Cruz Viotti <[email protected]>
sourcemeta · Feb 12, 2025 · 8c911bc · 8c911bc
1 parent 78f9c0a
commit 8c911bc
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Showing 3 changed files with 52 additions and 1 deletion.
diff --git a/src/core/jsonpointer/include/sourcemeta/core/jsonpointer_template.h b/src/core/jsonpointer/include/sourcemeta/core/jsonpointer_template.h
@@ -20,10 +20,14 @@ template <typename PointerT> class GenericPointerTemplate {
     auto operator==(const Condition &) const noexcept -> bool = default;
     auto operator<(const Condition &) const noexcept -> bool { return false; }
   };
+  struct Negation {
+    auto operator==(const Negation &) const noexcept -> bool = default;
+    auto operator<(const Negation &) const noexcept -> bool { return false; }
+  };
   using Regex = typename PointerT::Value::String;
   using Token = typename PointerT::Token;
   using Container =
-      std::vector<std::variant<Wildcard, Condition, Regex, Token>>;
+      std::vector<std::variant<Wildcard, Condition, Negation, Regex, Token>>;
 
   /// This constructor creates an empty JSON Pointer template. For example:
   ///

diff --git a/src/core/jsonpointer/stringify.h b/src/core/jsonpointer/stringify.h
@@ -474,6 +474,11 @@ auto stringify(const PointerT &pointer,
         stream.put(internal::token_pointer_tilde<CharT>);
         stream.put('?');
         stream.put(internal::token_pointer_tilde<CharT>);
+      } else if (std::holds_alternative<typename PointerT::Negation>(token)) {
+        stream.put(internal::token_pointer_slash<CharT>);
+        stream.put(internal::token_pointer_tilde<CharT>);
+        stream.put('!');
+        stream.put(internal::token_pointer_tilde<CharT>);
       } else {
         stringify_token<CharT, Traits, Allocator, typename PointerT::Token>(
             std::get<typename PointerT::Token>(token), stream,

diff --git a/test/jsonpointer/jsonpointer_template_test.cc b/test/jsonpointer/jsonpointer_template_test.cc
@@ -164,6 +164,36 @@ TEST(JSONPointer_template, equality_with_condition_wildcard_false) {
   EXPECT_NE(left, right);
 }
 
+TEST(JSONPointer_template, equality_with_negation_wildcard_true) {
+  const sourcemeta::core::Pointer prefix{"foo", "bar"};
+  const sourcemeta::core::Pointer suffix{"baz"};
+
+  sourcemeta::core::PointerTemplate left{prefix};
+  left.emplace_back(sourcemeta::core::PointerTemplate::Negation{});
+  left.push_back(suffix);
+
+  sourcemeta::core::PointerTemplate right{prefix};
+  right.emplace_back(sourcemeta::core::PointerTemplate::Negation{});
+  right.push_back(suffix);
+
+  EXPECT_EQ(left, right);
+}
+
+TEST(JSONPointer_template, equality_with_negation_wildcard_false) {
+  const sourcemeta::core::Pointer prefix{"foo", "bar"};
+  const sourcemeta::core::Pointer suffix{"baz"};
+
+  sourcemeta::core::PointerTemplate left{prefix};
+  left.emplace_back(sourcemeta::core::PointerTemplate::Negation{});
+  left.push_back(suffix);
+
+  sourcemeta::core::PointerTemplate right{prefix};
+  right.push_back(suffix);
+  right.emplace_back(sourcemeta::core::PointerTemplate::Negation{});
+
+  EXPECT_NE(left, right);
+}
+
 TEST(JSONPointer_template, pop_back) {
   const sourcemeta::core::Pointer base{"foo", "bar"};
   sourcemeta::core::PointerTemplate pointer{base};
@@ -244,6 +274,18 @@ TEST(JSONPointer_template, stringify_condition) {
   EXPECT_EQ(stream.str(), "/foo/bar/~?~");
 }
 
+TEST(JSONPointer_template, stringify_negation) {
+  const sourcemeta::core::Pointer prefix{"foo", "bar"};
+
+  sourcemeta::core::PointerTemplate pointer{prefix};
+  pointer.emplace_back(sourcemeta::core::PointerTemplate::Negation{});
+
+  std::ostringstream stream;
+  sourcemeta::core::stringify(pointer, stream);
+
+  EXPECT_EQ(stream.str(), "/foo/bar/~!~");
+}
+
 TEST(JSONPointer_template, concat_move) {
   const sourcemeta::core::Pointer pointer_left{"foo"};
   const sourcemeta::core::Pointer pointer_right{"bar", "baz"};