Implement join on text function (#287)

Author: imilinovic

cpp/CMakeLists.txt

@@ -147,4 +147,5 @@ add_subdirectory(do_module)
 add_subdirectory(periodic_module)
 add_subdirectory(map_module)
 add_subdirectory(collections_module)
+add_subdirectory(text_module)
 add_cugraph_subdirectory(cugraph_module)

cpp/text_module/CMakeLists.txt

@@ -0,0 +1,5 @@
+set(text_module_src
+    text_module.cpp
+    algorithm/text.cpp)
+
+add_query_module(text 1 "${text_module_src}")

cpp/text_module/algorithm/text.cpp

@@ -0,0 +1,34 @@
+#include "text.hpp"
+
+void Text::Join(mgp_list *args, mgp_graph *memgraph_graph, mgp_result *result, mgp_memory *memory) {
+  mgp::memory = memory;
+  const auto arguments = mgp::List(args);
+  const auto record_factory = mgp::RecordFactory(result);
+
+  try {
+    const auto list{arguments[0].ValueList()};
+    const auto delimiter{arguments[1].ValueString()};
+
+    std::string result;
+    if (list.Empty()) {
+      auto record = record_factory.NewRecord();
+      record.Insert(std::string(kResultJoin).c_str(), result);
+      return;
+    }
+
+    auto iterator = list.begin();
+    result += (*iterator).ValueString();
+
+    for (++iterator; iterator != list.end(); ++iterator) {
+      result += delimiter;
+      result += (*iterator).ValueString();
+    }
+
+    auto record = record_factory.NewRecord();
+    record.Insert(std::string(kResultJoin).c_str(), result);
+
+  } catch (const std::exception &e) {
+    record_factory.SetErrorMessage(e.what());
+    return;
+  }
+}

cpp/text_module/algorithm/text.hpp

@@ -0,0 +1,15 @@
+#pragma once
+
+#include <mgp.hpp>
+
+namespace Text {
+
+/* join constants */
+constexpr const std::string_view kProcedureJoin = "join";
+constexpr const std::string_view kJoinArg1 = "strings";
+constexpr const std::string_view kJoinArg2 = "delimiter";
+constexpr const std::string_view kResultJoin = "string";
+
+void Join(mgp_list *args, mgp_graph *memgraph_graph, mgp_result *result, mgp_memory *memory);
+
+}  // namespace Text

cpp/text_module/text_module.cpp

@@ -0,0 +1,21 @@
+#include <mgp.hpp>
+
+#include "algorithm/text.hpp"
+
+extern "C" int mgp_init_module(struct mgp_module *module, struct mgp_memory *memory) {
+  try {
+    mgp::memory = memory;
+
+    AddProcedure(Text::Join, Text::kProcedureJoin, mgp::ProcedureType::Read,
+                 {mgp::Parameter(Text::kJoinArg1, {mgp::Type::List, mgp::Type::String}),
+                  mgp::Parameter(Text::kJoinArg2, mgp::Type::String)},
+                 {mgp::Return(Text::kResultJoin, mgp::Type::String)}, module, memory);
+
+  } catch (const std::exception &e) {
+    return 1;
+  }
+
+  return 0;
+}
+
+extern "C" int mgp_shutdown_module() { return 0; }

e2e/text_test/test_join_1/input.cyp

@@ -0,0 +1,4 @@
+query: >
+  CALL text.join(["idora", "ivan", "matija"], ", ") YIELD string RETURN string;
+output:
+  - string: "idora, ivan, matija"

e2e/text_test/test_join_1/test.yml

@@ -0,0 +1,4 @@
+query: >
+  CALL text.join(["idora", "ivan", "matija"], "") YIELD string RETURN string;
+output:
+  - string: "idoraivanmatija"