added noop_connection for testing

include/matador/sql/backend_provider.hpp

@@ -6,6 +6,7 @@
 #include <memory>
 #include <string>
 #include <unordered_map>
+#include <unordered_set>
 
 namespace matador::sql {
 
@@ -26,28 +27,50 @@ public:
   const dialect& connection_dialect(const std::string &connection_type);
 
 private:
-  struct backend_context {
+  struct basic_backend_context {
-    backend_context(const std::string &connection_type,
+    virtual ~basic_backend_context() = default;
-                    const std::string &backends_path);
+    [[nodiscard]] virtual connection_impl* create(const connection_info&) = 0;
+    virtual void destroy(connection_impl*) = 0;
+    [[nodiscard]] virtual const sql::dialect* dialect() const = 0;
+  };
+
+  class backend_context final : public basic_backend_context {
+  public:
+    explicit backend_context(const std::string &connection_type);
     backend_context(const backend_context&) = delete;
     backend_context& operator=(const backend_context&) = delete;
     backend_context(backend_context&&) noexcept = default;
     backend_context& operator=(backend_context&&) noexcept = default;
-    ~backend_context();
+    ~backend_context() override;
 
+    [[nodiscard]] connection_impl* create(const connection_info&) override;
+    void destroy(connection_impl *conn) override;
+    [[nodiscard]] const class dialect* dialect() const override;
+
+  private:
     typedef connection_impl*(*create_func)(const connection_info&);
     typedef void (*destroy_func)(connection_impl*);
-    typedef const dialect*(*dialect_func)();
+    typedef const class dialect*(*dialect_func)();
 
     create_func create_connection{};
     destroy_func destroy_connection{};
     dialect_func get_dialect{};
     utils::library lib;
   };
+
+  class noop_backend_context final : public basic_backend_context {
+  public:
+    connection_impl *create(const connection_info &info) override;
+    void destroy(connection_impl *impl) override;
+    [[nodiscard]] const sql::dialect *dialect() const override;
+
+  private:
+    std::unordered_set<std::unique_ptr<connection_impl>> noop_connections_;
+  };
+
 private:
-  using backends_t = std::unordered_map<std::string, std::unique_ptr<backend_context>>;
+  using backends_t = std::unordered_map<std::string, std::unique_ptr<basic_backend_context>>;
   backends_t backends_;
-  std::string backends_path_;
 };
 }
 #endif //QUERY_BACKEND_PROVIDER_HPP

include/matador/sql/noop_connection.hpp

@@ -0,0 +1,26 @@
+#ifndef QUERY_NOOP_CONNECTION_HPP
+#define QUERY_NOOP_CONNECTION_HPP
+
+#include "matador/sql/connection_impl.hpp"
+
+namespace matador::sql {
+
+class noop_connection final : public connection_impl
+{
+public:
+  explicit noop_connection(const connection_info &info);
+
+  void open() override;
+  void close() override;
+  bool is_open() override;
+  size_t execute(const std::string &stmt) override;
+  std::unique_ptr<query_result_impl> fetch(const std::string &stmt) override;
+  std::unique_ptr<statement_impl> prepare(query_context context) override;
+  record describe(const std::string &table) override;
+  bool exists(const std::string &schema_name, const std::string &table_name) override;
+
+private:
+  bool is_open_{false};
+};
+}
+#endif //QUERY_NOOP_CONNECTION_HPP

include/matador/sql/query_data.hpp

@@ -9,14 +9,13 @@
 
 namespace matador::sql {
 
+class query_part;
+
 struct query_data
 {
 //  SqlCommands command;
   std::vector<std::unique_ptr<query_part>> parts;
   std::vector<column_definition> columns;
-  std::unordered_map<std::type_index, table> table_map_by_index;
-  using table_ref = std::reference_wrapper<table>;
-  std::unordered_map<std::string, table_ref> table_map_by_name;
 };
 
 }

include/matador/sql/query_intermediates.hpp

@@ -240,8 +240,7 @@ public:
     if (!schema_->exists<Type>()) {
       schema_->attach<Type>(table.name);
     }
-    data_.parts.push_back(std::make_unique<query_create_table_part>(table, column_generator::generate<Type>(*schema_)));
+    return this->table(table, column_generator::generate<Type>(*schema_));
-    return {connection_, schema_, data_};
   }
 };
 
@@ -261,7 +260,7 @@ public:
   query_into_intermediate into(const sql::table &table, std::initializer_list<column> column_names);
   template<class Type>
   query_into_intermediate into(const sql::table &table)
-  {;
+  {
     data_.parts.push_back(std::make_unique<query_into_part>(table, column_name_generator::generate<Type>(*schema_)));
     return {connection_, schema_, data_};
   }

src/CMakeLists.txt

@@ -32,6 +32,7 @@ set(SQL_SOURCES
   sql/query.cpp
   sql/query_parts.cpp
   sql/query_compiler.cpp
+  sql/noop_connection.cpp
 )
 
 set(SQL_HEADER
@@ -79,6 +80,7 @@ set(SQL_HEADER
   ../include/matador/sql/query_compiler.hpp
   ../include/matador/sql/query_data.hpp
   ../include/matador/sql/table.hpp
+  ../include/matador/sql/noop_connection.hpp
 )
 
 set(QUERY_SOURCES

src/sql/backend_provider.cpp

@@ -1,14 +1,14 @@
 #include "matador/sql/backend_provider.hpp"
+#include "matador/sql/noop_connection.hpp"
+#include "matador/sql/dialect_builder.hpp"
 
-#include "matador/utils/os.hpp"
-
-#include <cstdint>
 #include <stdexcept>
 
 namespace matador::sql {
 backend_provider::backend_provider()
-: backends_path_(utils::os::getenv("MATADOR_BACKENDS_PATH"))
+{
-{}
+  backends_.emplace("noop", std::make_unique<noop_backend_context>());
+}
 
 backend_provider &backend_provider::instance() {
   static backend_provider provider;
@@ -19,31 +19,30 @@ connection_impl *backend_provider::create_connection(const std::string &connecti
 {
   auto it = backends_.find(connection_type);
   if (it == backends_.end()) {
-    it = backends_.emplace(connection_type, std::make_unique<backend_context>(connection_type, backends_path_)).first;
+    it = backends_.emplace(connection_type, std::make_unique<backend_context>(connection_type)).first;
   }
-  return (*it->second->create_connection)(info);
+  return it->second->create(info);
 }
 
 void backend_provider::destroy_connection(const std::string &connection_type, connection_impl *c)
 {
   auto it = backends_.find(connection_type);
   if (it == backends_.end()) {
-    it = backends_.emplace(connection_type, std::make_unique<backend_context>(connection_type, backends_path_)).first;
+    it = backends_.emplace(connection_type, std::make_unique<backend_context>(connection_type)).first;
   }
-  (*it->second->destroy_connection)(c);
+  return it->second->destroy(c);
 }
 
 const dialect &backend_provider::connection_dialect(const std::string &connection_type)
 {
   auto it = backends_.find(connection_type);
   if (it == backends_.end()) {
-    it = backends_.emplace(connection_type, std::make_unique<backend_context>(connection_type, backends_path_)).first;
+    it = backends_.emplace(connection_type, std::make_unique<backend_context>(connection_type)).first;
   }
-  return *(*it->second->get_dialect)();
+  return *it->second->dialect();
 }
 
-backend_provider::backend_context::backend_context(const std::string &connection_type,
+backend_provider::backend_context::backend_context(const std::string &connection_type)
-                                                   const std::string &backends_path)
 {
   if (!lib.load("matador-" + connection_type)) {
     throw std::runtime_error("couldn't load library '" + connection_type + "'");
@@ -54,9 +53,45 @@ backend_provider::backend_context::backend_context(const std::string &connection
   get_dialect = reinterpret_cast<dialect_func >(reinterpret_cast<std::uintptr_t>(lib.function("get_dialect")));
 }
 
+connection_impl *backend_provider::backend_context::create(const connection_info &info)
+{
+  return (create_connection)(info);
+}
+
+void backend_provider::backend_context::destroy(connection_impl *conn)
+{
+  (destroy_connection)(conn);
+}
+
+const class dialect *backend_provider::backend_context::dialect() const
+{
+  return (get_dialect)();
+}
+
 backend_provider::backend_context::~backend_context()
 {
   lib.unload();
 }
 
+connection_impl *backend_provider::noop_backend_context::create(const connection_info &info)
+{
+  return noop_connections_.insert(std::make_unique<noop_connection>(info)).first->get();
+}
+
+void backend_provider::noop_backend_context::destroy(connection_impl *impl)
+{
+  auto it = std::find_if(noop_connections_.begin(), noop_connections_.end(), [impl](const auto &item) {
+    return impl == item.get();
+  });
+  if (it != noop_connections_.end()) {
+    noop_connections_.erase(it);
+  }
+}
+
+const dialect *backend_provider::noop_backend_context::dialect() const
+{
+  static sql::dialect dialect_ = dialect_builder::builder().create().build();
+  return &dialect_;
+}
+
 }

src/sql/noop_connection.cpp

@@ -0,0 +1,52 @@
+#include "matador/sql/noop_connection.hpp"
+#include "matador/sql/query_context.hpp"
+#include "matador/sql/record.hpp"
+
+#include <string>
+#include <memory>
+
+namespace matador::sql {
+noop_connection::noop_connection(const connection_info &info)
+: connection_impl(info) {}
+
+void noop_connection::open()
+{
+  is_open_ = true;
+}
+
+void noop_connection::close()
+{
+  is_open_ = false;
+}
+
+bool noop_connection::is_open()
+{
+  return is_open_;
+}
+
+size_t noop_connection::execute(const std::string &stmt)
+{
+  return 0;
+}
+
+std::unique_ptr<query_result_impl> noop_connection::fetch(const std::string &stmt)
+{
+  return {};
+}
+
+std::unique_ptr<statement_impl> noop_connection::prepare(query_context context)
+{
+  return {};
+}
+
+record noop_connection::describe(const std::string &table)
+{
+  return {};
+}
+
+bool noop_connection::exists(const std::string &schema_name, const std::string &table_name)
+{
+  return false;
+}
+
+}

test/QueryBuilderTest.cpp

@@ -2,13 +2,24 @@
 
 #include <matador/sql/column_definition.hpp>
 #include <matador/sql/condition.hpp>
+#include <matador/sql/connection.hpp>
 #include <matador/sql/dialect_builder.hpp>
 #include <matador/sql/query_builder.hpp>
+#include <matador/sql/query.hpp>
 
 using namespace matador::sql;
 using namespace matador::utils;
 
 TEST_CASE("Create table sql statement string", "[query]") {
+  connection noop("noop://noop.db");
+  auto scm = std::make_shared<schema>("noop");
+  query qu(noop, scm);
+  auto s = qu.create().table({"person"}, {
+    make_pk_column<unsigned long>("id"),
+    make_column<std::string>("name", 255),
+    make_column<unsigned short>("age")
+  }).str();
+
   dialect d = dialect_builder::builder().create().build();
   query_builder query(d);
   auto q = query.create().table("person", {
@@ -17,7 +28,8 @@ TEST_CASE("Create table sql statement string", "[query]") {
       make_column<unsigned short>("age")
   }).compile();
 
-  REQUIRE(q.sql == R"##(CREATE TABLE "person" ("id" BIGINT NOT NULL, "name" VARCHAR(255) NOT NULL, "age" INTEGER NOT NULL, CONSTRAINT PK_person PRIMARY KEY (id)))##");
+  REQUIRE(s == R"##(CREATE TABLE "person" ("id" BIGINT NOT NULL, "name" VARCHAR(255) NOT NULL, "age" INTEGER NOT NULL, CONSTRAINT PK_person PRIMARY KEY (id)))##");
+//  REQUIRE(q.sql == R"##(CREATE TABLE "person" ("id" BIGINT NOT NULL, "name" VARCHAR(255) NOT NULL, "age" INTEGER NOT NULL, CONSTRAINT PK_person PRIMARY KEY (id)))##");
   REQUIRE(q.table_name == "person");
 
   q = query.create().table("person", {