Merge pull request #1898 from joto/cleanups-flex-output

Cleanups in flex output

Author: lonvia

src/output-flex.cpp

@@ -456,10 +456,9 @@ flex_table_t &output_flex_t::create_flex_table()
         throw fmt_error("Table with name '{}' already exists.", table_name);
     }
 
-    m_tables->emplace_back(table_name);
-    auto &new_table = m_tables->back();
+    auto &new_table = m_tables->emplace_back(table_name);
 
-    lua_pop(lua_state(), 1);
+    lua_pop(lua_state(), 1); // "name"
 
     // optional "schema" field
     lua_getfield(lua_state(), -1, "schema");
@@ -609,14 +608,17 @@ void output_flex_t::setup_flex_table_columns(flex_table_t *table)
             lua_state(), "sql_type", -3, "Column entry", "");
 
         auto &column = table->add_column(name, type, sql_type);
+        lua_pop(lua_state(), 3); // "type", "column", "sql_type"
 
-        column.set_not_null(luaX_get_table_bool(lua_state(), "not_null", -4,
+        column.set_not_null(luaX_get_table_bool(lua_state(), "not_null", -1,
                                                 "Entry 'not_null'", false));
+        lua_pop(lua_state(), 1); // "not_null"
 
         column.set_create_only(luaX_get_table_bool(
-            lua_state(), "create_only", -5, "Entry 'create_only'", false));
+            lua_state(), "create_only", -1, "Entry 'create_only'", false));
+        lua_pop(lua_state(), 1); // "create_only"
 
-        lua_getfield(lua_state(), -6, "projection");
+        lua_getfield(lua_state(), -1, "projection");
         if (!lua_isnil(lua_state(), -1)) {
             if (column.is_geometry_column() ||
                 column.type() == table_column_type::area) {
@@ -626,9 +628,8 @@ void output_flex_t::setup_flex_table_columns(flex_table_t *table)
                                          "geometry and area columns."};
             }
         }
+        lua_pop(lua_state(), 1); // "projection"
 
-        // stack has: projection, create_only, not_null, sql_type, column, type
-        lua_pop(lua_state(), 6);
         ++num_columns;
     });
 
@@ -1445,7 +1446,7 @@ output_flex_t::output_flex_t(std::shared_ptr<middle_query_t> const &mid,
         log_debug("- TABLE {}", qualified_name(table.schema(), table.name()));
         log_debug("  - columns:");
         for (auto const &column : table) {
-            log_debug("    - \"{}\" {} ({}) not_null={} create_only={}",
+            log_debug(R"(    - "{}" {} ({}) not_null={} create_only={})",
                       column.name(), column.type_name(), column.sql_type_name(),
                       column.not_null(), column.create_only());
         }

src/output-flex.hpp

@@ -190,6 +190,7 @@ class output_flex_t : public output_t
     void setup_flex_table_columns(flex_table_t *table);
     void setup_indexes(flex_table_t *table);
 
+    // Get the flex table that is as first parameter on the Lua stack.
     flex_table_t const &get_table_from_param();
 
     void check_context_and_state(char const *name, char const *context,