#' spec_transaction_with_transaction
#' @family transaction specifications
#' @usage NULL
#' @format NULL
#' @keywords NULL
spec_transaction_with_transaction <- list(
with_transaction_formals = function() {
# <establish formals of described functions>
expect_equal(names(formals(dbWithTransaction)), c("conn", "code", "..."))
},
with_transaction_return_value = function(con) {
#' @return
#' `dbWithTransaction()` returns the value of the executed code.
name <- random_table_name()
expect_identical(dbWithTransaction(con, name), name)
},
#'
with_transaction_error_closed = function(ctx, closed_con) {
#' @section Failure modes:
#' Failure to initiate the transaction
#' (e.g., if the connection is closed
expect_error(dbWithTransaction(closed_con, NULL))
},
with_transaction_error_invalid = function(ctx, invalid_con) {
#' or invalid
expect_error(dbWithTransaction(invalid_con, NULL))
},
with_transaction_error_nested = function(con) {
#' of if [dbBegin()] has been called already)
dbBegin(con)
#' gives an error.
expect_error(dbWithTransaction(con, NULL))
dbRollback(con)
},
with_transaction_success = function(con, table_name) {
#' @section Specification:
#' `dbWithTransaction()` initiates a transaction with `dbBegin()`, executes
#' the code given in the `code` argument, and commits the transaction with
#' [dbCommit()].
dbWriteTable(con, table_name, data.frame(a = 0L), overwrite = TRUE)
dbWithTransaction(
con,
{
dbWriteTable(con, table_name, data.frame(a = 1L), append = TRUE)
expect_equal(check_df(dbReadTable(con, table_name)), data.frame(a = 0:1))
}
)
expect_equal(check_df(dbReadTable(con, table_name)), data.frame(a = 0:1))
},
with_transaction_failure = function(con, table_name) {
#' If the code raises an error, the transaction is instead aborted with
#' [dbRollback()], and the error is propagated.
dbWriteTable(con, table_name, data.frame(a = 0L), overwrite = TRUE)
name <- random_table_name()
expect_error(
dbWithTransaction(
con,
{
dbWriteTable(con, table_name, data.frame(a = 1L), append = TRUE)
stop(name)
}
),
name,
fixed = TRUE
)
expect_equal(check_df(dbReadTable(con, table_name)), data.frame(a = 0L))
},
with_transaction_break = function(con, table_name) {
#' If the code calls `dbBreak()`, execution of the code stops and the
#' transaction is silently aborted.
dbWriteTable(con, table_name, data.frame(a = 0L), overwrite = TRUE)
expect_error(
dbWithTransaction(
con,
{
dbWriteTable(con, table_name, data.frame(a = 1L), append = TRUE)
dbBreak()
}
),
NA
)
expect_equal(check_df(dbReadTable(con, table_name)), data.frame(a = 0L))
},
with_transaction_side_effects = function(con) {
#' All side effects caused by the code
expect_false(exists("a", inherits = FALSE))
#' (such as the creation of new variables)
dbWithTransaction(con, a <- 42)
#' propagate to the calling environment.
expect_identical(get0("a", inherits = FALSE), 42)
},
#
NULL
)
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