#' spec_meta_has_completed
#' @family meta specifications
#' @usage NULL
#' @format NULL
#' @keywords NULL
spec_meta_has_completed <- list(
has_completed_formals = function() {
# <establish formals of described functions>
expect_equal(names(formals(dbHasCompleted)), c("res", "..."))
},
has_completed_query = function(con) {
#' @return
#' `dbHasCompleted()` returns a logical scalar.
#' For a query initiated by [dbSendQuery()] with non-empty result set,
res <- local_result(dbSendQuery(con, trivial_query()))
#' `dbHasCompleted()` returns `FALSE` initially
expect_false(expect_visible(dbHasCompleted(res)))
#' and `TRUE` after calling [dbFetch()] without limit.
check_df(dbFetch(res))
expect_true(expect_visible(dbHasCompleted(res)))
},
#
has_completed_statement = function(con, table_name) {
#' For a query initiated by [dbSendStatement()],
res <- local_result(dbSendStatement(con, paste0("CREATE TABLE ", table_name, " (a integer)")))
#' `dbHasCompleted()` always returns `TRUE`.
expect_true(expect_visible(dbHasCompleted(res)))
},
#'
has_completed_error = function(con) {
#' @section Failure modes:
res <- dbSendQuery(con, trivial_query())
dbClearResult(res)
#' Attempting to query completion status for a result set cleared with
#' [dbClearResult()] gives an error.
expect_error(dbHasCompleted(res))
},
has_completed_query_spec = function(con) {
#' @section Specification:
#' The completion status for a query is only guaranteed to be set to
#' `FALSE` after attempting to fetch past the end of the entire result.
#' Therefore, for a query with an empty result set,
res <- local_result(dbSendQuery(con, "SELECT * FROM (SELECT 1 as a) AS x WHERE (1 = 0)"))
#' the initial return value is unspecified,
#' but the result value is `TRUE` after trying to fetch only one row.
check_df(dbFetch(res, 1))
expect_true(expect_visible(dbHasCompleted(res)))
},
has_completed_query_spec_partial = function(con) {
#' @section Specification:
#' Similarly, for a query with a result set of length n,
res <- local_result(dbSendQuery(con, trivial_query()))
#' the return value is unspecified after fetching n rows,
check_df(dbFetch(res, 1))
#' but the result value is `TRUE` after trying to fetch only one more
#' row.
check_df(dbFetch(res, 1))
expect_true(expect_visible(dbHasCompleted(res)))
},
#
NULL
)
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