feat(epi_slide_opt)!: add .prefix =, .suffix =, .new_col_names =

- BREAKING CHANGE: adjust default output column naming scheme, disallow
  overwriting columns.

NAMESPACE

@@ -114,6 +114,7 @@ importFrom(checkmate,assert_list)
 importFrom(checkmate,assert_logical)
 importFrom(checkmate,assert_numeric)
 importFrom(checkmate,assert_scalar)
+importFrom(checkmate,assert_string)
 importFrom(checkmate,checkInt)
 importFrom(checkmate,check_atomic)
 importFrom(checkmate,check_data_frame)
@@ -176,6 +177,7 @@ importFrom(dplyr,summarize)
 importFrom(dplyr,tibble)
 importFrom(dplyr,ungroup)
 importFrom(ggplot2,autoplot)
+importFrom(glue,glue)
 importFrom(lifecycle,deprecated)
 importFrom(lubridate,as.period)
 importFrom(lubridate,days)
@@ -198,6 +200,7 @@ importFrom(rlang,env)
 importFrom(rlang,expr_label)
 importFrom(rlang,f_env)
 importFrom(rlang,f_rhs)
+importFrom(rlang,is_bare_integerish)
 importFrom(rlang,is_environment)
 importFrom(rlang,is_formula)
 importFrom(rlang,is_function)
@@ -206,6 +209,7 @@ importFrom(rlang,is_quosure)
 importFrom(rlang,list2)
 importFrom(rlang,missing_arg)
 importFrom(rlang,new_function)
+importFrom(rlang,quo_get_env)
 importFrom(rlang,quo_is_missing)
 importFrom(rlang,sym)
 importFrom(rlang,syms)
@@ -230,3 +234,4 @@ importFrom(tidyselect,starts_with)
 importFrom(tsibble,as_tsibble)
 importFrom(utils,capture.output)
 importFrom(utils,tail)
+importFrom(vctrs,vec_data)

R/epi_df.R

@@ -232,7 +232,6 @@ as_epi_df.tbl_df <- function(
     as_of,
     other_keys = character(),
     ...) {
-  # possible standard substitutions for time_value
   x <- rename(x, ...)
   x <- guess_column_name(x, "time_value", time_column_names())
   x <- guess_column_name(x, "geo_value", geo_column_names())
@@ -282,11 +281,11 @@ as_epi_df.tbl_df <- function(
     cli_abort("as_epi_df: `other_keys` can't include \".time_value_counts\"")
   }
 
-  duplicated_time_values <- x %>%
-    group_by(across(all_of(c("geo_value", "time_value", other_keys)))) %>%
-    filter(dplyr::n() > 1) %>%
-    ungroup()
-  if (nrow(duplicated_time_values) > 0) {
+  if (anyDuplicated(x[c("geo_value", "time_value", other_keys)])) {
+    duplicated_time_values <- x %>%
+      group_by(across(all_of(c("geo_value", "time_value", other_keys)))) %>%
+      filter(dplyr::n() > 1) %>%
+      ungroup()
     bad_data <- capture.output(duplicated_time_values)
     cli_abort(
       "as_epi_df: some groups in the data have duplicated time values. epi_df requires a unique time_value per group.",

R/epiprocess-package.R

@@ -6,6 +6,7 @@
 #' @importFrom checkmate anyInfinite anyMissing assert assert_character
 #' @importFrom checkmate assert_class assert_data_frame assert_int assert_list
 #' @importFrom checkmate assert_logical assert_numeric assert_scalar checkInt
+#' @importFrom checkmate assert_string
 #' @importFrom checkmate check_atomic check_data_frame expect_class test_int
 #' @importFrom checkmate check_names
 #' @importFrom checkmate test_subset test_set_equal vname
@@ -16,6 +17,8 @@
 #' @importFrom dplyr select
 #' @importFrom lifecycle deprecated
 #' @importFrom rlang %||%
+#' @importFrom rlang is_bare_integerish
+#' @importFrom vctrs vec_data
 ## usethis namespace: end
 NULL
 

R/slide.R

@@ -537,7 +537,7 @@ get_before_after_from_window <- function(window_size, align, time_type) {
 #'
 #' @template basic-slide-params
 #' @param .col_names <[`tidy-select`][dplyr_tidy_select]> An unquoted column
-#'   name(e.g., `cases`), multiple column names (e.g., `c(cases, deaths)`),
+#'   name (e.g., `cases`), multiple column names (e.g., `c(cases, deaths)`),
 #'   [other tidy-select expression][tidyselect::language], or a vector of
 #'   characters (e.g. `c("cases", "deaths")`). Variable names can be used as if
 #'   they were positions in the data frame, so expressions like `x:y` can be
@@ -564,8 +564,9 @@ get_before_after_from_window <- function(window_size, align, time_type) {
 #'  functions).
 #'
 #' @importFrom dplyr bind_rows mutate %>% arrange tibble select all_of
-#' @importFrom rlang enquo expr_label caller_arg
+#' @importFrom rlang enquo expr_label caller_arg quo_get_env
 #' @importFrom tidyselect eval_select
+#' @importFrom glue glue
 #' @importFrom purrr map map_lgl
 #' @importFrom data.table frollmean frollsum frollapply
 #' @importFrom lubridate as.period
@@ -577,8 +578,7 @@ get_before_after_from_window <- function(window_size, align, time_type) {
 #' # Compute a 7-day trailing average on cases.
 #' cases_deaths_subset %>%
 #'   group_by(geo_value) %>%
-#'   epi_slide_opt(cases, .f = data.table::frollmean, .window_size = 7) %>%
-#'   dplyr::select(geo_value, time_value, cases, cases_7dav = slide_value_cases)
+#'   epi_slide_opt(cases, .f = data.table::frollmean, .window_size = 7)
 #'
 #' # Same as above, but adjust `frollmean` settings for speed, accuracy, and
 #' # to allow partially-missing windows.
@@ -588,11 +588,11 @@ get_before_after_from_window <- function(window_size, align, time_type) {
 #'     cases,
 #'     .f = data.table::frollmean, .window_size = 7,
 #'     algo = "exact", hasNA = TRUE, na.rm = TRUE
-#'   ) %>%
-#'   dplyr::select(geo_value, time_value, cases, cases_7dav = slide_value_cases)
+#'   )
 epi_slide_opt <- function(
     .x, .col_names, .f, ...,
     .window_size = NULL, .align = c("right", "center", "left"),
+    .prefix = NULL, .suffix = NULL, .new_col_names = NULL,
     .ref_time_values = NULL, .all_rows = FALSE) {
   assert_class(.x, "epi_df")
 
@@ -644,21 +644,37 @@ epi_slide_opt <- function(
     )
   }
 
+  # The position of a given column can be differ between input `.x` and
+  # `.data_group` since the grouping step by default drops grouping columns.
+  # To avoid rerunning `eval_select` for every `.data_group`, convert
+  # positions of user-provided `col_names` into string column names. We avoid
+  # using `names(pos)` directly for robustness and in case we later want to
+  # allow users to rename fields via tidyselection.
+  col_names_quo <- enquo(.col_names)
+  pos <- eval_select(col_names_quo, data = .x, allow_rename = FALSE)
+  col_names_chr <- names(.x)[pos]
+
   # Check that slide function `.f` is one of those short-listed from
   # `data.table` and `slider` (or a function that has the exact same
   # definition, e.g. if the function has been reexported or defined
   # locally).
-  if (any(map_lgl(
-    list(frollmean, frollsum, frollapply),
-    ~ identical(.f, .x)
-  ))) {
-    f_from_package <- "data.table"
-  } else if (any(map_lgl(
-    list(slide_sum, slide_prod, slide_mean, slide_min, slide_max, slide_all, slide_any),
-    ~ identical(.f, .x)
-  ))) {
-    f_from_package <- "slider"
-  } else {
+  f_possibilities <-
+    tibble::tribble(
+      ~f, ~package, ~abbr,
+      frollmean, "data.table", "av",
+      frollsum, "data.table", "sum",
+      frollapply, "data.table", "slide",
+      slide_sum, "slider", "sum",
+      slide_prod, "slider", "prod",
+      slide_mean, "slider", "av",
+      slide_min, "slider", "min",
+      slide_max, "slider", "max",
+      slide_all, "slider", "all",
+      slide_any, "slider", "any",
+    )
+  f_info <- f_possibilities %>%
+    filter(map_lgl(.data$f, ~ identical(.f, .x)))
+  if (nrow(f_info) == 0L) {
     # `f` is from somewhere else and not supported
     cli_abort(
       c(
@@ -672,6 +688,7 @@ epi_slide_opt <- function(
       epiprocess__f = .f
     )
   }
+  f_from_package <- f_info$package
 
   user_provided_rtvs <- !is.null(.ref_time_values)
   if (!user_provided_rtvs) {
@@ -702,22 +719,59 @@ epi_slide_opt <- function(
   validate_slide_window_arg(.window_size, time_type)
   window_args <- get_before_after_from_window(.window_size, .align, time_type)
 
+  # Handle output naming
+  assert_string(.prefix, null.ok = TRUE)
+  assert_string(.suffix, null.ok = TRUE)
+  assert_character(.new_col_names, len = length(col_names_chr), null.ok = TRUE)
+  if ((!is.null(.prefix) || !is.null(.suffix)) && !is.null(.new_col_names)) {
+    cli_abort(
+      "Can't use both .prefix/.suffix and .new_col_names at the same time."
+    )
+  }
+  if (is.null(.prefix) && is.null(.suffix) && is.null(.new_col_names)) {
+    .suffix <- "_{.n}{.time_unit_abbr}{.align_abbr}{.f_abbr}"
+  }
+  if (!is.null(.prefix) || !is.null(.suffix)) {
+    .prefix <- .prefix %||% ""
+    .suffix <- .suffix %||% ""
+    if (identical(.window_size, Inf)) {
+      n <- "running_"
+      time_unit_abbr <- ""
+      align_abbr <- ""
+    } else {
+      n <- time_delta_to_n_steps(.window_size, time_type)
+      time_unit_abbr <- time_type_unit_abbr(time_type)
+      align_abbr <- c(right = "", center = "c", left = "l")[[.align]]
+    }
+    glue_env <- rlang::env(
+      .n = n,
+      .time_unit_abbr = time_unit_abbr,
+      .align_abbr = align_abbr,
+      .f_abbr = f_info$abbr,
+      quo_get_env(col_names_quo)
+    )
+    .new_col_names <- unclass(
+      glue(.prefix, .envir = glue_env) +
+        col_names_chr +
+        glue(.suffix, .envir = glue_env)
+    )
+  } else {
+    # `.new_col_names` was provided by user; we don't need to do anything.
+  }
+  if (any(.new_col_names %in% names(.x))) {
+    cli_abort(c(
+      "Naming conflict between new columns and existing columns",
+      "x" = "Overlapping names: {format_varnames(intersect(.new_col_names, names(.x)))}"
+    ))
+  }
+  result_col_names <- .new_col_names
+
   # Make a complete date sequence between min(.x$time_value) and max(.x$time_value).
   date_seq_list <- full_date_seq(.x, window_args$before, window_args$after, time_type)
   all_dates <- date_seq_list$all_dates
   pad_early_dates <- date_seq_list$pad_early_dates
   pad_late_dates <- date_seq_list$pad_late_dates
 
-  # The position of a given column can be differ between input `.x` and
-  # `.data_group` since the grouping step by default drops grouping columns.
-  # To avoid rerunning `eval_select` for every `.data_group`, convert
-  # positions of user-provided `col_names` into string column names. We avoid
-  # using `names(pos)` directly for robustness and in case we later want to
-  # allow users to rename fields via tidyselection.
-  pos <- eval_select(enquo(.col_names), data = .x, allow_rename = FALSE)
-  col_names_chr <- names(.x)[pos]
-  # Always rename results to "slide_value_<original column name>".
-  result_col_names <- paste0("slide_value_", col_names_chr)
   slide_one_grp <- function(.data_group, .group_key, ...) {
     missing_times <- all_dates[!(all_dates %in% .data_group$time_value)]
     # `frollmean` requires a full window to compute a result. Add NA values
@@ -843,6 +897,7 @@ epi_slide_opt <- function(
 epi_slide_mean <- function(
     .x, .col_names, ...,
     .window_size = NULL, .align = c("right", "center", "left"),
+    .prefix = NULL, .suffix = NULL, .new_col_names = NULL,
     .ref_time_values = NULL, .all_rows = FALSE) {
   # Deprecated argument handling
   provided_args <- rlang::call_args_names(rlang::call_match())
@@ -885,6 +940,9 @@ epi_slide_mean <- function(
     ...,
     .window_size = .window_size,
     .align = .align,
+    .prefix = .prefix,
+    .suffix = .suffix,
+    .new_col_names = .new_col_names,
     .ref_time_values = .ref_time_values,
     .all_rows = .all_rows
   )
@@ -904,6 +962,7 @@ epi_slide_mean <- function(
 epi_slide_sum <- function(
     .x, .col_names, ...,
     .window_size = NULL, .align = c("right", "center", "left"),
+    .prefix = NULL, .suffix = NULL, .new_col_names = NULL,
     .ref_time_values = NULL, .all_rows = FALSE) {
   # Deprecated argument handling
   provided_args <- rlang::call_args_names(rlang::call_match())
@@ -945,6 +1004,9 @@ epi_slide_sum <- function(
     ...,
     .window_size = .window_size,
     .align = .align,
+    .prefix = .prefix,
+    .suffix = .suffix,
+    .new_col_names = .new_col_names,
     .ref_time_values = .ref_time_values,
     .all_rows = .all_rows
   )

R/utils.R

@@ -640,7 +640,7 @@ guess_time_type <- function(time_value, time_value_arg = rlang::caller_arg(time_
     return("day")
   } else if (inherits(time_value, "yearmonth")) {
     return("yearmonth")
-  } else if (rlang::is_integerish(time_value)) {
+  } else if (is_bare_integerish(time_value)) {
     return("integer")
   }
 
@@ -1109,3 +1109,68 @@ validate_slide_window_arg <- function(arg, time_type, lower = 1, allow_inf = TRU
     )
   }
 }
+
+
+#' Convert a time delta to a compatible integerish number of steps between time values
+#'
+#' @param time_delta a vector that can be added to time values of time type
+#'   `time_type` to arrive at other time values of that time type, or
+#'   `r lifecycle::badge("experimental")` such a vector with Inf/-Inf entries mixed
+#'   in, if supported by the class of `time_delta`, even if `time_type` doesn't
+#'   necessarily support Inf/-Inf entries. Basically a slide window arg but
+#'   without sign and length restrictions.
+#' @param time_type as in [`validate_slide_window_arg`]
+#' @return [bare integerish][rlang::is_integerish] vector (with possible
+#'   infinite values) that produces the same result as `time_delta` when added
+#'   to time values of time type `time_type`. If the given time type does not
+#'   support infinite values, then it should produce +Inf or -Inf for analogous
+#'   entries of `time_delta`, and match the addition result match the addition
+#'   result for non-infinite values, and product +Inf / -Inf when match the sign
+#'   and of `time_delta`.
+#'
+#' @keywords internal
+time_delta_to_n_steps <- function(time_delta, time_type) {
+  # could be S3 if we're willing to export
+  if (inherits(time_delta, "difftime")) {
+    output_units <- switch(time_type,
+      day = "days",
+      week = "weeks",
+      cli_abort("difftime objects not supported for time_type {format_chr_with_quotes(time_type)}")
+    )
+    units(time_delta) <- output_units # converts number accordingly, doesn't just set attr
+    n_steps <- vec_data(time_delta)
+    if (!is_bare_integerish(n_steps)) {
+      cli_abort("`time_delta` did not appear to contain only integerish numbers
+                 of steps between time values of time type {format_chr_with_quotes(time_type)}")
+    }
+    n_steps
+  } else if (is_bare_integerish(time_delta)) { # (allows infinite values)
+    switch(time_type,
+      day = ,
+      week = ,
+      yearmonth = ,
+      integer = time_delta,
+      cli_abort("Invalid or unsupported time_type {format_chr_with_quotes(time_type)}")
+    )
+  } else {
+    cli_abort("Invalid or unsupported kind of `time_delta`")
+  }
+}
+
+# Using these unit abbreviations happens to make our automatic slide output
+# naming look like taking ISO-8601 duration designations, removing the P, and
+# lowercasing any characters. Fortnightly or sub-daily time types would need an
+# adjustment to remain consistent.
+time_type_unit_abbrs <- c(
+  day = "d",
+  week = "w",
+  yearmon = "m"
+)
+
+time_type_unit_abbr <- function(time_type) {
+  maybe_unit_abbr <- time_type_unit_abbrs[time_type]
+  if (is.na(maybe_unit_abbr)) {
+    cli_abort("Cannot determine the units of time type {format_chr_with_quotes(time_type)}")
+  }
+  maybe_unit_abbr
+}