first implementation draft for touchstone

Author: lorenzwalthert

API

@@ -6,7 +6,7 @@ cache_activate(cache_name = NULL, verbose = TRUE)
 cache_clear(cache_name = NULL, ask = TRUE)
 cache_deactivate(verbose = TRUE)
 cache_info(cache_name = NULL, format = "both")
-create_style_guide(initialize = default_style_guide_attributes, line_break = NULL, space = NULL, token = NULL, indention = NULL, use_raw_indention = FALSE, reindention = tidyverse_reindention(), style_guide_name = NULL, style_guide_version = NULL, more_specs_style_guide = NULL)
+create_style_guide(initialize = default_style_guide_attributes, line_break = NULL, space = NULL, token = NULL, indention = NULL, use_raw_indention = FALSE, reindention = tidyverse_reindention(), style_guide_name = NULL, style_guide_version = NULL, more_specs_style_guide = NULL, subset_transformers = NULL)
 default_style_guide_attributes(pd_flat)
 specify_math_token_spacing(zero = "'^'", one = c("'+'", "'-'", "'*'", "'/'"))
 specify_reindention(regex_pattern = NULL, indention = 0, comments_only = TRUE)

R/style-guides.R

@@ -174,6 +174,38 @@ tidyverse_style <- function(scope = "tokens",
     )
   }
 
+  subset_transformers <- list(
+    force_assignment_op = "EQ_ASSIGN",
+    add_line_break_after_pipe = "SPECIAL-PIPE",
+    wrap_if_else_while_for_fun_multi_line_in_curly = c("IF", "WHILE", "FOR", "FUNCTION"),
+    remove_line_breaks_in_fun_dec = "FUNCTION",
+    set_space_in_curly_curly = c("'{'", "'}'"),
+    set_space_between_eq_sub_and_comma = "EQ_SUB",
+    remove_space_around_colons = c("':'", "NS_GET_INT", "NS_GET"),
+    remove_space_after_fun_dec = "FUNCTION",
+    remove_space_before_dollar = "'$'",
+    set_space_after_bang_bang = "'!'",
+    remove_space_after_excl = "'!'",
+    style_space_around_tilde = "'~'",
+    add_space_after_for_if_while = c("IF", "WHILE", "FOR"),
+    set_line_break_around_curly_curly = "'{'",
+    indent_braces = c("'('", "'['", "'{'", "')'", "']'", "'}'"),
+    unindent_fun_dec = "FUNCTION",
+    indent_eq_sub = c("EQ_SUB", "EQ_FORMALS"), # TODO rename
+    update_indention_ref_fun_dec = "FUNCTION",
+    remove_space_before_closing_paren = c("')'", "']'"),
+    remove_space_before_opening_paren = c("'('", "'['", "LBB"),
+    remove_space_before_comma = "','",
+    style_space_around_math_token = c(
+      math_token_spacing$zero,
+      math_token_spacing$one
+    ),
+    remove_space_after_opening_paren = c("'('", "'['", "LBB"),
+    start_comments_with_space = "COMMENT",
+    remove_line_break_before_round_closing_after_curly = "'}'",
+    style_line_break_around_curly = "'{'"
+  )
+
   style_guide_name <- "styler::tidyverse_style@https://github.com/r-lib"
   create_style_guide(
     # transformer functions
@@ -187,7 +219,8 @@ tidyverse_style <- function(scope = "tokens",
     reindention            =                    reindention,
     style_guide_name       =               style_guide_name,
     style_guide_version    =                 styler_version,
-    more_specs_style_guide =                           args
+    more_specs_style_guide =                           args,
+    subset_transformers    =            subset_transformers
   )
 }
 
@@ -256,7 +289,8 @@ create_style_guide <- function(initialize = default_style_guide_attributes,
                                reindention = tidyverse_reindention(),
                                style_guide_name = NULL,
                                style_guide_version = NULL,
-                               more_specs_style_guide = NULL) {
+                               more_specs_style_guide = NULL,
+                               subset_transformers = NULL) {
   lst(
     # transformer functions
     initialize = lst(initialize),
@@ -269,7 +303,8 @@ create_style_guide <- function(initialize = default_style_guide_attributes,
     reindention,
     style_guide_name,
     style_guide_version,
-    more_specs_style_guide
+    more_specs_style_guide,
+    subset_transformers
   ) %>%
     map(compact)
 }

R/transform-files.R

@@ -217,13 +217,18 @@ parse_transform_serialize_r <- function(text,
 
   text <- assert_text(text)
   pd_nested <- compute_parse_data_nested(text, transformers, more_specs)
-  blank_lines_to_next_expr <- find_blank_lines_to_next_block(pd_nested)
   if (nrow(pd_nested) == 0) {
     if (warn_empty) {
       warn("Text to style did not contain any tokens. Returning empty string.")
     }
     return("")
   }
+  transformers <- transformers_subset(
+    pd_nested$text[!pd_nested$is_cached],
+    transformers
+  )
+  blank_lines_to_next_expr <- find_blank_lines_to_next_block(pd_nested)
+
 
   text_out <- pd_nested %>%
     split(pd_nested$block) %>%
@@ -245,6 +250,38 @@ parse_transform_serialize_r <- function(text,
   text_out
 }
 
+transformers_subset_impl <- function(x, token) {
+  if (!any(x %in% token)) {
+    x
+  }
+}
+
+#' Remove transformers that are not needed
+#' For every transformer, at least one token must be given to make subsetting.
+#' active.
+transformers_subset <- function(text, transformers) {
+  is_colon <- text == ";"
+  if (any(is_colon)) {
+    # ; can only be parsed when on the same line as other token, not the case
+    # here since text is output of compute_parse_data_nested.
+    text <- c(text[!is_colon], "1;")
+  }
+  token <- unique(tokenize(text)$token)
+  to_remove <- purrr::map(
+    transformers$subset_transformers,
+    transformers_subset_impl, token
+  ) %>%
+    compact() %>% # ise imap, return names directly, save compact()
+    names()
+  if (length(to_remove) > 0) {
+    for (scope in c("initialize", "line_break", "space", "token", "indention")) {
+      transformers[[scope]][to_remove] <- NULL
+      transformers[[scope]] <- purrr::compact(transformers[[scope]])
+    }
+  }
+  transformers
+}
+
 #' Apply transformers to a parse table
 #'
 #' The column `multi_line` is updated (after the line break information is