feat: detect dependencies in R folder

DESCRIPTION

@@ -20,6 +20,7 @@ Roxygen: list(markdown = TRUE)
 RoxygenNote: 7.2.3
 Imports: 
     rstudioapi,
+    stringr,
     usethis,
     utils
 Suggests: 

R/utils-deps.R

@@ -153,3 +153,196 @@ get_deps_in_namespace <- function() {
 
   deps
 }
+
+
+
+#' **Extract and clean list of packages in the R folder**
+#' 
+#' Detect dependencies in R functions written as `foo::bar()`, `library(foo)`,
+#' `library("foo")`, `library('foo')`, `require(foo)`, `require("foo")`, 
+#' `require('foo')`.
+#' 
+#' @return A named `list` of two `character` vectors:
+#'   - `depends`, packages called with `library(foo)` and `require(foo)`;
+#'   - `imports`, packages called with `foo:bar()`.
+#'   
+#' If a package is called with `library(foo)` and `foo:bar()`, it will be added
+#' only to `depends`.
+#' 
+#' @noRd
+
+get_deps_in_functions_r <- function() {
+
+  check_for_descr_file()
+
+  path <- path_proj()
+
+
+  ## No R/ folder ----
+
+  if (!dir.exists(file.path(path, "R"))) {
+
+    ui_oops("No {ui_value('R/')} folder found")
+
+    return(NULL)
+  }
+
+
+  r_files <- list.files(path = file.path(path, "R"), pattern = "\\.R$", 
+                        full.names = TRUE, ignore.case = TRUE)
+
+
+  ## No .R files in R/ ----
+
+  if (!length(r_files)) {
+
+    ui_oops("The {ui_value('R/')} folder is empty")
+
+    return(NULL)
+
+  }
+
+
+  ## Read R files ----
+
+  content <- lapply(r_files, function(x) readLines(con = x, warn = FALSE))
+
+
+  ## Remove comments ----
+
+  content <- remove_comment_lines(content)
+
+
+  ## Remove messages ----
+
+  content <- remove_messages(content)
+
+
+  ## Functions called as pkg::fun() ----
+
+  deps_imports <- get_colon_syntax_deps(content)
+
+
+  ## Attached Packages (library & require) ----
+
+  deps_depends <- get_attached_deps(content)
+
+
+  ## Remove duplicates ----
+
+  pos <- which(deps_imports %in% deps_depends)
+
+  if (length(pos) > 0) deps_imports <- deps_imports[-pos]
+
+
+  ## Remove project name ----
+
+  pos <- which(deps_depends == basename(path))
+  if (length(pos) > 0) deps_depends <- deps_depends[-pos]
+
+  pos <- which(deps_imports == basename(path))
+  if (length(pos) > 0) deps_imports <- deps_imports[-pos]
+
+
+  ## Clean objects ----
+
+  if (length(deps_depends) == 0) deps_depends <- NULL
+  if (length(deps_imports) == 0) deps_imports <- NULL
+
+  list(
+    "depends" = deps_depends,
+    "imports" = deps_imports
+  )
+}
+
+
+
+#' **Remove comment lines**
+#' 
+#' Remove comment lines in .R files
+#' 
+#' @noRd
+
+remove_comment_lines <- function(x) {
+
+  lapply(x, function(x) {
+    comments <- grep("^\\s{0,}#", x)
+    if (length(comments)) x[-comments] else x })
+}
+
+
+
+#' **Remove messages**
+#' 
+#' Remove messages in `stop()`, `messages()`, `cat()`, `print()`, etc.
+#' 
+#' @noRd
+
+remove_messages <- function(x) {
+
+  x <- lapply(x, function(x) gsub("\".{0,}\'.{0,}\'.{0,}\"", "", x))
+  x <- lapply(x, function(x) gsub("\'.{0,}\".{0,}\".{0,}\'", "", x))
+  x <- lapply(x, function(x) gsub("\".{0,}\\\".{0,}\\\".{0,}\"", "", x))
+  x <- lapply(x, function(x) gsub("\'.{0,}\\\'.{0,}\\\'.{0,}\'", "", x))
+
+  x
+}
+
+
+
+#' **Detect packages called with the double colon syntax**
+#' 
+#' Detect packages called with the double colon syntax (i.e. `foo::bar()`).
+#' 
+#' @noRd
+
+get_colon_syntax_deps <- function(x) {
+
+  pattern <- paste0("[A-Z|a-z|0-9|\\.]{1,}\\s{0,}", 
+                    "::", 
+                    "\\s{0,}[A-Z|a-z|0-9|\\.|_]{1,}")
+
+  funs <- unlist(lapply(x, function(x) {
+    unlist(stringr::str_extract_all(x, pattern))
+  }))
+
+  funs <- gsub("\\s", "", funs)
+
+  deps <- strsplit(funs, "::")
+  deps <- lapply(deps, function(x) x[1])
+  deps <- sort(unique(unlist(deps)))
+
+  if (length(deps) == 0) deps <- NULL
+
+  deps
+}
+
+
+
+#' **Detect attached packages**
+#' 
+#' Detect attached packages, i.e. called by `library()` and `require()`.
+#' 
+#' @noRd
+
+get_attached_deps <- function(x) {
+
+  pattern <- c(paste0("library\\s{0,}\\(\\s{0,}([A-Z|a-z|0-9|\\.]{1,}|",
+                      "\"\\s{0,}[A-Z|a-z|0-9|\\.]{1,}\\s{0,}\"|",
+                      "\'\\s{0,}[A-Z|a-z|0-9|\\.]{1,}\\s{0,}\')"),
+               paste0("require\\s{0,}\\(\\s{0,}([A-Z|a-z|0-9|\\.]{1,}|",
+                      "\"\\s{0,}[A-Z|a-z|0-9|\\.]{1,}\\s{0,}\"|",
+                      "\'\\s{0,}[A-Z|a-z|0-9|\\.]{1,}\\s{0,}\')"))
+  pattern <- paste0(pattern, collapse = "|")
+
+  deps <- unlist(lapply(x, function(x) {
+    unlist(stringr::str_extract_all(x, pattern))
+  }))
+
+  deps <- gsub("\\s", "", deps)
+  deps <- gsub("library\\(|require\\(|\"|\'", "", deps)
+
+  if (length(deps) == 0) deps <- NULL
+
+  deps
+}