Curly Brackets Check

Verify that all the bodies of the if, else, for, while, repeat and function are delimited by curly brackets { }. For instance: if(x > 1){ x } and not if(x > 1) x. Return table message of the line with problems and a corrected version of the submitted function.

Usage

curly_bracket_check(
  x,
  export = FALSE,
  out_path = ".",
  safer_check = TRUE,
  lib_path = NULL,
  error_text = ""
)

Arguments

x

A function name, written without quotes and brackets.

export

Single logical value. Write the corrected function into a file instead of returning it? If TRUE, the file <function name>_safer.R is written in out_path (e.g., fun_safer.R for x = fun or x = pkg::fun). It contains fun_safer <- function(...) ..., so that base::source() recreates the corrected function. Nothing is written if nothing has to be corrected. An error is returned if the file already exists, or if x is not a function name (e.g., function(x){x} or FUN_LIST$fun).

out_path

Single character string indicating the path of the folder where to write the file when export = TRUE. "." (default) means the R working directory. Ignored if export = FALSE.

safer_check

Single logical value. Perform some "safer" checks? If TRUE, checkings are performed before main code running (see the safer-r project): 1) correct lib_path argument value 2) required functions and related packages effectively present in local R libraries and 3) R classical operators (like "<-") not overwritten by another package because of the R scope. Must be set to FALSE if this function is used inside another "safer" function to avoid pointless multiple checkings.

lib_path

Vector of characters specifying the absolute pathways of the directories containing the required packages for the function, if not in the default directories. Useful when R packages are not installed in the default directories because of lack of admin rights. More precisely, lib_path is passed through the new argument of .libPaths() so that the new library paths are unique(c(new, .Library.site, .Library)). Warning: .libPaths() is restored to the initial paths, after function execution. Ignored if NULL (default) or if the safer_check argument is FALSE: only the pathways specified by the current .libPaths() are used for package calling.

error_text

Single character string used to add information in error messages returned by the function, notably if the function is inside other functions, which is practical for debugging. Example: error_text = " INSIDE <PACKAGE_1>::<FUNCTION_1> INSIDE <PACKAGE_2>::<FUNCTION_2>.". If NULL, converted into "".

Value

A table-like message is always printed, with one row per missing { } (column 1: line number; column 2: construct; column 3: code before the body), or a message saying that everything seems fine.

If export = FALSE: the corrected function, or NULL if nothing has to be corrected.

If export = TRUE: NULL, returned invisibly. The corrected function is written in a file (see the export argument).

Details

Comments are ignored. In else if chains, the else is not reported: the chained if is checked on its own.

Bodies reduced to .Primitive(...), like in base::`+`, are skipped, because they cannot be enclosed in curly brackets. Bodies made of UseMethod(...), like in base::mean, are reported.

Correction: a { is added before each reported body and a } after it, separated from the body by a space. The rest of the code is unchanged. The corrected code is checked by parsing it. Lines can become longer than 80 characters. The returned function keeps the environment of the submitted function.

Warning: the comments of the submitted function are lost, in the returned function and in the exported file.

Constructs written with backquotes, like `if`(x > 1, x, 0), may not be checked: use the standard writing.

Line numbers are indicative. They start at the <- function line (#' header lines not counted). Compiled functions, like saferDev::colons_check, have no comments: their line numbers differ from their source file.

Author

Gael Millot

Haiding Wang

Yushi Han

Examples

# Warning: these examples may not work well when using the "Run examples" link
# because of a particular environment. Please, copy-paste in a local environment.
# See also https://safer-r.github.io/saferDev/articles/curly_bracket_check.html
fun1 <- function(x){ if(x > 1){ base::return(x) } }
saferDev::curly_bracket_check(fun1) # everything fine: NULL returned
#> 
#> 
#> AFTER RUNNING saferDev::curly_bracket_check().
#> INSIDE fun1(), EVERYTHING SEEMS CLEAN.
#> 
fun2 <- function(x){ if(x > 1) base::return(x) }
fun2_safer <- saferDev::curly_bracket_check(fun2) # missing { } reported
#> 
#> 
#> 
#> INSIDE fun2(), SOME CURLY BRACKETS {} ARE MISSING AFTER:
#> 
#> LINE	CONSTRUCT		CODE
#> 3	if		if (x > 1) 
#> 
fun2_safer # corrected function
#> function (x) 
#> {
#>     if (x > 1) {
#>         base::return(x)
#>     }
#> }
#> <environment: 0x560c74133e48>
# Write the corrected function in the fun2_safer.R file of a new temporary folder:
tempo_dir <- base::tempfile(pattern = "dir", tmpdir = base::tempdir(), fileext = "")
base::dir.create(path = tempo_dir, showWarnings = TRUE, recursive = FALSE, mode = "0777")
saferDev::curly_bracket_check(x = fun2, export = TRUE, out_path = tempo_dir)
#> 
#> 
#> 
#> INSIDE fun2(), SOME CURLY BRACKETS {} ARE MISSING AFTER:
#> 
#> LINE	CONSTRUCT		CODE
#> 3	if		if (x > 1) 
#> 
#> MODIFIED CODE EXPORTED IN:
#> /tmp/RtmpCOGJEa/dir1411133acf31/fun2_safer.R
#>