Localization

By default, messages, warnings and errors are shown in the current locale.

The language can be changed with Sys.setLanguage:

> Sys.setLanguage("es")
> months[1]
Error in months[1] : objeto de tipo 'closure' no es subconjunto

> help(c("mean", "sd"))
Error en help(c("mean", "sd")): 
  'topic' should be a name, length-one character vector or reserved word

PO Files

In the R sources, translations are stored in .po files, e.g.:

utils/po/R-es.po

msgid "no documentation for %s found in package %s"
msgstr "no se ha encontrado documentación para %s en el paquete %s"

msgid "document not found"
msgstr "El documento no se ha encontrado"

…

utils/po/R-es.po

msgid "'topic' should be a name, length-one character vector or reserved word"
msgstr ""

msgid "No documentation for %s in specified packages and libraries:"
msgstr ""

Translation via Weblate

The Weblate instance at https://translate.rx.studio set up by Gergely Daróczi provides a user-friendly interface for contributing translations.

The R Project for Statistical Computing

• Most packages have two components for strings in R and C files
• Also translate strings in the Windows and Mac GUIs

Languages tab

• 27 languages in current release of R, including Spanish and Brazilian Portuguese

Translation interface

• Enter the translation and “Suggest” (if unsure) or “Save and continue” (if confident).

• Sidebar shows alerts and any relevant terms from glossary.

Machine translation

• “Clone to translation” will copy and mark as “needs editing”
• “Accept” will accept suggestion, save and continue

Latin American Contributions

Further work

• Translation of messages in recommended packages:
  • Spanish: 85% translated
  • Brazilian Portuguese: 57% translated
• Updating translations as source messages change
  • R Core Team update 1-2 times a year

Bugs Reports and Feature Requests

Contributors can help in several ways:

Building R as a Barrier to Contribution

• A lot of information to digest
  • Several pages of technical documentation in “R-admin” manual
  • Simplified instructions in R Development Guide, currently for Windows and Ubuntu/Fedora.
• Hard to trouble-shoot issues
• Many pre-requisities to install
• Can interfere with existing R installation

R Dev Container

The R Dev Container provides a development environment that can be run in the browser:

R Dev Container Features

• Launch with GitHub Codespaces (60 hours/month free usage)
• Fixed Linux (Ubuntu) environment, isolated from local system
  • Pre-requisites for building R installed
• Docs with mini tutorials:

R Contribution Workflow

R Contribution Workflow: Build R

Checkout R Sources I

Checkout R Sources II

Get Source of Recommended Packages

Create and Move to Build Directory

Configure the Build I

Configure the Build II

Build R!

Basic check I

Basic check II

Use R-devel in R terminals

R Contribution Workflow: Edit Source

Bug 7084: The Problem

text() recycles coordinate pairs when there are more labels than points

plot(1:7); text(1:2, 2:4, LETTERS[1:4])

Bug 7084: Outline Solution

The comments on the original bug report suggest an outline solution:

if (length(labels) > (n <- max(length(x), length(y))) && n >= 1) {
   ## use labels[1:n]  and warn about length(labels) >= .. or "omitting labels[...]"
}
if (length(labels) < n) { 
  ## recycle labels to length `n`  without a warning
}

Start R I

Start R II

Explore text()

Get methods

Finding the Source with the r-svn GitHub Mirror I

Finding the Source with the r-svn GitHub Mirror II

Finding the Source with the r-svn GitHub Mirror III

Navigating the Source Code in the Container

Debugging text.default()

> debug(text.default)
> plot(1:7); text(1:2, 2:4, LETTERS[1:4])

debugging in: text.default(1:2, 2:4, LETTERS[1:4])
debug: {
    if (!missing(y) && (is.character(y) || is.expression(y))) {
        labels <- y
        y <- NULL
    }
    x <- xy.coords(x, y, recycle = TRUE, setLab = FALSE)
    labels <- as.graphicsAnnot(labels)
    if (!is.null(vfont)) 
        vfont <- c(typeface = pmatch(vfont[1L], Hershey$typeface), 
            fontindex = pmatch(vfont[2L], Hershey$fontindex))
    .External.graphics(C_text, x, labels, adj, pos, offset, vfont, 
        cex, col, font, ...)
    invisible()
}
Browse[1]> 

Press Enter to step through the code

debug: if (!missing(y) && (is.character(y) || is.expression(y))) {
    labels <- y
    y <- NULL
}
Browse[1]> 

debug: x <- xy.coords(x, y, recycle = TRUE, setLab = FALSE)
Browse[1]> 

debug: labels <- as.graphicsAnnot(labels)
Browse[1]>

Test code at this point

Browse[1]> x
$x
[1] 1 2 1

$y
[1] 2 3 4

$xlab
NULL

$ylab
NULL

• The labels are already recycled to length n
• Our warnings should be based on x rather than the original arguments

Return to the Source File

Edit the Code

Edit the Documentation

R Contribution Workflow: Rebuild R

Quit R

Rebuild R

Test reprex

R Contribution Workflow: Run check

Basic check

Fail!

Look at test output

Run test code

R Contribution Workflow: Further edits

Further edits

R Contribution Workflow: Rebuild again

R Contribution Workflow: Run check again

Full check

R Contribution Workflow: Create patch

Create patch

Download patch

View patch

Index: src/library/graphics/R/text.R
===================================================================
--- src/library/graphics/R/text.R   (revision 88304)
+++ src/library/graphics/R/text.R   (working copy)
@@ -27,6 +27,16 @@
    labels <- y; y <- NULL
     }
     x <- xy.coords(x,y, recycle = TRUE, setLab = FALSE)
+
+    if (is.language(labels)) {
+        labels <- as.expression(labels)
+    }
+
+    if (length(labels) > (n <- length(x$x)) && n >= 1) { 
+        labels <- labels[1:n]
+        warning("length(labels) > max(length(x), length(y)). labels truncated to length ", n, ".")
+    }
+
     labels <- as.graphicsAnnot(labels)
     if (!is.null(vfont))
         vfont <- c(typeface = pmatch(vfont[1L], Hershey$typeface),
Index: src/library/graphics/man/text.Rd
===================================================================
--- src/library/graphics/man/text.Rd    (revision 88304)
+++ src/library/graphics/man/text.Rd    (working copy)
@@ -24,7 +24,7 @@
     language objects (names and calls) to expressions, and vectors and
     other classed objects to character vectors by \code{\link{as.character}}.
     If \code{labels} is longer than \code{x} and
-    \code{y}, the coordinates are recycled to the length of \code{labels}.}
+    \code{y}, \code{labels} is truncated to \code{max(length(x), length(y))}.}
   \item{adj}{one or two values in \eqn{[0, 1]} which specify the x
     (and optionally y) adjustment (\sQuote{justification}) of the
     labels, with 0 for left/bottom, 1 for right/top, and 0.5 for

Bug 7084: A Good First Issue

Bug 7084 is an example of a good first issue:

• There is a simple reproducible example.
• An R Core developer (Martin Maechler) agrees it is a bug.
• There is an outline solution approved by the R Core developer.
• The fix only requires editing R code.

Finding Good First issues

R Dev Days