Make latex_formatC0 based on Jeroen's patch to commonmark.

DESCRIPTION

@@ -21,7 +21,7 @@ URL: https://github.com/dmurdoch/RmdConcord,
 BugReports: https://github.com/dmurdoch/RmdConcord/issues
 Imports: rmarkdown, tools,
          knitr (>= 1.42)
-Suggests: markdown
+Suggests: markdown, commonmark (>= 1.9.0)
 VignetteBuilder: knitr, rmarkdown
 SystemRequirements: pandoc (>=2.11.3 with 'commonmark_x' 
   processing and 'sourcepos' extension, needed for 

NAMESPACE

@@ -6,6 +6,7 @@ export(processConcordance,
        html_with_concordance,
        pdf_documentC0,
        pdf_with_concordance,
+       latex_formatC0,
        test_packages,
        tidy_validate)
 

NEWS.md

@@ -2,7 +2,8 @@
 
 * Added support for `markdown::html_format()` output via new
 `html_formatC()` function.  
-* Support for `markdown::latex_format()` is not planned.
+* Support for `markdown::latex_format()` is planned,
+but requires an update to the `commonmark` package.
 See `?html_formatC()` for some discussion of the issues.
 
 # RmdConcord 0.2.0

R/commonmark.R

@@ -24,3 +24,42 @@ html_formatC <-function(options = list(sourcepos = TRUE), ...) {
   res
 }
 
+latex_formatC0 <- function(latex_engine = "pdflatex",
+                          options = list(sourcepos = TRUE),
+                          defineSconcordance = TRUE,
+                          ...) {
+
+  # Have we got the suggested dependencies?
+  test_packages(pandoc = FALSE)
+
+  sourcepos <- options$sourcepos
+
+  if (is.null(sourcepos))
+    options$sourcepos <- sourcepos <- TRUE
+
+  res <-  markdown::latex_format(options = options,
+                                 latex_engine = latex_engine, ...)
+  res$knitr$opts_knit$concordance <- sourcepos
+  if (sourcepos) {
+
+    # Should produce .tex, not go directly to .pdf
+    res$pandoc$RmdConcord_ext <- res$pandoc$ext
+    res$pandoc$ext = ".tex"
+
+    # Replace the old post_processor with ours
+    res$RmdConcord_post_processor <- res$post_processor
+    res$post_processor <- function(yaml, infile, outfile, ...) {
+      workdir <- dirname(outfile)
+      # We should have a concordance file
+      concordanceFile <- paste0(sans_ext(normalizePath(infile)), "-concordance.tex")
+      origdir <- setwd(workdir)
+      on.exit(setwd(origdir))
+      # Modify the .tex file
+      processLatexConcordance(outfile, followConcordance = concordanceFile, defineSconcordance = defineSconcordance,
+                              infile = infile)
+
+      outfile
+    }
+  }
+  res
+}

R/processConcordance.R

@@ -90,7 +90,8 @@ processConcordance <- function(filename, newfilename = filename,
 processLatexConcordance <- function(filename, newfilename = filename,
                                rename = NULL,
                                followConcordance = NULL,
-                               defineSconcordance = TRUE) {
+                               defineSconcordance = TRUE,
+                               infile = "input") {
   # read the file
   lines <- readLines(filename)
   prevConcordance <- NULL
@@ -106,7 +107,7 @@ processLatexConcordance <- function(filename, newfilename = filename,
   if (defineSconcordance) {
     # Insert \Sconcordance definition
     beginDoc <- match(TRUE, lines == "\\begin{document}")
-    lines <- append(lines, r"(\newcommand{\Sconcordance}[1]{%
+    lines <- append(lines, strsplit(r"(\newcommand{\Sconcordance}[1]{%
 \ifx\pdfoutput\undefined%
 \csname newcount\endcsname\pdfoutput\fi%
 \ifcase\pdfoutput\special{#1}%
@@ -118,8 +119,32 @@ processLatexConcordance <- function(filename, newfilename = filename,
 \endgroup%
 \fi}
 
-)", beginDoc - 1)
+)", "\n")[[1]], beginDoc - 1)
   }
+  source_regexp <- " %sourcepos\\(([0-9]+):[^)]*\\)"
+  sourcecomments <- any(grepl(source_regexp, lines))
+  if (sourcecomments) {
+    # First, remove the source comments from the
+    # header lines
+    for (i in c('title', 'author', 'date')) {
+      regexp <- paste0("(\\\\", i, "\\{.*)", source_regexp, "}$")
+      lines <- sub(regexp, "\\1}", lines)
+    }
+    srcline <- rep(NA_integer_, length(lines))
+    srcfile <- rep(infile, length(lines))
+    regexp <- paste0(".*", source_regexp, "$")
+    datapos <- grep(regexp, lines)
+    if (length(datapos) == 0)
+      stop("No sourcepos attributes found.")
+    srcline[datapos] <- as.integer(sub(regexp, "\\1", lines[datapos]))
+    oldname <- names(rename)
+    for (i in seq_along(rename))
+      srcfile[datapos] <- sub(oldname[i], rename[i], srcfile[datapos], fixed = TRUE)
+    # Remove the sourcepos records now.
+    regexp <- paste0(source_regexp, "$")
+    lines[datapos] <- sub(regexp, "", lines[datapos])
+  } else {
+
   # insert line breaks
   lines <- gsub("\\datapos{", "%\n\\datapos{", lines, fixed = TRUE)
   # don't lose blank lines; they separate paragraphs.
@@ -139,6 +164,7 @@ processLatexConcordance <- function(filename, newfilename = filename,
   # Remove the data-pos records now.  There might be several on a line
   # but we want to ignore them all
   lines[datapos] <- gsub(regexp, "\\3", lines[datapos])
+  }
   offset <- 0
   repeat {
     if (all(is.na(srcline)))

R/test_packages.R

@@ -6,9 +6,15 @@ test_packages <- function(error = TRUE, pandoc = TRUE) {
   if (pandoc && !pandoc_available("2.11.3"))
     message <- "Pandoc 2.11.3 or higher is needed. "
 
-  if (!pandoc && (!requireNamespace("markdown") ||
-                  packageVersion("markdown") < "1.12.1"))
-    message <- c(message, "markdown v 1.12.1 or higher is needed.")
+  if (!pandoc) {
+    if (!requireNamespace("markdown") ||
+        packageVersion("markdown") < "1.12.1")
+      message <- c(message, "markdown v 1.12.1 or higher is needed.")
+    if (!requireNamespace("commonmark") ||
+        packageVersion("commonmark") < "1.9.0" ||
+        !("sourcepos" %in% names(formals(commonmark::markdown_latex))))
+      message <- c(message, "commonmark v 1.9.0 or higher with sourcepos argument in commonmark::markdown_latex() is needed.")
+  }
   if (!length(message))
     TRUE
   else if (error)

man/html_commonmark_document.Rd

@@ -3,7 +3,7 @@
 \alias{html_vignetteC}
 \alias{pdf_documentC0}
 \alias{html_formatC}
-\alias{latex_formatC}
+\alias{latex_formatC0}
 \title{
 R Markdown drivers to add concordance
 }
@@ -26,6 +26,10 @@ pdf_documentC0(latex_engine = "pdflatex",
            defineSconcordance = TRUE,
            ...)
 html_formatC(options = list(sourcepos = TRUE), ...)
+latex_formatC0(latex_engine = "pdflatex",
+               options = list(sourcepos = TRUE),
+               defineSconcordance = TRUE,
+                ...)
 }
 \arguments{
   \item{latex_engine}{
@@ -53,9 +57,11 @@ Each driver modifies the standard driver from \pkg{rmarkdown} or
 and adds concordances.
 }
 \note{
-The \code{pdf_documentC0} function adds the concordances,
+The \code{pdf_documentC0} and \code{latex_formatC0}
+functions add the concordances,
 but they won't be interpreted by LaTeX or PDF previewers.
-To get that to happen, use \code{patchDVI::pdf_documentC}.
+To get that to happen, use \code{patchDVI::pdf_documentC}
+or \code{patchDVI::latex_formatC} respectively.
 
 The \code{html_formatC} function requires \pkg{markdown}
 version 1.12.1 or higher.  If a lower version of that
@@ -68,19 +74,10 @@ be off by a few lines as the underlying Commonmark
 processor only issues source position records once per
 paragraph.
 
-A \code{latex_formatC} driver appears as if it would be
-quite messy and is not currently planned.  The issues are:
-\itemize{
-\item{\pkg{commonmark} doesn't support
-source position attributes in LaTeX output}
-\item{It doesn't allow edits between the parsing and rendering steps.  This is what \code{pdf_documentC} does.}
-\item A possible strategy would be to render first to XML
-(which does keep source position attributes), then convert
-the XML to LaTeX with macros inserted to record source
-positions.  However, \code{markdown::latex_format} produces
-the final LaTeX document in several steps, and would have to
-support this two-stage rendering on some but not all of
-the steps.}
+The \code{latex_formatC0} driver  requires an update
+to the \pkg{commonmark} package, to a version later
+than 1.9.0.  Currently a development version can be installed from Github using
+\code{remotes::install_github("r-lib/commonmark@latex-sourcepos")}.
 }
 \value{
 An R Markdown output format object which will add concordance

man/processLatexConcordance.Rd

@@ -14,7 +14,8 @@ processLatexConcordance(filename,
                         newfilename = filename,
                         rename = NULL,
                         followConcordance = NULL,
-                        defineSconcordance = TRUE)
+                        defineSconcordance = TRUE,
+                        infile = "input")
 }
 \arguments{
   \item{filename}{
@@ -37,6 +38,10 @@ concordances.
   \item{defineSconcordance}{
 Whether to insert the definition of the \verb{\\Sconcordance} macro.
   }
+  \item{infile}{
+The source file to assume for the concordance if it is
+not given in the file.
+  }
 }
 \value{
 Called for the side effect of rewriting the concordance, it returns