Fix parsing of literate chunks (bug 7838)

 * use verbatimStuff for parsing chunks and make try to follow closely the sweave sytax constraints.
 * merge the two cases for parsing << (noweb or quote)
 * \verb|ff| requires that its parameter is on a single line.

diff --git a/src/tex2lyx/text.cpp b/src/tex2lyx/text.cpp
index fae7eb16af00769e5d6385b8d5178c6c461d29ea..d3ceb58ffdb369f294e1e854e63ca9d5e62e561a 100644 (file)
--- a/src/tex2lyx/text.cpp
+++ b/src/tex2lyx/text.cpp
@@ -1983,77 +1983,45 @@ void copy_file(FileName const & src, string dstname)
 
 
 /// Parse a NoWeb Chunk section. The initial "<<" is already parsed.
-void parse_noweb(Parser & p, ostream & os, Context & context)
+bool parse_noweb(Parser & p, ostream & os, Context & context)
 {
-       // assemble the rest of the keyword
-       string name("<<");
-       bool chunk = false;
-       while (p.good()) {
-               Token const & t = p.get_token();
-               if (t.asInput() == ">" && p.next_token().asInput() == ">") {
-                       name += ">>";
-                       p.get_token();
-                       chunk = (p.good() && p.next_token().asInput() == "=");
-                       if (chunk)
-                               name += p.get_token().asInput();
-                       break;
-               }
-               name += t.asInput();
+       // check whether a chunk is possible here.
+       if (!context.new_layout_allowed ||
+           !context.textclass.hasLayout(from_ascii("Chunk"))) {
+               return false;
        }
 
-       if (!chunk || !context.new_layout_allowed ||
-           !context.textclass.hasLayout(from_ascii("Chunk"))) {
-               cerr << "Warning: Could not interpret '" << name
-                    << "'. Ignoring it." << endl;
-               return;
+       p.pushPosition();
+
+       // read the parameters
+       Parser::Arg stuff = p.verbatimStuff(">>=", false);
+       if (!stuff.first) {
+               p.popPosition();
+               return false;
+       }
+       string chunk = "<<" + stuff.second + ">>="
+               + p.verbatimStuff("\n").second + '\n';
+
+       stuff = p.verbatimStuff("\n@");
+       if (!stuff.first) {
+               p.popPosition();
+               return false;
+       }
+       chunk += stuff.second + "\n@";
+       string post_chunk = p.verbatimStuff("\n").second + '\n';
+       if (post_chunk[0] != ' ' && post_chunk[0] != '\n') {
+               p.popPosition();
+               return false;
        }
+       chunk += post_chunk;
 
-       // We use new_paragraph instead of check_end_layout because the stuff
-       // following the noweb chunk needs to start with a \begin_layout.
-       // This may create a new paragraph even if there was none in the
-       // noweb file, but the alternative is an invalid LyX file. Since
-       // noweb code chunks are implemented with a layout style in LyX they
-       // always must be in an own paragraph.
        context.new_paragraph(os);
        Context newcontext(true, context.textclass,
                &context.textclass[from_ascii("Chunk")]);
-       newcontext.check_layout(os);
-       os << name;
-       while (p.good()) {
-               Token const & t = p.get_token();
-               // We abuse the parser a bit, because this is no TeX syntax
-               // at all.
-               if (t.cat() == catEscape)
-                       os << subst(t.asInput(), "\\", "\n\\backslash\n");
-               else {
-                       ostringstream oss;
-                       Context tmp(false, context.textclass,
-                                   &context.textclass[from_ascii("Chunk")]);
-                       tmp.need_end_layout = true;
-                       tmp.check_layout(oss);
-                       os << subst(t.asInput(), "\n", oss.str());
-               }
-               // The chunk is ended by an @ at the beginning of a line.
-               // After the @ the line may contain a comment and/or
-               // whitespace, but nothing else.
-               if (t.asInput() == "@" && p.prev_token().cat() == catNewline &&
-                   (p.next_token().cat() == catSpace ||
-                    p.next_token().cat() == catNewline ||
-                    p.next_token().cat() == catComment)) {
-                       while (p.good() && p.next_token().cat() == catSpace)
-                               os << p.get_token().asInput();
-                       if (p.next_token().cat() == catComment)
-                               // The comment includes a final '\n'
-                               os << p.get_token().asInput();
-                       else {
-                               if (p.next_token().cat() == catNewline)
-                                       p.get_token();
-                               os << '\n';
-                       }
-                       break;
-               }
-       }
-       newcontext.check_end_layout(os);
+       output_ert(os, chunk, newcontext);
+
+       p.dropPosition();
+       return true;
 }
 
 
@@ -2325,18 +2293,26 @@ void parse_text(Parser & p, ostream & os, unsigned flags, bool outer,
                }
 
                else if (t.asInput() == "<"
-                        && p.next_token().asInput() == "<" && noweb_mode) {
-                       p.get_token();
-                       parse_noweb(p, os, context);
-               }
+                        && p.next_token().asInput() == "<") {
+                       bool has_noweb = false;
+                       if (noweb_mode) {
+                               p.pushPosition();
+                               p.get_token();
+                               has_noweb = parse_noweb(p, os, context);
+                               if (!has_noweb)
+                                       p.popPosition();
+                       }
 
-               else if (t.asInput() == "<" && p.next_token().asInput() == "<") {
-                       context.check_layout(os);
-                       begin_inset(os, "Quotes ");
-                       os << "ard";
-                       end_inset(os);
-                       p.get_token();
-                       skip_braces(p);
+                       if (!has_noweb) {
+                               context.check_layout(os);
+                               begin_inset(os, "Quotes ");
+                               //FIXME: this is a right danish quote;
+                               // why not a left french quote?
+                               os << "ard";
+                               end_inset(os);
+                               p.get_token();
+                               skip_braces(p);
+                       }
                }
 
                else if (t.cat() == catSpace || (t.cat() == catNewline && ! p.isParagraph()))
@@ -3921,9 +3897,12 @@ void parse_text(Parser & p, ostream & os, unsigned flags, bool outer,
                        // set catcodes to verbatim early, just in case.
                        p.setCatcodes(VERBATIM_CATCODES);
                        string delim = p.get_token().asInput();
-                       //FIXME: handle error condition
-                       string const arg = p.verbatimStuff(delim).second;
-                       output_ert_inset(os, "\\verb" + delim + arg + delim, context);
+                       Parser::Arg arg = p.verbatimStuff(delim);
+                       if (arg.first)
+                               output_ert_inset(os, "\\verb" + delim 
+                                                + arg.second + delim, context);
+                       else
+                               cerr << "invalid \\verb command. Skipping" << endl;
                }
 
                // Problem: \= creates a tabstop inside the tabbing environment