formater: add support for double-quoted fields

Part of #91.

* spot/misc/formater.cc, spot/misc/formater.hh: Here.
* bin/common_output.cc: Adjust automatic output format.
* doc/org/csv.org: Adjust.
* tests/core/lbt.test, tests/core/ltlfilt.test: More tests.
* NEWS: Mention the changes.

NEWS

@@ -94,6 +94,19 @@ New in spot 2.0.3a (not yet released)
   * genltl learned two options, --positive and --negative, to control
     wether formulas should be output after negation or not (or both).
 
+  * The formater used by --format (for ltlfilt, ltlgrind, genltl,
+    randltl) or --stats (for autfilt, dstar2tgba, ltl2tgba, ltldo,
+    randaut) learned to recognize double-quoted fields and double the
+    double-quotes output inbetween as expected from RFC4180-compliant
+    CSV files.  For instance
+      ltl2tgba -f 'a U "b+c"' --stats='"%f",%s'
+    will output
+      "a U ""b+c""",2
+
+  * The --csv-escape option of genltl, ltlfilt, ltlgrind, and randltl
+    is now deprecated.  The option is still here, but hidden and
+    undocumented.
+
   * Arguments passed to -x (in ltl2tgba, ltl2tgta, autfilt, dstar2tgba)
     that are not used are now reported as they might be typos.
     This ocurred a couple of times in our test-suite.  A similar
@@ -1696,7 +1709,7 @@ New in spot 1.2.1 (2013-12-11)
       columns before the formula) and %> (text after) can be used
       with the --format option to alter this output.
 
-    - ltlfile, genltl, randltl, and ltl2tgba have a --csv-escape option
+    - ltlfilt, genltl, randltl, and ltl2tgba have a --csv-escape option
       to help escape formulas in CSV files.
 
     - Please check

bin/common_output.cc

@@ -50,7 +50,9 @@ static const argp_option options[] =
     { "wring", OPT_WRING, nullptr, 0, "output in Wring's syntax", -20 },
     { "utf8", '8', nullptr, 0, "output using UTF-8 characters", -20 },
     { "latex", OPT_LATEX, nullptr, 0, "output using LaTeX macros", -20 },
-    { "csv-escape", OPT_CSV, nullptr, 0,
+    // --csv-escape was deprecated in Spot 2.1, we can remove it at
+    // some point
+    { "csv-escape", OPT_CSV, nullptr, OPTION_HIDDEN,
       "quote the formula for use in a CSV file", -20 },
     { "format", OPT_FORMAT, "FORMAT", 0,
       "specify how each line should be output (default: \"%f\")", -20 },
@@ -268,7 +270,30 @@ output_formula(std::ostream& out,
     {
       if (prefix)
         out << prefix << ',';
-      stream_escapable_formula(out, f, filename, linenum);
+      // For backward compatibility, we still run
+      // stream_escapable_formula when --csv-escape has been given.
+      // But eventually --csv-escape should be removed, and the
+      // formula printed raw.
+      if ((prefix || suffix) && !escape_csv)
+        {
+          std::ostringstream tmp;
+          stream_formula(tmp, f, filename, linenum);
+          std::string tmpstr = tmp.str();
+          if (tmpstr.find_first_of("\",") != std::string::npos)
+            {
+              out << '"';
+              spot::escape_rfc4180(out, tmpstr);
+              out << '"';
+            }
+          else
+            {
+              out << tmpstr;
+            }
+        }
+      else
+        {
+          stream_escapable_formula(out, f, filename, linenum);
+        }
       if (suffix)
         out << ',' << suffix;
     }

doc/org/csv.org

@@ -74,17 +74,18 @@ ltl2tgba -f Xa -f 'G("switch == on" -> F"tab[3,5] < 12")' --stats '%f,%s,%e'
 
 The second line of this input does no conform to [[https://www.rfc-editor.org/rfc/rfc4180.txt][RFC 4180]] because
 non-escaped fields are not allowed to contain comma or double-quotes.
-To fix this, use =ltl2tgba='s =--csv-escape= option: this causes
+To fix this, simply double-quote the =%f= in the argument to =--stats=:
-"=%f=" to produce a double-quoted string properly escaped.
 
 #+BEGIN_SRC sh :results verbatim :exports both
-ltl2tgba -f Xa -f 'G("switch == on" -> F"tab[3,5] < 12")' --stats '%f,%s,%e' --csv-escape
+ltl2tgba -f Xa -f 'G("switch == on" -> F"tab[3,5] < 12")' --stats '"%f",%s,%e'
 #+END_SRC
 
 #+RESULTS:
 : "Xa",3,3
 : "G(!""switch == on"" | F""tab[3,5] < 12"")",2,4
 
+The formater will detect your double-quote and automatically double
+any double quote output between them, as per [[https://www.rfc-editor.org/rfc/rfc4180.txt][RFC 4180]].
 
 The tool [[file:ltlcross.org][=ltlcross=]] has its own =--csv=FILENAME= option to format the
 statistics it gathers in a CSV file, but you have very little control
@@ -150,18 +151,6 @@ ltlfilt -F gen.csv/3 --size-min=8 --relabel=abc
 : and-gf,5,GFa & GFb & GFc & GFd & GFe
 : u-left,5,(((a U b) U c) U d) U e
 
-For security, in case a formula may contain double-quotes or
-commas, you should use the =--csv-escape= option:
-
-#+BEGIN_SRC sh :results verbatim :exports both
-ltlfilt -F gen.csv/3 --size-min=8 --relabel=abc --csv-escape
-#+END_SRC
-#+RESULTS:
-: and-gf,3,"GFa & GFb & GFc"
-: and-gf,4,"GFa & GFb & GFc & GFd"
-: and-gf,5,"GFa & GFb & GFc & GFd & GFe"
-: u-left,5,"(((a U b) U c) U d) U e"
-
 The preservation in the output of the text before and after the
 selected column can be altered using the =--format= option.  The =%<=
 escape sequence represent the (comma-separated) data of all the
@@ -173,7 +162,7 @@ string.
 For instance this moves the first two columns after the formulas.
 
 #+BEGIN_SRC sh :results verbatim :exports both
-ltlfilt -F gen.csv/3 --size-min=8 --csv-escape --format='%f,%<'
+ltlfilt -F gen.csv/3 --size-min=8 --format='"%f",%<'
 #+END_SRC
 #+RESULTS:
 : "GFp1 & GFp2 & GFp3",and-gf,3
@@ -181,14 +170,19 @@ ltlfilt -F gen.csv/3 --size-min=8 --csv-escape --format='%f,%<'
 : "GFp1 & GFp2 & GFp3 & GFp4 & GFp5",and-gf,5
 : "(((p1 U p2) U p3) U p4) U p5",u-left,5
 
+Note that if the =--format= option is not specified, the default
+format is one of: =%f=, =%<,%f=, =%f,%>=, or =%<,%f,%>= depending on
+whether the input CSV had column before and after the selected one.
+Furthermore, the formula field is automatically double-quoted if the
+formula actually use double-quotes, and the input CSV file had more
+than one column.
 
 Typical uses of =ltlfilt= on CSV file include:
 - Filtering lines based on an LTL criterion, as above.
 - Changing the syntax of LTL formulas.  For instance =ltl2tgba='s
   =--stats= option, and =ltlcross='s =--csv= option always output
-  formulas in Spot's format.  If that is inappropriate, simply
+  formulas in Spot's format.  If that is inappropriate, simply use
-  use =ltlfilt= to rewrite the relevant column in your prefered
+  =ltlfilt= to rewrite the relevant column in your preferred syntax.
-  syntax.
 
 * Dealing with header lines
 

spot/misc/formater.cc

@@ -19,8 +19,10 @@
 
 #include "config.h"
 #include <spot/misc/formater.hh>
+#include <spot/misc/escape.hh>
 #include <iostream>
 #include <sstream>
+#include <cstring>
 
 namespace spot
 {
@@ -66,8 +68,22 @@ namespace spot
 
   std::ostream&
   formater::format(const char* fmt)
-    {
+  {
-      for (const char* pos = fmt; *pos; ++pos)
+    for (const char* pos = fmt; *pos; ++pos)
+      {
+        if (*pos == '"')
+          {
+            *output_ << '"';
+            const char* end = strchr(pos + 1, '"');
+            if (!end)
+              continue;
+            std::string tmp(pos + 1, end - (pos + 1));
+            std::ostringstream os;
+            format(os, tmp);
+            escape_rfc4180(*output_, os.str());
+            pos = end;
+            // the end double-quote will be printed below
+          }
         if (*pos != '%')
           {
             *output_ << *pos;
@@ -95,6 +111,7 @@ namespace spot
               break;
             pos = next;
           }
-      return *output_;
+      }
-    }
+    return *output_;
+  }
 }

spot/misc/formater.hh

@@ -173,8 +173,11 @@ namespace spot
     std::ostream&
     format(std::ostream& output, const char* fmt)
     {
+      std::ostream* tmp = output_;
       set_output(output);
-      return format(fmt);
+      format(fmt);
+      set_output(*tmp);
+      return output;
     }
 
     /// Expand the %-sequences in \a fmt, write the result on \a output_.

tests/core/lbt.test

@@ -1,6 +1,6 @@
 #!/bin/sh
 # -*- coding: utf-8 -*-
-# Copyright (C) 2013 Laboratoire de Recherche et
+# Copyright (C) 2013, 2016 Laboratoire de Recherche et
 # Développement de l'Epita (LRDE).
 #
 # This file is part of Spot, a model checking library.
@@ -101,9 +101,16 @@ test `wc -l < formulas.2` -eq 168
 test `wc -l < formulas.3` -eq 168
 test `wc -l < formulas.4` -eq 168
 
+# The --csv-escape option is now obsolete and replaced by double
+# quotes in the format string.  So eventually the first two lines
+# should disappear.
 run 0 $ltlfilt formulas.2 --csv-escape --format='%L,%f' > formulas.5
 run 0 $ltlfilt formulas.5/2 --csv-escape --format='%L,%f' > formulas.6
+run 0 $ltlfilt formulas.2 --format='%L,"%f"' > formulas.5a
+run 0 $ltlfilt formulas.5/2 --format='%L,"%f"' > formulas.6a
 cmp formulas.5 formulas.6
+cmp formulas.5 formulas.5a
+cmp formulas.5a formulas.6a
 
 # Make sure ltl2dstar-style litterals always get quoted.
 test "`$ltlfilt -l --lbt-input -f 'G F a'`" = 'G F "a"'

tests/core/ltlfilt.test

@@ -348,4 +348,14 @@ test "`cat out`" = 'G F "a\"\\b"'
 $ltlfilt --size=foo=2..3  2>stderr && exit 1
 grep 'invalid range.*should start with' stderr
 
+
+cat >out <<EOF
+test1,"""a b"" U c"
+"""a b"" U c",test2
+EOF
+ltlfilt out/1 > out.1
+ltlfilt out/2 > out.2
+diff out out.1
+diff out out.2
+
 true