bin: overhaul default input selection

If no input have been specified, and the standard input is not a tty all
tools now default to reading it.  If standard input is a tty, all tools
display an error message.  Additionally, - is now a shorthand for -F- in
all tools.

* NEWS: Summarize this.
* bin/common_finput.cc, bin/common_finput.hh (check_no_formulas,
check_no_automaton): New functions that implement the above istty()
logic.
* bin/autfilt.cc, bin/dstar2tgba.cc, bin/ltl2tgba.cc, bin/ltl2tgta.cc,
bin/ltlcross.cc, bin/ltldo.cc, bin/ltlgrind.cc: Use these function,
and recognize '-' if it was not the case.
* tests/core/acc_word.test, tests/core/ltldo.test,
tests/core/minusx.test, tests/core/readsave.test,
tests/core/unambig.test: Adjust some tests to exercise this.
* doc/org/autfilt.org, doc/org/csv.org, doc/org/dstar2tgba.org,
doc/org/ltl2tgba.org, doc/org/ltlcross.org, doc/org/ltlfilt.org,
doc/org/oaut.org: Adjust the documentation and simplify some
examples.

NEWS

@@ -2,6 +2,32 @@ New in spot 2.0.3a (not yet released)
 
   Command-line tools:
 
+  * All tools that input formulas or automata (i.e., autfilt,
+    dstar2tgba, ltl2tgba, ltl2tgta, ltlcross, ltldo, ltlfilt,
+    ltlgrind) now have a more homogeneous handling of the default
+    input.
+
+    - If no formula/automaton have been specified, and the standard
+    input is a not a tty, then the default is to read that. This is a
+    change for ltl2tgba and ltl2tgta.  In particular, it simplifies
+
+        genltl --dac | ltl2tgba -F- | autfilt ...
+
+    into
+
+        genltl --dac | ltl2tgba | autfilt ...
+
+    - If standard input is a tty and no other input has been
+    specified, then an error message is printed.  This is a change for
+    autfilt, dstar2tgba, ltlcross, ltldo, ltlfilt, ltlgrind, that used
+    to expect the user to type formula or automata at the terminal,
+    confusing people.
+
+    - All tools now accept - as a shorthand for -F-, to force reading
+    input from the standard input (regardless of whether it is a tty
+    or not).  This is a change for ltl2tgba, ltl2tgta, ltlcross, and
+    ltldo.
+
   * ltldo has a new option --errors=... to specify how to deal
     with errors from executed tools.
 

bin/autfilt.cc

@@ -1116,8 +1116,7 @@ main(int argc, char** argv)
       if (pref_set && !level_set)
         level = spot::postprocessor::High;
 
-      if (jobs.empty())
+      check_no_automaton();
-        jobs.emplace_back("-", true);
 
       if (opt->are_isomorphic)
         {

bin/common_finput.cc

@@ -18,10 +18,12 @@
 // along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 #include "common_finput.hh"
+#include "common_setup.hh"
 #include "error.h"
 
 #include <fstream>
 #include <cstring>
+#include <unistd.h>
 
 enum {
   OPT_LBT = 1,
@@ -353,3 +355,25 @@ job_processor::run()
     }
   return error;
 }
+
+void check_no_formula()
+{
+  if (!jobs.empty())
+    return;
+  if (isatty(STDIN_FILENO))
+    error(2, 0, "No formula to translate?  Run '%s --help' for help.\n"
+          "Use '%s -' to force reading formulas from the standard "
+          "input.", program_name, program_name);
+  jobs.emplace_back("-", true);
+}
+
+void check_no_automaton()
+{
+  if (!jobs.empty())
+    return;
+  if (isatty(STDIN_FILENO))
+    error(2, 0, "No automaton to process?  Run '%s --help' for help.\n"
+          "Use '%s -' to force reading automata from the standard "
+          "input.", program_name, program_name);
+  jobs.emplace_back("-", true);
+}

bin/common_finput.hh

@@ -77,3 +77,8 @@ public:
   char* prefix;
   char* suffix;
 };
+
+// Report and error message or add a default job depending on whether
+// the input is a tty.
+void check_no_formula();
+void check_no_automaton();

bin/dstar2tgba.cc

@@ -180,8 +180,7 @@ main(int argc, char** argv)
   if (int err = argp_parse(&ap, argc, argv, ARGP_NO_HELP, nullptr, nullptr))
     exit(err);
 
-  if (jobs.empty())
+  check_no_automaton();
-    jobs.emplace_back("-", true);
 
   spot::postprocessor post(&extra_options);
   post.set_pref(pref | comp | sbacc);

bin/ltl2tgba.cc

@@ -97,7 +97,10 @@ parse_opt(int key, char* arg, struct argp_state*)
       break;
     case ARGP_KEY_ARG:
       // FIXME: use stat() to distinguish filename from string?
-      jobs.emplace_back(arg, false);
+      if (*arg == '-' && !arg[1])
+        jobs.emplace_back(arg, true);
+      else
+        jobs.emplace_back(arg, false);
       break;
 
     default:
@@ -164,9 +167,7 @@ main(int argc, char** argv)
   if (int err = argp_parse(&ap, argc, argv, ARGP_NO_HELP, nullptr, nullptr))
     exit(err);
 
-  if (jobs.empty())
+  check_no_formula();
-    error(2, 0, "No formula to translate?  Run '%s --help' for usage.",
-          program_name);
 
   try
     {

bin/ltl2tgta.cc

@@ -24,6 +24,7 @@
 #include <fstream>
 
 #include <argp.h>
+#include <unistd.h>
 #include "error.h"
 
 #include "common_setup.hh"
@@ -147,7 +148,10 @@ parse_opt(int key, char* arg, struct argp_state*)
       break;
     case ARGP_KEY_ARG:
       // FIXME: use stat() to distinguish filename from string?
-      jobs.emplace_back(arg, false);
+      if (*arg == '-' && !arg[1])
+        jobs.emplace_back(arg, true);
+      else
+        jobs.emplace_back(arg, false);
       break;
 
     default:
@@ -226,9 +230,7 @@ main(int argc, char** argv)
   if (int err = argp_parse(&ap, argc, argv, ARGP_NO_HELP, nullptr, nullptr))
     exit(err);
 
-  if (jobs.empty())
+  check_no_formula();
-    error(2, 0, "No formula to translate?  Run '%s --help' for usage.",
-          program_name);
 
   try
     {

bin/ltlcross.cc

@@ -408,7 +408,10 @@ parse_opt(int key, char* arg, struct argp_state*)
       products = 0;
       break;
     case ARGP_KEY_ARG:
-      translators.push_back(arg);
+      if (arg[0] == '-' && !arg[1])
+        jobs.emplace_back(arg, true);
+      else
+        translators.push_back(arg);
       break;
     case OPT_AUTOMATA:
       opt_automata = true;
@@ -1443,8 +1446,7 @@ main(int argc, char** argv)
   if (int err = argp_parse(&ap, argc, argv, ARGP_NO_HELP, nullptr, nullptr))
     exit(err);
 
-  if (jobs.empty())
+  check_no_formula();
-    jobs.emplace_back("-", 1);
 
   if (translators.empty())
     error(2, 0, "No translator to run?  Run '%s --help' for usage.",

bin/ltldo.cc

@@ -146,7 +146,10 @@ parse_opt(int key, char* arg, struct argp_state*)
       errors_opt = XARGMATCH("--errors", arg, errors_args, errors_types);
       break;
     case ARGP_KEY_ARG:
-      translators.push_back(arg);
+      if (arg[0] == '-' && !arg[1])
+        jobs.emplace_back(arg, true);
+      else
+        translators.push_back(arg);
       break;
     default:
       return ARGP_ERR_UNKNOWN;
@@ -356,8 +359,7 @@ main(int argc, char** argv)
   if (int err = argp_parse(&ap, argc, argv, ARGP_NO_HELP, nullptr, nullptr))
     exit(err);
 
-  if (jobs.empty())
+  check_no_formula();
-    jobs.emplace_back("-", 1);
 
   if (translators.empty())
     error(2, 0, "No translator to run?  Run '%s --help' for usage.",

bin/ltlgrind.cc

@@ -189,8 +189,7 @@ main(int argc, char* argv[])
 
   mut_opts |= opt_all;
 
-  if (jobs.empty())
+  check_no_formula();
-    jobs.push_back(job("-", true));
 
   mutate_processor processor;
   if (processor.run())

doc/org/autfilt.org

@@ -739,7 +739,7 @@ of the form =cycle{b}=, and display the associated formula (which was
 stored as the name of the automaton by =ltl2tgba=).
 
 #+BEGIN_SRC sh :results verbatim :exports both
-randltl -n -1 a b | ltlfilt --simplify --uniq | ltl2tgba -F- |
+randltl -n -1 a b | ltlfilt --simplify --uniq | ltl2tgba |
   autfilt --accept-word='a&!b;cycle{!a&!b}' --accept-word='!a&!b;cycle{a&b}' \
           --reject-word='cycle{b}' --stats=%M -n 10
 #+END_SRC

doc/org/csv.org

@@ -45,7 +45,7 @@ formulas, and show the resulting number of states (=%s=) and edges
 (=%e=) of the automaton constructed for each formula.
 
 #+BEGIN_SRC sh :results verbatim :exports both
-genltl --and-gf=1..5 --u-left=1..5 | ltl2tgba -F- --stats '%f,%s,%e'
+genltl --and-gf=1..5 --u-left=1..5 | ltl2tgba --stats '%f,%s,%e'
 #+END_SRC
 #+RESULTS:
 #+begin_example

doc/org/dstar2tgba.org

@@ -421,9 +421,9 @@ For instance here is a complex command that will
 1. generate an infinite stream of random LTL formulas with [[file:randltl.org][=randltl=]],
 2. use [[file:ltlfilt.org][=ltlfilt=]] to rewrite the W and M operators away (=--remove-wm=),
    simplify the formulas (=-r=), remove duplicates (=u=) as well as
-   formulas that have a size less then 3 (=--size-min=3=),
+   formulas that have a size less then 3 (=--size-min=3=), and
-3. use =head= to keep only 10 of such formula
+   keep only the 10 first formulas (=-n 10=)
-4. loop to process each of these formula:
+3. loop to process each of these formula:
    - print it
    - then convert the formula into =ltl2dstar='s input format, process
      it with =ltl2dstar= (using =ltl2tgba= as the actual LTL->BA
@@ -438,8 +438,7 @@ deterministic, and =%p= whether the automaton is complete.
 
 #+BEGIN_SRC sh :results verbatim :exports both
 randltl -n -1 --tree-size=10..14 a b c |
-ltlfilt --remove-wm -r -u --size-min=3 |
+ltlfilt --remove-wm -r -u --size-min=3 -n 10 |
-head -n 10 |
 while read f; do
   echo "$f"
   ltlfilt -l -f "$f" |

doc/org/ltl2tgba.org

@@ -835,7 +835,7 @@ For instance we can study the size of the automata generated for the
 right-nested =U= formulas as follows:
 
 #+BEGIN_SRC sh :results verbatim :exports both
-genltl --u-right=1..8 | ltl2tgba -F - --stats '%s states and %e edges for "%f"'
+genltl --u-right=1..8 | ltl2tgba --stats '%s states and %e edges for "%f"'
 #+END_SRC
 #+RESULTS:
 : 2 states and 2 edges for "p1"
@@ -847,7 +847,11 @@ genltl --u-right=1..8 | ltl2tgba -F - --stats '%s states and %e edges for "%f"'
 : 7 states and 28 edges for "p1 U (p2 U (p3 U (p4 U (p5 U (p6 U p7)))))"
 : 8 states and 36 edges for "p1 U (p2 U (p3 U (p4 U (p5 U (p6 U (p7 U p8))))))"
 
-Here =-F -= means that formulas should be read from the standard input.
+Note that because no formula have been passed as argument to
+=ltl2tgba=, it defaulted to reading them from standard input.  Such a
+behaviour can be requested explicitly with =-F -= if needed (e.g., to
+read from standard input in addition to processing other formula
+supplied with =-f=).
 
 When computing the size of an automaton, we distinguish /transitions/
 and /edges/.  An edge between two states is labeled by a Boolean

doc/org/ltlcross.org

@@ -44,8 +44,9 @@ The core of =ltlcross= is a loop that does the following steps:
 
 * Formula selection
 
-Formulas to translate should be specified using the [[file:ioltl.org][common input options]].
+Formulas to translate should be specified using the [[file:ioltl.org][common input
-Standard input is read if no =-f= or =-F= option is given.
+options]].  Standard input is read if it is not connected to a terminal,
+and no =-f= or =-F= options are given.
 
 * Configuring translators
 

doc/org/ltlfilt.org

@@ -15,8 +15,9 @@ formulas.)  It can be used to perform a number of tasks.  Essentially:
 Because it read and write formulas, =ltlfilt= accepts
 all the [[file:ioltl.org][common input and output options]].
 
-Additionally, if no =-f= or =-F= option is specified, =ltlfilt=
+Additionally, if no =-f= or =-F= option is specified, and =ltlfilt=
-will read formulas from the standard input.
+will read formulas from the standard input if it is not connected to a
+terminal.
 
 For instance the following will convert two LTL formulas expressed
 using infix notation (with different names supported for the same

doc/org/oaut.org

@@ -1015,18 +1015,18 @@ using =autfilt -n5=.
 
 #+BEGIN_SRC sh :results verbatim :exports both
 randltl -n -1 a b |
-ltl2tgba -F- |
+ltl2tgba |
 autfilt --states=3 --stats='!(%M)' |
-ltl2tgba -F- |
+ltl2tgba |
 autfilt --states=3 --stats=%M -n5
 #+END_SRC
 
 #+RESULTS:
-: G(F!a & XF(a | G!b))
+: G(b | F(b & Fa))
-: GFb | G(!b & FG!b)
+: (!a | b | (!b & (b W Ga))) & (a | (!b & (b | (!b M F!a))))
-: !a & F((a | b) & (!a | !b))
+: (!a | (!a R b)) & (a | (a U !b))
-: !a | (b R a)
+: !a & F((!a | FG!a) & (a | GFa))
-: !b & X(!b U a)
+: X(!b W a)
 
 Note that the above result can also be obtained without using
 =autfilt= and automata names.  We can use the fact that =ltl2tgba
@@ -1045,13 +1045,15 @@ head -n5 | cut -d, -f2              # return the five first formulas
 #+END_SRC
 
 #+RESULTS:
-: G(F!a & XF(a | G!b))
+: G(b | F(b & Fa))
-: GFb | G(!b & FG!b)
+: (!a | b | (!b & (b W Ga))) & (a | (!b & (b | (!b M F!a))))
-: !a & F((!a | !b) & (a | b))
+: (!a | (!a R b)) & (a | (a U !b))
-: !a | (b R a)
+: !a & F((!a | FG!a) & (a | GFa))
-: !b & X(!b U a)
+: X(!b W a)
-
 
+Note that the =-F-= argument in the first call to =ltl2tgba= is
+superfluous as the tool default to reading from its standard input.
+But we put it there for symmetry with the second call.
 
 #  LocalWords:  num toc html syntaxes ltl tgba sed utf UTF lbtt SCCs
 #  LocalWords:  GraphViz's hoaf HOA LBTT's neverclaim ba SPOT's Gb cn

tests/core/acc_word.test

@@ -34,7 +34,7 @@ ltl2tgba -f 'a U b' |
 ltl2tgba -f 'a U b' | autfilt --accept-word='cycle{!b}' -q && exit 1
 
 # An example from the documentation:
-randltl -n -1 a b | ltlfilt --simplify --uniq | ltl2tgba -F- |
+randltl -n -1 a b | ltlfilt --simplify --uniq | ltl2tgba |
   autfilt --accept-word='a&!b;cycle{!a&!b}' --accept-word='!a&!b;cycle{a&b}' \
           --reject-word='cycle{b}' --stats=%M -n 3 > out
 cat >expect <<EOF

tests/core/ltldo.test

@@ -44,7 +44,7 @@ diff output expected
 
 # Test timeouts.  This test should take 2*2 seconds.
 $genltl --or-g=1..2 |
-run 0 $ltldo -F- -t 'sleep 10; echo %f' -T1 -t 'sleep 10; echo %f' \
+run 0 $ltldo -t 'sleep 10; echo %f' -T1 -t 'sleep 10; echo %f' \
 	     >output 2>stderr
 test -z "`cat output`"
 test 4 = `grep -c warning: stderr`

tests/core/minusx.test

@@ -22,7 +22,7 @@
 set -e
 
 # make sure option -x reports unknown arguments
-ltl2tgba -F- -x foo </dev/null 2>error && exit 1
+ltl2tgba - -x foo </dev/null 2>error && exit 1
 grep "ltl2tgba: option 'foo' was not used" error
 ltl2tgba -F- -x ba-simul,foo,bar </dev/null 2>error && exit 1
 grep -v 'ba-simul' error

tests/core/readsave.test

@@ -115,9 +115,8 @@ diff stdout stdout2
 # exercise both %M and %m.  The nonexistant file should never be
 # open, because the input stream is infinite and autfilt should
 # stop after 10 automata.
-randltl -n -1 a b |
+randltl -n -1 a b | ltl2tgba |
-    ltl2tgba -H -F - |
+    autfilt -F - -F nonexistant --states=3 --edges=..10 --acc-sets=1.. \
-    autfilt -F- -F nonexistant --states=3 --edges=..10 --acc-sets=1.. \
 	     --name='%M, %S states' --stats='<%m>, %e, %a' -n 10 > output
 cat >expected <<EOF
 <F(b | Ga), 3 states>, 5, 1
@@ -278,7 +277,7 @@ autfilt --merge -Hm input --name="%E->%e edges, %T->%t transitions" > output
 diff output expected
 
 
-cat <<EOF | ltl2tgba -x degen-lskip=1 -F- --ba -H > tmp.hoa
+ltl2tgba -x degen-lskip=1 --ba > tmp.hoa <<EOF
 a U b
 false
 !b && Xb && GFa

tests/core/unambig.test

@@ -152,7 +152,7 @@ run 0 $autfilt --check input > output
 test `grep -c unambiguous output` = 0
 
 # Check 1000 random PSL formulas
-randltl --psl -n 1000 3 | $ltl2tgba -U -F- -H |
+randltl --psl -n 1000 3 | $ltl2tgba -U -H |
   $autfilt -v --is-unamb --stats=%M && exit 1
 
 cat >input <<EOF