Make output matching more robust

After struggling with what seem to be tty driver timing differences,
not to mention different people's shell output, I gave in and removed
the leading CRLF hack from matching.  This means that now no test can
have the same trailing input as the output it matches.

We're also more careful about signal names.

.gitignore

@@ -1,7 +1,8 @@
 # binaries
-helpers/echo-signal
 helpers/echo-exit
+helpers/echo-rot13
+helpers/echo-signal
 helpers/exit-status-0
-helpers/list-fds
 helpers/fd-perms
+helpers/list-fds
 helpers/timeout

helpers/echo-rot13.c

@@ -0,0 +1,35 @@
+#if 0
+set -x "$(dirname $0)/$(basename $0 .c)"
+exec ${CC:-cc} ${CFLAGS:--Wall -Wextra -g} $0 -o $1
+#endif
+
+/* Echo our arguments, rot13'd. */
+
+#include <errno.h>
+#include <spawn.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+static void rot13(char *s)
+{
+    while (*s) {
+        char c = *s|32;
+        if (c >= 'a' && c <= 'm') *s += 13;
+        else if (c >= 'n' && c <= 'z') *s -= 13;
+        ++s;
+    }
+}
+
+int main(int argc, char **argv)
+{
+    for (int i = 1; i < argc; ++i)
+        rot13(argv[i]);
+    if (argc > 1) printf("%s", argv[1]);
+    for (int i = 2; i < argc; ++i)
+        printf(" %s", argv[i]);
+    puts("");
+    return 0;
+}

helpers/echo-signal.c

@@ -9,19 +9,33 @@ exec ${CC:-cc} ${CFLAGS:--Wall -Wextra -g} $0 -o $1
 #include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <unistd.h>
 
-static void echo(int n)
+static char *awaited;
+
+static int int_of_signal_name(char *name)
+{
+    if (!strcmp(name, "INT")) return SIGINT;
+    if (!strcmp(name, "TSTP")) return SIGTSTP;
+    if (!strcmp(name, "CONT")) return SIGCONT;
+    abort();
+}
+
+static void echo(int _)
 {
-    printf("%d\n", n);  /* safe-ish because we don't do anything else.  hah. */
+    (void)_;
+    puts(awaited);  /* never do stuff like this in signal handlers. */
 }
 
 int main(int argc, char **argv)
 {
     struct sigaction action = { .sa_handler = echo };
     if (2 != argc) abort();
-    int sig = atoi(argv[1]);
+    int sig = int_of_signal_name(argv[1]);
+    awaited = argv[1];
     sigaction(sig, &action, NULL);
+    puts("ready");
     pause();
     return 0;
 }

helpers/harness.tcl

@@ -95,7 +95,7 @@ while {![eof $test_file]} {
 seek $test_file 0 start
 
 log_user 0
-set send_slow { 10 .001 }
+set send_slow { 1 .01 }
 setup_execution_environment
 if [catch {spawn $shell} err] {error $err}
 # waiting for first prompt can help
@@ -125,12 +125,13 @@ proc not_ok {} {
 proc is {x} { uplevel 1 [list if $x {ok} {not_ok}]}
 
 proc expect_line {line} {
-    # NB: the \r\n at the start of the line here breaks fish, and
-    # makes this somewhat unreliable, but it's tricky to find an
-    # alternative that is as simple and stops cat from passing the
-    # tests.
+    # NB: this is fairly unreliable, and we should have some lint
+    # where we reject tests whose expected output would match the tail
+    # of their input.  There doesn't seem to be a better way to deal
+    # with the output and timing differences between shells, short of
+    # going full ptrace as mentioned previously.
     set rv [expect {
-        "\r\n$line\r\n" {return 1}
+        "$line\r\n" {return 1}
         default {return 0}
     }]
     expect *

stage_1/01-fork-exec.t

@@ -2,5 +2,7 @@
 ← foo bar
 → tr a-z n-za-m⏎foo bar baz⏎^D
 ← sbb one onm
+→ ./helpers/echo-rot13 foo bar⏎
+← sbb one
 → ./helpers/echo-exit ./helpers/successful-exit-status⏎
 ← 0

stage_1/03-cd-changes-directory.t

@@ -1,5 +1,6 @@
 → /bin/pwd⏎
 ≠ /tmp
 → cd /tmp⏎
+→ cd ..⏎
 → /bin/pwd⏎
-← /tmp
+← /

stage_1/04-semicolon-separates-commands.t

@@ -3,5 +3,5 @@
 ← foobarbaz
 → cd /tmp; pwd⏎
 ← /tmp
-→ false; echo foo⏎
-← foo
+→ false; echo-rot13 foo⏎
+← sbb

stage_1/05-and-or-chaining.t

@@ -1,13 +1,15 @@
 # POSIX calls these AND Lists and OR Lists
-→ true && echo foo⏎
-← foo
-→ false && echo foo⏎
-≠ foo
-→ true && false && echo foo⏎
-≠ foo
-→ false || echo foo⏎
-← foo
-→ true || false || echo foo⏎
-≠ foo
-→ false || true && echo foo⏎
-← foo
+→ true && echo-rot13 foo⏎
+← sbb
+→ false && echo-rot13 foo⏎
+≠ sbb
+→ true && false && echo-rot13 foo⏎
+≠ sbb
+→ false || echo-rot13 foo⏎
+← sbb
+→ true || false || echo-rot13 foo⏎
+≠ sbb
+→ false || true && echo-rot13 foo⏎
+← sbb
+→ nonexistent-command || echo-rot13 zim⏎
+← mvz

stage_1/07-subshell.t

@@ -4,7 +4,7 @@
 ← /tmp
 → pwd⏎
 ≠ /tmp
-→ (exit 1) && echo foo⏎
-≠ foo
-→ (exit 0 && exit 1) && echo foo⏎
-← foo
+→ (exit 1) && echo-rot13 foo⏎
+≠ sbb
+→ (exit 0 && exit 1) && echo-rot13 foo⏎
+← sbb

stage_1/08-bang-negates-exit-code.t

@@ -1,6 +1,6 @@
-→ ! false && echo foo⏎
-← foo
-→ ! true && echo foo⏎
-≠ foo
-→ ! true || echo foo⏎
-← foo
+→ ! false && echo-rot13 foo⏎
+← sbb
+→ ! true && echo-rot13 foo⏎
+≠ sbb
+→ ! true || echo-rot13 foo⏎
+← sbb

stage_1/10-multiline-list.t

@@ -1,2 +1,2 @@
-→ true &&⏎false ||⏎echo foo ||⏎echo bar⏎
-← foo
+→ true &&⏎false ||⏎echo-rot13 foo ||⏎echo-rot13 bar⏎
+← sbb

stage_2/02-redirections.t

@@ -8,8 +8,8 @@
 # NB echo -n isn't portable...
 → echo -n a > foo ; echo b >> foo ; cat foo⏎
 ← ab
-→ cat < /non-existent-file || echo foo⏎
-← foo
+→ cat < /non-existent-file || echo-rot13 foo⏎
+← sbb
 → cat /non-existent-file 2>foo || grep -c . <foo⏎
 ← 1
 → echo quux > foo && cat < foo⏎

stage_2/04-ensure-pipes-are-closed.t

@@ -1,4 +1,4 @@
 # This will hang in the case of a very common bug: you forget to close
 # the other ends of the pipe.
-→ cat </etc/passwd | cat | cat | cat >/dev/null | echo foo⏎
-← foo
+→ cat </etc/passwd | cat | cat | cat >/dev/null | echo-rot13 foo⏎
+← sbb

stage_2/07-bang-only-at-start-of-pipelines.t

@@ -1,5 +1,5 @@
 # Would prefer to test this but mksh doesn't agree
 #→ echo zim | ! tr z b | grep -qc bim || echo foo⏎
 #≠ foo
-→ ! echo zim | tr z b | grep -qc bim || echo foo⏎
-← foo
+→ ! echo zim | tr z b | grep -qc bim || echo-rot13 foo⏎
+← sbb

stage_2/08-builtin-in-pipeline.t

@@ -1,4 +1,4 @@
 → echo foo | cd /tmp | pwd⏎
 ≠ /tmp
-→ echo foo | cd /tmp | echo bar⏎
-← bar
+→ echo foo | cd /tmp | echo-rot13 bar⏎
+← one

stage_3/01-executed-command-receives-signals.t

@@ -1,10 +1,9 @@
 # this would be nicer if we already had $@...
-→ echo-signal 2⏎
+→ echo-signal INT⏎
+← ready
 → ^C⏎
-← 2
-→ cat⏎
-→ ^\⏎echo foo⏎
-← foo
-→ echo-signal 20⏎
+← INT
+→ echo-signal TSTP⏎
+← ready
 → ^Z⏎
-← 20
+← TSTP

stage_3/02-job-control-with-fg-bg.t

@@ -1,12 +1,14 @@
-→ echo-signal 18⏎
+→ echo-signal CONT⏎
+← ready
 → ^Z
-→ echo foo⏎
-← foo
+→ echo-rot13 foo⏎
+← sbb
 → fg⏎
-← 18
-→ echo-signal 2 &⏎
-→ echo foo⏎
-← foo
+← CONT
+→ echo-signal INT &⏎
+← ready
+→ echo-rot13 foo⏎
+← sbb
 → fg⏎
 → ^C⏎
-← 2
+← INT

stage_3/03-sequencing-with-suspend.t

@@ -1,5 +1,6 @@
-→ echo-signal 2 & echo foo⏎
-← foo
+→ echo-signal INT & sleep 1; echo-rot13 foo⏎
+← ready
+← sbb
 → fg⏎
 → ^C⏎
-← 2
+← INT

stage_3/05-sigquit.t

@@ -1,2 +1,4 @@
-→ cat⏎^\⏎echo foo⏎
-← foo
+→ cat⏎^\⏎echo-rot13 foo⏎
+← sbb
+→ ^\^\echo-rot13 blah⏎
+← oynu

stage_4/05-commands-can-be-quoted.t

@@ -1,4 +1,6 @@
 → e'ch'o foo⏎
 ← foo
-→ ''''""/"b"i'n/e'"c"ho''"" yup⏎
+→ ''''""/"b"i'n/e'"c"ho''"" yup; true⏎
 ← yup
+→ ""'echo'"-"rot1'3' yup⏎
+← lhc

stage_4/10-tilde-expansion.t

@@ -1,4 +1,4 @@
-→ echo ~⏎
+→ echo ~; true⏎
 ≠ ~
 # XXX this will vary by system; use magic.
 → echo ~root⏎

stage_5/01-tab-completion.t

@@ -1,4 +1,4 @@
 # not POSIX
 → touch foo bar⏎
-→ ech^I f^I b^I⏎
-← foo bar
+→ ech^I-rot^I f^I b^I⏎
+← sbb one

stage_5/02-basic-history.t

@@ -1,5 +1,6 @@
-→ echo foo⏎
-← foo
-→ echo bar⏎
+→ echo-rot13 foo⏎
+← sbb
+→ echo-rot13 bar⏎
+← one
 → ⇑⇑⏎
-← foo
+← sbb

stage_5/03-search-with-control-r.t

@@ -1,7 +1,7 @@
 → true⏎
-→ echo foo⏎
-← foo
-→ echo bar⏎
-← bar
+→ echo-rot13 foo⏎
+← sbb
+→ echo-rot13 bar⏎
+← one
 → ^Rf⏎
-← foo
+← sbb