=head1 NAME
-diagnostics - Perl compiler pragma to force verbose warning diagnostics
-
-splain - standalone program to do the same thing
+diagnostics, splain - produce verbose warning diagnostics
=head1 SYNOPSIS
-As a pragma:
+Using the C<diagnostics> pragma:
use diagnostics;
use diagnostics -verbose;
enable diagnostics;
disable diagnostics;
-Aa a program:
+Using the C<splain> standalone filter program:
perl program 2>diag.out
splain [-v] [-p] diag.out
+Using diagnostics to get stack traces from a misbehaving script:
+
+ perl -Mdiagnostics=-traceonly my_script.pl
=head1 DESCRIPTION
=head2 The C<diagnostics> Pragma
This module extends the terse diagnostics normally emitted by both the
-perl compiler and the perl interpreter, augmenting them with the more
+perl compiler and the perl interpreter (from running perl with a -w
+switch or C<use warnings>), augmenting them with the more
explicative and endearing descriptions found in L<perldiag>. Like the
other pragmata, it affects the compilation phase of your program rather
than merely the execution phase.
Warnings dispatched from perl itself (or more accurately, those that match
descriptions found in L<perldiag>) are only displayed once (no duplicate
-descriptions). User code generated warnings ala warn() are unaffected,
+descriptions). User code generated warnings a la warn() are unaffected,
allowing duplicate user messages to be displayed.
+This module also adds a stack trace to the error message when perl dies.
+This is useful for pinpointing what
+caused the death. The B<-traceonly> (or
+just B<-t>) flag turns off the explanations of warning messages leaving just
+the stack traces. So if your script is dieing, run it again with
+
+ perl -Mdiagnostics=-traceonly my_bad_script
+
+to see the call stack at the time of death. By supplying the B<-warntrace>
+(or just B<-w>) flag, any warnings emitted will also come with a stack
+trace.
+
=head2 The I<splain> Program
While apparently a whole nuther program, I<splain> is actually nothing
=cut
use strict;
-use 5.005_64;
+use 5.009001;
use Carp;
+$Carp::Internal{__PACKAGE__.""}++;
-our $VERSION = v1.0;
+our $VERSION = '1.34';
our $DEBUG;
our $VERBOSE;
our $PRETTY;
+our $TRACEONLY = 0;
+our $WARNTRACE = 0;
use Config;
-my($privlib, $archlib) = @Config{qw(privlibexp archlibexp)};
+use Text::Tabs 'expand';
+my $privlib = $Config{privlibexp};
if ($^O eq 'VMS') {
require VMS::Filespec;
$privlib = VMS::Filespec::unixify($privlib);
- $archlib = VMS::Filespec::unixify($archlib);
}
my @trypod = (
- "$archlib/pod/perldiag.pod",
- "$privlib/pod/perldiag-$Config{version}.pod",
"$privlib/pod/perldiag.pod",
- "$archlib/pods/perldiag.pod",
- "$privlib/pods/perldiag-$Config{version}.pod",
"$privlib/pods/perldiag.pod",
);
# handy for development testing of new warnings etc
(my $PODFILE) = ((grep { -e } @trypod), $trypod[$#trypod])[0];
$DEBUG ||= 0;
-my $WHOAMI = ref bless []; # nobody's business, prolly not even mine
local $| = 1;
local $_;
+local $.;
my $standalone;
my(%HTML_2_Troff, %HTML_2_Latin_1, %HTML_2_ASCII_7);
if (caller) {
INCPATH: {
- for my $file ( (map { "$_/$WHOAMI.pm" } @INC), $0) {
+ for my $file ( (map { "$_/".__PACKAGE__.".pm" } @INC), $0) {
warn "Checking $file\n" if $DEBUG;
if (open(POD_DIAG, $file)) {
while (<POD_DIAG>) {
*THITHER = $standalone ? *STDOUT : *STDERR;
+my %transfmt = ();
my $transmo = <<EOFUNC;
sub transmo {
#local \$^W = 0; # recursive warnings we do NOT need!
- study;
EOFUNC
my %msg;
local $/ = '';
local $_;
my $header;
+ my @headers;
my $for_item;
+ my $seen_body;
while (<POD_DIAG>) {
+ sub _split_pod_link {
+ $_[0] =~ m'(?:([^|]*)\|)?([^/]*)(?:/("?)(.*)\3)?'s;
+ ($1,$2,$4);
+ }
+
unescape();
if ($PRETTY) {
sub noop { return $_[0] } # spensive for a noop
sub bold { my $str =$_[0]; $str =~ s/(.)/$1\b$1/g; return $str; }
sub italic { my $str = $_[0]; $str =~ s/(.)/_\b$1/g; return $str; }
- s/[BC]<(.*?)>/bold($1)/ges;
- s/[LIF]<(.*?)>/italic($1)/ges;
+ s/C<<< (.*?) >>>|C<< (.*?) >>|[BC]<(.*?)>/bold($+)/ges;
+ s/[IF]<(.*?)>/italic($1)/ges;
+ s/L<(.*?)>/
+ my($text,$page,$sect) = _split_pod_link($1);
+ defined $text
+ ? $text
+ : defined $sect
+ ? italic($sect) . ' in ' . italic($page)
+ : italic($page)
+ /ges;
+ s/S<(.*?)>/
+ $1
+ /ges;
} else {
- s/[BC]<(.*?)>/$1/gs;
- s/[LIF]<(.*?)>/$1/gs;
+ s/C<<< (.*?) >>>|C<< (.*?) >>|[BC]<(.*?)>/$+/gs;
+ s/[IF]<(.*?)>/$1/gs;
+ s/L<(.*?)>/
+ my($text,$page,$sect) = _split_pod_link($1);
+ defined $text
+ ? $text
+ : defined $sect
+ ? qq '"$sect" in $page'
+ : $page
+ /ges;
+ s/S<(.*?)>/
+ $1
+ /ges;
}
unless (/^=/) {
if (defined $header) {
) )
{
next;
- }
+ }
+ $_ = expand $_;
s/^/ /gm;
$msg{$header} .= $_;
+ for my $h(@headers) { $msg{$h} .= $_ }
+ ++$seen_body;
undef $for_item;
}
next;
}
- unless ( s/=item (.*?)\s*\z//) {
+
+ # If we have not come across the body of the description yet, then
+ # the previous header needs to share the same description.
+ if ($seen_body) {
+ @headers = ();
+ }
+ else {
+ push @headers, $header if defined $header;
+ }
+
+ unless ( s/=item (.*?)\s*\z//s) {
if ( s/=head1\sDESCRIPTION//) {
$msg{$header = 'DESCRIPTION'} = '';
}
elsif( s/^=for\s+diagnostics\s*\n(.*?)\s*\z// ) {
$for_item = $1;
- }
+ }
+ elsif( /^=back/ ) { # Stop processing body here
+ undef $header;
+ undef $for_item;
+ $seen_body = 0;
+ next;
+ }
next;
}
- # strip formatting directives in =item line
- $header = $for_item || $1;
- undef $for_item;
+ if( $for_item ) { $header = $for_item; undef $for_item }
+ else {
+ $header = $1;
+
+ $header =~ s/\n/ /gs; # Allow multi-line headers
+ }
+
+ # strip formatting directives from =item line
$header =~ s/[A-Z]<(.*?)>/$1/g;
- if ($header =~ /%[csd]/) {
- my $rhs = my $lhs = $header;
- if ($lhs =~ s/(.*?)%d(?!%d)(.*)/\Q$1\E-?\\d+\Q$2\E/g) {
- $lhs =~ s/\\%s/.*?/g;
- } else {
- # if i had lookbehind negations,
- # i wouldn't have to do this \377 noise
- $lhs =~ s/(.*?)%s/\Q$1\E.*?\377/g;
- $lhs =~ s/\377([^\377]*)$/\Q$1\E/;
- $lhs =~ s/\377//g;
- $lhs =~ s/\.\*\?$/.*/; # Allow %s at the end to eat it all
- }
- $lhs =~ s/\\%c/./g;
- $transmo .= " s{^$lhs}\n {\Q$rhs\E}s\n\t&& return 1;\n";
+ # Since we strip "(\.\s*)\n" when we search a warning, strip it here as well
+ $header =~ s/(\.\s*)?$//;
+
+ my @toks = split( /(%l?[dxX]|%[ucp]|%(?:\.\d+)?[fs])/, $header );
+ if (@toks > 1) {
+ my $conlen = 0;
+ for my $i (0..$#toks){
+ if( $i % 2 ){
+ if( $toks[$i] eq '%c' ){
+ $toks[$i] = '.';
+ } elsif( $toks[$i] =~ /^%(?:d|u)$/ ){
+ $toks[$i] = '\d+';
+ } elsif( $toks[$i] =~ '^%(?:s|.*f)$' ){
+ $toks[$i] = $i == $#toks ? '.*' : '.*?';
+ } elsif( $toks[$i] =~ '%.(\d+)s' ){
+ $toks[$i] = ".{$1}";
+ } elsif( $toks[$i] =~ '^%l*([pxX])$' ){
+ $toks[$i] = $1 eq 'X' ? '[\dA-F]+' : '[\da-f]+';
+ }
+ } elsif( length( $toks[$i] ) ){
+ $toks[$i] = quotemeta $toks[$i];
+ $conlen += length( $toks[$i] );
+ }
+ }
+ my $lhs = join( '', @toks );
+ $lhs =~ s/(\\\s)+/\\s+/g; # Replace lit space with multi-space match
+ $transfmt{$header}{pat} =
+ " s\a^\\s*$lhs\\s*\a\Q$header\E\as\n\t&& return 1;\n";
+ $transfmt{$header}{len} = $conlen;
} else {
- $transmo .= " m{^\Q$header\E} && return 1;\n";
+ my $lhs = "\Q$header\E";
+ $lhs =~ s/(\\\s)+/\\s+/g; # Replace lit space with multi-space match
+ $transfmt{$header}{pat} =
+ " s\a^\\s*$lhs\\s*\a\Q$header\E\a\n\t && return 1;\n";
+ $transfmt{$header}{len} = length( $header );
}
- print STDERR "$WHOAMI: Duplicate entry: \"$header\"\n"
+ print STDERR __PACKAGE__.": Duplicate entry: \"$header\"\n"
if $msg{$header};
$msg{$header} = '';
+ $seen_body = 0;
}
die "No diagnostics?" unless %msg;
+ # Apply patterns in order of decreasing sum of lengths of fixed parts
+ # Seems the best way of hitting the right one.
+ for my $hdr ( sort { $transfmt{$b}{len} <=> $transfmt{$a}{len} }
+ keys %transfmt ){
+ $transmo .= $transfmt{$hdr}{pat};
+ }
$transmo .= " return 0;\n}\n";
print STDERR $transmo if $DEBUG;
eval $transmo;
shift;
$^W = 1; # yup, clobbered the global variable;
# tough, if you want diags, you want diags.
- return if $SIG{__WARN__} eq \&warn_trap;
+ return if defined $SIG{__WARN__} && ($SIG{__WARN__} eq \&warn_trap);
for (@_) {
$PRETTY++;
next;
};
+ # matches trace and traceonly for legacy doc mixup reasons
+ /^-t(race(only)?)?$/ && do {
+ $TRACEONLY++;
+ next;
+ };
+ /^-w(arntrace)?$/ && do {
+ $WARNTRACE++;
+ next;
+ };
warn "Unknown flag: $_";
}
sub warn_trap {
my $warning = $_[0];
- if (caller eq $WHOAMI or !splainthis($warning)) {
- print STDERR $warning;
+ if (caller eq __PACKAGE__ or !splainthis($warning)) {
+ if ($WARNTRACE) {
+ print STDERR Carp::longmess($warning);
+ } else {
+ print STDERR $warning;
+ }
}
- &$oldwarn if defined $oldwarn and $oldwarn and $oldwarn ne \&warn_trap;
+ goto &$oldwarn if defined $oldwarn and $oldwarn and $oldwarn ne \&warn_trap;
};
sub death_trap {
# want to explain the exception because it's going to get caught.
my $in_eval = 0;
my $i = 0;
- while (1) {
- my $caller = (caller($i++))[3] or last;
+ while (my $caller = (caller($i++))[3]) {
if ($caller eq '(eval)') {
$in_eval = 1;
last;
}
splainthis($exception) unless $in_eval;
- if (caller eq $WHOAMI) { print STDERR "INTERNAL EXCEPTION: $exception"; }
+ if (caller eq __PACKAGE__) {
+ print STDERR "INTERNAL EXCEPTION: $exception";
+ }
&$olddie if defined $olddie and $olddie and $olddie ne \&death_trap;
+ return if $in_eval;
+
# We don't want to unset these if we're coming from an eval because
- # then we've turned off diagnostics. (Actually what does this next
- # line do? -PSeibel)
- $SIG{__DIE__} = $SIG{__WARN__} = '' unless $in_eval;
- local($Carp::CarpLevel) = 1;
- confess "Uncaught exception from user code:\n\t$exception";
+ # then we've turned off diagnostics.
+
+ # Switch off our die/warn handlers so we don't wind up in our own
+ # traps.
+ $SIG{__DIE__} = $SIG{__WARN__} = '';
+
+ $exception =~ s/\n(?=.)/\n\t/gas;
+
+ die Carp::longmess("__diagnostics__")
+ =~ s/^__diagnostics__.*?line \d+\.?\n/
+ "Uncaught exception from user code:\n\t$exception"
+ /re;
# up we go; where we stop, nobody knows, but i think we die now
# but i'm deeply afraid of the &$olddie guy reraising and us getting
# into an indirect recursion loop
my $count;
my $wantspace;
sub splainthis {
- local $_ = shift;
+ return 0 if $TRACEONLY;
+ for (my $tmp = shift) {
local $\;
+ local $!;
### &finish_compilation unless %msg;
- s/\.?\n+$//;
+ s/(\.\s*)?\n+$//;
my $orig = $_;
# return unless defined;
+
+ # get rid of the where-are-we-in-input part
s/, <.*?> (?:line|chunk).*$//;
- my $real = s/(.*?) at .*? (?:line|chunk) \d+.*/$1/;
+
+ # Discard 1st " at <file> line <no>" and all text beyond
+ # but be aware of messages containing " at this-or-that"
+ my $real = 0;
+ my @secs = split( / at / );
+ return unless @secs;
+ $_ = $secs[0];
+ for my $i ( 1..$#secs ){
+ if( $secs[$i] =~ /.+? (?:line|chunk) \d+/ ){
+ $real = 1;
+ last;
+ } else {
+ $_ .= ' at ' . $secs[$i];
+ }
+ }
+
+ # remove parenthesis occurring at the end of some messages
s/^\((.*)\)$/$1/;
+
if ($exact_duplicate{$orig}++) {
return &transmo;
- }
- else {
+ } else {
return 0 unless &transmo;
}
- $orig = shorten($orig);
+
+ my $short = shorten($orig);
if ($old_diag{$_}) {
autodescribe();
- print THITHER "$orig (#$old_diag{$_})\n";
+ print THITHER "$short (#$old_diag{$_})\n";
$wantspace = 1;
+ } elsif (!$msg{$_} && $orig =~ /\n./s) {
+ # A multiline message, like "Attempt to reload /
+ # Compilation failed"
+ my $found;
+ for (split /^/, $orig) {
+ splainthis($_) and $found = 1;
+ }
+ return $found;
} else {
autodescribe();
$old_diag{$_} = ++$count;
print THITHER "\n" if $wantspace;
$wantspace = 0;
- print THITHER "$orig (#$old_diag{$_})\n";
+ print THITHER "$short (#$old_diag{$_})\n";
if ($msg{$_}) {
print THITHER $msg{$_};
} else {
}
}
return 1;
+ }
}
sub autodescribe {