Current File : C:/xampp/perl/vendor/lib/DBIx/Class/ResultSource/RowParser/Util.pm
package # hide from the pauses
DBIx::Class::ResultSource::RowParser::Util;
use strict;
use warnings;
use List::Util 'first';
use DBIx::Class::_Util 'perlstring';
use constant HAS_DOR => ( $] < 5.010 ? 0 : 1 );
use base 'Exporter';
our @EXPORT_OK = qw(
assemble_simple_parser
assemble_collapsing_parser
);
# working title - we are hoping to extract this eventually...
our $null_branch_class = 'DBIx::ResultParser::RelatedNullBranch';
sub __wrap_in_strictured_scope {
" { use strict; use warnings; use warnings FATAL => 'uninitialized';\n$_[0]\n }"
}
sub assemble_simple_parser {
#my ($args) = @_;
# the non-collapsing assembler is easy
# FIXME SUBOPTIMAL there could be a yet faster way to do things here, but
# need to try an actual implementation and benchmark it:
#
# <timbunce_> First setup the nested data structure you want for each row
# Then call bind_col() to alias the row fields into the right place in
# the data structure, then to fetch the data do:
# push @rows, dclone($row_data_struct) while ($sth->fetchrow);
#
my $parser_src = sprintf('$_ = %s for @{$_[0]}', __visit_infmap_simple($_[0]) );
# change the quoted placeholders to unquoted alias-references
$parser_src =~ s/ \' \xFF__VALPOS__(\d+)__\xFF \' /"\$_->[$1]"/gex;
__wrap_in_strictured_scope($parser_src);
}
# the simple non-collapsing nested structure recursor
sub __visit_infmap_simple {
my $args = shift;
my $my_cols = {};
my $rel_cols;
for (keys %{$args->{val_index}}) {
if ($_ =~ /^ ([^\.]+) \. (.+) /x) {
$rel_cols->{$1}{$2} = $args->{val_index}{$_};
}
else {
$my_cols->{$_} = $args->{val_index}{$_};
}
}
my @relperl;
for my $rel (sort keys %$rel_cols) {
my $rel_struct = __visit_infmap_simple({ %$args,
val_index => $rel_cols->{$rel},
});
if (keys %$my_cols) {
my $branch_null_checks = join ' && ', map
{ "( ! defined '\xFF__VALPOS__${_}__\xFF' )" }
sort { $a <=> $b } values %{$rel_cols->{$rel}}
;
if ($args->{prune_null_branches}) {
$rel_struct = sprintf ( '( (%s) ? undef : %s )',
$branch_null_checks,
$rel_struct,
);
}
else {
$rel_struct = sprintf ( '( (%s) ? bless( (%s), %s ) : %s )',
$branch_null_checks,
$rel_struct,
perlstring($null_branch_class),
$rel_struct,
);
}
}
push @relperl, sprintf '( %s => %s )',
perlstring($rel),
$rel_struct,
;
}
my $me_struct;
$me_struct = __result_struct_to_source($my_cols) if keys %$my_cols;
if ($args->{hri_style}) {
$me_struct =~ s/^ \s* \{ | \} \s* $//gx
if $me_struct;
return sprintf '{ %s }', join (', ', $me_struct||(), @relperl);
}
else {
return sprintf '[%s]', join (',',
$me_struct || 'undef',
@relperl ? sprintf ('{ %s }', join (',', @relperl)) : (),
);
}
}
sub assemble_collapsing_parser {
my $args = shift;
# it may get unset further down
my $no_rowid_container = $args->{prune_null_branches};
my ($top_node_key, $top_node_key_assembler);
if (scalar @{$args->{collapse_map}{-identifying_columns}}) {
$top_node_key = join ('', map
{ "{'\xFF__IDVALPOS__${_}__\xFF'}" }
@{$args->{collapse_map}{-identifying_columns}}
);
}
elsif( my @variants = @{$args->{collapse_map}{-identifying_columns_variants}} ) {
my @path_parts = map { sprintf
"( ( defined '\xFF__VALPOS__%d__\xFF' ) && (join qq(\xFF), '', %s, '') )",
$_->[0], # checking just first is enough - one ID defined, all defined
( join ', ', map { "'\xFF__VALPOS__${_}__\xFF'" } @$_ ),
} @variants;
my $virtual_column_idx = (scalar keys %{$args->{val_index}} ) + 1;
$top_node_key = "{'\xFF__IDVALPOS__${virtual_column_idx}__\xFF'}";
$top_node_key_assembler = sprintf "'\xFF__IDVALPOS__%d__\xFF' = (%s);",
$virtual_column_idx,
"\n" . join( "\n or\n", @path_parts, qq{"\0\$rows_pos\0"} )
;
$args->{collapse_map} = {
%{$args->{collapse_map}},
-custom_node_key => $top_node_key,
};
$no_rowid_container = 0;
}
else {
die('Unexpected collapse map contents');
}
my ($data_assemblers, $stats) = __visit_infmap_collapse ($args);
my @idcol_args = $no_rowid_container ? ('', '') : (
', %cur_row_ids', # only declare the variable if we'll use it
join ("\n", map {
my $quoted_null_val = qq( "\0NULL\xFF\${rows_pos}\xFF${_}\0" );
qq(\$cur_row_ids{$_} = ) . (
# in case we prune - we will never hit these undefs
$args->{prune_null_branches} ? qq( \$cur_row_data->[$_]; )
: HAS_DOR ? qq( \$cur_row_data->[$_] // $quoted_null_val; )
: qq( defined(\$cur_row_data->[$_]) ? \$cur_row_data->[$_] : $quoted_null_val; )
)
} sort { $a <=> $b } keys %{ $stats->{idcols_seen} } ),
);
my $parser_src = sprintf (<<'EOS', @idcol_args, $top_node_key_assembler||'', $top_node_key, join( "\n", @{$data_assemblers||[]} ) );
### BEGIN LITERAL STRING EVAL
my $rows_pos = 0;
my ($result_pos, @collapse_idx, $cur_row_data %1$s);
# this loop is a bit arcane - the rationale is that the passed in
# $_[0] will either have only one row (->next) or will have all
# rows already pulled in (->all and/or unordered). Given that the
# result can be rather large - we reuse the same already allocated
# array, since the collapsed prefetch is smaller by definition.
# At the end we cut the leftovers away and move on.
while ($cur_row_data = (
( $rows_pos >= 0 and $_[0][$rows_pos++] )
or
( $_[1] and $rows_pos = -1 and $_[1]->() )
) ) {
# this code exists only when we are using a cur_row_ids
# furthermore the undef checks may or may not be there
# depending on whether we prune or not
#
# due to left joins some of the ids may be NULL/undef, and
# won't play well when used as hash lookups
# we also need to differentiate NULLs on per-row/per-col basis
# (otherwise folding of optional 1:1s will be greatly confused
%2$s
# in the case of an underdefined root - calculate the virtual id (otherwise no code at all)
%3$s
# if we were supplied a coderef - we are collapsing lazily (the set
# is ordered properly)
# as long as we have a result already and the next result is new we
# return the pre-read data and bail
$_[1] and $result_pos and ! $collapse_idx[0]%4$s and (unshift @{$_[2]}, $cur_row_data) and last;
# the rel assemblers
%5$s
}
$#{$_[0]} = $result_pos - 1; # truncate the passed in array to where we filled it with results
### END LITERAL STRING EVAL
EOS
# !!! note - different var than the one above
# change the quoted placeholders to unquoted alias-references
$parser_src =~ s/ \' \xFF__VALPOS__(\d+)__\xFF \' /"\$cur_row_data->[$1]"/gex;
$parser_src =~ s/
\' \xFF__IDVALPOS__(\d+)__\xFF \'
/
$no_rowid_container ? "\$cur_row_data->[$1]" : "\$cur_row_ids{$1}"
/gex;
__wrap_in_strictured_scope($parser_src);
}
# the collapsing nested structure recursor
sub __visit_infmap_collapse {
my $args = {%{ shift() }};
my $cur_node_idx = ${ $args->{-node_idx_counter} ||= \do { my $x = 0} }++;
my ($my_cols, $rel_cols) = {};
for ( keys %{$args->{val_index}} ) {
if ($_ =~ /^ ([^\.]+) \. (.+) /x) {
$rel_cols->{$1}{$2} = $args->{val_index}{$_};
}
else {
$my_cols->{$_} = $args->{val_index}{$_};
}
}
if ($args->{hri_style}) {
delete $my_cols->{$_} for grep { $rel_cols->{$_} } keys %$my_cols;
}
my $me_struct;
$me_struct = __result_struct_to_source($my_cols) if keys %$my_cols;
$me_struct = sprintf( '[ %s ]', $me_struct||'' )
unless $args->{hri_style};
my $node_key = $args->{collapse_map}->{-custom_node_key} || join ('', map
{ "{'\xFF__IDVALPOS__${_}__\xFF'}" }
@{$args->{collapse_map}->{-identifying_columns}}
);
my $node_idx_slot = sprintf '$collapse_idx[%d]%s', $cur_node_idx, $node_key;
my @src;
if ($cur_node_idx == 0) {
push @src, sprintf( '%s %s $_[0][$result_pos++] = %s;',
$node_idx_slot,
(HAS_DOR ? '//=' : '||='),
$me_struct || '{}',
);
}
else {
my $parent_attach_slot = sprintf( '$collapse_idx[%d]%s%s{%s}',
@{$args}{qw/-parent_node_idx -parent_node_key/},
$args->{hri_style} ? '' : '[1]',
perlstring($args->{-node_rel_name}),
);
if ($args->{collapse_map}->{-is_single}) {
push @src, sprintf ( '%s %s %s%s;',
$parent_attach_slot,
(HAS_DOR ? '//=' : '||='),
$node_idx_slot,
$me_struct ? " = $me_struct" : '',
);
}
else {
push @src, sprintf('(! %s) and push @{%s}, %s%s;',
$node_idx_slot,
$parent_attach_slot,
$node_idx_slot,
$me_struct ? " = $me_struct" : '',
);
}
}
my $known_present_ids = { map { $_ => 1 } @{$args->{collapse_map}{-identifying_columns}} };
my ($stats, $rel_src);
for my $rel (sort keys %$rel_cols) {
my $relinfo = $args->{collapse_map}{$rel};
($rel_src, $stats->{$rel}) = __visit_infmap_collapse({ %$args,
val_index => $rel_cols->{$rel},
collapse_map => $relinfo,
-parent_node_idx => $cur_node_idx,
-parent_node_key => $node_key,
-node_rel_name => $rel,
});
my $rel_src_pos = $#src + 1;
push @src, @$rel_src;
if (
$relinfo->{-is_optional}
and
defined ( my $first_distinct_child_idcol = first
{ ! $known_present_ids->{$_} }
@{$relinfo->{-identifying_columns}}
)
) {
if ($args->{prune_null_branches}) {
# start of wrap of the entire chain in a conditional
splice @src, $rel_src_pos, 0, sprintf "( ! defined %s )\n ? %s%s{%s} = %s\n : do {",
"'\xFF__VALPOS__${first_distinct_child_idcol}__\xFF'",
$node_idx_slot,
$args->{hri_style} ? '' : '[1]',
perlstring($rel),
($args->{hri_style} && $relinfo->{-is_single}) ? 'undef' : '[]'
;
# end of wrap
push @src, '};'
}
else {
splice @src, $rel_src_pos + 1, 0, sprintf ( '(defined %s) or bless (%s[1]{%s}, %s);',
"'\xFF__VALPOS__${first_distinct_child_idcol}__\xFF'",
$node_idx_slot,
perlstring($rel),
perlstring($null_branch_class),
);
}
}
}
return (
\@src,
{
idcols_seen => {
( map { %{ $_->{idcols_seen} } } values %$stats ),
( map { $_ => 1 } @{$args->{collapse_map}->{-identifying_columns}} ),
}
}
);
}
sub __result_struct_to_source {
sprintf( '{ %s }', join (', ', map
{ sprintf "%s => '\xFF__VALPOS__%d__\xFF'", perlstring($_), $_[0]{$_} }
sort keys %{$_[0]}
));
}
1;
Mini Shell