X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=t%2Fresultset%2Frowparser_internals.t;h=5818248b1e90e16a6c103f4432341be08ac2ebf4;hb=908c46a247ef2d3f471f6d24ec16e90080354593;hp=c7d8ac8e21fb01ff0ea0c09f31e68e8da7a8453c;hpb=aa1d8a8751baf1e4c06b43f38ff9e02cdea51e6a;p=dbsrgits%2FDBIx-Class.git

diff --git a/t/resultset/rowparser_internals.t b/t/resultset/rowparser_internals.t
index c7d8ac8..5818248 100644
--- a/t/resultset/rowparser_internals.t
+++ b/t/resultset/rowparser_internals.t
@@ -5,6 +5,7 @@ use Test::More;
 use lib qw(t/lib);
 use DBICTest;
 use B::Deparse;
+use DBIx::Class::_Util 'perlstring';
 
 # globally set for the rest of test
 # the rowparser maker does not order its hashes by default for the miniscule
@@ -21,9 +22,9 @@ my $infmap = [qw/
 /];
 
 is_same_src (
-  $schema->source ('CD')->_mk_row_parser({
+  ($schema->source ('CD')->_mk_row_parser({
     inflate_map => $infmap,
-  }),
+  }))[0],
   '$_ = [
     { year => $_->[1] },
     { single_track => ( ! defined( $_->[0]) )
@@ -60,9 +61,9 @@ $infmap = [qw/
 /];
 
 is_same_src (
-  $schema->source ('CD')->_mk_row_parser({
+  ($schema->source ('CD')->_mk_row_parser({
     inflate_map => $infmap,
-  }),
+  }))[0],
   '$_ = [
     { artist => $_->[5], title => $_->[4], year => $_->[2] },
     {
@@ -137,10 +138,47 @@ is_same_src (
 );
 
 is_same_src (
-  $schema->source ('CD')->_mk_row_parser({
+  ($schema->source ('CD')->_mk_row_parser({
+    prune_null_branches => 1,
+    inflate_map => $infmap,
+  }))[0],
+  '$_ = [
+    { artist => $_->[5], title => $_->[4], year => $_->[2] },
+    {
+      single_track => ( (! defined $_->[0] ) && (! defined $_->[1]) && (! defined $_->[3] ) ) ? undef : [
+        undef,
+        {
+          cd => [
+            undef,
+            {
+              artist => [
+                { artistid => $_->[1] },
+                {
+                  cds => ( (! defined $_->[0] ) && ( ! defined $_->[3] ) ) ? undef : [
+                    { cdid => $_->[3] },
+                    {
+                      tracks => ( ! defined $_->[0] ) ? undef : [
+                        { title => $_->[0] },
+                      ]
+                    }
+                  ]
+                }
+              ]
+            }
+          ]
+        }
+      ]
+    }
+  ] for @{$_[0]}',
+  '1:1 descending non-collapsing pruning parser terminating with chained 1:M:M',
+);
+
+is_same_src (
+  ($schema->source ('CD')->_mk_row_parser({
     hri_style => 1,
+    prune_null_branches => 1,
     inflate_map => $infmap,
-  }),
+  }))[0],
   '$_ = {
       artist => $_->[5], title => $_->[4], year => $_->[2],
 
@@ -206,53 +244,70 @@ is_deeply (
 );
 
 is_same_src (
-  $schema->source ('CD')->_mk_row_parser({
+  ($schema->source ('CD')->_mk_row_parser({
     inflate_map => $infmap,
     collapse => 1,
-  }),
+  }))[0],
   ' my $rows_pos = 0;
     my ($result_pos, @collapse_idx, $cur_row_data, %cur_row_ids);
 
     while ($cur_row_data = (
-      ( $rows_pos >= 0 and $_[0][$rows_pos++] ) or do { $rows_pos = -1; undef } )
-        ||
+      (
+        $rows_pos >= 0
+          and
+        (
+          $_[0][$rows_pos++]
+            or
+          ( ($rows_pos = -1), undef )
+        )
+      )
+        or
       ( $_[1] and $_[1]->() )
-    ) {
+    ) ) {
 
-      $cur_row_ids{$_} = defined $cur_row_data->[$_] ? $cur_row_data->[$_] : "\0NULL\xFF$rows_pos\xFF$_\0"
-        for (0, 1, 3, 4, 5);
+      ( @cur_row_ids{0,1,3,4,5} = (
+        ( $cur_row_data->[0] // "\0NULL\xFF$rows_pos\xFF0\0" ),
+        ( $cur_row_data->[1] // "\0NULL\xFF$rows_pos\xFF1\0" ),
+        ( $cur_row_data->[3] // "\0NULL\xFF$rows_pos\xFF3\0" ),
+        ( $cur_row_data->[4] // "\0NULL\xFF$rows_pos\xFF4\0" ),
+        ( $cur_row_data->[5] // "\0NULL\xFF$rows_pos\xFF5\0" ),
+      ) ),
 
       # a present cref in $_[1] implies lazy prefetch, implies a supplied stash in $_[2]
-      $_[1] and $result_pos and ! $collapse_idx[0]{$cur_row_ids{4}}{$cur_row_ids{5}} and (unshift @{$_[2]}, $cur_row_data) and last;
+      ( $_[1] and $result_pos and ! $collapse_idx[0]{$cur_row_ids{4}}{$cur_row_ids{5}} and (unshift @{$_[2]}, $cur_row_data) and last ),
 
       # the rowdata itself for root node
-      $collapse_idx[0]{$cur_row_ids{4}}{$cur_row_ids{5}} ||= $_[0][$result_pos++] = [{ artist => $cur_row_data->[5], title => $cur_row_data->[4], year => $cur_row_data->[2] }];
+      ( $collapse_idx[0]{$cur_row_ids{4}}{$cur_row_ids{5}} //= $_[0][$result_pos++] = [{ artist => $cur_row_data->[5], title => $cur_row_data->[4], year => $cur_row_data->[2] }] ),
 
       # prefetch data of single_track (placed in root)
-      $collapse_idx[0]{$cur_row_ids{4}}{$cur_row_ids{5}}[1]{single_track} ||= $collapse_idx[1]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}} = [];
-      defined($cur_row_data->[1]) or bless( $collapse_idx[0]{$cur_row_ids{4}}{$cur_row_ids{5}}[1]{single_track}, __NBC__ );
+      ( $collapse_idx[0]{$cur_row_ids{4}}{$cur_row_ids{5}}[1]{single_track} //= $collapse_idx[1]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}} = [] ),
+      ( defined($cur_row_data->[1]) or bless( $collapse_idx[0]{$cur_row_ids{4}}{$cur_row_ids{5}}[1]{single_track}, __NBC__ ) ),
 
       # prefetch data of cd (placed in single_track)
-      $collapse_idx[1]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}}[1]{cd} ||= $collapse_idx[2]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}} = [];
+      ( $collapse_idx[1]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}}[1]{cd} //= $collapse_idx[2]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}} = [] ),
 
       # prefetch data of artist ( placed in single_track->cd)
-      $collapse_idx[2]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}}[1]{artist} ||= $collapse_idx[3]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}} = [{ artistid => $cur_row_data->[1] }];
+      ( $collapse_idx[2]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}}[1]{artist} //= $collapse_idx[3]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}} = [{ artistid => $cur_row_data->[1] }] ),
 
       # prefetch data of cds (if available)
-      (! $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}} )
-        and
-      push @{$collapse_idx[3]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}}[1]{cds}}, (
-        $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}} = [{ cdid => $cur_row_data->[3] }]
-      );
-      defined($cur_row_data->[3]) or bless( $collapse_idx[3]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}}[1]{cds}, __NBC__ );
+      (
+        (! $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}} )
+          and
+        push @{$collapse_idx[3]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}}[1]{cds}}, (
+          $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}} = [{ cdid => $cur_row_data->[3] }]
+        )
+      ),
+      ( defined($cur_row_data->[3]) or bless( $collapse_idx[3]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}}[1]{cds}, __NBC__ ) ),
 
       # prefetch data of tracks (if available)
-      (! $collapse_idx[5]{$cur_row_ids{0}}{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}} )
-        and
-      push @{$collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}}[1]{tracks}}, (
-        $collapse_idx[5]{$cur_row_ids{0}}{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}} = [{ title => $cur_row_data->[0] }]
-      );
-      defined($cur_row_data->[0]) or bless( $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}}[1]{tracks}, __NBC__ );
+      (
+        (! $collapse_idx[5]{$cur_row_ids{0}}{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}} )
+          and
+        push @{$collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}}[1]{tracks}}, (
+          $collapse_idx[5]{$cur_row_ids{0}}{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}} = [{ title => $cur_row_data->[0] }]
+        )
+      ),
+      ( defined($cur_row_data->[0]) or bless( $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}}[1]{tracks}, __NBC__ ) ),
 
     }
     $#{$_[0]} = $result_pos - 1;
@@ -261,56 +316,71 @@ is_same_src (
 );
 
 is_same_src (
-  $schema->source ('CD')->_mk_row_parser({
+  ($schema->source ('CD')->_mk_row_parser({
     inflate_map => $infmap,
     collapse => 1,
     hri_style => 1,
-  }),
+    prune_null_branches => 1,
+  }))[0],
   ' my $rows_pos = 0;
-    my ($result_pos, @collapse_idx, $cur_row_data);
+    my ($result_pos, @collapse_idx, $cur_row_data, %cur_row_ids);
 
     while ($cur_row_data = (
-      ( $rows_pos >= 0 and $_[0][$rows_pos++] ) or do { $rows_pos = -1; undef } )
-        ||
+      (
+        $rows_pos >= 0
+          and
+        (
+          $_[0][$rows_pos++]
+            or
+          ( ($rows_pos = -1), undef )
+        )
+      )
+        or
       ( $_[1] and $_[1]->() )
-    ) {
+    ) ) {
+
+      ( @cur_row_ids{0, 1, 3, 4, 5} = @{$cur_row_data}[0, 1, 3, 4, 5] ),
 
       # a present cref in $_[1] implies lazy prefetch, implies a supplied stash in $_[2]
-      $_[1] and $result_pos and ! $collapse_idx[0]{$cur_row_data->[4]}{$cur_row_data->[5]} and (unshift @{$_[2]}, $cur_row_data) and last;
+      ( $_[1] and $result_pos and ! $collapse_idx[0]{$cur_row_ids{4}}{$cur_row_ids{5}} and (unshift @{$_[2]}, $cur_row_data) and last ),
 
       # the rowdata itself for root node
-      $collapse_idx[0]{$cur_row_data->[4]}{$cur_row_data->[5]} ||= $_[0][$result_pos++] = { artist => $cur_row_data->[5], title => $cur_row_data->[4], year => $cur_row_data->[2] };
+      ( $collapse_idx[0]{$cur_row_ids{4}}{$cur_row_ids{5}} //= $_[0][$result_pos++] = { artist => $cur_row_data->[5], title => $cur_row_data->[4], year => $cur_row_data->[2] } ),
 
       # prefetch data of single_track (placed in root)
-      (! defined($cur_row_data->[1]) ) ? $collapse_idx[0]{$cur_row_data->[4]}{$cur_row_data->[5]}{single_track} = undef : do {
-        $collapse_idx[0]{$cur_row_data->[4]}{$cur_row_data->[5]}{single_track} ||= $collapse_idx[1]{$cur_row_data->[1]}{$cur_row_data->[4]}{$cur_row_data->[5]};
+      ( (! defined($cur_row_data->[1]) ) ? $collapse_idx[0]{$cur_row_ids{4}}{$cur_row_ids{5}}{single_track} = undef : do {
+        ( $collapse_idx[0]{$cur_row_ids{4}}{$cur_row_ids{5}}{single_track} //= $collapse_idx[1]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}} ),
 
         # prefetch data of cd (placed in single_track)
-        $collapse_idx[1]{$cur_row_data->[1]}{$cur_row_data->[4]}{$cur_row_data->[5]}{cd} ||= $collapse_idx[2]{$cur_row_data->[1]}{$cur_row_data->[4]}{$cur_row_data->[5]};
+        ( $collapse_idx[1]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}}{cd} //= $collapse_idx[2]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}} ),
 
         # prefetch data of artist ( placed in single_track->cd)
-        $collapse_idx[2]{$cur_row_data->[1]}{$cur_row_data->[4]}{$cur_row_data->[5]}{artist} ||= $collapse_idx[3]{$cur_row_data->[1]}{$cur_row_data->[4]}{$cur_row_data->[5]} = { artistid => $cur_row_data->[1] };
+        ( $collapse_idx[2]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}}{artist} //= $collapse_idx[3]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}} = { artistid => $cur_row_data->[1] } ),
 
         # prefetch data of cds (if available)
-        (! defined $cur_row_data->[3] ) ? $collapse_idx[3]{$cur_row_data->[1]}{$cur_row_data->[4]}{$cur_row_data->[5]}{cds} = [] : do {
+        ( (! defined $cur_row_data->[3] ) ? $collapse_idx[3]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}}{cds} = [] : do {
 
-          (! $collapse_idx[4]{$cur_row_data->[1]}{$cur_row_data->[3]}{$cur_row_data->[4]}{$cur_row_data->[5]} )
-            and
-          push @{$collapse_idx[3]{$cur_row_data->[1]}{$cur_row_data->[4]}{$cur_row_data->[5]}{cds}}, (
-            $collapse_idx[4]{$cur_row_data->[1]}{$cur_row_data->[3]}{$cur_row_data->[4]}{$cur_row_data->[5]} = { cdid => $cur_row_data->[3] }
-          );
+          (
+            (! $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}} )
+              and
+            push @{$collapse_idx[3]{$cur_row_ids{1}}{$cur_row_ids{4}}{$cur_row_ids{5}}{cds}}, (
+              $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}} = { cdid => $cur_row_data->[3] }
+            )
+          ),
 
           # prefetch data of tracks (if available)
-          ( ! defined $cur_row_data->[0] ) ? $collapse_idx[4]{$cur_row_data->[1]}{$cur_row_data->[3]}{$cur_row_data->[4]}{$cur_row_data->[5]}{tracks} = [] : do {
-
-            (! $collapse_idx[5]{$cur_row_data->[0]}{$cur_row_data->[1]}{$cur_row_data->[3]}{$cur_row_data->[4]}{$cur_row_data->[5]} )
-              and
-            push @{$collapse_idx[4]{$cur_row_data->[1]}{$cur_row_data->[3]}{$cur_row_data->[4]}{$cur_row_data->[5]}{tracks}}, (
-              $collapse_idx[5]{$cur_row_data->[0]}{$cur_row_data->[1]}{$cur_row_data->[3]}{$cur_row_data->[4]}{$cur_row_data->[5]} = { title => $cur_row_data->[0] }
-            );
-          };
-        };
-      };
+          (( ! defined $cur_row_data->[0] ) ? $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}}{tracks} = [] : do {
+
+            (
+              (! $collapse_idx[5]{$cur_row_ids{0}}{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}} )
+                and
+              push @{$collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}}{tracks}}, (
+                $collapse_idx[5]{$cur_row_ids{0}}{$cur_row_ids{1}}{$cur_row_ids{3}}{$cur_row_ids{4}}{$cur_row_ids{5}} = { title => $cur_row_data->[0] }
+              )
+            ),
+          } ),
+        } ),
+      } ),
     }
     $#{$_[0]} = $result_pos - 1;
   ',
@@ -379,60 +449,82 @@ is_deeply (
 );
 
 is_same_src (
-  $schema->source ('CD')->_mk_row_parser({
+  ($schema->source ('CD')->_mk_row_parser({
     inflate_map => $infmap,
     collapse => 1,
-  }),
+  }))[0],
   ' my $rows_pos = 0;
     my ($result_pos, @collapse_idx, $cur_row_data, %cur_row_ids);
 
     while ($cur_row_data = (
-      ( $rows_pos >= 0 and $_[0][$rows_pos++] ) or do { $rows_pos = -1; undef } )
-        ||
+      (
+        $rows_pos >= 0
+          and
+        (
+          $_[0][$rows_pos++]
+            or
+          ( ($rows_pos = -1), undef )
+        )
+      )
+        or
       ( $_[1] and $_[1]->() )
-    ) {
+    ) ) {
 
-      $cur_row_ids{$_} = defined $cur_row_data->[$_] ? $cur_row_data->[$_] : "\0NULL\xFF$rows_pos\xFF$_\0"
-        for (0, 1, 5, 6, 8, 10);
+      ( @cur_row_ids{0, 1, 5, 6, 8, 10} = (
+        $cur_row_data->[0] // "\0NULL\xFF$rows_pos\xFF0\0",
+        $cur_row_data->[1] // "\0NULL\xFF$rows_pos\xFF1\0",
+        $cur_row_data->[5] // "\0NULL\xFF$rows_pos\xFF5\0",
+        $cur_row_data->[6] // "\0NULL\xFF$rows_pos\xFF6\0",
+        $cur_row_data->[8] // "\0NULL\xFF$rows_pos\xFF8\0",
+        $cur_row_data->[10] // "\0NULL\xFF$rows_pos\xFF10\0",
+      ) ),
 
       # a present cref in $_[1] implies lazy prefetch, implies a supplied stash in $_[2]
-      $_[1] and $result_pos and ! $collapse_idx[0]{$cur_row_ids{1}} and (unshift @{$_[2]}, $cur_row_data) and last;
-
-      $collapse_idx[0]{$cur_row_ids{1}} ||= $_[0][$result_pos++] = [{ genreid => $cur_row_data->[4], latest_cd => $cur_row_data->[7], year => $cur_row_data->[3] }];
-
-      $collapse_idx[0]{$cur_row_ids{1}}[1]{existing_single_track} ||= $collapse_idx[1]{$cur_row_ids{1}} = [];
-      $collapse_idx[1]{$cur_row_ids{1}}[1]{cd} ||= $collapse_idx[2]{$cur_row_ids{1}} = [];
-      $collapse_idx[2]{$cur_row_ids{1}}[1]{artist} ||= $collapse_idx[3]{$cur_row_ids{1}} = [{ artistid => $cur_row_data->[1] }];
-
-      (! $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{6}} )
-        and
-      push @{ $collapse_idx[3]{$cur_row_ids{1}}[1]{cds} }, (
-        $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{6}} = [{ cdid => $cur_row_data->[6], genreid => $cur_row_data->[9], year => $cur_row_data->[2] }]
-      );
-      defined($cur_row_data->[6]) or bless( $collapse_idx[3]{$cur_row_ids{1}}[1]{cds}, __NBC__ );
-
-      (! $collapse_idx[5]{$cur_row_ids{1}}{$cur_row_ids{6}}{$cur_row_ids{8}} )
-        and
-      push @{ $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{6}}[1]{tracks} }, (
-        $collapse_idx[5]{$cur_row_ids{1}}{$cur_row_ids{6}}{$cur_row_ids{8}} = [{ title => $cur_row_data->[8] }]
-      );
-      defined($cur_row_data->[8]) or bless( $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{6}}[1]{tracks}, __NBC__ );
-
-      (! $collapse_idx[6]{$cur_row_ids{1}}{$cur_row_ids{5}} )
-        and
-      push @{ $collapse_idx[0]{$cur_row_ids{1}}[1]{tracks} }, (
-        $collapse_idx[6]{$cur_row_ids{1}}{$cur_row_ids{5}} = [{ title => $cur_row_data->[5] }]
-      );
-      defined($cur_row_data->[5]) or bless( $collapse_idx[0]{$cur_row_ids{1}}[1]{tracks}, __NBC__ );
-
-      $collapse_idx[6]{$cur_row_ids{1}}{$cur_row_ids{5}}[1]{lyrics} ||= $collapse_idx[7]{$cur_row_ids{1}}{$cur_row_ids{5}}{$cur_row_ids{10}} = [];
-      defined($cur_row_data->[10]) or bless( $collapse_idx[6]{$cur_row_ids{1}}{$cur_row_ids{5}}[1]{lyrics}, __NBC__ );
-
-      (! $collapse_idx[8]{$cur_row_ids{0}}{$cur_row_ids{1}}{$cur_row_ids{5}}{$cur_row_ids{10}} )
-        and
-      push @{ $collapse_idx[7]{$cur_row_ids{1}}{$cur_row_ids{5}}{$cur_row_ids{10}}[1]{existing_lyric_versions} }, (
-        $collapse_idx[8]{$cur_row_ids{0}}{$cur_row_ids{1}}{$cur_row_ids{5}}{$cur_row_ids{10}} = [{ lyric_id => $cur_row_data->[10], text => $cur_row_data->[0] }]
-      );
+      ( $_[1] and $result_pos and ! $collapse_idx[0]{$cur_row_ids{1}} and (unshift @{$_[2]}, $cur_row_data) and last ),
+
+      ( $collapse_idx[0]{$cur_row_ids{1}} //= $_[0][$result_pos++] = [{ genreid => $cur_row_data->[4], latest_cd => $cur_row_data->[7], year => $cur_row_data->[3] }] ),
+
+      ( $collapse_idx[0]{$cur_row_ids{1}}[1]{existing_single_track} //= $collapse_idx[1]{$cur_row_ids{1}} = [] ),
+      ( $collapse_idx[1]{$cur_row_ids{1}}[1]{cd} //= $collapse_idx[2]{$cur_row_ids{1}} = [] ),
+      ( $collapse_idx[2]{$cur_row_ids{1}}[1]{artist} //= $collapse_idx[3]{$cur_row_ids{1}} = [{ artistid => $cur_row_data->[1] }] ),
+
+      (
+        (! $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{6}} )
+          and
+        push @{ $collapse_idx[3]{$cur_row_ids{1}}[1]{cds} }, (
+          $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{6}} = [{ cdid => $cur_row_data->[6], genreid => $cur_row_data->[9], year => $cur_row_data->[2] }]
+        )
+      ),
+      ( defined($cur_row_data->[6]) or bless( $collapse_idx[3]{$cur_row_ids{1}}[1]{cds}, __NBC__ ) ),
+
+      (
+        (! $collapse_idx[5]{$cur_row_ids{1}}{$cur_row_ids{6}}{$cur_row_ids{8}} )
+          and
+        push @{ $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{6}}[1]{tracks} }, (
+          $collapse_idx[5]{$cur_row_ids{1}}{$cur_row_ids{6}}{$cur_row_ids{8}} = [{ title => $cur_row_data->[8] }]
+        )
+      ),
+      ( defined($cur_row_data->[8]) or bless( $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{6}}[1]{tracks}, __NBC__ ) ),
+
+      (
+        (! $collapse_idx[6]{$cur_row_ids{1}}{$cur_row_ids{5}} )
+          and
+        push @{ $collapse_idx[0]{$cur_row_ids{1}}[1]{tracks} }, (
+          $collapse_idx[6]{$cur_row_ids{1}}{$cur_row_ids{5}} = [{ title => $cur_row_data->[5] }]
+        )
+      ),
+      ( defined($cur_row_data->[5]) or bless( $collapse_idx[0]{$cur_row_ids{1}}[1]{tracks}, __NBC__ ) ),
+
+      ( $collapse_idx[6]{$cur_row_ids{1}}{$cur_row_ids{5}}[1]{lyrics} //= $collapse_idx[7]{$cur_row_ids{1}}{$cur_row_ids{5}}{$cur_row_ids{10}} = [] ),
+      ( defined($cur_row_data->[10]) or bless( $collapse_idx[6]{$cur_row_ids{1}}{$cur_row_ids{5}}[1]{lyrics}, __NBC__ ) ),
+
+      (
+        (! $collapse_idx[8]{$cur_row_ids{0}}{$cur_row_ids{1}}{$cur_row_ids{5}}{$cur_row_ids{10}} )
+          and
+        push @{ $collapse_idx[7]{$cur_row_ids{1}}{$cur_row_ids{5}}{$cur_row_ids{10}}[1]{existing_lyric_versions} }, (
+          $collapse_idx[8]{$cur_row_ids{0}}{$cur_row_ids{1}}{$cur_row_ids{5}}{$cur_row_ids{10}} = [{ lyric_id => $cur_row_data->[10], text => $cur_row_data->[0] }]
+        )
+      ),
     }
 
     $#{$_[0]} = $result_pos - 1;
@@ -441,65 +533,87 @@ is_same_src (
 );
 
 is_same_src (
-  $schema->source ('CD')->_mk_row_parser({
+  ($schema->source ('CD')->_mk_row_parser({
     inflate_map => $infmap,
     collapse => 1,
-  }),
+    prune_null_branches => 1,
+  }))[0],
   ' my $rows_pos = 0;
     my ($result_pos, @collapse_idx, $cur_row_data, %cur_row_ids);
 
     while ($cur_row_data = (
-      ( $rows_pos >= 0 and $_[0][$rows_pos++] ) or do { $rows_pos = -1; undef } )
-        ||
+      (
+        $rows_pos >= 0
+          and
+        (
+          $_[0][$rows_pos++]
+            or
+          ( ($rows_pos = -1), undef )
+        )
+      )
+        or
       ( $_[1] and $_[1]->() )
-    ) {
+    ) ) {
 
-      $cur_row_ids{$_} = defined $cur_row_data->[$_] ? $cur_row_data->[$_] : "\0NULL\xFF$rows_pos\xFF$_\0"
-        for (0, 1, 5, 6, 8, 10);
+      ( @cur_row_ids{( 0, 1, 5, 6, 8, 10 )} = @{$cur_row_data}[( 0, 1, 5, 6, 8, 10 )] ),
 
       # a present cref in $_[1] implies lazy prefetch, implies a supplied stash in $_[2]
-      $_[1] and $result_pos and ! $collapse_idx[0]{$cur_row_ids{1}} and (unshift @{$_[2]}, $cur_row_data) and last;
-
-      $collapse_idx[0]{$cur_row_ids{1}} ||= $_[0][$result_pos++] = [{ genreid => $cur_row_data->[4], latest_cd => $cur_row_data->[7], year => $cur_row_data->[3] }];
-
-      $collapse_idx[0]{$cur_row_ids{1}}[1]{existing_single_track} ||= $collapse_idx[1]{$cur_row_ids{1}} = [];
-      $collapse_idx[1]{$cur_row_ids{1}}[1]{cd} ||= $collapse_idx[2]{$cur_row_ids{1}} = [];
-      $collapse_idx[2]{$cur_row_ids{1}}[1]{artist} ||= $collapse_idx[3]{$cur_row_ids{1}} = [{ artistid => $cur_row_data->[1] }];
-
-      (! $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{6}} )
-        and
-      push @{ $collapse_idx[3]{$cur_row_ids{1}}[1]{cds} }, (
-        $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{6}} = [{ cdid => $cur_row_data->[6], genreid => $cur_row_data->[9], year => $cur_row_data->[2] }]
-      );
-      defined($cur_row_data->[6]) or bless( $collapse_idx[3]{$cur_row_ids{1}}[1]{cds}, __NBC__ );
-
-      (! $collapse_idx[5]{$cur_row_ids{1}}{$cur_row_ids{6}}{$cur_row_ids{8}} )
-        and
-      push @{ $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{6}}[1]{tracks} }, (
-        $collapse_idx[5]{$cur_row_ids{1}}{$cur_row_ids{6}}{$cur_row_ids{8}} = [{ title => $cur_row_data->[8] }]
-      );
-      defined($cur_row_data->[8]) or bless( $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{6}}[1]{tracks}, __NBC__ );
-
-      (! $collapse_idx[6]{$cur_row_ids{1}}{$cur_row_ids{5}} )
-        and
-      push @{ $collapse_idx[0]{$cur_row_ids{1}}[1]{tracks} }, (
-        $collapse_idx[6]{$cur_row_ids{1}}{$cur_row_ids{5}} = [{ title => $cur_row_data->[5] }]
-      );
-      defined($cur_row_data->[5]) or bless( $collapse_idx[0]{$cur_row_ids{1}}[1]{tracks}, __NBC__ );
-
-      $collapse_idx[6]{$cur_row_ids{1}}{$cur_row_ids{5}}[1]{lyrics} ||= $collapse_idx[7]{$cur_row_ids{1}}{$cur_row_ids{5}}{$cur_row_ids{10}} = [];
-      defined($cur_row_data->[10]) or bless( $collapse_idx[6]{$cur_row_ids{1}}{$cur_row_ids{5}}[1]{lyrics}, __NBC__ );
-
-      (! $collapse_idx[8]{$cur_row_ids{0}}{$cur_row_ids{1}}{$cur_row_ids{5}}{$cur_row_ids{10}} )
-        and
-      push @{ $collapse_idx[7]{$cur_row_ids{1}}{$cur_row_ids{5}}{$cur_row_ids{10}}[1]{existing_lyric_versions} }, (
-        $collapse_idx[8]{$cur_row_ids{0}}{$cur_row_ids{1}}{$cur_row_ids{5}}{$cur_row_ids{10}} = [{ lyric_id => $cur_row_data->[10], text => $cur_row_data->[0] }]
-      );
+      ( $_[1] and $result_pos and ! $collapse_idx[0]{$cur_row_ids{1}} and (unshift @{$_[2]}, $cur_row_data) and last ),
+
+      ( $collapse_idx[0]{$cur_row_ids{1}} //= $_[0][$result_pos++] = [{ genreid => $cur_row_data->[4], latest_cd => $cur_row_data->[7], year => $cur_row_data->[3] }] ),
+
+      ( $collapse_idx[0]{$cur_row_ids{1}}[1]{existing_single_track} //= $collapse_idx[1]{$cur_row_ids{1}} = [] ),
+      ( $collapse_idx[1]{$cur_row_ids{1}}[1]{cd} //= $collapse_idx[2]{$cur_row_ids{1}} = [] ),
+      ( $collapse_idx[2]{$cur_row_ids{1}}[1]{artist} //= $collapse_idx[3]{$cur_row_ids{1}} = [{ artistid => $cur_row_data->[1] }] ),
+
+      ( (! defined($cur_row_data->[6])) ? $collapse_idx[3]{$cur_row_ids{1}}[1]{cds} = [] : do {
+        (
+          (! $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{6}} )
+            and
+          push @{ $collapse_idx[3]{$cur_row_ids{1}}[1]{cds} }, (
+            $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{6}} = [{ cdid => $cur_row_data->[6], genreid => $cur_row_data->[9], year => $cur_row_data->[2] }]
+          )
+        ),
+
+        ( (! defined($cur_row_data->[8]) ) ? $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{6}}[1]{tracks} = [] : do {
+          (
+            (! $collapse_idx[5]{$cur_row_ids{1}}{$cur_row_ids{6}}{$cur_row_ids{8}} )
+              and
+            push @{ $collapse_idx[4]{$cur_row_ids{1}}{$cur_row_ids{6}}[1]{tracks} }, (
+              $collapse_idx[5]{$cur_row_ids{1}}{$cur_row_ids{6}}{$cur_row_ids{8}} = [{ title => $cur_row_data->[8] }]
+            )
+          ),
+        } ),
+      } ),
+
+      ( (! defined($cur_row_data->[5]) ) ? $collapse_idx[0]{$cur_row_ids{1}}[1]{tracks} = [] : do {
+
+        (
+          (! $collapse_idx[6]{$cur_row_ids{1}}{$cur_row_ids{5}} )
+            and
+          push @{ $collapse_idx[0]{$cur_row_ids{1}}[1]{tracks} }, (
+            $collapse_idx[6]{$cur_row_ids{1}}{$cur_row_ids{5}} = [{ title => $cur_row_data->[5] }]
+          )
+        ),
+
+        ( (! defined($cur_row_data->[10]) ) ? $collapse_idx[6]{$cur_row_ids{1}}{$cur_row_ids{5}}[1]{lyrics} = [] : do {
+
+          ( $collapse_idx[6]{$cur_row_ids{1}}{$cur_row_ids{5}}[1]{lyrics} //= $collapse_idx[7]{$cur_row_ids{1}}{$cur_row_ids{5}}{$cur_row_ids{10}} = [] ),
+
+          (
+            (! $collapse_idx[8]{$cur_row_ids{0}}{$cur_row_ids{1}}{$cur_row_ids{5}}{$cur_row_ids{10}} )
+              and
+            push @{ $collapse_idx[7]{$cur_row_ids{1}}{$cur_row_ids{5}}{$cur_row_ids{10}}[1]{existing_lyric_versions} }, (
+              $collapse_idx[8]{$cur_row_ids{0}}{$cur_row_ids{1}}{$cur_row_ids{5}}{$cur_row_ids{10}} = [{ lyric_id => $cur_row_data->[10], text => $cur_row_data->[0] }]
+            )
+          ),
+        } ),
+      } ),
     }
 
     $#{$_[0]} = $result_pos - 1;
   ',
-  'Multiple has_many on multiple branches with branch torture test',
+  'Multiple has_many on multiple branches with branch pruning torture test',
 );
 
 $infmap = [
@@ -551,63 +665,82 @@ is_deeply (
 );
 
 is_same_src (
-  $schema->source ('CD')->_mk_row_parser({
+  ($schema->source ('CD')->_mk_row_parser({
     inflate_map => $infmap,
     collapse => 1,
-  }),
+  }))[0],
   ' my $rows_pos = 0;
     my ($result_pos, @collapse_idx, $cur_row_data, %cur_row_ids);
 
     while ($cur_row_data = (
-      ( $rows_pos >= 0 and $_[0][$rows_pos++] ) or do { $rows_pos = -1; undef } )
-        ||
+      (
+        $rows_pos >= 0
+          and
+        (
+          $_[0][$rows_pos++]
+            or
+          ( ($rows_pos = -1), undef )
+        )
+      )
+        or
       ( $_[1] and $_[1]->() )
-    ) {
+    ) ) {
 
-      $cur_row_ids{$_} = defined $$cur_row_data[$_] ? $$cur_row_data[$_] : "\0NULL\xFF$rows_pos\xFF$_\0"
-        for (0, 2, 3, 4, 8);
+      ( @cur_row_ids{( 0, 2, 3, 4, 8 )} = (
+        $cur_row_data->[0] // "\0NULL\xFF$rows_pos\xFF0\0",
+        $cur_row_data->[2] // "\0NULL\xFF$rows_pos\xFF2\0",
+        $cur_row_data->[3] // "\0NULL\xFF$rows_pos\xFF3\0",
+        $cur_row_data->[4] // "\0NULL\xFF$rows_pos\xFF4\0",
+        $cur_row_data->[8] // "\0NULL\xFF$rows_pos\xFF8\0",
+      )),
 
       # cache expensive set of ops in a non-existent rowid slot
-      $cur_row_ids{10} = (
-        ( ( defined $cur_row_data->[0] ) && (join "\xFF", q{}, $cur_row_data->[0], q{} ))
+      ( $cur_row_ids{10} = (
+        ( ( defined $cur_row_data->[0] ) && (join "\xFF", q{}, $cur_row_ids{0}, q{} ))
           or
-        ( ( defined $cur_row_data->[2] ) && (join "\xFF", q{}, $cur_row_data->[2], q{} ))
+        ( ( defined $cur_row_data->[2] ) && (join "\xFF", q{}, $cur_row_ids{2}, q{} ))
           or
         "\0$rows_pos\0"
-      );
+      )),
 
       # a present cref in $_[1] implies lazy prefetch, implies a supplied stash in $_[2]
-      $_[1] and $result_pos and ! $collapse_idx[0]{$cur_row_ids{10}} and (unshift @{$_[2]}, $cur_row_data) and last;
+      ( $_[1] and $result_pos and ! $collapse_idx[0]{$cur_row_ids{10}} and (unshift @{$_[2]}, $cur_row_data) and last ),
 
-      $collapse_idx[0]{$cur_row_ids{10}} ||= $_[0][$result_pos++] = [{ year => $$cur_row_data[1] }];
+      ( $collapse_idx[0]{$cur_row_ids{10}} //= $_[0][$result_pos++] = [{ year => $$cur_row_data[1] }] ),
 
-      $collapse_idx[0]{$cur_row_ids{10}}[1]{single_track} ||= ($collapse_idx[1]{$cur_row_ids{0}} = [{ trackid => $cur_row_data->[0] }]);
-      defined($cur_row_data->[0]) or bless ( $collapse_idx[0]{$cur_row_ids{10}}[1]{single_track}, __NBC__ );
+      ( $collapse_idx[0]{$cur_row_ids{10}}[1]{single_track} //= ($collapse_idx[1]{$cur_row_ids{0}} = [{ trackid => $cur_row_data->[0] }]) ),
+      ( defined($cur_row_data->[0]) or bless ( $collapse_idx[0]{$cur_row_ids{10}}[1]{single_track}, __NBC__ ) ),
 
-      $collapse_idx[1]{$cur_row_ids{0}}[1]{cd} ||= $collapse_idx[2]{$cur_row_ids{0}} = [];
+      ( $collapse_idx[1]{$cur_row_ids{0}}[1]{cd} //= $collapse_idx[2]{$cur_row_ids{0}} = [] ),
 
-      $collapse_idx[2]{$cur_row_ids{0}}[1]{artist} ||= ($collapse_idx[3]{$cur_row_ids{0}} = [{ artistid => $cur_row_data->[6] }]);
+      ( $collapse_idx[2]{$cur_row_ids{0}}[1]{artist} //= ($collapse_idx[3]{$cur_row_ids{0}} = [{ artistid => $cur_row_data->[6] }]) ),
 
-      (! $collapse_idx[4]{$cur_row_ids{0}}{$cur_row_ids{4}} )
-        and
-      push @{$collapse_idx[3]{$cur_row_ids{0}}[1]{cds}}, (
+      (
+        (! $collapse_idx[4]{$cur_row_ids{0}}{$cur_row_ids{4}} )
+          and
+        push @{$collapse_idx[3]{$cur_row_ids{0}}[1]{cds}}, (
           $collapse_idx[4]{$cur_row_ids{0}}{$cur_row_ids{4}} = [{ cdid => $cur_row_data->[4], genreid => $cur_row_data->[7], year => $cur_row_data->[5] }]
-      );
-      defined($cur_row_data->[4]) or bless ( $collapse_idx[3]{$cur_row_ids{0}}[1]{cds}, __NBC__ );
-
-      (! $collapse_idx[5]{$cur_row_ids{0}}{$cur_row_ids{4}}{$cur_row_ids{8}} )
-        and
-      push @{$collapse_idx[4]{$cur_row_ids{0}}{$cur_row_ids{4}}[1]{tracks}}, (
-          $collapse_idx[5]{$cur_row_ids{0}}{$cur_row_ids{4}}{$cur_row_ids{8}} = [{ title => $cur_row_data->[8] }]
-      );
-      defined($cur_row_data->[8]) or bless ( $collapse_idx[4]{$cur_row_ids{0}}{$cur_row_ids{4}}[1]{tracks}, __NBC__ );
-
-      (! $collapse_idx[6]{$cur_row_ids{2}}{$cur_row_ids{3}} )
-        and
-      push @{$collapse_idx[0]{$cur_row_ids{10}}[1]{tracks}}, (
+        )
+      ),
+      ( defined($cur_row_data->[4]) or bless ( $collapse_idx[3]{$cur_row_ids{0}}[1]{cds}, __NBC__ ) ),
+
+      (
+        (! $collapse_idx[5]{$cur_row_ids{0}}{$cur_row_ids{4}}{$cur_row_ids{8}} )
+          and
+        push @{$collapse_idx[4]{$cur_row_ids{0}}{$cur_row_ids{4}}[1]{tracks}}, (
+            $collapse_idx[5]{$cur_row_ids{0}}{$cur_row_ids{4}}{$cur_row_ids{8}} = [{ title => $cur_row_data->[8] }]
+        )
+      ),
+      ( defined($cur_row_data->[8]) or bless ( $collapse_idx[4]{$cur_row_ids{0}}{$cur_row_ids{4}}[1]{tracks}, __NBC__ ) ),
+
+      (
+        (! $collapse_idx[6]{$cur_row_ids{2}}{$cur_row_ids{3}} )
+          and
+        push @{$collapse_idx[0]{$cur_row_ids{10}}[1]{tracks}}, (
           $collapse_idx[6]{$cur_row_ids{2}}{$cur_row_ids{3}} = [{ cd => $$cur_row_data[2], title => $cur_row_data->[3] }]
-      );
-      defined($cur_row_data->[2]) or bless ( $collapse_idx[0]{$cur_row_ids{10}}[1]{tracks}, __NBC__ );
+        )
+      ),
+      ( defined($cur_row_data->[2]) or bless ( $collapse_idx[0]{$cur_row_ids{10}}[1]{tracks}, __NBC__ ) ),
     }
 
     $#{$_[0]} = $result_pos - 1;
@@ -616,68 +749,84 @@ is_same_src (
 );
 
 is_same_src (
-  $schema->source ('CD')->_mk_row_parser({
+  ($schema->source ('CD')->_mk_row_parser({
     inflate_map => $infmap,
     collapse => 1,
     hri_style => 1,
-  }),
+    prune_null_branches => 1,
+  }))[0],
   ' my $rows_pos = 0;
-    my ($result_pos, @collapse_idx, $cur_row_data);
+    my ($result_pos, @collapse_idx, $cur_row_data, %cur_row_ids);
 
     while ($cur_row_data = (
-      ( $rows_pos >= 0 and $_[0][$rows_pos++] ) or do { $rows_pos = -1; undef } )
-        ||
+      (
+        $rows_pos >= 0
+          and
+        (
+          $_[0][$rows_pos++]
+            or
+          ( ($rows_pos = -1), undef )
+        )
+      )
+        or
       ( $_[1] and $_[1]->() )
-    ) {
+    ) ) {
+
+      # do not care about nullability here
+      ( @cur_row_ids{( 0, 2, 3, 4, 8 )} = @{$cur_row_data}[( 0, 2, 3, 4, 8 )] ),
 
       # cache expensive set of ops in a non-existent rowid slot
-      $cur_row_data->[10] = (
-        ( ( defined $cur_row_data->[0] ) && (join "\xFF", q{}, $cur_row_data->[0], q{} ))
+      ( $cur_row_ids{10} = (
+        ( ( defined $cur_row_data->[0] ) && (join "\xFF", q{}, $cur_row_ids{0}, q{} ))
           or
-        ( ( defined $cur_row_data->[2] ) && (join "\xFF", q{}, $cur_row_data->[2], q{} ))
+        ( ( defined $cur_row_data->[2] ) && (join "\xFF", q{}, $cur_row_ids{2}, q{} ))
           or
         "\0$rows_pos\0"
-      );
+      )),
 
       # a present cref in $_[1] implies lazy prefetch, implies a supplied stash in $_[2]
-      $_[1] and $result_pos and ! $collapse_idx[0]{$cur_row_data->[10]} and (unshift @{$_[2]}, $cur_row_data) and last;
+      ( $_[1] and $result_pos and ! $collapse_idx[0]{$cur_row_ids{10}} and (unshift @{$_[2]}, $cur_row_data) and last ),
 
-      $collapse_idx[0]{$cur_row_data->[10]} ||= $_[0][$result_pos++] = { year => $$cur_row_data[1] };
+      ( $collapse_idx[0]{$cur_row_ids{10}} //= $_[0][$result_pos++] = { year => $$cur_row_data[1] } ),
 
-      (! defined $cur_row_data->[0] ) ? $collapse_idx[0]{$cur_row_data->[10]}{single_track} = undef : do {
+      ( (! defined $cur_row_data->[0] ) ? $collapse_idx[0]{$cur_row_ids{10}}{single_track} = undef : do {
 
-        $collapse_idx[0]{$cur_row_data->[10]}{single_track} ||= ($collapse_idx[1]{$cur_row_data->[0]} = { trackid => $$cur_row_data[0] });
+        ( $collapse_idx[0]{$cur_row_ids{10}}{single_track} //= ($collapse_idx[1]{$cur_row_ids{0}} = { trackid => $$cur_row_data[0] }) ),
 
-        $collapse_idx[1]{$cur_row_data->[0]}{cd} ||= $collapse_idx[2]{$cur_row_data->[0]};
+        ( $collapse_idx[1]{$cur_row_ids{0}}{cd} //= $collapse_idx[2]{$cur_row_ids{0}} ),
 
-        $collapse_idx[2]{$cur_row_data->[0]}{artist} ||= ($collapse_idx[3]{$cur_row_data->[0]} = { artistid => $$cur_row_data[6] });
+        ( $collapse_idx[2]{$cur_row_ids{0}}{artist} //= ($collapse_idx[3]{$cur_row_ids{0}} = { artistid => $$cur_row_data[6] }) ),
 
-        (! defined $cur_row_data->[4] ) ? $collapse_idx[3]{$cur_row_data->[0]}{cds} = [] : do {
+        ( (! defined $cur_row_data->[4] ) ? $collapse_idx[3]{$cur_row_ids{0}}{cds} = [] : do {
 
-          (! $collapse_idx[4]{$cur_row_data->[0]}{$cur_row_data->[4]} )
-            and
-          push @{$collapse_idx[3]{$cur_row_data->[0]}{cds}}, (
-              $collapse_idx[4]{$cur_row_data->[0]}{$cur_row_data->[4]} = { cdid => $$cur_row_data[4], genreid => $$cur_row_data[7], year => $$cur_row_data[5] }
-          );
+          (
+            (! $collapse_idx[4]{$cur_row_ids{0}}{$cur_row_ids{4}} )
+              and
+            push @{$collapse_idx[3]{$cur_row_ids{0}}{cds}}, (
+                $collapse_idx[4]{$cur_row_ids{0}}{$cur_row_ids{4}} = { cdid => $$cur_row_data[4], genreid => $$cur_row_data[7], year => $$cur_row_data[5] }
+            )
+          ),
 
-          (! defined $cur_row_data->[8] ) ? $collapse_idx[4]{$cur_row_data->[0]}{$cur_row_data->[4]}{tracks} = [] : do {
+          ( (! defined $cur_row_data->[8] ) ? $collapse_idx[4]{$cur_row_ids{0}}{$cur_row_ids{4}}{tracks} = [] : do {
 
-            (! $collapse_idx[5]{$cur_row_data->[0]}{$cur_row_data->[4]}{$cur_row_data->[8]} )
+            (! $collapse_idx[5]{$cur_row_ids{0}}{$cur_row_ids{4}}{$cur_row_ids{8}} )
               and
-            push @{$collapse_idx[4]{$cur_row_data->[0]}{$cur_row_data->[4]}{tracks}}, (
-                $collapse_idx[5]{$cur_row_data->[0]}{$cur_row_data->[4]}{$cur_row_data->[8]} = { title => $$cur_row_data[8] }
-            );
-          };
-        };
-      };
-
-      (! defined $cur_row_data->[2] ) ? $collapse_idx[0]{$cur_row_data->[10]}{tracks} = [] : do {
-        (! $collapse_idx[6]{$cur_row_data->[2]}{$cur_row_data->[3]} )
-          and
-        push @{$collapse_idx[0]{$cur_row_data->[10]}{tracks}}, (
-            $collapse_idx[6]{$cur_row_data->[2]}{$cur_row_data->[3]} = { cd => $$cur_row_data[2], title => $$cur_row_data[3] }
-        );
-      };
+            push @{$collapse_idx[4]{$cur_row_ids{0}}{$cur_row_ids{4}}{tracks}}, (
+                $collapse_idx[5]{$cur_row_ids{0}}{$cur_row_ids{4}}{$cur_row_ids{8}} = { title => $$cur_row_data[8] }
+            ),
+          } ),
+        } ),
+      } ),
+
+      ( (! defined $cur_row_data->[2] ) ? $collapse_idx[0]{$cur_row_ids{10}}{tracks} = [] : do {
+        (
+          (! $collapse_idx[6]{$cur_row_ids{2}}{$cur_row_ids{3}} )
+            and
+          push @{$collapse_idx[0]{$cur_row_ids{10}}{tracks}}, (
+            $collapse_idx[6]{$cur_row_ids{2}}{$cur_row_ids{3}} = { cd => $$cur_row_data[2], title => $$cur_row_data[3] }
+          )
+        ),
+      } ),
     }
 
     $#{$_[0]} = $result_pos - 1;
@@ -685,18 +834,73 @@ is_same_src (
   'Multiple has_many on multiple branches with underdefined root, HRI-direct torture test',
 );
 
+is_same_src (
+  ($schema->source ('Owners')->_mk_row_parser({
+    inflate_map => [qw( books.title books.owner )],
+    collapse => 1,
+    prune_null_branches => 1,
+  }))[0],
+  ' my $rows_pos = 0;
+    my ($result_pos, @collapse_idx, $cur_row_data, %cur_row_ids );
+
+    while ($cur_row_data = (
+      (
+        $rows_pos >= 0
+          and
+        (
+          $_[0][$rows_pos++]
+            or
+          ( ($rows_pos = -1), undef )
+        )
+      )
+        or
+      ( $_[1] and $_[1]->() )
+    ) ) {
+
+      ( @cur_row_ids{0,1} = @{$cur_row_data}[0,1] ),
+
+      ( $cur_row_ids{3} = (
+        ( ( defined $cur_row_data->[1] ) && (join "\xFF", q{}, $cur_row_ids{1}, q{} ))
+          or
+        "\0${rows_pos}\0"
+      )),
+
+      ( $_[1] and $result_pos and ! $collapse_idx[0]{$cur_row_ids{3}} and (unshift @{$_[2]}, $cur_row_data) and last ),
+
+      # empty data for the root node
+      ( $collapse_idx[0]{$cur_row_ids{3}} //= $_[0][$result_pos++] = [] ),
+
+      ( ( ! defined $cur_row_data->[0] ) ? $collapse_idx[0]{$cur_row_ids{3}}[1]{"books"} = [] : do {
+        push @{$collapse_idx[0]{$cur_row_ids{3}}[1]{books}},
+          $collapse_idx[1]{$cur_row_ids{0}} = [ { owner => $cur_row_data->[1], title => $cur_row_data->[0] } ]
+        unless $collapse_idx[1]{$cur_row_ids{0}}
+      } ),
+    }
+
+    $#{$_[0]} = $result_pos - 1; # truncate the passed in array to where we filled it with results
+  ',
+  'Non-premultiplied implicit collapse with missing join columns',
+);
+
 done_testing;
 
 my $deparser;
-sub is_same_src {
+sub is_same_src { SKIP: {
+
+  skip "Skipping comparison of unicode-posioned source", 1
+    if DBIx::Class::_ENV_::STRESSTEST_UTF8_UPGRADE_GENERATED_COLLAPSER_SOURCE;
+
   $deparser ||= B::Deparse->new;
   local $Test::Builder::Level = $Test::Builder::Level + 1;
 
   my ($got, $expect) = @_;
 
-  $expect =~ s/__NBC__/B::perlstring($DBIx::Class::ResultSource::RowParser::Util::null_branch_class)/ge;
+  skip "Not testing equality of source containing defined-or operator on this perl $]", 1
+    if ($] < 5.010 and$expect =~ m!\Q//=!);
+
+  $expect =~ s/__NBC__/perlstring($DBIx::Class::ResultSource::RowParser::Util::null_branch_class)/ge;
 
-  $expect = "  { use strict; use warnings FATAL => 'all';\n$expect\n  }";
+  $expect = "  { use strict; use warnings FATAL => 'uninitialized';\n$expect\n  }";
 
   my @normalized = map {
     my $cref = eval "sub { $_ }" or do {
@@ -713,4 +917,4 @@ sub is_same_src {
     ;
     exit 1;
   };
-}
+} }