search: add comments wrt codesearch, reduce ops

Add some comments about various usages of xdb_shards_flat and
mset since the addition of CodeSearch (and other search things)
subclassing it may become confusing.

Since we're in the area, we can also avoid an extra hash
lookups/initializations and reduce Perl ops in various places.

diff --git a/lib/PublicInbox/Search.pm b/lib/PublicInbox/Search.pm
index 6c3d9f93e1c8a1bd49b5ff3b11695eb3cc38fb7b..6986cb88e5a7fbc97078f2218be3e795fbf09ac9 100644 (file)
--- a/lib/PublicInbox/Search.pm
+++ b/lib/PublicInbox/Search.pm
@@ -209,19 +209,19 @@ sub xdb_shards_flat ($) {
        my (@xdb, $slow_phrase);
        load_xapian();
        $self->{qp_flags} //= $QP_FLAGS;
-       if ($xpfx =~ m!/xapian[0-9]+\z!) {
+       if ($xpfx =~ m!/xapian[0-9]+\z!) { # v1
                @xdb = ($X{Database}->new($xpfx));
                $self->{qp_flags} |= FLAG_PHRASE() if !-f "$xpfx/iamchert";
-       } else {
+       } else { # v2, eidx, cidx
                opendir(my $dh, $xpfx) or return (); # not initialized yet
                # We need numeric sorting so shard[0] is first for reading
                # Xapian metadata, if needed
                my $last = max(grep(/\A[0-9]+\z/, readdir($dh))) // return ();
-               for (0..$last) {
-                       my $shard_dir = "$self->{xpfx}/$_";
-                       push @xdb, $X{Database}->new($shard_dir);
+               @xdb = map {
+                       my $shard_dir = "$xpfx/$_";
                        $slow_phrase ||= -f "$shard_dir/iamchert";
-               }
+                       $X{Database}->new($shard_dir);
+               } (0..$last);
                $self->{qp_flags} |= FLAG_PHRASE() if !$slow_phrase;
        }
        @xdb;
@@ -371,31 +371,28 @@ sub query_approxidate {
        date_parse_finalize($git, $to_parse, $_[2]) if $to_parse;
 }
 
-# read-only
+# read-only, for mail only (codesearch has different rules)
 sub mset {
-       my ($self, $query_string, $opt) = @_;
-       $opt ||= {};
+       my ($self, $qry_str, $opt) = @_;
        my $qp = $self->{qp} //= $self->qparse_new;
-       my $query = $qp->parse_query($query_string, $self->{qp_flags});
+       my $qry = $qp->parse_query($qry_str, $self->{qp_flags});
        if (defined(my $eidx_key = $opt->{eidx_key})) {
-               $query = $X{Query}->new(OP_FILTER(), $query, 'O'.$eidx_key);
+               $qry = $X{Query}->new(OP_FILTER(), $qry, 'O'.$eidx_key);
        }
        if (defined(my $uid_range = $opt->{uid_range})) {
                my $range = $X{Query}->new(OP_VALUE_RANGE(), UID,
                                        sortable_serialise($uid_range->[0]),
                                        sortable_serialise($uid_range->[1]));
-               $query = $X{Query}->new(OP_FILTER(), $query, $range);
+               $qry = $X{Query}->new(OP_FILTER(), $qry, $range);
        }
        if (defined(my $tid = $opt->{threadid})) {
                $tid = sortable_serialise($tid);
-               $query = $X{Query}->new(OP_FILTER(), $query,
-                               $X{Query}->new(OP_VALUE_RANGE(), THREADID, $tid, $tid));
+               $qry = $X{Query}->new(OP_FILTER(), $qry,
+                       $X{Query}->new(OP_VALUE_RANGE(), THREADID, $tid, $tid));
        }
 
-       my $xdb = xdb($self);
-       my $enq = $X{Enquire}->new($xdb);
-       $enq->set_query($query);
-       $opt ||= {};
+       my $enq = $X{Enquire}->new(xdb($self));
+       $enq->set_query($qry);
        my $rel = $opt->{relevance} // 0;
        if ($rel == -2) { # ORDER BY docid/UID (highest first)
                $enq->set_weighting_scheme($X{BoolWeight}->new);
@@ -411,9 +408,8 @@ sub mset {
 
        # `lei q -t / --threads' or JMAP collapseThreads; but don't collapse
        # on `-tt' ({threads} > 1) which sets the Flagged|Important keyword
-       if (($opt->{threads} // 0) == 1 && has_threadid($self)) {
+       (($opt->{threads} // 0) == 1 && has_threadid($self)) and
                $enq->set_collapse_key(THREADID);
-       }
        retry_reopen($self, \&enquire_once, $enq,
                        $opt->{offset} || 0, $opt->{limit} || 50);
 }