+[[!tag patch patch/core]]
+
I like the idea of [[tips/integrated_issue_tracking_with_ikiwiki]], and I do so on several wikis. However, as far as I can tell, ikiwiki has no functionality which can represent dependencies between bugs and allow pagespecs to select based on dependencies. For instance, I can't write a pagespec which selects all bugs with no dependencies on bugs not marked as done. --[[JoshTriplett]]
> I started having a think about this. I'm going to start with the idea that expanding
>> I saw that this issue is targeted at by the work on [[structured page data#another_kind_of_links]]. --Ivan Z.
+>>> It's fixed now; links can have a type, such as "tag", or "dependency",
+>>> and pagespecs can match links of a given typo. --[[Joey]]
+
Okie - I've had a quick attempt at this. Initial patch attached. This one doesn't quite work.
And there is still a lot of debugging stuff in there.
>> Because you have to define all the named pagespecs in the pagespec, you sometimes end up with very long pagespecs. I found it useful to split them over multiple lines. That didn't work at one point and I added the 's' to make it work. I may have further altered the regex since then to make the 's' redundant. Remove it and see if multi-line pagespecs still work. :)
+>>> Well, I can tell you that multi-line pagespecs are supported w/o
+>>> your patch .. I use them all the time. The reason I find your
+>>> use of `/s` unlikely is because without it `\s` already matches
+>>> a newline. Only if you want to treat a newline as non-whitespace
+>>> is `/s` typically necessary. --[[Joey]]
+
> * Some changes of `@_` to `%params` in `pagespec_makeperl` do not
> make sense to me. I don't see where \%params is defined and populated,
> except with `\$params{specFunc}`.
->> I'm not a perl hacker. This was a mighty battle for me to get going. There is probably some battlefield carnage from my early struggles learning perl left here.
->> Part of this is that @_ / @params already existed as a way of passing in extra parameters. I didn't want to pollute that top level namespace - just at my own parameter (a hash) which contained the data I needed.
+>> I'm not a perl hacker. This was a mighty battle for me to get going.
+>> There is probably some battlefield carnage from my early struggles
+>> learning perl left here. Part of this is that @_ / @params already
+>> existed as a way of passing in extra parameters. I didn't want to
+>> pollute that top level namespace - just at my own parameter (a hash)
+>> which contained the data I needed.
+
+>>> I think I understand how the various `%params`
+>>> (there's not just one) work in your code now, but it's really a mess.
+>>> Explaining it in words would take pages.. It could be fixed by,
+>>> in `pagespec_makeperl` something like:
+>>>
+>>> my %specFuncs;
+>>> push @_, specFuncs => \%specFuncs;
+>>>
+>>> With that you have the hash locally available for populating
+>>> inside `pagespec_makeperl`, and when the `match_*` functions
+>>> are called the same hash data will be available inside their
+>>> `@_` or `%params`. No need to change how the functions are called
+>>> or do any of the other hacks.
+>>>
+>>> Currently, specFuncs is populated by building up code
+>>> that recursively calls `pagespec_makeperl`, and is then
+>>> evaluated when the pagespec gets evaluated. My suggested
+>>> change to `%params` will break that, but that had to change
+>>> anyway.
+>>>
+>>> It probably has a security hole, and is certianly inviting
+>>> one, since the pagespec definition is matched by a loose regexp (`.*`)
+>>> and then subject to string interpolation before being evaluated
+>>> inside perl code. I recently changed ikiwiki to never interpolate
+>>> user-supplied strings when translating pagespecs, and that
+>>> needs to happen here too. The obvious way, it seems to me,
+>>> is to not generate perl code, but just directly run perl code that
+>>> populates specFuncs.
+
+>>>> I don't think this is as bad as you make out, but your addition of the
+>>>> data array will break with the recursion my patch adds in pagespec_makeperl.
+>>>> To fix that I'll need to pass a reference to that array into pagespec_makeperl.
+>>>> I think I can then do the same thing to $params{specFuncs}. -- [[Will]]
+
+>>>>> You're right -- I did not think the recursive case through.
+>>>>> --[[Joey]]
> * Seems that the only reason `match_glob` has to check for `~` is
> because when a named spec appears in a pagespec, it is translated
>> call match_glob(). match_glob() in turn will handle the named spec. I tested this version briefly and it seemed to work. I remember looking at this again later and wondering if I had mis-understood
>> some of the logic in match_link(), which might mean there are cases where you would need an explicit call to check_named_spec_existential() - I never checked it properly after having that thought.
+>>> In the common case, `match_link` does not call `match_glob`,
+>>> because the link target it is being asked to check for is a single
+>>> page name, not a glob.
+
+>>>> A named pagespec should fall into the glob case. These two pagespecs should be the same:
+
+ link(a*)
+
+>>>> and
+
+ define(aStar, a*) and link(~aStar)
+
+>>>> In the first case, we want the pagespec to match any page that links to a page matching the glob.
+>>>> In the second case, we want the pagespec to match any page that links to a page matching the named spec.
+>>>> match_link() was already doing existential part. The patches to this code were simply to remove the `lc()`
+>>>> call from the named pagespec name. Can that `lc` be removed entirely? -- [[Will]]
+
+>>>>> I think we could get rid of it. `bestlink` will lc it itself
+>>>>> if the uppercase version does not exist; `match_glob` matches
+>>>>> insensitively.
+>>>>> --[[Joey]]
+
> * Generally, the need to modify `match_*` functions so that they
> check for and handle named pagespecs seems suboptimal, if
> only because there might be others people may want to use named
>> Possibly. I'm not sure which I prefer between the current solution and that one. Each have advantages and disadvantages.
>> It really isn't much code for the match functions to add a call to check_named_spec_existential().
+>>> But if a plugin adds its own match function, it has
+>>> to explicitly call that code to support named pagespecs.
+
+>>>> Yes, and it can do that in just three lines of code. But if we automatically check for named pagespecs all the time we
+>>>> potentially break any matching function that doesn't accept pages, or wants to use multiple arguments.
+
+>>>>> 3 lines of code, plus the functions called become part of the API,
+>>>>> don't forget about that..
+>>>>>
+>>>>> Yes, I think that is the tradeoff, the question is whether to export
+>>>>> the additional complexity needed for that flexability.
+>>>>>
+>>>>> I'd be suprised if multiple argument pagespecs become necessary..
+>>>>> with the exception of this patch there has been no need for them yet.
+>>>>>
+>>>>> There are lots of pagespecs that take data other than pages,
+>>>>> indeed, that's really the common case. So far, none of them
+>>>>> seem likely to take data that starts with a `~`. Perhaps
+>>>>> the thing to do would be to check if `~foo` is a known,
+>>>>> named pagespec, and if not, just pass it through unchanged.
+>>>>> Then there's little room for ambiguity, and this also allows
+>>>>> pagespecs like `glob(~foo*)` to match the literal page `~foo`.
+>>>>> (It will make pagespec_merge even harder tho.. see below.)
+>>>>> --[[Joey]]
+
+>>>>>> I've already used multi-argument pagespec match functions in
+>>>>>> my data plugin. It is used for having different types of links. If
+>>>>>> you want to have multiple types of links, then the match function
+>>>>>> for them needs to take both the link name and the link type.
+>>>>>> I'm trying to think of a way we could have both - automatically
+>>>>>> handle the existential case unless the function indicates somehow
+>>>>>> that it'll do it itself. Any ideas? -- [[Will]]
+
> * I need to check if your trick to avoid infinite recursion
> works if there are two named specs that recursively
> call one-another. I suspect it does, but will test this
>> It worked for me. :)
+> * I also need to verify if memoizing the named pagespecs has
+> really guarded against very expensive pagespecs DOSing the wiki..
+
> --[[Joey]]
>> There is one issue that I've been thinking about that I haven't raised anywhere (or checked myself), and that is how this all interacts with page dependencies.
->> Firstly, I'm not sure anymore that the `pagespec_merge` function will continue to work in all cases. Secondly, it seems that there are two types of dependency, and ikiwiki
->> currently only handles one of them. The first type is "Rebuild this page when any of these other pages changes" - ikiwiki handles this. The second type is "rebuild this page when
->> set of pages referred to by this pagespec changes" - ikiwiki doesn't seem to handle this. I suspect that named pagespecs would make that second type of dependency more
->> important. I'll try to come up with a good example. -- [[Will]]
+>>
+>>> I've moved the discussion of that to [[dependency_types]]. --[[Joey]]
+>>
+>> I'm not sure anymore that the `pagespec_merge` function will continue to work in all cases.
+
+>>> The problem I can see there is that if two pagespecs
+>>> get merged and both use `~foo` but define it differently,
+>>> then the second definition might be used at a point when
+>>> it shouldn't (but I haven't verified that really happens).
+>>> That could certianly be a show-stopper. --[[Joey]]
+
+>>>> I think this can happen in the new closure based code. I don't think this could happen in the old code. -- [[Will]]
+
+>>>> Even if that works, this is a good argument for having a syntactic difference between named pagespecs and normal pages.
+>>>> If you're joining two pagespecs with 'or', you don't want a named pagespec in the first part overriding a page name in the
+>>>> second part. Oh, and I assume 'or' has the right operator precedence that "a and b or c" is "(a and b) or c", and not "a and (b or c)" -- [[Will]]
+
+>>>>> Looks like its bracketed in the code anyway... -- [[Will]]
+
+>>>> Perhaps the thing to do is to have a `clear_defines()`
+>>>> function, then merging `A` and `B` yields `(A) or (clear_defines() and (B))`
+>>>> That would deal with both the cases where `A` and `B` differently
+>>>> define `~foo` as well as with the case where `A` defines `~foo` while
+>>>> `B` uses it to refer to a literal page.
+>>>> --[[Joey]]
+
+>>>>> I don't think this will work with the new patch, and I don't think it was needed with the old one.
+>>>>> Under the old patch, pagespec_makeperl() generated a string of unevaluated, self-contained, perl
+>>>>> code. When a new named pagespec was defined, a recursive call was made to get the perl code
+>>>>> for the pagespec, and then that code was used to add something like `$params{specFuncs}->{name} = sub {recursive code} and `
+>>>>> to the result of the calling function. This means that at pagespec testing time, when this code is executed, the
+>>>>> specFuncs hash is built up as the pagespec is checked. In the case of the 'or' used above, later redefinitions of
+>>>>> a named pagespec would have redefined the specFunc at the right time. It should have just worked. However...
+
+>>>>> Since my original patch, you started using closures for security reasons (and I can see the case for that). Unfortunately this
+>>>>> means that the generated perl code is no longer self-contained - it needs to be evaluated in the same closure it was generated
+>>>>> so that it has access to the data array. To make this work with the recursive call I had two options: a) make the data array a
+>>>>> reference that I pass around through the pagespec_makeperl() functions and have available when the code is finally evaluated
+>>>>> in pagespec_translate(), or b) make sure that each pagespec is evaluated in its correct closure and a perl function is returned, not a
+>>>>> string containing unevaluated perl code.
+
+>>>>> I went with option b). I did it in such a way that the hash of specfuncs is built up at translation time, not at execution time. This
+>>>>> means that with the new code you can call specfuncs that get defined out of order:
+
+ ~test and define(~test, blah)
+
+>>>>> but it also means that using a simple 'or' to join two pagespecs wont work. If you do something like this:
+
+ ~test and define(~test, foo) and define(~test, baz)
+
+>>>>> then the last definition (baz) takes precedence.
+>>>>> In the process of writing this I think I've come up with a way to change this back the way it was, still using closures. -- [[Will]]
+
+>>> My [[remove-pagespec-merge|should_optimise_pagespecs]] branch has now
+>>> solved all this by deleting the offending function :-) --[[smcv]]
+
+
+
+Patch updated to use closures rather than inline generated code for named pagespecs. Also includes some new use of ErrorReason where appropriate. -- [[Will]]
+
+> * Perl really doesn't need forward declarations, honest!
+
+>> It complained (warning, not error) when I didn't use the forward declaration. :(
+
+> * I have doubts about memoizing the anonymous sub created by
+> `pagespec_translate`.
+
+>> This is there explicitly to make sure that runtime is polynomial and not exponential.
+
+> * Think where you wrote `+{}` you can just write `{}`
+
+>> Possibly :) -- [[Will]]
----
diff --git a/IkiWiki.pm b/IkiWiki.pm
- index 4e4da11..8b3cdfe 100644
+ index 061a1c6..1e78a63 100644
--- a/IkiWiki.pm
+++ b/IkiWiki.pm
- @@ -1550,7 +1550,16 @@ sub globlist_to_pagespec ($) {
-
- sub is_globlist ($) {
- my $s=shift;
- - return ( $s =~ /[^\s]+\s+([^\s]+)/ && $1 ne "and" && $1 ne "or" );
- + return ! ($s =~ /
- + (^\s*
- + [^\s(]+ # single item
- + (\( # possibly with parens after it
- + ([^)]* # with stuff inside those parens
- + (\([^)]*\))*)* # maybe even nested parens
- + \))?\s*$
- + ) |
- + (\s and \s) | (\s or \s) # or we find 'and' or 'or' somewhere
- + /xs);
- }
-
- sub safequote ($) {
- @@ -1631,7 +1640,7 @@ sub pagespec_merge ($$) {
+ @@ -1774,8 +1774,12 @@ sub pagespec_merge ($$) {
return "($a) or ($b)";
}
-sub pagespec_translate ($) {
- +sub pagespec_makeperl ($) {
+ +# is perl really so dumb it requires a forward declaration for recursive calls?
+ +sub pagespec_translate ($$);
+ +
+ +sub pagespec_translate ($$) {
my $spec=shift;
+ + my $specFuncsRef=shift;
- # Support for old-style GlobLists.
- @@ -1650,12 +1659,14 @@ sub pagespec_translate ($) {
+ # Convert spec to perl code.
+ my $code="";
+ @@ -1789,7 +1793,9 @@ sub pagespec_translate ($) {
|
\) # )
|
- \w+\([^\)]*\) # command(params)
- + define\(\s*~\w+\s*,((\([^()]*\)) | ([^()]+))+\) # define(~specName, spec) - spec can contain parens 1 deep
+ + define\(\s*~\w+\s*,((\([^()]*\)) | ([^()]+))+\) # define(~specName, spec) - spec can contain parens 1 deep
+ |
+ \w+\([^()]*\) # command(params) - params cannot contain parens
|
[^\s()]+ # any other text
)
- \s* # ignore whitespace
- - }igx) {
- + }igxs) {
- my $word=$1;
- if (lc $word eq 'and') {
- $code.=' &&';
- @@ -1666,16 +1677,23 @@ sub pagespec_translate ($) {
+ @@ -1805,10 +1811,19 @@ sub pagespec_translate ($) {
elsif ($word eq "(" || $word eq ")" || $word eq "!") {
$code.=' '.$word;
}
- elsif ($word =~ /^(\w+)\((.*)\)$/) {
- + elsif ($word =~ /^define\(\s*~(\w+)\s*,(.*)\)$/s) {
- + $code .= " (\$params{specFuncs}->{$1}="; # (exists \$params{specFuncs}) &&
- + $code .= "memoize(";
- + $code .= &pagespec_makeperl($2);
- + $code .= ")";
- + $code .= ") ";
+ + elsif ($word =~ /^define\(\s*(~\w+)\s*,(.*)\)$/s) {
+ + my $name = $1;
+ + my $subSpec = $2;
+ + my $newSpecFunc = pagespec_translate($subSpec, $specFuncsRef);
+ + return if $@ || ! defined $newSpecFunc;
+ + $specFuncsRef->{$name} = $newSpecFunc;
+ + push @data, qq{Created named pagespec "$name"};
+ + $code.="IkiWiki::SuccessReason->new(\$data[$#data])";
+ }
+ elsif ($word =~ /^(\w+)\((.*)\)$/s) {
if (exists $IkiWiki::PageSpec::{"match_$1"}) {
- - $code.="IkiWiki::PageSpec::match_$1(\$page, ".safequote($2).", \@_)";
- + $code.="IkiWiki::PageSpec::match_$1(\$page, ".safequote($2).", \%params)";
+ push @data, $2;
+ - $code.="IkiWiki::PageSpec::match_$1(\$page, \$data[$#data], \@_)";
+ + $code.="IkiWiki::PageSpec::match_$1(\$page, \$data[$#data], \@_, specFuncs => \$specFuncsRef)";
}
else {
- $code.=' 0';
- }
+ push @data, qq{unknown function in pagespec "$word"};
+ @@ -1817,7 +1832,7 @@ sub pagespec_translate ($) {
}
else {
- - $code.=" IkiWiki::PageSpec::match_glob(\$page, ".safequote($word).", \@_)";
- + $code.=" IkiWiki::PageSpec::match_glob(\$page, ".safequote($word).", \%params)";
+ push @data, $word;
+ - $code.=" IkiWiki::PageSpec::match_glob(\$page, \$data[$#data], \@_)";
+ + $code.=" IkiWiki::PageSpec::match_glob(\$page, \$data[$#data], \@_, specFuncs => \$specFuncsRef)";
}
}
- @@ -1683,8 +1701,18 @@ sub pagespec_translate ($) {
- $code=0;
+ @@ -1826,7 +1841,7 @@ sub pagespec_translate ($) {
}
- + return 'sub { my $page=shift; my %params = @_; '.$code.' }';
- +}
- +
- +sub pagespec_translate ($) {
- + my $spec=shift;
- +
- + my $code = pagespec_makeperl($spec);
- +
- + # print STDERR "Spec '$spec' generated code '$code'\n";
- +
no warnings;
- return eval 'sub { my $page=shift; '.$code.' }';
- + return eval $code;
+ + return eval 'memoize (sub { my $page=shift; '.$code.' })';
}
sub pagespec_match ($$;@) {
- @@ -1699,7 +1727,7 @@ sub pagespec_match ($$;@) {
+ @@ -1839,7 +1854,7 @@ sub pagespec_match ($$;@) {
+ unshift @params, 'location';
+ }
- my $sub=pagespec_translate($spec);
- return IkiWiki::FailReason->new("syntax error in pagespec \"$spec\"") if $@;
- - return $sub->($page, @params);
- + return $sub->($page, @params, specFuncs => {});
- }
+ - my $sub=pagespec_translate($spec);
+ + my $sub=pagespec_translate($spec, +{});
+ return IkiWiki::ErrorReason->new("syntax error in pagespec \"$spec\"")
+ if $@ || ! defined $sub;
+ return $sub->($page, @params);
+ @@ -1850,7 +1865,7 @@ sub pagespec_match_list ($$;@) {
+ my $spec=shift;
+ my @params=@_;
+ - my $sub=pagespec_translate($spec);
+ + my $sub=pagespec_translate($spec, +{});
+ error "syntax error in pagespec \"$spec\""
+ if $@ || ! defined $sub;
+
+ @@ -1872,7 +1887,7 @@ sub pagespec_match_list ($$;@) {
sub pagespec_valid ($) {
- @@ -1748,11 +1776,78 @@ sub new {
+ my $spec=shift;
+
+ - my $sub=pagespec_translate($spec);
+ + my $sub=pagespec_translate($spec, +{});
+ return ! $@;
+ }
+
+ @@ -1919,6 +1934,68 @@ sub new {
package IkiWiki::PageSpec;
+ my $page=shift;
+ my $specName=shift;
+ my %params=@_;
- +
- + error("Unable to find specFuncs in params to check_named_spec()!") unless exists $params{specFuncs};
+ +
+ + return IkiWiki::ErrorReason->new("Unable to find specFuncs in params to check_named_spec()!")
+ + unless exists $params{specFuncs};
+
+ my $specFuncsRef=$params{specFuncs};
- +
- + return IkiWiki::FailReason->new("Named page spec '$specName' is not valid")
+ +
+ + return IkiWiki::ErrorReason->new("Named page spec '$specName' is not valid")
+ unless (substr($specName, 0, 1) eq '~');
- +
- + $specName = substr($specName, 1);
+
+ if (exists $specFuncsRef->{$specName}) {
+ # remove the named spec from the spec refs
+ $specFuncsRef->{$specName} = $sub;
+ return $result;
+ } else {
- + return IkiWiki::FailReason->new("Page spec '$specName' does not exist");
+ + return IkiWiki::ErrorReason->new("Page spec '$specName' does not exist");
+ }
+}
+
+ my $specName=shift;
+ my $funcref=shift;
+ my %params=@_;
- +
- + error("Unable to find specFuncs in params to check_named_spec_existential()!") unless exists $params{specFuncs};
+ +
+ + return IkiWiki::ErrorReason->new("Unable to find specFuncs in params to check_named_spec_existential()!")
+ + unless exists $params{specFuncs};
+ my $specFuncsRef=$params{specFuncs};
+
- + return IkiWiki::FailReason->new("Named page spec '$specName' is not valid")
+ + return IkiWiki::ErrorReason->new("Named page spec '$specName' is not valid")
+ unless (substr($specName, 0, 1) eq '~');
- + $specName = substr($specName, 1);
- +
+ +
+ if (exists $specFuncsRef->{$specName}) {
+ # remove the named spec from the spec refs
+ # when we recurse to avoid infinite recursion
+ my $tempResult = $funcref->($page, $nextpage, %params);
+ if ($tempResult) {
+ $specFuncsRef->{$specName} = $sub;
- + return $tempResult;
+ + return IkiWiki::SuccessReason->new("Existential check of '$specName' matches because $tempResult");
+ }
+ }
+ }
+ $specFuncsRef->{$specName} = $sub;
+ return IkiWiki::FailReason->new("No page in spec '$specName' was successfully matched");
+ } else {
- + return IkiWiki::FailReason->new("Named page spec '$specName' does not exist");
+ + return IkiWiki::ErrorReason->new("Named page spec '$specName' does not exist");
+ }
+}
+
- sub match_glob ($$;@) {
- my $page=shift;
+ sub derel ($$) {
+ my $path=shift;
+ my $from=shift;
+ @@ -1937,6 +2014,10 @@ sub match_glob ($$;@) {
my $glob=shift;
my %params=@_;
+ return check_named_spec($page, $glob, %params);
+ }
+
- my $from=exists $params{location} ? $params{location} : '';
-
- # relative matching
- @@ -1782,11 +1877,12 @@ sub match_internal ($$;@) {
+ $glob=derel($glob, $params{location});
+
+ my $regexp=IkiWiki::glob2re($glob);
+ @@ -1959,8 +2040,9 @@ sub match_internal ($$;@) {
sub match_link ($$;@) {
my $page=shift;
- my $link=lc(shift);
- + my $fulllink=shift;
+ + my $fullLink=shift;
my %params=@_;
- + my $link=lc($fulllink);
+ + my $link=lc($fullLink);
+ $link=derel($link, $params{location});
my $from=exists $params{location} ? $params{location} : '';
- -
- +
- # relative matching
- if ($link =~ m!^\.! && defined $from) {
- $from=~s#/?[^/]+$##;
- @@ -1804,19 +1900,32 @@ sub match_link ($$;@) {
+ @@ -1975,25 +2057,37 @@ sub match_link ($$;@) {
}
else {
return IkiWiki::SuccessReason->new("$page links to page $p matching $link")
- if match_glob($p, $link, %params);
- + if match_glob($p, $fulllink, %params);
+ + if match_glob($p, $fullLink, %params);
+ $p=~s/^\///;
+ $link=~s/^\///;
+ return IkiWiki::SuccessReason->new("$page links to page $p matching $link")
+ - if match_glob($p, $link, %params);
+ + if match_glob($p, $fullLink, %params);
}
}
return IkiWiki::FailReason->new("$page does not link to $link");
sub match_created_before ($$;@) {
my $page=shift;
my $testpage=shift;
- + my @params=@_;
+ my %params=@_;
+ -
+
+ if (substr($testpage, 0, 1) eq '~') {
- + return check_named_spec_existential($page, $testpage, \&match_created_before, @params);
+ + return check_named_spec_existential($page, $testpage, \&match_created_before, %params);
+ }
+ +
+ $testpage=derel($testpage, $params{location});
if (exists $IkiWiki::pagectime{$testpage}) {
- if ($IkiWiki::pagectime{$page} < $IkiWiki::pagectime{$testpage}) {
- @@ -1834,6 +1943,11 @@ sub match_created_before ($$;@) {
- sub match_created_after ($$;@) {
- my $page=shift;
+ @@ -2014,6 +2108,10 @@ sub match_created_after ($$;@) {
my $testpage=shift;
- + my @params=@_;
- +
+ my %params=@_;
+
+ if (substr($testpage, 0, 1) eq '~') {
- + return check_named_spec_existential($page, $testpage, \&match_created_after, @params);
+ + return check_named_spec_existential($page, $testpage, \&match_created_after, %params);
+ }
+ +
+ $testpage=derel($testpage, $params{location});
if (exists $IkiWiki::pagectime{$testpage}) {
- if ($IkiWiki::pagectime{$page} > $IkiWiki::pagectime{$testpage}) {