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Diffstat (limited to 'src/perl_checker.html.pl')
| -rw-r--r-- | src/perl_checker.html.pl | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/src/perl_checker.html.pl b/src/perl_checker.html.pl new file mode 100644 index 0000000..e90d2eb --- /dev/null +++ b/src/perl_checker.html.pl @@ -0,0 +1,168 @@ +$s = <<'EOF'; +<head><title>perl_checker</title></head> +<h1>Goals of perl_checker</h1> + +<ul> +<li> for beginners in perl: + based on what the programmer is writing, + <ul> + <li> suggest better or more standard ways to do the same + <li> detect wrong code + <br> + => a kind of automatic teacher + </ul> + +<li> for senior programmers: + detect typos, unused variables, check number + of parameters, global analysis to check method calls... + +<li> enforce the same perl style by enforcing a subset of perl of features. + In perl <a href="http://c2.com/cgi/wiki?ThereIsMoreThanOneWayToDoIt">There is more than one way to do it</a>. + In perl_checker's subset of Perl, there is not too many ways to do it. + This is especially useful for big projects. + (NB: the subset is chosen to keep a good expressivity) +</ul> + +<h1>Compared to <a href="http://perlcritic.tigris.org/">Perl-Critic</a> + +<ul> +<li>perl_checker use its own OCaml-written perl parser, which is in no way as robust as <a href="http://www.perl.com/pub/a/2005/06/09/ppi.html">PPI</a>. + A PPI require is to be able to parse non finished perl documents. + perl_checker is a checker, and it is not a big deal to die horribly on a weird perl expression, telling the programmer what to write instead. + +<li>perl_checker is <b>much</b> faster (more than 100 times) (ML pattern matching rulez) + +<li>perl_checker checks a lot more things than perlcritic: undeclared variables, unknown functions, unknown methods... + +<li>and of course perl_checker checks are different from the Conways's <a href="http://www.oreilly.com/catalog/perlbp/">Perl Best Practices</a> +</ul> + +<h1>Get it</h1> + +<a href="http://cvs.mandriva.com/cgi-bin/cvsweb.cgi/soft/perl-MDK-Common/perl_checker.src/">CVS source</a> + +<h1>Implemented features</h1> + +<dl> + <dt>white space normalization + <dd>enforce a similar coding style. In many languages you can find a coding + style document (eg: <a href="http://www.gnu.org/prep/standards_23.html">the GNU one</a>). + + TESTS=force_layout.t + + </dd> + <dt>disallow <i>complex</i> expressions + <dd>perl_checker try to ban some weird-not-used-a-lot features. + + TESTS=syntax_restrictions.t + + </dd> + <dt>suggest simpler expressions + <dd>when there is a simpler way to write an expression, suggest it. It can + also help detecting errors. + + TESTS=suggest_better.t + + </dd> + <dt>context checks + <dd>Perl has types associated with variables names, the so-called "context". + Some expressions mixing contexts are stupid, perl_checker detects them. + + TESTS=context.t + + </dd> + <dt>function call check + <dd>detection of unknown functions or mismatching prototypes (warning: since + perl is a dynamic language, some spurious warnings may occur when a function + is defined using stashes). + + TESTS=prototype.t + + </dd> + <dt>method call check + <dd>detection of unknown methods or mismatching prototypes. perl_checker + doesn't have any idea what the object type is, it simply checks if a method + with that name and that number of parameters exists. + + TESTS=method.t + + </dd> + <dt>return value check + <dd>dropping the result of a functionnally <i>pure</i> function is stupid. + using the result of a function returning void is stupid too. + + TESTS=return_value.t + + </dd> + <dt>detect some Perl traps + <dd>some Perl expressions are stupid, and one gets a warning when running + them with <tt>perl -w</tt>. The drawback are <tt>perl -w</tt> is the lack of + code coverage, it only detects expressions which are evaluated. + + TESTS=various_errors.t + +</dl> + +<h1>Todo</h1> + +Functionalities that would be nice: +<ul> + <li> add flow analysis + <li> maybe a "soft typing" type analysis + <li> detect places where imperative code can be replaced with + functional code (already done for some <b>simple</b> loops) + <li> check the number of returned values when checking prototype compliance +</ul> +EOF + +my $_rationale = <<'EOF'; +<h1>Rationale</h1> + +Perl is a big language, there is <a +href="http://c2.com/cgi/wiki?ThereIsMoreThanOneWayToDoIt">ThereIsMoreThanOneWayToDoIt</a>. +It has advantages but also some drawbacks for team project: +<ul> + <li> it is hard to learn every special rules. Automatically enforced syntax + coding rules help learning incrementally +EOF + +use lib ('test', '..'); +use read_t; +sub get_example { + my ($file) = @_; + my @tests = read_t::read_t("test/$file"); + $file =~ s|test/||; + qq(<p><a name="$file"><table border=1 cellpadding=3>\n) . + join('', map { + my $lines = join("<br>", map { "<tt>" . html_quote($_) . "</tt>" } @{$_->{lines}}); + my $logs = join("<br>", map { html_quote($_) } @{$_->{logs}}); + " <tr><td>\n", $lines, "</td><td>", $logs, "</td></tr>\n"; + } @tests) . + "</table></a>\n"; +} + +sub anchor_to_examples { + my ($s) = @_; + $s =~ s!TESTS=(\S+)!(<a href="#$1">examples</a>)!g; + $s; +} +sub fill_in_examples { + my ($s) = @_; + $s =~ s!TESTS=(\S+)!get_example($1)!ge; + $s; +} + +$s =~ s!<h1>Implemented features</h1>(.*)<h1>! + "<h1>Implemented features</h1>" . anchor_to_examples($1) . + "<h1>Examples</h1>" . fill_in_examples($1) . + "<h1>"!se; + +print $s; + +sub html_quote { + local $_ = $_[0]; + s/</</g; + s/>/>/g; + s/^(\s*)/" " x length($1)/e; + $_; +} |