macros.rs

  1// Copyright (c) 2017-2018 Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
  2//
  3// This Source Code Form is subject to the terms of the Mozilla Public
  4// License, v. 2.0. If a copy of the MPL was not distributed with this
  5// file, You can obtain one at http://mozilla.org/MPL/2.0/.
  6
  7macro_rules! get_attr {
  8    ($elem:ident, $attr:tt, $type:tt) => (
  9        get_attr!($elem, $attr, $type, value, value.parse()?)
 10    );
 11    ($elem:ident, $attr:tt, optional_empty, $value:ident, $func:expr) => (
 12        match $elem.attr($attr) {
 13            Some("") => None,
 14            Some($value) => Some($func),
 15            None => None,
 16        }
 17    );
 18    ($elem:ident, $attr:tt, optional, $value:ident, $func:expr) => (
 19        match $elem.attr($attr) {
 20            Some($value) => Some($func),
 21            None => None,
 22        }
 23    );
 24    ($elem:ident, $attr:tt, required, $value:ident, $func:expr) => (
 25        match $elem.attr($attr) {
 26            Some($value) => $func,
 27            None => return Err(::error::Error::ParseError(concat!("Required attribute '", $attr, "' missing."))),
 28        }
 29    );
 30    ($elem:ident, $attr:tt, default, $value:ident, $func:expr) => (
 31        match $elem.attr($attr) {
 32            Some($value) => $func,
 33            None => ::std::default::Default::default(),
 34        }
 35    );
 36}
 37
 38macro_rules! generate_attribute {
 39    ($(#[$meta:meta])* $elem:ident, $name:tt, {$($(#[$a_meta:meta])* $a:ident => $b:tt),+,}) => (
 40        generate_attribute!($(#[$meta])* $elem, $name, {$($(#[$a_meta])* $a => $b),+});
 41    );
 42    ($(#[$meta:meta])* $elem:ident, $name:tt, {$($(#[$a_meta:meta])* $a:ident => $b:tt),+,}, Default = $default:ident) => (
 43        generate_attribute!($(#[$meta])* $elem, $name, {$($(#[$a_meta])* $a => $b),+}, Default = $default);
 44    );
 45    ($(#[$meta:meta])* $elem:ident, $name:tt, {$($(#[$a_meta:meta])* $a:ident => $b:tt),+}) => (
 46        $(#[$meta])*
 47        #[derive(Debug, Clone, PartialEq)]
 48        pub enum $elem {
 49            $(
 50                $(#[$a_meta])*
 51                $a
 52            ),+
 53        }
 54        impl ::std::str::FromStr for $elem {
 55            type Err = ::error::Error;
 56            fn from_str(s: &str) -> Result<$elem, ::error::Error> {
 57                Ok(match s {
 58                    $($b => $elem::$a),+,
 59                    _ => return Err(::error::Error::ParseError(concat!("Unknown value for '", $name, "' attribute."))),
 60                })
 61            }
 62        }
 63        impl ::minidom::IntoAttributeValue for $elem {
 64            fn into_attribute_value(self) -> Option<String> {
 65                Some(String::from(match self {
 66                    $($elem::$a => $b),+
 67                }))
 68            }
 69        }
 70    );
 71    ($(#[$meta:meta])* $elem:ident, $name:tt, {$($(#[$a_meta:meta])* $a:ident => $b:tt),+}, Default = $default:ident) => (
 72        $(#[$meta])*
 73        #[derive(Debug, Clone, PartialEq)]
 74        pub enum $elem {
 75            $(
 76                $(#[$a_meta])*
 77                $a
 78            ),+
 79        }
 80        impl ::std::str::FromStr for $elem {
 81            type Err = ::error::Error;
 82            fn from_str(s: &str) -> Result<$elem, ::error::Error> {
 83                Ok(match s {
 84                    $($b => $elem::$a),+,
 85                    _ => return Err(::error::Error::ParseError(concat!("Unknown value for '", $name, "' attribute."))),
 86                })
 87            }
 88        }
 89        impl ::minidom::IntoAttributeValue for $elem {
 90            #[allow(unreachable_patterns)]
 91            fn into_attribute_value(self) -> Option<String> {
 92                Some(String::from(match self {
 93                    $elem::$default => return None,
 94                    $($elem::$a => $b),+
 95                }))
 96            }
 97        }
 98        impl ::std::default::Default for $elem {
 99            fn default() -> $elem {
100                $elem::$default
101            }
102        }
103    );
104    ($(#[$meta:meta])* $elem:ident, $name:tt, bool) => (
105        $(#[$meta])*
106        #[derive(Debug, Clone, PartialEq)]
107        pub enum $elem {
108            /// True value, represented by either 'true' or '1'.
109            True,
110            /// False value, represented by either 'false' or '0'.
111            False,
112        }
113        impl ::std::str::FromStr for $elem {
114            type Err = ::error::Error;
115            fn from_str(s: &str) -> Result<Self, ::error::Error> {
116                Ok(match s {
117                    "true" | "1" => $elem::True,
118                    "false" | "0" => $elem::False,
119                    _ => return Err(::error::Error::ParseError(concat!("Unknown value for '", $name, "' attribute."))),
120                })
121            }
122        }
123        impl ::minidom::IntoAttributeValue for $elem {
124            fn into_attribute_value(self) -> Option<String> {
125                match self {
126                    $elem::True => Some(String::from("true")),
127                    $elem::False => None
128                }
129            }
130        }
131        impl ::std::default::Default for $elem {
132            fn default() -> $elem {
133                $elem::False
134            }
135        }
136    );
137}
138
139macro_rules! generate_element_enum {
140    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident, {$($(#[$enum_meta:meta])* $enum:ident => $enum_name:tt),+,}) => (
141        generate_element_enum!($(#[$meta])* $elem, $name, $ns, {$($(#[$enum_meta])* $enum => $enum_name),+});
142    );
143    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident, {$($(#[$enum_meta:meta])* $enum:ident => $enum_name:tt),+}) => (
144        $(#[$meta])*
145        #[derive(Debug, Clone, PartialEq)]
146        pub enum $elem {
147            $(
148            $(#[$enum_meta])*
149            $enum
150            ),+
151        }
152        impl ::try_from::TryFrom<::minidom::Element> for $elem {
153            type Err = ::error::Error;
154            fn try_from(elem: ::minidom::Element) -> Result<$elem, ::error::Error> {
155                check_ns_only!(elem, $name, $ns);
156                check_no_children!(elem, $name);
157                check_no_attributes!(elem, $name);
158                Ok(match elem.name() {
159                    $($enum_name => $elem::$enum,)+
160                    _ => return Err(::error::Error::ParseError(concat!("This is not a ", $name, " element."))),
161                })
162            }
163        }
164        impl From<$elem> for ::minidom::Element {
165            fn from(elem: $elem) -> ::minidom::Element {
166                ::minidom::Element::builder(match elem {
167                    $($elem::$enum => $enum_name,)+
168                }).ns(::ns::$ns)
169                  .build()
170            }
171        }
172    );
173}
174
175macro_rules! generate_attribute_enum {
176    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident, $attr:tt, {$($(#[$enum_meta:meta])* $enum:ident => $enum_name:tt),+,}) => (
177        generate_attribute_enum!($(#[$meta])* $elem, $name, $ns, $attr, {$($(#[$enum_meta])* $enum => $enum_name),+});
178    );
179    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident, $attr:tt, {$($(#[$enum_meta:meta])* $enum:ident => $enum_name:tt),+}) => (
180        $(#[$meta])*
181        #[derive(Debug, Clone, PartialEq)]
182        pub enum $elem {
183            $(
184            $(#[$enum_meta])*
185            $enum
186            ),+
187        }
188        impl ::try_from::TryFrom<::minidom::Element> for $elem {
189            type Err = ::error::Error;
190            fn try_from(elem: ::minidom::Element) -> Result<$elem, ::error::Error> {
191                check_ns_only!(elem, $name, $ns);
192                check_no_children!(elem, $name);
193                check_no_unknown_attributes!(elem, $name, [$attr]);
194                Ok(match get_attr!(elem, $attr, required) {
195                    $($enum_name => $elem::$enum,)+
196                    _ => return Err(::error::Error::ParseError(concat!("Invalid ", $name, " ", $attr, " value."))),
197                })
198            }
199        }
200        impl From<$elem> for ::minidom::Element {
201            fn from(elem: $elem) -> ::minidom::Element {
202                ::minidom::Element::builder($name)
203                        .ns(::ns::$ns)
204                        .attr($attr, match elem {
205                             $($elem::$enum => $enum_name,)+
206                         })
207                         .build()
208            }
209        }
210    );
211}
212
213macro_rules! check_self {
214    ($elem:ident, $name:tt, $ns:ident) => (
215        check_self!($elem, $name, $ns, $name);
216    );
217    ($elem:ident, $name:tt, $ns:ident, $pretty_name:tt) => (
218        if !$elem.is($name, ::ns::$ns) {
219            return Err(::error::Error::ParseError(concat!("This is not a ", $pretty_name, " element.")));
220        }
221    );
222}
223
224macro_rules! check_ns_only {
225    ($elem:ident, $name:tt, $ns:ident) => (
226        if !$elem.has_ns(::ns::$ns) {
227            return Err(::error::Error::ParseError(concat!("This is not a ", $name, " element.")));
228        }
229    );
230}
231
232macro_rules! check_no_children {
233    ($elem:ident, $name:tt) => (
234        for _ in $elem.children() {
235            return Err(::error::Error::ParseError(concat!("Unknown child in ", $name, " element.")));
236        }
237    );
238}
239
240macro_rules! check_no_attributes {
241    ($elem:ident, $name:tt) => (
242        for _ in $elem.attrs() {
243            return Err(::error::Error::ParseError(concat!("Unknown attribute in ", $name, " element.")));
244        }
245    );
246}
247
248macro_rules! check_no_unknown_attributes {
249    ($elem:ident, $name:tt, [$($attr:tt),*]) => (
250        for (_attr, _) in $elem.attrs() {
251            $(
252            if _attr == $attr {
253                continue;
254            }
255            )*
256            return Err(::error::Error::ParseError(concat!("Unknown attribute in ", $name, " element.")));
257        }
258    );
259}
260
261macro_rules! generate_empty_element {
262    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident) => (
263        $(#[$meta])*
264        #[derive(Debug, Clone)]
265        pub struct $elem;
266
267        impl ::try_from::TryFrom<::minidom::Element> for $elem {
268            type Err = ::error::Error;
269
270            fn try_from(elem: ::minidom::Element) -> Result<$elem, ::error::Error> {
271                check_self!(elem, $name, $ns);
272                check_no_children!(elem, $name);
273                check_no_attributes!(elem, $name);
274                Ok($elem)
275            }
276        }
277
278        impl From<$elem> for ::minidom::Element {
279            fn from(_: $elem) -> ::minidom::Element {
280                ::minidom::Element::builder($name)
281                        .ns(::ns::$ns)
282                        .build()
283            }
284        }
285    );
286}
287
288macro_rules! generate_id {
289    ($(#[$meta:meta])* $elem:ident) => (
290        $(#[$meta])*
291        #[derive(Debug, Clone, PartialEq, Eq, Hash)]
292        pub struct $elem(pub String);
293        impl ::std::str::FromStr for $elem {
294            type Err = ::error::Error;
295            fn from_str(s: &str) -> Result<$elem, ::error::Error> {
296                // TODO: add a way to parse that differently when needed.
297                Ok($elem(String::from(s)))
298            }
299        }
300        impl ::minidom::IntoAttributeValue for $elem {
301            fn into_attribute_value(self) -> Option<String> {
302                Some(self.0)
303            }
304        }
305    );
306}
307
308macro_rules! generate_elem_id {
309    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident) => (
310        $(#[$meta])*
311        #[derive(Debug, Clone, PartialEq, Eq, Hash)]
312        pub struct $elem(pub String);
313        impl ::std::str::FromStr for $elem {
314            type Err = ::error::Error;
315            fn from_str(s: &str) -> Result<$elem, ::error::Error> {
316                // TODO: add a way to parse that differently when needed.
317                Ok($elem(String::from(s)))
318            }
319        }
320        impl ::try_from::TryFrom<::minidom::Element> for $elem {
321            type Err = ::error::Error;
322            fn try_from(elem: ::minidom::Element) -> Result<$elem, ::error::Error> {
323                check_self!(elem, $name, $ns);
324                check_no_children!(elem, $name);
325                check_no_attributes!(elem, $name);
326                // TODO: add a way to parse that differently when needed.
327                Ok($elem(elem.text()))
328            }
329        }
330        impl From<$elem> for ::minidom::Element {
331            fn from(elem: $elem) -> ::minidom::Element {
332                ::minidom::Element::builder($name)
333                        .ns(::ns::$ns)
334                        .append(elem.0)
335                        .build()
336            }
337        }
338    );
339}
340
341macro_rules! generate_element_with_text {
342    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident, $(#[$text_meta:meta])* $text_ident:ident: $codec:ident < $text_type:ty >) => (
343        generate_element_with_text!($(#[$meta])* $elem, $name, $ns, [], $(#[$text_meta])* $text_ident: $codec<$text_type>);
344    );
345    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident, [$($(#[$attr_meta:meta])* $attr:ident: $attr_type:ty = $attr_name:tt => $attr_action:tt),*], $(#[$text_meta:meta])* $text_ident:ident: $codec:ident < $text_type:ty >) => (
346        $(#[$meta])*
347        #[derive(Debug, Clone)]
348        pub struct $elem {
349            $(
350            $(#[$attr_meta])*
351            pub $attr: $attr_type,
352            )*
353            $(#[$text_meta])*
354            pub $text_ident: $text_type,
355        }
356
357        impl ::try_from::TryFrom<::minidom::Element> for $elem {
358            type Err = ::error::Error;
359
360            fn try_from(elem: ::minidom::Element) -> Result<$elem, ::error::Error> {
361                check_self!(elem, $name, $ns);
362                check_no_children!(elem, $name);
363                check_no_unknown_attributes!(elem, $name, [$($attr_name),*]);
364                Ok($elem {
365                    $(
366                    $attr: get_attr!(elem, $attr_name, $attr_action),
367                    )*
368                    $text_ident: $codec::decode(&elem.text())?,
369                })
370            }
371        }
372
373        impl From<$elem> for ::minidom::Element {
374            fn from(elem: $elem) -> ::minidom::Element {
375                ::minidom::Element::builder($name)
376                        .ns(::ns::$ns)
377                        $(
378                        .attr($attr_name, elem.$attr)
379                        )*
380                        .append($codec::encode(&elem.$text_ident))
381                        .build()
382            }
383        }
384    );
385}
386
387macro_rules! start_decl {
388    (Vec, $type:ty) => (
389        Vec<$type>
390    );
391    (Option, $type:ty) => (
392        Option<$type>
393    );
394    (Required, $type:ty) => (
395        $type
396    );
397}
398
399macro_rules! start_parse_elem {
400    ($temp:ident: Vec) => (
401        let mut $temp = Vec::new();
402    );
403    ($temp:ident: Option) => (
404        let mut $temp = None;
405    );
406    ($temp:ident: Required) => (
407        let mut $temp = None;
408    );
409}
410
411macro_rules! do_parse {
412    ($elem:ident, Element) => (
413        $elem.clone()
414    );
415    ($elem:ident, String) => (
416        $elem.text()
417    );
418    ($elem:ident, $constructor:ident) => (
419        $constructor::try_from($elem.clone())?
420    );
421}
422
423macro_rules! do_parse_elem {
424    ($temp:ident: Vec = $constructor:ident => $elem:ident, $name:tt, $parent_name:tt) => (
425        $temp.push(do_parse!($elem, $constructor));
426    );
427    ($temp:ident: Option = $constructor:ident => $elem:ident, $name:tt, $parent_name:tt) => (
428        if $temp.is_some() {
429            return Err(::error::Error::ParseError(concat!("Element ", $parent_name, " must not have more than one ", $name, " child.")));
430        }
431        $temp = Some(do_parse!($elem, $constructor));
432    );
433    ($temp:ident: Required = $constructor:ident => $elem:ident, $name:tt, $parent_name:tt) => (
434        if $temp.is_some() {
435            return Err(::error::Error::ParseError(concat!("Element ", $parent_name, " must not have more than one ", $name, " child.")));
436        }
437        $temp = Some(do_parse!($elem, $constructor));
438    );
439}
440
441macro_rules! finish_parse_elem {
442    ($temp:ident: Vec = $name:tt, $parent_name:tt) => (
443        $temp
444    );
445    ($temp:ident: Option = $name:tt, $parent_name:tt) => (
446        $temp
447    );
448    ($temp:ident: Required = $name:tt, $parent_name:tt) => (
449        $temp.ok_or(::error::Error::ParseError(concat!("Missing child ", $name, " in ", $parent_name, " element.")))?
450    );
451}
452
453macro_rules! generate_serialiser {
454    ($parent:ident, $elem:ident, Required, String, ($name:tt, $ns:ident)) => (
455        ::minidom::Element::builder($name)
456            .ns(::ns::$ns)
457            .append($parent.$elem)
458            .build()
459    );
460    ($parent:ident, $elem:ident, Option, String, ($name:tt, $ns:ident)) => (
461        $parent.$elem.map(|elem|
462            ::minidom::Element::builder($name)
463                .ns(::ns::$ns)
464                .append(elem)
465                .build())
466    );
467    ($parent:ident, $elem:ident, $_:ident, $constructor:ident, ($name:tt, $ns:ident)) => (
468        $parent.$elem
469    );
470}
471
472macro_rules! generate_element {
473    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident, attributes: [$($(#[$attr_meta:meta])* $attr:ident: $attr_type:ty = $attr_name:tt => $attr_action:tt),+,]) => (
474        generate_element!($(#[$meta])* $elem, $name, $ns, attributes: [$($(#[$attr_meta])* $attr: $attr_type = $attr_name => $attr_action),*], children: []);
475    );
476    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident, attributes: [$($(#[$attr_meta:meta])* $attr:ident: $attr_type:ty = $attr_name:tt => $attr_action:tt),+]) => (
477        generate_element!($(#[$meta])* $elem, $name, $ns, attributes: [$($(#[$attr_meta])* $attr: $attr_type = $attr_name => $attr_action),*], children: []);
478    );
479    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident, children: [$($(#[$child_meta:meta])* $child_ident:ident: $coucou:tt<$child_type:ty> = ($child_name:tt, $child_ns:ident) => $child_constructor:ident),*]) => (
480        generate_element!($(#[$meta])* $elem, $name, $ns, attributes: [], children: [$($(#[$child_meta])* $child_ident: $coucou<$child_type> = ($child_name, $child_ns) => $child_constructor),*]);
481    );
482    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident, attributes: [$($(#[$attr_meta:meta])* $attr:ident: $attr_type:ty = $attr_name:tt => $attr_action:tt),*,], children: [$($(#[$child_meta:meta])* $child_ident:ident: $coucou:tt<$child_type:ty> = ($child_name:tt, $child_ns:ident) => $child_constructor:ident),*]) => (
483        generate_element!($(#[$meta])* $elem, $name, $ns, attributes: [$($(#[$attr_meta])* $attr: $attr_type = $attr_name => $attr_action),*], children: [$($(#[$child_meta])* $child_ident: $coucou<$child_type> = ($child_name, $child_ns) => $child_constructor),*]);
484    );
485    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident, attributes: [$($(#[$attr_meta:meta])* $attr:ident: $attr_type:ty = $attr_name:tt => $attr_action:tt),*], children: [$($(#[$child_meta:meta])* $child_ident:ident: $coucou:tt<$child_type:ty> = ($child_name:tt, $child_ns:ident) => $child_constructor:ident),*]) => (
486        $(#[$meta])*
487        #[derive(Debug, Clone)]
488        pub struct $elem {
489            $(
490            $(#[$attr_meta])*
491            pub $attr: $attr_type,
492            )*
493            $(
494            $(#[$child_meta])*
495            pub $child_ident: start_decl!($coucou, $child_type),
496            )*
497        }
498
499        impl ::try_from::TryFrom<::minidom::Element> for $elem {
500            type Err = ::error::Error;
501
502            fn try_from(elem: ::minidom::Element) -> Result<$elem, ::error::Error> {
503                check_self!(elem, $name, $ns);
504                check_no_unknown_attributes!(elem, $name, [$($attr_name),*]);
505                $(
506                start_parse_elem!($child_ident: $coucou);
507                )*
508                for _child in elem.children() {
509                    $(
510                    if _child.is($child_name, ::ns::$child_ns) {
511                        do_parse_elem!($child_ident: $coucou = $child_constructor => _child, $child_name, $name);
512                        continue;
513                    }
514                    )*
515                    return Err(::error::Error::ParseError(concat!("Unknown child in ", $name, " element.")));
516                }
517                Ok($elem {
518                    $(
519                    $attr: get_attr!(elem, $attr_name, $attr_action),
520                    )*
521                    $(
522                    $child_ident: finish_parse_elem!($child_ident: $coucou = $child_name, $name),
523                    )*
524                })
525            }
526        }
527
528        impl From<$elem> for ::minidom::Element {
529            fn from(elem: $elem) -> ::minidom::Element {
530                ::minidom::Element::builder($name)
531                        .ns(::ns::$ns)
532                        $(
533                        .attr($attr_name, elem.$attr)
534                        )*
535                        $(
536                        .append(generate_serialiser!(elem, $child_ident, $coucou, $child_constructor, ($child_name, $child_ns)))
537                        )*
538                        .build()
539            }
540        }
541    );
542}