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::$ns)
282                        .build()
283            }
284        }
285    );
286}
287
288macro_rules! generate_element_with_only_attributes {
289    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident, [$($(#[$attr_meta:meta])* $attr:ident: $attr_type:ty = $attr_name:tt => $attr_action:tt),+,]) => (
290        generate_element_with_children!($(#[$meta])* $elem, $name, $ns, attributes: [$($(#[$attr_meta])* $attr: $attr_type = $attr_name => $attr_action),*], children: []);
291    );
292    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident, [$($(#[$attr_meta:meta])* $attr:ident: $attr_type:ty = $attr_name:tt => $attr_action:tt),+]) => (
293        generate_element_with_children!($(#[$meta])* $elem, $name, $ns, attributes: [$($(#[$attr_meta])* $attr: $attr_type = $attr_name => $attr_action),*], children: []);
294    );
295}
296
297macro_rules! generate_id {
298    ($elem:ident) => (
299        #[derive(Debug, Clone, PartialEq, Eq, Hash)]
300        pub struct $elem(pub String);
301        impl ::std::str::FromStr for $elem {
302            type Err = ::error::Error;
303            fn from_str(s: &str) -> Result<$elem, ::error::Error> {
304                // TODO: add a way to parse that differently when needed.
305                Ok($elem(String::from(s)))
306            }
307        }
308        impl ::minidom::IntoAttributeValue for $elem {
309            fn into_attribute_value(self) -> Option<String> {
310                Some(self.0)
311            }
312        }
313    );
314}
315
316macro_rules! generate_elem_id {
317    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident) => (
318        $(#[$meta])*
319        #[derive(Debug, Clone, PartialEq, Eq, Hash)]
320        pub struct $elem(pub String);
321        impl ::std::str::FromStr for $elem {
322            type Err = ::error::Error;
323            fn from_str(s: &str) -> Result<$elem, ::error::Error> {
324                // TODO: add a way to parse that differently when needed.
325                Ok($elem(String::from(s)))
326            }
327        }
328        impl ::try_from::TryFrom<::minidom::Element> for $elem {
329            type Err = ::error::Error;
330            fn try_from(elem: ::minidom::Element) -> Result<$elem, ::error::Error> {
331                check_self!(elem, $name, $ns);
332                check_no_children!(elem, $name);
333                check_no_attributes!(elem, $name);
334                // TODO: add a way to parse that differently when needed.
335                Ok($elem(elem.text()))
336            }
337        }
338        impl From<$elem> for ::minidom::Element {
339            fn from(elem: $elem) -> ::minidom::Element {
340                ::minidom::Element::builder($name)
341                        .ns(::ns::$ns)
342                        .append(elem.0)
343                        .build()
344            }
345        }
346    );
347}
348
349macro_rules! generate_element_with_text {
350    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident, $text_ident:ident: $codec:ident < $text_type:ty >) => (
351        generate_element_with_text!($(#[$meta])* $elem, $name, $ns, [], $text_ident: $codec<$text_type>);
352    );
353    ($(#[$meta:meta])* $elem:ident, $name:tt, $ns:ident, [$($(#[$attr_meta:meta])* $attr:ident: $attr_type:ty = $attr_name:tt => $attr_action:tt),*], $text_ident:ident: $codec:ident < $text_type:ty >) => (
354        $(#[$meta])*
355        #[derive(Debug, Clone)]
356        pub struct $elem {
357            $(
358            $(#[$attr_meta])*
359            pub $attr: $attr_type,
360            )*
361            pub $text_ident: $text_type,
362        }
363
364        impl ::try_from::TryFrom<::minidom::Element> for $elem {
365            type Err = ::error::Error;
366
367            fn try_from(elem: ::minidom::Element) -> Result<$elem, ::error::Error> {
368                check_self!(elem, $name, $ns);
369                check_no_children!(elem, $name);
370                check_no_unknown_attributes!(elem, $name, [$($attr_name),*]);
371                Ok($elem {
372                    $(
373                    $attr: get_attr!(elem, $attr_name, $attr_action),
374                    )*
375                    $text_ident: $codec::decode(&elem.text())?,
376                })
377            }
378        }
379
380        impl From<$elem> for ::minidom::Element {
381            fn from(elem: $elem) -> ::minidom::Element {
382                ::minidom::Element::builder($name)
383                        .ns(::ns::$ns)
384                        $(
385                        .attr($attr_name, elem.$attr)
386                        )*
387                        .append($codec::encode(&elem.$text_ident))
388                        .build()
389            }
390        }
391    );
392}
393
394macro_rules! start_decl {
395    (Vec, $type:ty) => (
396        Vec<$type>
397    );
398    (Option, $type:ty) => (
399        Option<$type>
400    );
401    (Required, $type:ty) => (
402        $type
403    );
404}
405
406macro_rules! start_parse_elem {
407    ($temp:ident: Vec) => (
408        let mut $temp = Vec::new();
409    );
410    ($temp:ident: Option) => (
411        let mut $temp = None;
412    );
413    ($temp:ident: Required) => (
414        let mut $temp = None;
415    );
416}
417
418macro_rules! do_parse {
419    ($elem:ident, Element) => (
420        $elem.clone()
421    );
422    ($elem:ident, String) => (
423        $elem.text()
424    );
425    ($elem:ident, $constructor:ident) => (
426        $constructor::try_from($elem.clone())?
427    );
428}
429
430macro_rules! do_parse_elem {
431    ($temp:ident: Vec = $constructor:ident => $elem:ident) => (
432        $temp.push(do_parse!($elem, $constructor));
433    );
434    ($temp:ident: Option = $constructor:ident => $elem:ident) => (
435        if $temp.is_some() {
436            return Err(::error::Error::ParseError(concat!("coucou", " must not have more than one ", "coucou", ".")));
437        }
438        $temp = Some(do_parse!($elem, $constructor));
439    );
440    ($temp:ident: Required = $constructor:ident => $elem:ident) => (
441        $temp = Some(do_parse!($elem, $constructor));
442    );
443}
444
445macro_rules! finish_parse_elem {
446    ($temp:ident: Vec = $name:tt) => (
447        $temp
448    );
449    ($temp:ident: Option = $name:tt) => (
450        $temp
451    );
452    ($temp:ident: Required = $name:tt) => (
453        $temp.ok_or(::error::Error::ParseError(concat!("Missing child coucou in ", $name, " element.")))?
454    );
455}
456
457macro_rules! generate_serialiser {
458    ($parent:ident, $elem:ident, Required, String, ($name:tt, $ns:ident)) => (
459        ::minidom::Element::builder($name)
460            .ns(::ns::$ns)
461            .append($parent.$elem)
462            .build()
463    );
464    ($parent:ident, $elem:ident, Option, String, ($name:tt, $ns:ident)) => (
465        $parent.$elem.map(|elem|
466            ::minidom::Element::builder($name)
467                .ns(::ns::$ns)
468                .append(elem)
469                .build())
470    );
471    ($parent:ident, $elem:ident, $_:ident, $constructor:ident, ($name:tt, $ns:ident)) => (
472        $parent.$elem
473    );
474}
475
476macro_rules! generate_element_with_children {
477    ($(#[$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) => $child_constructor:ident),*]) => (
478        generate_element_with_children!($(#[$meta])* $elem, $name, $ns, attributes: [], children: [$($(#[$child_meta])* $child_ident: $coucou<$child_type> = ($child_name, $child_ns) => $child_constructor),*]);
479    );
480    ($(#[$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) => $child_constructor:ident),*]) => (
481        generate_element_with_children!($(#[$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) => $child_constructor),*]);
482    );
483    ($(#[$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),*]) => (
484        $(#[$meta])*
485        #[derive(Debug, Clone)]
486        pub struct $elem {
487            $(
488            $(#[$attr_meta])*
489            pub $attr: $attr_type,
490            )*
491            $(
492            $(#[$child_meta])*
493            pub $child_ident: start_decl!($coucou, $child_type),
494            )*
495        }
496
497        impl ::try_from::TryFrom<::minidom::Element> for $elem {
498            type Err = ::error::Error;
499
500            fn try_from(elem: ::minidom::Element) -> Result<$elem, ::error::Error> {
501                check_self!(elem, $name, $ns);
502                check_no_unknown_attributes!(elem, $name, [$($attr_name),*]);
503                $(
504                start_parse_elem!($child_ident: $coucou);
505                )*
506                for _child in elem.children() {
507                    $(
508                    if _child.is($child_name, ::ns::$child_ns) {
509                        do_parse_elem!($child_ident: $coucou = $child_constructor => _child);
510                        continue;
511                    }
512                    )*
513                    return Err(::error::Error::ParseError(concat!("Unknown child in ", $name, " element.")));
514                }
515                Ok($elem {
516                    $(
517                    $attr: get_attr!(elem, $attr_name, $attr_action),
518                    )*
519                    $(
520                    $child_ident: finish_parse_elem!($child_ident: $coucou = $child_name),
521                    )*
522                })
523            }
524        }
525
526        impl From<$elem> for ::minidom::Element {
527            fn from(elem: $elem) -> ::minidom::Element {
528                ::minidom::Element::builder($name)
529                        .ns(::ns::$ns)
530                        $(
531                        .attr($attr_name, elem.$attr)
532                        )*
533                        $(
534                        .append(generate_serialiser!(elem, $child_ident, $coucou, $child_constructor, ($child_name, $child_ns)))
535                        )*
536                        .build()
537            }
538        }
539    );
540}