strum_macros/helpers/
variant_props.rs

1use std::default::Default;
2use syn::{Ident, Lit, LitStr, Variant};
3
4use super::case_style::{CaseStyle, CaseStyleHelpers};
5use super::metadata::{kw, VariantExt, VariantMeta};
6use super::occurrence_error;
7
8pub trait HasStrumVariantProperties {
9    fn get_variant_properties(&self) -> syn::Result<StrumVariantProperties>;
10}
11
12#[derive(Clone, Default)]
13pub struct StrumVariantProperties {
14    pub transparent: Option<kw::transparent>,
15    pub disabled: Option<kw::disabled>,
16    pub default: Option<kw::default>,
17    pub default_with: Option<LitStr>,
18    pub ascii_case_insensitive: Option<bool>,
19    pub message: Option<LitStr>,
20    pub detailed_message: Option<LitStr>,
21    pub documentation: Vec<LitStr>,
22    pub props: Vec<(LitStr, Lit)>,
23    serialize: Vec<LitStr>,
24    pub to_string: Option<LitStr>,
25    ident: Option<Ident>,
26}
27
28impl StrumVariantProperties {
29    fn ident_as_str(&self, case_style: Option<CaseStyle>) -> LitStr {
30        let ident = self.ident.as_ref().expect("identifier");
31        LitStr::new(&ident.convert_case(case_style), ident.span())
32    }
33
34    pub fn get_preferred_name(
35        &self,
36        case_style: Option<CaseStyle>,
37        prefix: Option<&LitStr>,
38    ) -> LitStr {
39        let mut output = self.to_string.as_ref().cloned().unwrap_or_else(|| {
40            self.serialize
41                .iter()
42                .max_by_key(|s| s.value().len())
43                .cloned()
44                .unwrap_or_else(|| self.ident_as_str(case_style))
45        });
46
47        if let Some(prefix) = prefix {
48            output = LitStr::new(&(prefix.value() + &output.value()), output.span());
49        }
50
51        output
52    }
53
54    pub fn get_serializations(&self, case_style: Option<CaseStyle>) -> Vec<LitStr> {
55        let mut attrs = self.serialize.clone();
56        if let Some(to_string) = &self.to_string {
57            attrs.push(to_string.clone());
58        }
59
60        if attrs.is_empty() {
61            attrs.push(self.ident_as_str(case_style));
62        }
63
64        attrs
65    }
66}
67
68impl HasStrumVariantProperties for Variant {
69    fn get_variant_properties(&self) -> syn::Result<StrumVariantProperties> {
70        let mut output = StrumVariantProperties {
71            ident: Some(self.ident.clone()),
72            ..Default::default()
73        };
74
75        let mut message_kw = None;
76        let mut detailed_message_kw = None;
77        let mut transparent_kw = None;
78        let mut disabled_kw = None;
79        let mut default_kw = None;
80        let mut default_with_kw = None;
81        let mut to_string_kw = None;
82        let mut ascii_case_insensitive_kw = None;
83        for meta in self.get_metadata()? {
84            match meta {
85                VariantMeta::Message { value, kw } => {
86                    if let Some(fst_kw) = message_kw {
87                        return Err(occurrence_error(fst_kw, kw, "message"));
88                    }
89
90                    message_kw = Some(kw);
91                    output.message = Some(value);
92                }
93                VariantMeta::DetailedMessage { value, kw } => {
94                    if let Some(fst_kw) = detailed_message_kw {
95                        return Err(occurrence_error(fst_kw, kw, "detailed_message"));
96                    }
97
98                    detailed_message_kw = Some(kw);
99                    output.detailed_message = Some(value);
100                }
101                VariantMeta::Documentation { value } => {
102                    output.documentation.push(value);
103                }
104                VariantMeta::Serialize { value, .. } => {
105                    output.serialize.push(value);
106                }
107                VariantMeta::ToString { value, kw } => {
108                    if let Some(fst_kw) = to_string_kw {
109                        return Err(occurrence_error(fst_kw, kw, "to_string"));
110                    }
111
112                    to_string_kw = Some(kw);
113                    output.to_string = Some(value);
114                }
115                VariantMeta::Transparent(kw) => {
116                    if let Some(fst_kw) = transparent_kw {
117                        return Err(occurrence_error(fst_kw, kw, "transparent"));
118                    }
119
120                    transparent_kw = Some(kw);
121                    output.transparent = Some(kw);
122                }
123                VariantMeta::Disabled(kw) => {
124                    if let Some(fst_kw) = disabled_kw {
125                        return Err(occurrence_error(fst_kw, kw, "disabled"));
126                    }
127
128                    disabled_kw = Some(kw);
129                    output.disabled = Some(kw);
130                }
131                VariantMeta::Default(kw) => {
132                    if let Some(fst_kw) = default_kw {
133                        return Err(occurrence_error(fst_kw, kw, "default"));
134                    }
135
136                    default_kw = Some(kw);
137                    output.default = Some(kw);
138                }
139                VariantMeta::DefaultWith { kw, value } => {
140                    if let Some(fst_kw) = default_with_kw {
141                        return Err(occurrence_error(fst_kw, kw, "default_with"));
142                    }
143
144                    default_with_kw = Some(kw);
145                    output.default_with = Some(value);
146                }
147                VariantMeta::AsciiCaseInsensitive { kw, value } => {
148                    if let Some(fst_kw) = ascii_case_insensitive_kw {
149                        return Err(occurrence_error(fst_kw, kw, "ascii_case_insensitive"));
150                    }
151
152                    ascii_case_insensitive_kw = Some(kw);
153                    output.ascii_case_insensitive = Some(value);
154                }
155                VariantMeta::Props { props, .. } => {
156                    output.props.extend(props);
157                }
158            }
159        }
160
161        Ok(output)
162    }
163}
strum_macros/helpers/variant_props.rs

strum_macros/helpers/
variant_props.rs
