1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170

//LICENSE Portions Copyright 2019-2021 ZomboDB, LLC.
//LICENSE
//LICENSE Portions Copyright 2021-2023 Technology Concepts & Design, Inc.
//LICENSE
//LICENSE Portions Copyright 2023-2023 PgCentral Foundation, Inc. <contact@pgcentral.org>
//LICENSE
//LICENSE All rights reserved.
//LICENSE
//LICENSE Use of this source code is governed by the MIT license that can be found in the LICENSE file.
use crate::NameMacro;
use proc_macro2::TokenStream;

pub fn staticize_lifetimes_in_type_path(value: syn::TypePath) -> syn::TypePath {
    let mut ty = syn::Type::Path(value);
    staticize_lifetimes(&mut ty);
    match ty {
        syn::Type::Path(type_path) => type_path,

        // shouldn't happen
        _ => panic!("not a TypePath"),
    }
}

pub fn staticize_lifetimes(value: &mut syn::Type) {
    match value {
        syn::Type::Path(type_path) => {
            for segment in &mut type_path.path.segments {
                match &mut segment.arguments {
                    syn::PathArguments::AngleBracketed(bracketed) => {
                        for arg in &mut bracketed.args {
                            match arg {
                                // rename lifetimes to the static lifetime so the TypeIds match.
                                syn::GenericArgument::Lifetime(lifetime) => {
                                    lifetime.ident =
                                        syn::Ident::new("static", lifetime.ident.span());
                                }

                                // recurse
                                syn::GenericArgument::Type(ty) => staticize_lifetimes(ty),
                                syn::GenericArgument::Binding(binding) => {
                                    staticize_lifetimes(&mut binding.ty)
                                }
                                syn::GenericArgument::Constraint(constraint) => {
                                    for bound in constraint.bounds.iter_mut() {
                                        match bound {
                                            syn::TypeParamBound::Lifetime(lifetime) => {
                                                lifetime.ident =
                                                    syn::Ident::new("static", lifetime.ident.span())
                                            }
                                            _ => {}
                                        }
                                    }
                                }

                                // nothing to do otherwise
                                _ => {}
                            }
                        }
                    }
                    _ => {}
                }
            }
        }

        syn::Type::Reference(type_ref) => match &mut type_ref.lifetime {
            Some(ref mut lifetime) => {
                lifetime.ident = syn::Ident::new("static", lifetime.ident.span());
            }
            this @ None => *this = Some(syn::parse_quote!('static)),
        },

        syn::Type::Tuple(type_tuple) => {
            for elem in &mut type_tuple.elems {
                staticize_lifetimes(elem);
            }
        }

        syn::Type::Macro(type_macro) => {
            let mac = &type_macro.mac;
            if let Some(archetype) = mac.path.segments.last() {
                match archetype.ident.to_string().as_str() {
                    "name" => {
                        if let Ok(out) = mac.parse_body::<NameMacro>() {
                            // We don't particularly care what the identifier is, so we parse a
                            // raw TokenStream.  Specifically, it's okay for the identifier String,
                            // which we end up using as a Postgres column name, to be nearly any
                            // string, which can include Rust reserved words such as "type" or "match"
                            if let Ok(ident) = syn::parse_str::<TokenStream>(&out.ident) {
                                let mut ty = out.used_ty.resolved_ty;

                                // rewrite the name!() macro's type so that it has a static lifetime, if any
                                staticize_lifetimes(&mut ty);
                                type_macro.mac = syn::parse_quote! {::pgrx::name!(#ident, #ty)};
                            }
                        }
                    }
                    _ => {}
                }
            }
        }
        _ => {}
    }
}

pub fn anonymize_lifetimes_in_type_path(value: syn::TypePath) -> syn::TypePath {
    let mut ty = syn::Type::Path(value);
    anonymize_lifetimes(&mut ty);
    match ty {
        syn::Type::Path(type_path) => type_path,

        // shouldn't happen
        _ => panic!("not a TypePath"),
    }
}

pub fn anonymize_lifetimes(value: &mut syn::Type) {
    match value {
        syn::Type::Path(type_path) => {
            for segment in &mut type_path.path.segments {
                match &mut segment.arguments {
                    syn::PathArguments::AngleBracketed(bracketed) => {
                        for arg in &mut bracketed.args {
                            match arg {
                                // rename lifetimes to the anonymous lifetime
                                syn::GenericArgument::Lifetime(lifetime) => {
                                    lifetime.ident = syn::Ident::new("_", lifetime.ident.span());
                                }

                                // recurse
                                syn::GenericArgument::Type(ty) => anonymize_lifetimes(ty),
                                syn::GenericArgument::Binding(binding) => {
                                    anonymize_lifetimes(&mut binding.ty)
                                }
                                syn::GenericArgument::Constraint(constraint) => {
                                    for bound in constraint.bounds.iter_mut() {
                                        match bound {
                                            syn::TypeParamBound::Lifetime(lifetime) => {
                                                lifetime.ident =
                                                    syn::Ident::new("_", lifetime.ident.span())
                                            }
                                            _ => {}
                                        }
                                    }
                                }

                                // nothing to do otherwise
                                _ => {}
                            }
                        }
                    }
                    _ => {}
                }
            }
        }

        syn::Type::Reference(type_ref) => {
            if let Some(lifetime) = type_ref.lifetime.as_mut() {
                lifetime.ident = syn::Ident::new("_", lifetime.ident.span());
            }
        }

        syn::Type::Tuple(type_tuple) => {
            for elem in &mut type_tuple.elems {
                anonymize_lifetimes(elem);
            }
        }

        _ => {}
    }
}