1use proc_macro::TokenStream;
2use quote::{format_ident, quote};
3use std::mem;
4use syn::{
5 parse_macro_input, parse_quote, spanned::Spanned as _, AttributeArgs, FnArg, ItemFn, Lit, Meta,
6 NestedMeta, Type,
7};
8
9#[proc_macro_attribute]
10pub fn test(args: TokenStream, function: TokenStream) -> TokenStream {
11 let mut namespace = format_ident!("gpui");
12
13 let args = syn::parse_macro_input!(args as AttributeArgs);
14 let mut max_retries = 0;
15 let mut num_iterations = 1;
16 let mut starting_seed = 0;
17
18 for arg in args {
19 match arg {
20 NestedMeta::Meta(Meta::Path(name))
21 if name.get_ident().map_or(false, |n| n == "self") =>
22 {
23 namespace = format_ident!("crate");
24 }
25 NestedMeta::Meta(Meta::NameValue(meta)) => {
26 let key_name = meta.path.get_ident().map(|i| i.to_string());
27 let result = (|| {
28 match key_name.as_ref().map(String::as_str) {
29 Some("retries") => max_retries = parse_int(&meta.lit)?,
30 Some("iterations") => num_iterations = parse_int(&meta.lit)?,
31 Some("seed") => starting_seed = parse_int(&meta.lit)?,
32 _ => {
33 return Err(TokenStream::from(
34 syn::Error::new(meta.path.span(), "invalid argument")
35 .into_compile_error(),
36 ))
37 }
38 }
39 Ok(())
40 })();
41
42 if let Err(tokens) = result {
43 return tokens;
44 }
45 }
46 other => {
47 return TokenStream::from(
48 syn::Error::new_spanned(other, "invalid argument").into_compile_error(),
49 )
50 }
51 }
52 }
53
54 let mut inner_fn = parse_macro_input!(function as ItemFn);
55 if max_retries > 0 && num_iterations > 1 {
56 return TokenStream::from(
57 syn::Error::new_spanned(inner_fn, "retries and randomized iterations can't be mixed")
58 .into_compile_error(),
59 );
60 }
61 let inner_fn_attributes = mem::take(&mut inner_fn.attrs);
62 let inner_fn_name = format_ident!("_{}", inner_fn.sig.ident);
63 let outer_fn_name = mem::replace(&mut inner_fn.sig.ident, inner_fn_name.clone());
64
65 let mut outer_fn: ItemFn = if inner_fn.sig.asyncness.is_some() {
66 // Pass to the test function the number of app contexts that it needs,
67 // based on its parameter list.
68 let mut inner_fn_args = proc_macro2::TokenStream::new();
69 for (ix, arg) in inner_fn.sig.inputs.iter().enumerate() {
70 if let FnArg::Typed(arg) = arg {
71 if let Type::Path(ty) = &*arg.ty {
72 let last_segment = ty.path.segments.last();
73 match last_segment.map(|s| s.ident.to_string()).as_deref() {
74 Some("TestAppContext") => {
75 let first_entity_id = ix * 100_000;
76 inner_fn_args.extend(quote!(
77 #namespace::TestAppContext::new(
78 foreground_platform.clone(),
79 platform.clone(),
80 foreground.clone(),
81 background.clone(),
82 font_cache.clone(),
83 #first_entity_id,
84 ),
85 ));
86 }
87 Some("StdRng") => {
88 inner_fn_args.extend(quote!(rand::SeedableRng::seed_from_u64(seed)));
89 }
90 _ => {
91 return TokenStream::from(
92 syn::Error::new_spanned(arg, "invalid argument")
93 .into_compile_error(),
94 )
95 }
96 }
97 } else {
98 return TokenStream::from(
99 syn::Error::new_spanned(arg, "invalid argument").into_compile_error(),
100 );
101 }
102 } else {
103 return TokenStream::from(
104 syn::Error::new_spanned(arg, "invalid argument").into_compile_error(),
105 );
106 }
107 }
108
109 parse_quote! {
110 #[test]
111 fn #outer_fn_name() {
112 #inner_fn
113
114 let is_randomized = #num_iterations > 1;
115 let mut num_iterations = #num_iterations as u64;
116 let mut starting_seed = #starting_seed as u64;
117 if is_randomized {
118 if let Ok(value) = std::env::var("SEED") {
119 starting_seed = value.parse().expect("invalid SEED variable");
120 }
121 if let Ok(value) = std::env::var("ITERATIONS") {
122 num_iterations = value.parse().expect("invalid ITERATIONS variable");
123 }
124 }
125
126 let mut atomic_seed = std::sync::atomic::AtomicU64::new(starting_seed as u64);
127 let mut retries = 0;
128
129 loop {
130 let result = std::panic::catch_unwind(|| {
131 let foreground_platform = std::rc::Rc::new(#namespace::platform::test::foreground_platform());
132 let platform = std::sync::Arc::new(#namespace::platform::test::platform());
133 let font_system = #namespace::Platform::fonts(platform.as_ref());
134 let font_cache = std::sync::Arc::new(#namespace::FontCache::new(font_system));
135
136 loop {
137 let seed = atomic_seed.load(std::sync::atomic::Ordering::SeqCst);
138 if seed >= starting_seed + num_iterations {
139 break;
140 }
141
142 if is_randomized {
143 dbg!(seed);
144 }
145
146 let (foreground, background) = #namespace::executor::deterministic(seed);
147 foreground.run(#inner_fn_name(#inner_fn_args));
148 atomic_seed.fetch_add(1, std::sync::atomic::Ordering::SeqCst);
149 }
150 });
151
152 match result {
153 Ok(result) => {
154 break;
155 }
156 Err(error) => {
157 if retries < #max_retries {
158 retries += 1;
159 println!("retrying: attempt {}", retries);
160 } else {
161 if is_randomized {
162 eprintln!("failing seed: {}", atomic_seed.load(std::sync::atomic::Ordering::SeqCst));
163 }
164 std::panic::resume_unwind(error);
165 }
166 }
167 }
168 }
169 }
170 }
171 } else {
172 let mut inner_fn_args = proc_macro2::TokenStream::new();
173 for arg in inner_fn.sig.inputs.iter() {
174 if let FnArg::Typed(arg) = arg {
175 if let Type::Path(ty) = &*arg.ty {
176 let last_segment = ty.path.segments.last();
177 if let Some("StdRng") = last_segment.map(|s| s.ident.to_string()).as_deref() {
178 inner_fn_args.extend(quote!(rand::SeedableRng::seed_from_u64(seed),));
179 }
180 } else {
181 inner_fn_args.extend(quote!(cx,));
182 }
183 } else {
184 return TokenStream::from(
185 syn::Error::new_spanned(arg, "invalid argument").into_compile_error(),
186 );
187 }
188 }
189
190 parse_quote! {
191 #[test]
192 fn #outer_fn_name() {
193 #inner_fn
194
195 let is_randomized = #num_iterations > 1;
196 let mut num_iterations = #num_iterations as u64;
197 let mut starting_seed = #starting_seed as u64;
198 if is_randomized {
199 if let Ok(value) = std::env::var("SEED") {
200 starting_seed = value.parse().expect("invalid SEED variable");
201 }
202 if let Ok(value) = std::env::var("ITERATIONS") {
203 num_iterations = value.parse().expect("invalid ITERATIONS variable");
204 }
205 }
206
207 let mut atomic_seed = std::sync::atomic::AtomicU64::new(starting_seed as u64);
208 let mut retries = 0;
209
210 loop {
211 let result = std::panic::catch_unwind(|| {
212 let foreground_platform = std::rc::Rc::new(#namespace::platform::test::foreground_platform());
213 let platform = std::sync::Arc::new(#namespace::platform::test::platform());
214 let font_system = #namespace::Platform::fonts(platform.as_ref());
215 let font_cache = std::sync::Arc::new(#namespace::FontCache::new(font_system));
216
217 loop {
218 let seed = atomic_seed.load(std::sync::atomic::Ordering::SeqCst);
219 if seed >= starting_seed + num_iterations {
220 break;
221 }
222
223 if is_randomized {
224 dbg!(seed);
225 }
226
227 let (foreground, background) = #namespace::executor::deterministic(seed);
228 let mut cx = #namespace::TestAppContext::new(
229 foreground_platform.clone(),
230 platform.clone(),
231 foreground.clone(),
232 background.clone(),
233 font_cache.clone(),
234 0,
235 );
236 cx.update(|cx| #inner_fn_name(#inner_fn_args));
237
238 atomic_seed.fetch_add(1, std::sync::atomic::Ordering::SeqCst);
239 }
240 });
241
242 match result {
243 Ok(_) => {
244 break;
245 }
246 Err(error) => {
247 if retries < #max_retries {
248 retries += 1;
249 println!("retrying: attempt {}", retries);
250 } else {
251 if is_randomized {
252 eprintln!("failing seed: {}", atomic_seed.load(std::sync::atomic::Ordering::SeqCst));
253 }
254 std::panic::resume_unwind(error);
255 }
256 }
257 }
258 }
259 }
260 }
261 };
262 outer_fn.attrs.extend(inner_fn_attributes);
263
264 TokenStream::from(quote!(#outer_fn))
265}
266
267fn parse_int(literal: &Lit) -> Result<usize, TokenStream> {
268 let result = if let Lit::Int(int) = &literal {
269 int.base10_parse()
270 } else {
271 Err(syn::Error::new(literal.span(), "must be an integer"))
272 };
273
274 result.map_err(|err| TokenStream::from(err.into_compile_error()))
275}