1 // Code that generates a test runner to run all the tests in a crate
4 #![allow(unused_imports)]
6 use self::HasTestSignature::*;
12 use attr::{self, HasAttrs};
13 use syntax_pos::{self, DUMMY_SP, NO_EXPANSION, Span, SourceFile, BytePos};
15 use source_map::{self, SourceMap, ExpnInfo, MacroAttribute, dummy_spanned, respan};
18 use entry::{self, EntryPointType};
19 use ext::base::{ExtCtxt, Resolver};
20 use ext::build::AstBuilder;
21 use ext::expand::ExpansionConfig;
22 use ext::hygiene::{self, Mark, SyntaxContext};
24 use feature_gate::Features;
25 use util::move_map::MoveMap;
26 use fold::{self, ExpectOne};
27 use parse::{token, ParseSess};
29 use ast::{self, Ident};
31 use smallvec::SmallVec;
32 use symbol::{self, Symbol, keywords};
41 span_diagnostic: &'a errors::Handler,
44 test_cases: Vec<Test>,
45 reexport_test_harness_main: Option<Symbol>,
48 features: &'a Features,
49 test_runner: Option<ast::Path>,
51 // top-level re-export submodule, filled out after folding is finished
52 toplevel_reexport: Option<Ident>,
55 // Traverse the crate, collecting all the test functions, eliding any
56 // existing main functions, and synthesizing a main test harness
57 pub fn modify_for_testing(sess: &ParseSess,
58 resolver: &mut dyn Resolver,
61 span_diagnostic: &errors::Handler,
62 features: &Features) -> ast::Crate {
63 // Check for #[reexport_test_harness_main = "some_name"] which
64 // creates a `use __test::main as some_name;`. This needs to be
65 // unconditional, so that the attribute is still marked as used in
67 let reexport_test_harness_main =
68 attr::first_attr_value_str_by_name(&krate.attrs,
69 "reexport_test_harness_main");
71 // Do this here so that the test_runner crate attribute gets marked as used
72 // even in non-test builds
73 let test_runner = get_test_runner(span_diagnostic, &krate);
76 generate_test_harness(sess, resolver, reexport_test_harness_main,
77 krate, span_diagnostic, features, test_runner)
83 struct TestHarnessGenerator<'a> {
87 // submodule name, gensym'd identifier for re-exports
88 tested_submods: Vec<(Ident, Ident)>,
91 impl<'a> fold::Folder for TestHarnessGenerator<'a> {
92 fn fold_crate(&mut self, c: ast::Crate) -> ast::Crate {
93 let mut folded = fold::noop_fold_crate(c, self);
95 // Create a main function to run our tests
97 let unresolved = mk_main(&mut self.cx);
98 self.cx.ext_cx.monotonic_expander().fold_item(unresolved).pop().unwrap()
101 folded.module.items.push(test_main);
105 fn fold_item(&mut self, i: P<ast::Item>) -> SmallVec<[P<ast::Item>; 1]> {
107 if ident.name != keywords::Invalid.name() {
108 self.cx.path.push(ident);
110 debug!("current path: {}", path_name_i(&self.cx.path));
112 let mut item = i.into_inner();
113 if is_test_case(&item) {
114 debug!("this is a test item");
118 path: self.cx.path.clone(),
120 self.cx.test_cases.push(test);
121 self.tests.push(item.ident);
124 // We don't want to recurse into anything other than mods, since
125 // mods or tests inside of functions will break things
126 if let ast::ItemKind::Mod(module) = item.node {
127 let tests = mem::replace(&mut self.tests, Vec::new());
128 let tested_submods = mem::replace(&mut self.tested_submods, Vec::new());
129 let mut mod_folded = fold::noop_fold_mod(module, self);
130 let tests = mem::replace(&mut self.tests, tests);
131 let tested_submods = mem::replace(&mut self.tested_submods, tested_submods);
133 if !tests.is_empty() || !tested_submods.is_empty() {
134 let (it, sym) = mk_reexport_mod(&mut self.cx, item.id, tests, tested_submods);
135 mod_folded.items.push(it);
137 if !self.cx.path.is_empty() {
138 self.tested_submods.push((self.cx.path[self.cx.path.len()-1], sym));
140 debug!("pushing nothing, sym: {:?}", sym);
141 self.cx.toplevel_reexport = Some(sym);
144 item.node = ast::ItemKind::Mod(mod_folded);
146 if ident.name != keywords::Invalid.name() {
152 fn fold_mac(&mut self, mac: ast::Mac) -> ast::Mac { mac }
155 /// A folder used to remove any entry points (like fn main) because the harness
156 /// generator will provide its own
157 struct EntryPointCleaner {
158 // Current depth in the ast
162 impl fold::Folder for EntryPointCleaner {
163 fn fold_item(&mut self, i: P<ast::Item>) -> SmallVec<[P<ast::Item>; 1]> {
165 let folded = fold::noop_fold_item(i, self).expect_one("noop did something");
168 // Remove any #[main] or #[start] from the AST so it doesn't
169 // clash with the one we're going to add, but mark it as
170 // #[allow(dead_code)] to avoid printing warnings.
171 let folded = match entry::entry_point_type(&folded, self.depth) {
172 EntryPointType::MainNamed |
173 EntryPointType::MainAttr |
174 EntryPointType::Start =>
175 folded.map(|ast::Item {id, ident, attrs, node, vis, span, tokens}| {
176 let allow_ident = Ident::from_str("allow");
177 let dc_nested = attr::mk_nested_word_item(Ident::from_str("dead_code"));
178 let allow_dead_code_item = attr::mk_list_item(DUMMY_SP, allow_ident,
180 let allow_dead_code = attr::mk_attr_outer(DUMMY_SP,
182 allow_dead_code_item);
187 attrs: attrs.into_iter()
189 !attr.check_name("main") && !attr.check_name("start")
191 .chain(iter::once(allow_dead_code))
199 EntryPointType::None |
200 EntryPointType::OtherMain => folded,
206 fn fold_mac(&mut self, mac: ast::Mac) -> ast::Mac { mac }
209 /// Creates an item (specifically a module) that "pub use"s the tests passed in.
210 /// Each tested submodule will contain a similar reexport module that we will export
211 /// under the name of the original module. That is, `submod::__test_reexports` is
212 /// reexported like so `pub use submod::__test_reexports as submod`.
213 fn mk_reexport_mod(cx: &mut TestCtxt,
216 tested_submods: Vec<(Ident, Ident)>)
217 -> (P<ast::Item>, Ident) {
218 let super_ = Ident::from_str("super");
220 let items = tests.into_iter().map(|r| {
221 cx.ext_cx.item_use_simple(DUMMY_SP, dummy_spanned(ast::VisibilityKind::Public),
222 cx.ext_cx.path(DUMMY_SP, vec![super_, r]))
223 }).chain(tested_submods.into_iter().map(|(r, sym)| {
224 let path = cx.ext_cx.path(DUMMY_SP, vec![super_, r, sym]);
225 cx.ext_cx.item_use_simple_(DUMMY_SP, dummy_spanned(ast::VisibilityKind::Public),
229 let reexport_mod = ast::Mod {
235 let sym = Ident::with_empty_ctxt(Symbol::gensym("__test_reexports"));
236 let parent = if parent == ast::DUMMY_NODE_ID { ast::CRATE_NODE_ID } else { parent };
237 cx.ext_cx.current_expansion.mark = cx.ext_cx.resolver.get_module_scope(parent);
238 let it = cx.ext_cx.monotonic_expander().fold_item(P(ast::Item {
241 id: ast::DUMMY_NODE_ID,
242 node: ast::ItemKind::Mod(reexport_mod),
243 vis: dummy_spanned(ast::VisibilityKind::Public),
251 /// Crawl over the crate, inserting test reexports and the test main function
252 fn generate_test_harness(sess: &ParseSess,
253 resolver: &mut dyn Resolver,
254 reexport_test_harness_main: Option<Symbol>,
256 sd: &errors::Handler,
258 test_runner: Option<ast::Path>) -> ast::Crate {
259 // Remove the entry points
260 let mut cleaner = EntryPointCleaner { depth: 0 };
261 let krate = cleaner.fold_crate(krate);
263 let mark = Mark::fresh(Mark::root());
265 let mut econfig = ExpansionConfig::default("test".to_string());
266 econfig.features = Some(features);
270 ext_cx: ExtCtxt::new(sess, econfig, resolver),
272 test_cases: Vec::new(),
273 reexport_test_harness_main,
274 // N.B., doesn't consider the value of `--crate-name` passed on the command line.
275 is_libtest: attr::find_crate_name(&krate.attrs).map(|s| s == "test").unwrap_or(false),
276 toplevel_reexport: None,
277 ctxt: SyntaxContext::empty().apply_mark(mark),
282 mark.set_expn_info(ExpnInfo {
285 format: MacroAttribute(Symbol::intern("test_case")),
286 allow_internal_unstable: true,
287 allow_internal_unsafe: false,
288 local_inner_macros: false,
289 edition: hygiene::default_edition(),
292 TestHarnessGenerator {
295 tested_submods: Vec::new(),
299 /// Craft a span that will be ignored by the stability lint's
300 /// call to source_map's `is_internal` check.
301 /// The expanded code calls some unstable functions in the test crate.
302 fn ignored_span(cx: &TestCtxt, sp: Span) -> Span {
303 sp.with_ctxt(cx.ctxt)
306 enum HasTestSignature {
308 No(BadTestSignature),
312 enum BadTestSignature {
316 ShouldPanicOnlyWithNoArgs,
319 /// Creates a function item for use as the main function of a test build.
320 /// This function will call the `test_runner` as specified by the crate attribute
321 fn mk_main(cx: &mut TestCtxt) -> P<ast::Item> {
322 // Writing this out by hand with 'ignored_span':
325 // test::test_main_static(::std::os::args().as_slice(), &[..tests]);
327 let sp = ignored_span(cx, DUMMY_SP);
328 let ecx = &cx.ext_cx;
329 let test_id = ecx.ident_of("test").gensym();
331 // test::test_main_static(...)
332 let mut test_runner = cx.test_runner.clone().unwrap_or(
334 test_id, ecx.ident_of("test_main_static")
337 test_runner.span = sp;
339 let test_main_path_expr = ecx.expr_path(test_runner);
340 let call_test_main = ecx.expr_call(sp, test_main_path_expr,
341 vec![mk_tests_slice(cx)]);
342 let call_test_main = ecx.stmt_expr(call_test_main);
345 let main_meta = ecx.meta_word(sp, Symbol::intern("main"));
346 let main_attr = ecx.attribute(sp, main_meta);
348 // extern crate test as test_gensym
349 let test_extern_stmt = ecx.stmt_item(sp, ecx.item(sp,
352 ast::ItemKind::ExternCrate(Some(Symbol::intern("test")))
355 // pub fn main() { ... }
356 let main_ret_ty = ecx.ty(sp, ast::TyKind::Tup(vec![]));
358 // If no test runner is provided we need to import the test crate
359 let main_body = if cx.test_runner.is_none() {
360 ecx.block(sp, vec![test_extern_stmt, call_test_main])
362 ecx.block(sp, vec![call_test_main])
365 let main = ast::ItemKind::Fn(ecx.fn_decl(vec![], ast::FunctionRetTy::Ty(main_ret_ty)),
366 ast::FnHeader::default(),
367 ast::Generics::default(),
370 // Honor the reexport_test_harness_main attribute
371 let main_id = Ident::new(
372 cx.reexport_test_harness_main.unwrap_or(Symbol::gensym("main")),
377 attrs: vec![main_attr],
378 id: ast::DUMMY_NODE_ID,
380 vis: dummy_spanned(ast::VisibilityKind::Public),
387 fn path_name_i(idents: &[Ident]) -> String {
388 let mut path_name = "".to_string();
389 let mut idents_iter = idents.iter().peekable();
390 while let Some(ident) = idents_iter.next() {
391 path_name.push_str(&ident.as_str());
392 if idents_iter.peek().is_some() {
393 path_name.push_str("::")
399 /// Creates a slice containing every test like so:
400 /// &[path::to::test1, path::to::test2]
401 fn mk_tests_slice(cx: &TestCtxt) -> P<ast::Expr> {
402 debug!("building test vector from {} tests", cx.test_cases.len());
403 let ref ecx = cx.ext_cx;
405 ecx.expr_vec_slice(DUMMY_SP,
406 cx.test_cases.iter().map(|test| {
407 ecx.expr_addr_of(test.span,
408 ecx.expr_path(ecx.path(test.span, visible_path(cx, &test.path))))
412 /// Creates a path from the top-level __test module to the test via __test_reexports
413 fn visible_path(cx: &TestCtxt, path: &[Ident]) -> Vec<Ident>{
414 let mut visible_path = vec![];
415 match cx.toplevel_reexport {
416 Some(id) => visible_path.push(id),
418 cx.span_diagnostic.bug("expected to find top-level re-export name, but found None");
421 visible_path.extend_from_slice(path);
425 fn is_test_case(i: &ast::Item) -> bool {
426 attr::contains_name(&i.attrs, "rustc_test_marker")
429 fn get_test_runner(sd: &errors::Handler, krate: &ast::Crate) -> Option<ast::Path> {
430 let test_attr = attr::find_by_name(&krate.attrs, "test_runner")?;
431 if let Some(meta_list) = test_attr.meta_item_list() {
432 if meta_list.len() != 1 {
433 sd.span_fatal(test_attr.span(),
434 "#![test_runner(..)] accepts exactly 1 argument").raise()
436 Some(meta_list[0].word().as_ref().unwrap().ident.clone())
438 sd.span_fatal(test_attr.span(),
439 "test_runner must be of the form #[test_runner(..)]").raise()