rust/src/libsyntax/test.rs
2014-12-14 11:11:55 -05:00

611 lines
20 KiB
Rust

// Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// Code that generates a test runner to run all the tests in a crate
#![allow(dead_code)]
#![allow(unused_imports)]
use self::HasTestSignature::*;
use std::slice;
use std::mem;
use std::vec;
use ast_util::*;
use attr::AttrMetaMethods;
use attr;
use codemap::{DUMMY_SP, Span, ExpnInfo, NameAndSpan, MacroAttribute};
use codemap;
use diagnostic;
use config;
use ext::base::ExtCtxt;
use ext::build::AstBuilder;
use ext::expand::ExpansionConfig;
use fold::{Folder, MoveMap};
use fold;
use owned_slice::OwnedSlice;
use parse::token::InternedString;
use parse::{token, ParseSess};
use print::pprust;
use {ast, ast_util};
use ptr::P;
use util::small_vector::SmallVector;
enum ShouldFail {
No,
Yes(Option<InternedString>),
}
struct Test {
span: Span,
path: Vec<ast::Ident> ,
bench: bool,
ignore: bool,
should_fail: ShouldFail
}
struct TestCtxt<'a> {
sess: &'a ParseSess,
span_diagnostic: &'a diagnostic::SpanHandler,
path: Vec<ast::Ident>,
ext_cx: ExtCtxt<'a>,
testfns: Vec<Test>,
reexport_test_harness_main: Option<InternedString>,
is_test_crate: bool,
config: ast::CrateConfig,
// top-level re-export submodule, filled out after folding is finished
toplevel_reexport: Option<ast::Ident>,
}
// Traverse the crate, collecting all the test functions, eliding any
// existing main functions, and synthesizing a main test harness
pub fn modify_for_testing(sess: &ParseSess,
cfg: &ast::CrateConfig,
krate: ast::Crate,
span_diagnostic: &diagnostic::SpanHandler) -> ast::Crate {
// We generate the test harness when building in the 'test'
// configuration, either with the '--test' or '--cfg test'
// command line options.
let should_test = attr::contains_name(krate.config.as_slice(), "test");
// Check for #[reexport_test_harness_main = "some_name"] which
// creates a `use some_name = __test::main;`. This needs to be
// unconditional, so that the attribute is still marked as used in
// non-test builds.
let reexport_test_harness_main =
attr::first_attr_value_str_by_name(krate.attrs.as_slice(),
"reexport_test_harness_main");
if should_test {
generate_test_harness(sess, reexport_test_harness_main, krate, cfg, span_diagnostic)
} else {
strip_test_functions(krate)
}
}
struct TestHarnessGenerator<'a> {
cx: TestCtxt<'a>,
tests: Vec<ast::Ident>,
// submodule name, gensym'd identifier for re-exports
tested_submods: Vec<(ast::Ident, ast::Ident)>,
}
impl<'a> fold::Folder for TestHarnessGenerator<'a> {
fn fold_crate(&mut self, c: ast::Crate) -> ast::Crate {
let mut folded = fold::noop_fold_crate(c, self);
// Add a special __test module to the crate that will contain code
// generated for the test harness
let (mod_, reexport) = mk_test_module(&mut self.cx);
folded.module.items.push(mod_);
match reexport {
Some(re) => folded.module.view_items.push(re),
None => {}
}
folded
}
fn fold_item(&mut self, i: P<ast::Item>) -> SmallVector<P<ast::Item>> {
let ident = i.ident;
if ident.name != token::special_idents::invalid.name {
self.cx.path.push(ident);
}
debug!("current path: {}",
ast_util::path_name_i(self.cx.path.as_slice()));
if is_test_fn(&self.cx, &*i) || is_bench_fn(&self.cx, &*i) {
match i.node {
ast::ItemFn(_, ast::Unsafety::Unsafe, _, _, _) => {
let diag = self.cx.span_diagnostic;
diag.span_fatal(i.span,
"unsafe functions cannot be used for \
tests");
}
_ => {
debug!("this is a test function");
let test = Test {
span: i.span,
path: self.cx.path.clone(),
bench: is_bench_fn(&self.cx, &*i),
ignore: is_ignored(&*i),
should_fail: should_fail(&*i)
};
self.cx.testfns.push(test);
self.tests.push(i.ident);
// debug!("have {} test/bench functions",
// cx.testfns.len());
}
}
}
// We don't want to recurse into anything other than mods, since
// mods or tests inside of functions will break things
let res = match i.node {
ast::ItemMod(..) => fold::noop_fold_item(i, self),
_ => SmallVector::one(i),
};
if ident.name != token::special_idents::invalid.name {
self.cx.path.pop();
}
res
}
fn fold_mod(&mut self, m: ast::Mod) -> ast::Mod {
let tests = mem::replace(&mut self.tests, Vec::new());
let tested_submods = mem::replace(&mut self.tested_submods, Vec::new());
let mut mod_folded = fold::noop_fold_mod(m, self);
let tests = mem::replace(&mut self.tests, tests);
let tested_submods = mem::replace(&mut self.tested_submods, tested_submods);
// Remove any #[main] from the AST so it doesn't clash with
// the one we're going to add. Only if compiling an executable.
mod_folded.items = mem::replace(&mut mod_folded.items, vec![]).move_map(|item| {
item.map(|ast::Item {id, ident, attrs, node, vis, span}| {
ast::Item {
id: id,
ident: ident,
attrs: attrs.into_iter().filter_map(|attr| {
if !attr.check_name("main") {
Some(attr)
} else {
None
}
}).collect(),
node: node,
vis: vis,
span: span
}
})
});
if !tests.is_empty() || !tested_submods.is_empty() {
let (it, sym) = mk_reexport_mod(&mut self.cx, tests, tested_submods);
mod_folded.items.push(it);
if !self.cx.path.is_empty() {
self.tested_submods.push((self.cx.path[self.cx.path.len()-1], sym));
} else {
debug!("pushing nothing, sym: {}", sym);
self.cx.toplevel_reexport = Some(sym);
}
}
mod_folded
}
}
fn mk_reexport_mod(cx: &mut TestCtxt, tests: Vec<ast::Ident>,
tested_submods: Vec<(ast::Ident, ast::Ident)>) -> (P<ast::Item>, ast::Ident) {
let mut view_items = Vec::new();
let super_ = token::str_to_ident("super");
view_items.extend(tests.into_iter().map(|r| {
cx.ext_cx.view_use_simple(DUMMY_SP, ast::Public,
cx.ext_cx.path(DUMMY_SP, vec![super_, r]))
}));
view_items.extend(tested_submods.into_iter().map(|(r, sym)| {
let path = cx.ext_cx.path(DUMMY_SP, vec![super_, r, sym]);
cx.ext_cx.view_use_simple_(DUMMY_SP, ast::Public, r, path)
}));
let reexport_mod = ast::Mod {
inner: DUMMY_SP,
view_items: view_items,
items: Vec::new(),
};
let sym = token::gensym_ident("__test_reexports");
let it = P(ast::Item {
ident: sym.clone(),
attrs: Vec::new(),
id: ast::DUMMY_NODE_ID,
node: ast::ItemMod(reexport_mod),
vis: ast::Public,
span: DUMMY_SP,
});
(it, sym)
}
fn generate_test_harness(sess: &ParseSess,
reexport_test_harness_main: Option<InternedString>,
krate: ast::Crate,
cfg: &ast::CrateConfig,
sd: &diagnostic::SpanHandler) -> ast::Crate {
let mut cx: TestCtxt = TestCtxt {
sess: sess,
span_diagnostic: sd,
ext_cx: ExtCtxt::new(sess, cfg.clone(),
ExpansionConfig::default("test".to_string())),
path: Vec::new(),
testfns: Vec::new(),
reexport_test_harness_main: reexport_test_harness_main,
is_test_crate: is_test_crate(&krate),
config: krate.config.clone(),
toplevel_reexport: None,
};
cx.ext_cx.bt_push(ExpnInfo {
call_site: DUMMY_SP,
callee: NameAndSpan {
name: "test".to_string(),
format: MacroAttribute,
span: None
}
});
let mut fold = TestHarnessGenerator {
cx: cx,
tests: Vec::new(),
tested_submods: Vec::new(),
};
let res = fold.fold_crate(krate);
fold.cx.ext_cx.bt_pop();
return res;
}
fn strip_test_functions(krate: ast::Crate) -> ast::Crate {
// When not compiling with --test we should not compile the
// #[test] functions
config::strip_items(krate, |attrs| {
!attr::contains_name(attrs.as_slice(), "test") &&
!attr::contains_name(attrs.as_slice(), "bench")
})
}
#[deriving(PartialEq)]
enum HasTestSignature {
Yes,
No,
NotEvenAFunction,
}
fn is_test_fn(cx: &TestCtxt, i: &ast::Item) -> bool {
let has_test_attr = attr::contains_name(i.attrs.as_slice(), "test");
fn has_test_signature(i: &ast::Item) -> HasTestSignature {
match &i.node {
&ast::ItemFn(ref decl, _, _, ref generics, _) => {
let no_output = match decl.output {
ast::Return(ref ret_ty) => match ret_ty.node {
ast::TyTup(ref tys) if tys.is_empty() => true,
_ => false,
},
ast::NoReturn(_) => false
};
if decl.inputs.is_empty()
&& no_output
&& !generics.is_parameterized() {
Yes
} else {
No
}
}
_ => NotEvenAFunction,
}
}
if has_test_attr {
let diag = cx.span_diagnostic;
match has_test_signature(i) {
Yes => {},
No => diag.span_err(i.span, "functions used as tests must have signature fn() -> ()"),
NotEvenAFunction => diag.span_err(i.span,
"only functions may be used as tests"),
}
}
return has_test_attr && has_test_signature(i) == Yes;
}
fn is_bench_fn(cx: &TestCtxt, i: &ast::Item) -> bool {
let has_bench_attr = attr::contains_name(i.attrs.as_slice(), "bench");
fn has_test_signature(i: &ast::Item) -> bool {
match i.node {
ast::ItemFn(ref decl, _, _, ref generics, _) => {
let input_cnt = decl.inputs.len();
let no_output = match decl.output {
ast::Return(ref ret_ty) => match ret_ty.node {
ast::TyTup(ref tys) if tys.is_empty() => true,
_ => false,
},
ast::NoReturn(_) => false
};
let tparm_cnt = generics.ty_params.len();
// NB: inadequate check, but we're running
// well before resolve, can't get too deep.
input_cnt == 1u
&& no_output && tparm_cnt == 0u
}
_ => false
}
}
if has_bench_attr && !has_test_signature(i) {
let diag = cx.span_diagnostic;
diag.span_err(i.span, "functions used as benches must have signature \
`fn(&mut Bencher) -> ()`");
}
return has_bench_attr && has_test_signature(i);
}
fn is_ignored(i: &ast::Item) -> bool {
i.attrs.iter().any(|attr| attr.check_name("ignore"))
}
fn should_fail(i: &ast::Item) -> ShouldFail {
match i.attrs.iter().find(|attr| attr.check_name("should_fail")) {
Some(attr) => {
let msg = attr.meta_item_list()
.and_then(|list| list.iter().find(|mi| mi.check_name("expected")))
.and_then(|mi| mi.value_str());
ShouldFail::Yes(msg)
}
None => ShouldFail::No,
}
}
/*
We're going to be building a module that looks more or less like:
mod __test {
extern crate test (name = "test", vers = "...");
fn main() {
test::test_main_static(::os::args().as_slice(), tests)
}
static tests : &'static [test::TestDescAndFn] = &[
... the list of tests in the crate ...
];
}
*/
fn mk_std(cx: &TestCtxt) -> ast::ViewItem {
let id_test = token::str_to_ident("test");
let (vi, vis) = if cx.is_test_crate {
(ast::ViewItemUse(
P(nospan(ast::ViewPathSimple(id_test,
path_node(vec!(id_test)),
ast::DUMMY_NODE_ID)))),
ast::Public)
} else {
(ast::ViewItemExternCrate(id_test, None, ast::DUMMY_NODE_ID),
ast::Inherited)
};
ast::ViewItem {
node: vi,
attrs: Vec::new(),
vis: vis,
span: DUMMY_SP
}
}
fn mk_test_module(cx: &mut TestCtxt) -> (P<ast::Item>, Option<ast::ViewItem>) {
// Link to test crate
let view_items = vec!(mk_std(cx));
// A constant vector of test descriptors.
let tests = mk_tests(cx);
// The synthesized main function which will call the console test runner
// with our list of tests
let mainfn = (quote_item!(&mut cx.ext_cx,
pub fn main() {
#![main]
use std::slice::AsSlice;
test::test_main_static(::std::os::args().as_slice(), TESTS);
}
)).unwrap();
let testmod = ast::Mod {
inner: DUMMY_SP,
view_items: view_items,
items: vec!(mainfn, tests),
};
let item_ = ast::ItemMod(testmod);
let mod_ident = token::gensym_ident("__test");
let item = ast::Item {
ident: mod_ident,
attrs: Vec::new(),
id: ast::DUMMY_NODE_ID,
node: item_,
vis: ast::Public,
span: DUMMY_SP,
};
let reexport = cx.reexport_test_harness_main.as_ref().map(|s| {
// building `use <ident> = __test::main`
let reexport_ident = token::str_to_ident(s.get());
let use_path =
nospan(ast::ViewPathSimple(reexport_ident,
path_node(vec![mod_ident, token::str_to_ident("main")]),
ast::DUMMY_NODE_ID));
ast::ViewItem {
node: ast::ViewItemUse(P(use_path)),
attrs: vec![],
vis: ast::Inherited,
span: DUMMY_SP
}
});
debug!("Synthetic test module:\n{}\n", pprust::item_to_string(&item));
(P(item), reexport)
}
fn nospan<T>(t: T) -> codemap::Spanned<T> {
codemap::Spanned { node: t, span: DUMMY_SP }
}
fn path_node(ids: Vec<ast::Ident> ) -> ast::Path {
ast::Path {
span: DUMMY_SP,
global: false,
segments: ids.into_iter().map(|identifier| ast::PathSegment {
identifier: identifier,
parameters: ast::PathParameters::none(),
}).collect()
}
}
fn mk_tests(cx: &TestCtxt) -> P<ast::Item> {
// The vector of test_descs for this crate
let test_descs = mk_test_descs(cx);
// FIXME #15962: should be using quote_item, but that stringifies
// __test_reexports, causing it to be reinterned, losing the
// gensym information.
let sp = DUMMY_SP;
let ecx = &cx.ext_cx;
let struct_type = ecx.ty_path(ecx.path(sp, vec![ecx.ident_of("self"),
ecx.ident_of("test"),
ecx.ident_of("TestDescAndFn")]));
let static_lt = ecx.lifetime(sp, token::special_idents::static_lifetime.name);
// &'static [self::test::TestDescAndFn]
let static_type = ecx.ty_rptr(sp,
ecx.ty(sp, ast::TyVec(struct_type)),
Some(static_lt),
ast::MutImmutable);
// static TESTS: $static_type = &[...];
ecx.item_const(sp,
ecx.ident_of("TESTS"),
static_type,
test_descs)
}
fn is_test_crate(krate: &ast::Crate) -> bool {
match attr::find_crate_name(krate.attrs.as_slice()) {
Some(ref s) if "test" == s.get().as_slice() => true,
_ => false
}
}
fn mk_test_descs(cx: &TestCtxt) -> P<ast::Expr> {
debug!("building test vector from {} tests", cx.testfns.len());
P(ast::Expr {
id: ast::DUMMY_NODE_ID,
node: ast::ExprAddrOf(ast::MutImmutable,
P(ast::Expr {
id: ast::DUMMY_NODE_ID,
node: ast::ExprVec(cx.testfns.iter().map(|test| {
mk_test_desc_and_fn_rec(cx, test)
}).collect()),
span: DUMMY_SP,
})),
span: DUMMY_SP,
})
}
fn mk_test_desc_and_fn_rec(cx: &TestCtxt, test: &Test) -> P<ast::Expr> {
// FIXME #15962: should be using quote_expr, but that stringifies
// __test_reexports, causing it to be reinterned, losing the
// gensym information.
let span = test.span;
let path = test.path.clone();
let ecx = &cx.ext_cx;
let self_id = ecx.ident_of("self");
let test_id = ecx.ident_of("test");
// creates self::test::$name
let test_path = |name| {
ecx.path(span, vec![self_id, test_id, ecx.ident_of(name)])
};
// creates $name: $expr
let field = |name, expr| ecx.field_imm(span, ecx.ident_of(name), expr);
debug!("encoding {}", ast_util::path_name_i(path.as_slice()));
// path to the #[test] function: "foo::bar::baz"
let path_string = ast_util::path_name_i(path.as_slice());
let name_expr = ecx.expr_str(span, token::intern_and_get_ident(path_string.as_slice()));
// self::test::StaticTestName($name_expr)
let name_expr = ecx.expr_call(span,
ecx.expr_path(test_path("StaticTestName")),
vec![name_expr]);
let ignore_expr = ecx.expr_bool(span, test.ignore);
let should_fail_path = |name| {
ecx.path(span, vec![self_id, test_id, ecx.ident_of("ShouldFail"), ecx.ident_of(name)])
};
let fail_expr = match test.should_fail {
ShouldFail::No => ecx.expr_path(should_fail_path("No")),
ShouldFail::Yes(ref msg) => {
let path = should_fail_path("Yes");
let arg = match *msg {
Some(ref msg) => ecx.expr_some(span, ecx.expr_str(span, msg.clone())),
None => ecx.expr_none(span),
};
ecx.expr_call(span, ecx.expr_path(path), vec![arg])
}
};
// self::test::TestDesc { ... }
let desc_expr = ecx.expr_struct(
span,
test_path("TestDesc"),
vec![field("name", name_expr),
field("ignore", ignore_expr),
field("should_fail", fail_expr)]);
let mut visible_path = match cx.toplevel_reexport {
Some(id) => vec![id],
None => {
let diag = cx.span_diagnostic;
diag.handler.bug("expected to find top-level re-export name, but found None");
}
};
visible_path.extend(path.into_iter());
let fn_expr = ecx.expr_path(ecx.path_global(span, visible_path));
let variant_name = if test.bench { "StaticBenchFn" } else { "StaticTestFn" };
// self::test::$variant_name($fn_expr)
let testfn_expr = ecx.expr_call(span, ecx.expr_path(test_path(variant_name)), vec![fn_expr]);
// self::test::TestDescAndFn { ... }
ecx.expr_struct(span,
test_path("TestDescAndFn"),
vec![field("desc", desc_expr),
field("testfn", testfn_expr)])
}