Skip to content


Subversion checkout URL

You can clone with
Download ZIP
Fetching contributors…

Cannot retrieve contributors at this time

508 lines (411 sloc) 15.947 kb
// Code that generates a test runner to run all the tests in a crate
use syntax::{ast, ast_util};
use syntax::ast_util::*;
//import syntax::ast_util::dummy_sp;
use syntax::fold;
use syntax::print::pprust;
use syntax::codemap::span;
use driver::session;
use session::session;
use syntax::attr;
use dvec::DVec;
export modify_for_testing;
type node_id_gen = fn@() -> ast::node_id;
type test = {span: span, path: ~[ast::ident],
ignore: bool, should_fail: bool};
type test_ctxt =
@{sess: session::session,
crate: @ast::crate,
mut path: ~[ast::ident],
testfns: DVec<test>};
// Traverse the crate, collecting all the test functions, eliding any
// existing main functions, and synthesizing a main test harness
fn modify_for_testing(sess: session::session,
crate: @ast::crate) -> @ast::crate {
if sess.opts.test {
generate_test_harness(sess, crate)
} else {
fn generate_test_harness(sess: session::session,
crate: @ast::crate) -> @ast::crate {
let cx: test_ctxt =
@{sess: sess,
crate: crate,
mut path: ~[],
testfns: DVec()};
let precursor =
@{fold_crate: fold::wrap(|a,b| fold_crate(cx, a, b) ),
fold_item: |a,b| fold_item(cx, a, b),
fold_mod: |a,b| fold_mod(cx, a, b),.. *fold::default_ast_fold()};
let fold = fold::make_fold(precursor);
let res = @fold.fold_crate(*crate);
return res;
fn strip_test_functions(crate: @ast::crate) -> @ast::crate {
// When not compiling with --test we should not compile the
// #[test] functions
do config::strip_items(crate) |attrs| {
!attr::contains_name(attr::attr_metas(attrs), ~"test")
fn fold_mod(cx: test_ctxt, m: ast::_mod, fld: fold::ast_fold) -> ast::_mod {
// Remove any defined main function from the AST so it doesn't clash with
// the one we're going to add.
// FIXME (#2403): This is sloppy. Instead we should have some mechanism to
// indicate to the translation pass which function we want to be main.
fn nomain(cx: test_ctxt, item: @ast::item) -> Option<@ast::item> {
match item.node {
ast::item_fn(*) => {
if item.ident == cx.sess.ident_of(~"main") {
} else { option::Some(item) }
_ => option::Some(item)
let mod_nomain =
{view_items: m.view_items,
items: vec::filter_map(m.items, |i| nomain(cx, *i))};
return fold::noop_fold_mod(mod_nomain, fld);
fn fold_crate(cx: test_ctxt, c: ast::crate_, fld: fold::ast_fold) ->
ast::crate_ {
let folded = fold::noop_fold_crate(c, fld);
// Add a special __test module to the crate that will contain code
// generated for the test harness
return {module: add_test_module(cx, folded.module),.. folded};
fn fold_item(cx: test_ctxt, &&i: @ast::item, fld: fold::ast_fold) ->
Option<@ast::item> {
debug!("current path: %s",
ast_util::path_name_i(cx.path, cx.sess.parse_sess.interner));
if is_test_fn(i) {
match i.node {
ast::item_fn(_, purity, _, _) if purity == ast::unsafe_fn => {
~"unsafe functions cannot be used for tests");
_ => {
debug!("this is a test function");
let test = {span: i.span,
path: cx.path, ignore: is_ignored(cx, i),
should_fail: should_fail(i)};
debug!("have %u test functions", cx.testfns.len());
let res = fold::noop_fold_item(i, fld);
return res;
fn is_test_fn(i: @ast::item) -> bool {
let has_test_attr =
vec::len(attr::find_attrs_by_name(i.attrs, ~"test")) > 0u;
fn has_test_signature(i: @ast::item) -> bool {
match i.node {
ast::item_fn(decl, _, tps, _) => {
let input_cnt = vec::len(decl.inputs);
let no_output = match decl.output.node {
ast::ty_nil => true,
_ => false
let tparm_cnt = vec::len(tps);
input_cnt == 0u && no_output && tparm_cnt == 0u
_ => false
return has_test_attr && has_test_signature(i);
fn is_ignored(cx: test_ctxt, i: @ast::item) -> bool {
let ignoreattrs = attr::find_attrs_by_name(i.attrs, ~"ignore");
let ignoreitems = attr::attr_metas(ignoreattrs);
let cfg_metas = vec::concat(vec::filter_map(ignoreitems,
|i| attr::get_meta_item_list(*i)));
return if vec::is_not_empty(ignoreitems) {
config::metas_in_cfg(cx.crate.node.config, cfg_metas)
} else {
fn should_fail(i: @ast::item) -> bool {
vec::len(attr::find_attrs_by_name(i.attrs, ~"should_fail")) > 0u
fn add_test_module(cx: test_ctxt, m: ast::_mod) -> ast::_mod {
let testmod = mk_test_module(cx);
return {items: vec::append_one(m.items, testmod),.. m};
We're going to be building a module that looks more or less like:
mod __test {
fn main(args: ~[str]) -> int {
std::test::test_main(args, tests())
fn tests() -> ~[std::test::test_desc] {
... the list of tests in the crate ...
fn mk_test_module(cx: test_ctxt) -> @ast::item {
// A function that generates a vector of test descriptors to feed to the
// test runner
let testsfn = mk_tests(cx);
// The synthesized main function which will call the console test runner
// with our list of tests
let mainfn = mk_main(cx);
let testmod: ast::_mod = {view_items: ~[], items: ~[mainfn, testsfn]};
let item_ = ast::item_mod(testmod);
// This attribute tells resolve to let us call unexported functions
let resolve_unexported_attr =
let item: ast::item =
{ident: cx.sess.ident_of(~"__test"),
attrs: ~[resolve_unexported_attr],
id: cx.sess.next_node_id(),
node: item_,
vis: ast::public,
span: dummy_sp()};
debug!("Synthetic test module:\n%s\n",
pprust::item_to_str(@item, cx.sess.intr()));
return @item;
fn nospan<T: Copy>(t: T) -> ast::spanned<T> {
return {node: t, span: dummy_sp()};
fn path_node(ids: ~[ast::ident]) -> @ast::path {
@{span: dummy_sp(), global: false, idents: ids, rp: None, types: ~[]}
fn mk_tests(cx: test_ctxt) -> @ast::item {
let ret_ty = mk_test_desc_vec_ty(cx);
let decl: ast::fn_decl =
{inputs: ~[],
output: ret_ty,
cf: ast::return_val};
// The vector of test_descs for this crate
let test_descs = mk_test_desc_vec(cx);
let body_: ast::blk_ =
default_block(~[], option::Some(test_descs), cx.sess.next_node_id());
let body = nospan(body_);
let item_ = ast::item_fn(decl, ast::impure_fn, ~[], body);
let item: ast::item =
{ident: cx.sess.ident_of(~"tests"),
attrs: ~[],
id: cx.sess.next_node_id(),
node: item_,
vis: ast::public,
span: dummy_sp()};
return @item;
fn mk_path(cx: test_ctxt, path: ~[ast::ident]) -> ~[ast::ident] {
// For tests that are inside of std we don't want to prefix
// the paths with std::
let is_std = {
let items = attr::find_linkage_metas(cx.crate.node.attrs);
match attr::last_meta_item_value_str_by_name(items, ~"name") {
Some(~"std") => true,
_ => false
if is_std { path }
else { vec::append(~[cx.sess.ident_of(~"std")], path) }
// The ast::ty of ~[std::test::test_desc]
fn mk_test_desc_vec_ty(cx: test_ctxt) -> @ast::ty {
let test_desc_ty_path =
path_node(mk_path(cx, ~[cx.sess.ident_of(~"test"),
let test_desc_ty: ast::ty =
{id: cx.sess.next_node_id(),
node: ast::ty_path(test_desc_ty_path, cx.sess.next_node_id()),
span: dummy_sp()};
let vec_mt: ast::mt = {ty: @test_desc_ty, mutbl: ast::m_imm};
let inner_ty = @{id: cx.sess.next_node_id(),
node: ast::ty_vec(vec_mt),
span: dummy_sp()};
return @{id: cx.sess.next_node_id(),
node: ast::ty_uniq({ty: inner_ty, mutbl: ast::m_imm}),
span: dummy_sp()};
fn mk_test_desc_vec(cx: test_ctxt) -> @ast::expr {
debug!("building test vector from %u tests", cx.testfns.len());
let mut descs = ~[];
for cx.testfns.each |test| {
descs.push(mk_test_desc_rec(cx, *test));
let inner_expr = @{id: cx.sess.next_node_id(),
callee_id: cx.sess.next_node_id(),
node: ast::expr_vec(descs, ast::m_imm),
span: dummy_sp()};
return @{id: cx.sess.next_node_id(),
callee_id: cx.sess.next_node_id(),
node: ast::expr_vstore(inner_expr, ast::expr_vstore_uniq),
span: dummy_sp()};
fn mk_test_desc_rec(cx: test_ctxt, test: test) -> @ast::expr {
let span = test.span;
let path = test.path;
debug!("encoding %s", ast_util::path_name_i(path,
let name_lit: ast::lit =
nospan(ast::lit_str(@ast_util::path_name_i(path, cx.sess.parse_sess
let name_expr_inner: @ast::expr =
@{id: cx.sess.next_node_id(),
callee_id: cx.sess.next_node_id(),
node: ast::expr_lit(@name_lit),
span: span};
let name_expr = {id: cx.sess.next_node_id(),
callee_id: cx.sess.next_node_id(),
node: ast::expr_vstore(name_expr_inner,
span: dummy_sp()};
let name_field: ast::field =
nospan({mutbl: ast::m_imm, ident: cx.sess.ident_of(~"name"),
expr: @name_expr});
let fn_path = path_node(path);
let fn_expr: ast::expr =
{id: cx.sess.next_node_id(),
callee_id: cx.sess.next_node_id(),
node: ast::expr_path(fn_path),
span: span};
let fn_wrapper_expr = mk_test_wrapper(cx, fn_expr, span);
let fn_field: ast::field =
nospan({mutbl: ast::m_imm, ident: cx.sess.ident_of(~"testfn"),
expr: fn_wrapper_expr});
let ignore_lit: ast::lit = nospan(ast::lit_bool(test.ignore));
let ignore_expr: ast::expr =
{id: cx.sess.next_node_id(),
callee_id: cx.sess.next_node_id(),
node: ast::expr_lit(@ignore_lit),
span: span};
let ignore_field: ast::field =
nospan({mutbl: ast::m_imm, ident: cx.sess.ident_of(~"ignore"),
expr: @ignore_expr});
let fail_lit: ast::lit = nospan(ast::lit_bool(test.should_fail));
let fail_expr: ast::expr =
{id: cx.sess.next_node_id(),
callee_id: cx.sess.next_node_id(),
node: ast::expr_lit(@fail_lit),
span: span};
let fail_field: ast::field =
nospan({mutbl: ast::m_imm,
ident: cx.sess.ident_of(~"should_fail"),
expr: @fail_expr});
let desc_rec_: ast::expr_ =
ast::expr_rec(~[name_field, fn_field, ignore_field, fail_field],
let desc_rec: ast::expr =
{id: cx.sess.next_node_id(), callee_id: cx.sess.next_node_id(),
node: desc_rec_, span: span};
return @desc_rec;
// Produces a bare function that wraps the test function
// FIXME (#1281): This can go away once fn is the type of bare function.
fn mk_test_wrapper(cx: test_ctxt,
fn_path_expr: ast::expr,
span: span) -> @ast::expr {
let call_expr: ast::expr = {
id: cx.sess.next_node_id(),
callee_id: cx.sess.next_node_id(),
node: ast::expr_call(@fn_path_expr, ~[], false),
span: span
let call_stmt: ast::stmt = nospan(
ast::stmt_semi(@call_expr, cx.sess.next_node_id()));
let wrapper_decl: ast::fn_decl = {
inputs: ~[],
output: @{id: cx.sess.next_node_id(), node: ast::ty_nil, span: span},
cf: ast::return_val
let wrapper_body: ast::blk = nospan({
view_items: ~[],
stmts: ~[@call_stmt],
expr: option::None,
id: cx.sess.next_node_id(),
rules: ast::default_blk
let wrapper_expr: ast::expr = {
id: cx.sess.next_node_id(),
callee_id: cx.sess.next_node_id(),
node: ast::expr_fn(ast::proto_bare, wrapper_decl,
wrapper_body, @~[]),
span: span
return @wrapper_expr;
fn mk_main(cx: test_ctxt) -> @ast::item {
let ret_ty = {id: cx.sess.next_node_id(),
node: ast::ty_nil,
span: dummy_sp()};
let decl: ast::fn_decl =
{inputs: ~[],
output: @ret_ty,
cf: ast::return_val};
let test_main_call_expr = mk_test_main_call(cx);
let body_: ast::blk_ =
default_block(~[], option::Some(test_main_call_expr),
let body = {node: body_, span: dummy_sp()};
let item_ = ast::item_fn(decl, ast::impure_fn, ~[], body);
let item: ast::item =
{ident: cx.sess.ident_of(~"main"),
attrs: ~[],
id: cx.sess.next_node_id(),
node: item_,
vis: ast::public,
span: dummy_sp()};
return @item;
fn mk_test_main_call(cx: test_ctxt) -> @ast::expr {
// Call os::args to generate the vector of test_descs
let args_path = path_node(~[
let args_path_expr_: ast::expr_ = ast::expr_path(args_path);
let args_path_expr: ast::expr =
{id: cx.sess.next_node_id(), callee_id: cx.sess.next_node_id(),
node: args_path_expr_, span: dummy_sp()};
let args_call_expr_ = ast::expr_call(@args_path_expr, ~[], false);
let args_call_expr: ast::expr =
{id: cx.sess.next_node_id(), callee_id: cx.sess.next_node_id(),
node: args_call_expr_, span: dummy_sp()};
// Call __test::test to generate the vector of test_descs
let test_path = path_node(~[cx.sess.ident_of(~"tests")]);
let test_path_expr_: ast::expr_ = ast::expr_path(test_path);
let test_path_expr: ast::expr =
{id: cx.sess.next_node_id(), callee_id: cx.sess.next_node_id(),
node: test_path_expr_, span: dummy_sp()};
let test_call_expr_ = ast::expr_call(@test_path_expr, ~[], false);
let test_call_expr: ast::expr =
{id: cx.sess.next_node_id(), callee_id: cx.sess.next_node_id(),
node: test_call_expr_, span: dummy_sp()};
// Call std::test::test_main
let test_main_path = path_node(
mk_path(cx, ~[cx.sess.ident_of(~"test"),
let test_main_path_expr_: ast::expr_ = ast::expr_path(test_main_path);
let test_main_path_expr: ast::expr =
{id: cx.sess.next_node_id(), callee_id: cx.sess.next_node_id(),
node: test_main_path_expr_, span: dummy_sp()};
let test_main_call_expr_: ast::expr_ =
~[@args_call_expr, @test_call_expr], false);
let test_main_call_expr: ast::expr =
{id: cx.sess.next_node_id(), callee_id: cx.sess.next_node_id(),
node: test_main_call_expr_, span: dummy_sp()};
return @test_main_call_expr;
// Local Variables:
// mode: rust
// fill-column: 78;
// indent-tabs-mode: nil
// c-basic-offset: 4
// buffer-file-coding-system: utf-8-unix
// End:
Jump to Line
Something went wrong with that request. Please try again.