Move test harness generation into libsyntax_ext

Author: petrochenkov

src/librustc_interface/passes.rs

@@ -453,7 +453,7 @@ fn configure_and_expand_inner<'a>(
     sess.profiler(|p| p.end_activity("macro expansion"));
 
     time(sess, "maybe building test harness", || {
-        syntax::test::modify_for_testing(
+        syntax_ext::test_harness::modify_for_testing(
             &sess.parse_sess,
             &mut resolver,
             sess.opts.test,

src/libsyntax/lib.rs

@@ -156,7 +156,6 @@ pub mod show_span;
 pub mod std_inject;
 pub use syntax_pos::edition;
 pub use syntax_pos::symbol;
-pub mod test;
 pub mod tokenstream;
 pub mod visit;
 

src/libsyntax_ext/Cargo.toml

@@ -10,11 +10,11 @@ path = "lib.rs"
 doctest = false
 
 [dependencies]
-fmt_macros = { path = "../libfmt_macros" }
 errors = { path = "../librustc_errors", package = "rustc_errors" }
-syntax = { path = "../libsyntax" }
-syntax_pos = { path = "../libsyntax_pos" }
+fmt_macros = { path = "../libfmt_macros" }
+log = "0.4"
 rustc_data_structures = { path = "../librustc_data_structures" }
 rustc_target = { path = "../librustc_target" }
 smallvec = { version = "0.6.7", features = ["union", "may_dangle"] }
-log = "0.4"
+syntax = { path = "../libsyntax" }
+syntax_pos = { path = "../libsyntax_pos" }

src/libsyntax_ext/lib.rs

@@ -6,6 +6,7 @@
 #![deny(unused_lifetimes)]
 
 #![feature(decl_macro)]
+#![feature(mem_take)]
 #![feature(nll)]
 #![feature(rustc_diagnostic_macros)]
 #![feature(unicode_internals)]
@@ -29,10 +30,10 @@ mod global_asm;
 mod log_syntax;
 mod source_util;
 mod test;
-mod test_case;
 mod trace_macros;
 
 pub mod proc_macro_decls;
+pub mod test_harness;
 
 use rustc_data_structures::sync::Lrc;
 use syntax::ast;
@@ -130,7 +131,7 @@ pub fn register_builtins(resolver: &mut dyn syntax::ext::base::Resolver,
         )),
         allow_internal_unstable: allow_internal_unstable.clone(),
         ..SyntaxExtension::default(
-            SyntaxExtensionKind::LegacyAttr(Box::new(test_case::expand)), edition
+            SyntaxExtensionKind::LegacyAttr(Box::new(test::expand_test_case)), edition
         )
     });
     register(sym::test, SyntaxExtension {

src/libsyntax_ext/test.rs

@@ -7,11 +7,44 @@ use syntax::ext::base::*;
 use syntax::ext::build::AstBuilder;
 use syntax::ext::hygiene::SyntaxContext;
 use syntax::print::pprust;
+use syntax::source_map::respan;
 use syntax::symbol::{Symbol, sym};
 use syntax_pos::Span;
 
 use std::iter;
 
+// #[test_case] is used by custom test authors to mark tests
+// When building for test, it needs to make the item public and gensym the name
+// Otherwise, we'll omit the item. This behavior means that any item annotated
+// with #[test_case] is never addressable.
+//
+// We mark item with an inert attribute "rustc_test_marker" which the test generation
+// logic will pick up on.
+pub fn expand_test_case(
+    ecx: &mut ExtCtxt<'_>,
+    attr_sp: Span,
+    meta_item: &ast::MetaItem,
+    anno_item: Annotatable
+) -> Vec<Annotatable> {
+    check_builtin_macro_attribute(ecx, meta_item, sym::test_case);
+
+    if !ecx.ecfg.should_test { return vec![]; }
+
+    let sp = attr_sp.with_ctxt(SyntaxContext::empty().apply_mark(ecx.current_expansion.mark));
+    let mut item = anno_item.expect_item();
+    item = item.map(|mut item| {
+        item.vis = respan(item.vis.span, ast::VisibilityKind::Public);
+        item.ident = item.ident.gensym();
+        item.attrs.push(
+            ecx.attribute(sp,
+                ecx.meta_word(sp, sym::rustc_test_marker))
+        );
+        item
+    });
+
+    return vec![Annotatable::Item(item)]
+}
+
 pub fn expand_test(
     cx: &mut ExtCtxt<'_>,
     attr_sp: Span,

src/libsyntax_ext/test_case.rs

@@ -1,35 +1,23 @@
 // Code that generates a test runner to run all the tests in a crate
 
-#![allow(dead_code)]
-#![allow(unused_imports)]
-
-use HasTestSignature::*;
-
-use std::iter;
-use std::slice;
-use std::mem;
-use std::vec;
-
 use log::debug;
 use smallvec::{smallvec, SmallVec};
-use syntax_pos::{DUMMY_SP, NO_EXPANSION, Span, SourceFile, BytePos};
-
-use crate::attr::{self, HasAttrs};
-use crate::source_map::{self, SourceMap, ExpnInfo, ExpnKind, dummy_spanned, respan};
-use crate::config;
-use crate::entry::{self, EntryPointType};
-use crate::ext::base::{ExtCtxt, Resolver};
-use crate::ext::build::AstBuilder;
-use crate::ext::expand::ExpansionConfig;
-use crate::ext::hygiene::{self, ExpnId, SyntaxContext, MacroKind};
-use crate::mut_visit::{*, ExpectOne};
-use crate::feature_gate::Features;
-use crate::util::map_in_place::MapInPlace;
-use crate::parse::{token, ParseSess};
-use crate::ast::{self, Ident};
-use crate::ptr::P;
-use crate::symbol::{self, Symbol, kw, sym};
-use crate::ThinVec;
+use syntax::ast::{self, Ident};
+use syntax::attr;
+use syntax::entry::{self, EntryPointType};
+use syntax::ext::base::{ExtCtxt, Resolver};
+use syntax::ext::build::AstBuilder;
+use syntax::ext::expand::ExpansionConfig;
+use syntax::ext::hygiene::{ExpnId, MacroKind};
+use syntax::feature_gate::Features;
+use syntax::mut_visit::{*, ExpectOne};
+use syntax::parse::ParseSess;
+use syntax::ptr::P;
+use syntax::source_map::{ExpnInfo, ExpnKind, dummy_spanned};
+use syntax::symbol::{kw, sym, Symbol};
+use syntax_pos::{Span, DUMMY_SP};
+
+use std::{iter, mem};
 
 struct Test {
     span: Span,
@@ -42,10 +30,7 @@ struct TestCtxt<'a> {
     ext_cx: ExtCtxt<'a>,
     test_cases: Vec<Test>,
     reexport_test_harness_main: Option<Symbol>,
-    is_libtest: bool,
-    features: &'a Features,
     test_runner: Option<ast::Path>,
-
     // top-level re-export submodule, filled out after folding is finished
     toplevel_reexport: Option<Ident>,
 }
@@ -267,11 +252,7 @@ fn generate_test_harness(sess: &ParseSess,
         path: Vec::new(),
         test_cases: Vec::new(),
         reexport_test_harness_main,
-        // N.B., doesn't consider the value of `--crate-name` passed on the command line.
-        is_libtest: attr::find_crate_name(&krate.attrs)
-            .map(|s| s == sym::test).unwrap_or(false),
         toplevel_reexport: None,
-        features,
         test_runner
     };
 
@@ -282,19 +263,6 @@ fn generate_test_harness(sess: &ParseSess,
     }.visit_crate(krate);
 }
 
-enum HasTestSignature {
-    Yes,
-    No(BadTestSignature),
-}
-
-#[derive(PartialEq)]
-enum BadTestSignature {
-    NotEvenAFunction,
-    WrongTypeSignature,
-    NoArgumentsAllowed,
-    ShouldPanicOnlyWithNoArgs,
-}
-
 /// Creates a function item for use as the main function of a test build.
 /// This function will call the `test_runner` as specified by the crate attribute
 fn mk_main(cx: &mut TestCtxt<'_>) -> P<ast::Item> {