[coroutines] Do not attempt to typo-correct when coroutine is looking for required members

[GorNishanov]

Summary

When SemaCoroutine looks for await_resume, it means it. No need for helpful: "Did you mean await_ready?" messages.

Fixes PR33477 and a couple of FIXMEs in test/SemaCXX/coroutines.cpp

[GorNishanov]

ping

[GorNishanov]

@rsmith , here is a fix for the funny diagnostics you mentioned.

[modocache]

Excellent, thanks!

[GorNishanov]

Fixed:
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@328663 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Sema/SemaCoroutine.cpp

static ExprResult buildMemberCall(Sema &S, Expr *Base, SourceLocation Loc,
   CXXScopeSpec SS;
   ExprResult Result = S.BuildMemberReferenceExpr(
       Base, Base->getType(), Loc, /*IsPtr=*/false, SS,
       SourceLocation(), nullptr, NameInfo, /*TemplateArgs=*/nullptr,
       /*Scope=*/nullptr);
   if (Result.isInvalid())
     return ExprError();
 
+  // We meant exactly what we asked for. No need for typo correction.
+  if (auto *TE = dyn_cast<TypoExpr>(Result.get())) {
+    S.clearDelayedTypo(TE);
+    S.Diag(Loc, diag::err_no_member)
+        << NameInfo.getName() << Base->getType()->getAsCXXRecordDecl()
+        << Base->getSourceRange();
+    return ExprError();
+  }
+
   return S.ActOnCallExpr(nullptr, Result.get(), Loc, Args, Loc, nullptr);
 }
 
 /// Build calls to await_ready, await_suspend, and await_resume for a co_await
 /// expression.
 static ReadySuspendResumeResult buildCoawaitCalls(Sema &S, VarDecl *CoroPromise,
                                                   SourceLocation Loc, Expr *E) {
   OpaqueValueExpr *Operand = new (S.Context)

test/SemaCXX/coroutines.cpp

struct bad_promise_1 {
   void return_void();
 };
 coro<bad_promise_1> missing_get_return_object() { // expected-error {{no member named 'get_return_object' in 'bad_promise_1'}}
   co_await a;
 }
 
 struct bad_promise_2 {
   coro<bad_promise_2> get_return_object();
-  // FIXME: We shouldn't offer a typo-correction here!
-  suspend_always final_suspend(); // expected-note {{here}}
+  suspend_always final_suspend();
   void unhandled_exception();
   void return_void();
 };
 // FIXME: This shouldn't happen twice
 coro<bad_promise_2> missing_initial_suspend() { // expected-error {{no member named 'initial_suspend' in 'bad_promise_2'}}
   co_await a;
 }
 
 struct bad_promise_3 {
   coro<bad_promise_3> get_return_object();
-  // FIXME: We shouldn't offer a typo-correction here!
-  suspend_always initial_suspend(); // expected-note {{here}}
+  suspend_always initial_suspend();
   void unhandled_exception();
   void return_void();
 };
 coro<bad_promise_3> missing_final_suspend() { // expected-error {{no member named 'final_suspend' in 'bad_promise_3'}}
   co_await a;
 }
 
 struct bad_promise_4 {

 };
 
 template struct DepTestType<int>; // expected-note {{requested here}}
 template CoroMemberTag DepTestType<int>::test_member_template(long, const char *) const &&;
 
 template CoroMemberTag DepTestType<int>::test_static_template<void>(const char *volatile &, unsigned);
 
 } // namespace CoroHandleMemberFunctionTest
+
+struct missing_await_ready {
+  void await_suspend(std::experimental::coroutine_handle<>);
+  void await_resume();
+};
+struct missing_await_suspend {
+  bool await_ready();
+  void await_resume();
+};
+struct missing_await_resume {
+  bool await_ready();
+  void await_suspend(std::experimental::coroutine_handle<>);
+};
+
+void test_missing_awaitable_members() {
+  co_await missing_await_ready{}; // expected-error {{no member named 'await_ready' in 'missing_await_ready'}}
+  co_await missing_await_suspend{}; // expected-error {{no member named 'await_suspend' in 'missing_await_suspend'}}
+  co_await missing_await_resume{}; // expected-error {{no member named 'await_resume' in 'missing_await_resume'}}
+}