Change Target::FindBreakpointsByName to return Expected<vector>

Summary:
Using a BreakpointList corrupts the breakpoints' IDs because
BreakpointList::Add sets the ID, so use a vector instead, and
update the signature to return the vector wrapped in an
llvm::Expected which can propagate any error from the inner
call to StringIsBreakpointName.

Note that, despite the similar name, SBTarget::FindBreakpointsByName
doesn't suffer the same problem, because it uses a SBBreakpointList,
which is more like a BreakpointIDList than a BreakpointList under the
covers.

Add a check to TestBreakpointNames that, without this fix, notices the
ID getting mutated and fails.

Reviewers: jingham, JDevlieghere

Reviewed By: JDevlieghere

Subscribers: lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D70907

1 files changed, 8 insertions, 5 deletions

diff --git a/lldb/source/API/SBTarget.cpp b/lldb/source/API/SBTarget.cpp
index 7013e2b45e5..312e4df7586 100644
--- a/lldb/source/API/SBTarget.cpp
+++ b/lldb/source/API/SBTarget.cpp
@@ -1176,12 +1176,15 @@ bool SBTarget::FindBreakpointsByName(const char *name,
   TargetSP target_sp(GetSP());
   if (target_sp) {
     std::lock_guard<std::recursive_mutex> guard(target_sp->GetAPIMutex());
-    BreakpointList bkpt_list(false);
-    bool is_valid =
-        target_sp->GetBreakpointList().FindBreakpointsByName(name, bkpt_list);
-    if (!is_valid)
+    llvm::Expected<std::vector<BreakpointSP>> expected_vector =
+        target_sp->GetBreakpointList().FindBreakpointsByName(name);
+    if (!expected_vector) {
+      LLDB_LOG(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_BREAKPOINTS),
+               "invalid breakpoint name: {}",
+               llvm::toString(expected_vector.takeError()));
       return false;
-    for (BreakpointSP bkpt_sp : bkpt_list.Breakpoints()) {
+    }
+    for (BreakpointSP bkpt_sp : *expected_vector) {
       bkpts.AppendByID(bkpt_sp->GetID());
     }
   }