[lldb/Test] Assert that no targets or modules remain after a test completes.

The reproducer intentionally leak every object allocated during replay,
which means that modules never get orphaned. If this were to happen for
another reason, we might not be testing what we think we are. Assert
that there are no targets left at the end of a test and that the global
module cache is empty in the non-reproducer scenario.

Differential revision: https://reviews.llvm.org/D81612

lldb/bindings/interface/SBModule.i

@@ -344,6 +344,15 @@ public:
     lldb::SBAddress
     GetObjectFileEntryPointAddress() const;
 
+    %feature("docstring", "
+    Returns the number of modules in the module cache. This is an
+    implementation detail exposed for testing and should not be relied upon.
+
+    @return
+        The number of modules in the module cache.") GetNumberAllocatedModules;
+    static uint32_t
+    GetNumberAllocatedModules();
+
     STRING_EXTENSION(SBModule)
 
 #ifdef SWIGPYTHON

lldb/include/lldb/API/SBModule.h

@@ -288,6 +288,9 @@ public:
   lldb::SBAddress GetObjectFileHeaderAddress() const;
   lldb::SBAddress GetObjectFileEntryPointAddress() const;
 
+  /// Get the number of global modules.
+  static uint32_t GetNumberAllocatedModules();
+
 private:
   friend class SBAddress;
   friend class SBFrame;

lldb/packages/Python/lldbsuite/test/lldbtest.py

@@ -2018,10 +2018,18 @@ class TestBase(Base):
                 process = target.GetProcess()
                 if process:
                     rc = self.invoke(process, "Kill")
-                    self.assertTrue(rc.Success(), PROCESS_KILLED)
+                    assert rc.Success()
         for target in targets:
             self.dbg.DeleteTarget(target)
 
+        # Modules are not orphaned during reproducer replay because they're
+        # leaked on purpose.
+        if not configuration.is_reproducer():
+            # Assert that all targets are deleted.
+            assert self.dbg.GetNumTargets() == 0
+            # Assert that the global module cache is empty.
+            assert lldb.SBModule.GetNumberAllocatedModules() == 0
+
         # Do this last, to make sure it's in reverse order from how we setup.
         Base.tearDown(self)
 

lldb/source/API/SBModule.cpp

@@ -683,6 +683,13 @@ lldb::SBAddress SBModule::GetObjectFileEntryPointAddress() const {
   return LLDB_RECORD_RESULT(sb_addr);
 }
 
+uint32_t SBModule::GetNumberAllocatedModules() {
+  LLDB_RECORD_STATIC_METHOD_NO_ARGS(uint32_t, SBModule,
+                                    GetNumberAllocatedModules);
+
+  return Module::GetNumberAllocatedModules();
+}
+
 namespace lldb_private {
 namespace repro {
 
@@ -757,6 +764,8 @@ void RegisterMethods<SBModule>(Registry &R) {
                              GetObjectFileHeaderAddress, ());
   LLDB_REGISTER_METHOD_CONST(lldb::SBAddress, SBModule,
                              GetObjectFileEntryPointAddress, ());
+  LLDB_REGISTER_STATIC_METHOD(uint32_t, SBModule, GetNumberAllocatedModules,
+                              ());
 }
 
 }