[lldb/test] Do a better job at setting (DY)LD_LIBRARY_PATH

Summary:
registerSharedLibrariesWithTarget was setting the library path
environment variable to the process build directory, but the function is
also accepting libraries in other directories (in which case they won't
be found automatically).

This patch makes the function set the path variable correctly for these
libraries too. This enables us to remove the code for setting the path
variable in TestWeakSymbols.py, which was working only accidentally --
it was relying on the fact that
  launch_info.SetEnvironmentEntries(..., append=True)
would not overwrite the path variable it has set, but that is going to
change with D83306.

Reviewers: davide, jingham

Subscribers: lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D83552

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

@@ -1881,8 +1881,7 @@ class TestBase(Base):
         shlib_prefix = self.platformContext.shlib_prefix
         shlib_extension = '.' + self.platformContext.shlib_extension
 
-        working_dir = self.get_process_working_directory()
-        environment = ['%s=%s' % (shlib_environment_var, working_dir)]
+        dirs = []
         # Add any shared libraries to our target if remote so they get
         # uploaded into the working directory on the remote side
         for name in shlibs:
@@ -1905,6 +1904,7 @@ class TestBase(Base):
                 # Make sure we found the local shared library in the above code
                 self.assertTrue(os.path.exists(local_shlib_path))
 
+
             # Add the shared library to our target
             shlib_module = target.AddModule(local_shlib_path, None, None, None)
             if lldb.remote_platform:
@@ -1914,8 +1914,15 @@ class TestBase(Base):
                     os.path.basename(local_shlib_path))
                 shlib_module.SetRemoteInstallFileSpec(
                     lldb.SBFileSpec(remote_shlib_path, False))
+                dir_to_add = self.get_process_working_directory()
+            else:
+                dir_to_add = os.path.dirname(local_shlib_path)
 
-        return environment
+            if dir_to_add not in dirs:
+                dirs.append(dir_to_add)
+
+        env_value = self.platformContext.shlib_path_separator.join(dirs)
+        return ['%s=%s' % (shlib_environment_var, env_value)]
 
     def registerSanitizerLibrariesWithTarget(self, target):
         runtimes = []

lldb/test/API/commands/expression/weak_symbols/TestWeakSymbols.py

@@ -48,10 +48,6 @@ class TestWeakSymbolsInExpressions(TestBase):
 
         launch_info = lldb.SBLaunchInfo(None)
         launch_info.SetWorkingDirectory(self.getBuildDir())
-        # We have to point to the hidden directory to pick up the
-        # version of the dylib without the weak symbols:
-        env_expr = self.platformContext.shlib_environment_var + "=" + hidden_dir
-        launch_info.SetEnvironmentEntries([env_expr], True)
 
         (self.target, _, thread, _) = lldbutil.run_to_source_breakpoint(
                                               self, "Set a breakpoint here",