[lldb][test] XcodeSDKModuleTests: remove non-deterministic source mapping checks

[Michael137]

This assertion was added to check that RegisterXcodeSDK will correctly update the source mappings of the module. However, the source mapping will only get updated if the Host::RunShellCommand call to xcrun succeeded. Even if xcrun failed to find an SDK, the source mappings would get an entry. But if the shell invocation itself failed, then the mappings are not updated (see

llvm-project/lldb/source/Host/macosx/objcxx/HostInfoMacOSX.mm

Lines 424 to 444 in f6212c1

	lldb_private::Status error = Host::RunShellCommand(
	args, FileSpec(), &status, &signo, &output_str, timeout, run_in_shell);
	// Check that xcrun returned something useful.
	if (error.Fail()) {
	// Catastrophic error.
	LLDB_LOG(log, "xcrun failed to execute: {0}", error);
	return error.ToError();
	}
	if (status != 0) {
	// xcrun didn't find a matching SDK. Not an error, we'll try
	// different spellings.
	LLDB_LOG(log, "xcrun returned exit code {0}", status);
	if (!output_str.empty())
	LLDB_LOG(log, "xcrun output was:\n{0}", output_str);
	return "";
	}
	if (output_str.empty()) {
	LLDB_LOG(log, "xcrun returned no results");
	return "";
	}

). This means depending on how slow xcrun is on a given host, this test may fail. On my machine this happens consistently in debug and release builds.

This patch removes this flakey assertion. We unfortunately lost some test coverage here but I'm not sure there's great alternatives unless we either:

1. Mock the xcrun call somehow (we could maybe pass a callable around which defaults to xcrun in non-test code?)
2. Make a xcrun time-out not an error either?

[llvmbot]

@llvm/pr-subscribers-lldb

Author: Michael Buch (Michael137)

Changes

This assertion was added to check that RegisterXcodeSDK will correctly update the source mappings of the module. However, the source mapping will only get updated if the command-line invocation of xcrun succeeded. Even if xcrun failed to find an SDK, the source mappings would get an entry (see

llvm-project/lldb/source/Host/macosx/objcxx/HostInfoMacOSX.mm

Lines 424 to 444 in f6212c1

	lldb_private::Status error = Host::RunShellCommand(
	args, FileSpec(), &status, &signo, &output_str, timeout, run_in_shell);
	// Check that xcrun returned something useful.
	if (error.Fail()) {
	// Catastrophic error.
	LLDB_LOG(log, "xcrun failed to execute: {0}", error);
	return error.ToError();
	}
	if (status != 0) {
	// xcrun didn't find a matching SDK. Not an error, we'll try
	// different spellings.
	LLDB_LOG(log, "xcrun returned exit code {0}", status);
	if (!output_str.empty())
	LLDB_LOG(log, "xcrun output was:\n{0}", output_str);
	return "";
	}
	if (output_str.empty()) {
	LLDB_LOG(log, "xcrun returned no results");
	return "";
	}

). But if the shell invocation itself failed, then the mappings are not updated. This means depending on how slow xcrun is on a given host, this test may fail. On my machine this happens consistently in debug and release builds.

This patch removes this flakey assertion. We unfortunately lost some test coverage here but I'm not sure there's great alternatives unless we either:

1. Mock the xcrun call somehow (we could maybe pass a callable around which defaults to xcrun in non-test code?)
2. Make a xcrun time-out not an error either?

---

Full diff: https://github.com/llvm/llvm-project/pull/129526.diff

1 Files Affected:

• (modified) lldb/unittests/SymbolFile/DWARF/XcodeSDKModuleTests.cpp (-3)

diff --git a/lldb/unittests/SymbolFile/DWARF/XcodeSDKModuleTests.cpp b/lldb/unittests/SymbolFile/DWARF/XcodeSDKModuleTests.cpp
index fc008ca7011e4..b3bf4d9219d3e 100644
--- a/lldb/unittests/SymbolFile/DWARF/XcodeSDKModuleTests.cpp
+++ b/lldb/unittests/SymbolFile/DWARF/XcodeSDKModuleTests.cpp
@@ -116,11 +116,8 @@ TEST_F(XcodeSDKModuleTests, TestModuleGetXcodeSDK) {
   SymbolFileDWARF &sym_file = dwarf_cu->GetSymbolFileDWARF();
   CompUnitSP comp_unit = sym_file.GetCompileUnitAtIndex(0);
   ASSERT_TRUE(static_cast<bool>(comp_unit.get()));
-  ModuleSP module = t.GetModule();
-  ASSERT_EQ(module->GetSourceMappingList().GetSize(), 0u);
   XcodeSDK sdk = sym_file.ParseXcodeSDK(*comp_unit);
   ASSERT_EQ(sdk.GetType(), XcodeSDK::Type::MacOSX);
-  ASSERT_EQ(module->GetSourceMappingList().GetSize(), 1u);
 }
 
 TEST_F(XcodeSDKModuleTests, TestSDKPathFromDebugInfo_InvalidSDKPath) {