Add environment var LLDBVSCODE_SKIP_INIT_FILES to lldb-vscode

[wallace]

Summary

lldb has the -x option but this doesn't exist at all for lldb-vscode. To be honest my main goal is the ability to run the lldb-vscode tests without an lldbinit file polluting it.
The DAP doesn't seem to have it (https://microsoft.github.io/debug-adapter-protocol/specification#Requests_Initialize) so we're adding it as an env var.

[aadsm]

Oops, wrnog default

[clayborg]

If MS VS Code IDE itself will never pass this to the "initialize" packet, then we might just want to use an env var instead? You should probably get rid of https://reviews.llvm.org/D70886 and just modify this patch?

[aadsm]

Yes, I'll change this to env it makes more sense.

[aadsm]

Use an env var instead

[clayborg]

lldb/tools/lldb-vscode/lldb-vscode.cpp

64

make singleton function:

bool GetSkipInitFiles() {
  static const bool skip_init = getenv("LLDBVSCODE_SKIP_INIT_FILES") != NULL;
  return skip_init;
}

[aadsm]

Put the logic into a function

[wallace]

not needed anymore because of D99974

lldb/packages/Python/lldbsuite/test/tools/lldb-vscode/vscode.py

def request_initialize(self):
                 'adapterID': 'lldb-native',
                 'clientID': 'vscode',
                 'columnsStartAt1': True,
                 'linesStartAt1': True,
                 'locale': 'en-us',
                 'pathFormat': 'path',
                 'supportsRunInTerminalRequest': True,
                 'supportsVariablePaging': True,
-                'supportsVariableType': True
+                'supportsVariableType': True,
+                'skipInitFiles': True,
             }
         }
         response = self.send_recv(command_dict)
         if response:
             if 'body' in response:
                 self.initialize_body = response['body']
         return response
 

lldb/tools/lldb-vscode/lldb-vscode.cpp

 typedef int socklen_t;
 constexpr const char *dev_null_path = "nul";
 
 #else
 constexpr const char *dev_null_path = "/dev/null";
 
 #endif
 
 using namespace lldb_vscode;
 
 namespace {
 
 typedef void (*RequestCallback)(const llvm::json::Object &command);
 
 enum LaunchMethod { Launch, Attach, AttachForSuspendedLaunch };
 
 enum VSCodeBroadcasterBits { eBroadcastBitStopEventThread = 1u << 0 };

 //       "body": {
 //         "$ref": "#/definitions/Capabilities",
 //         "description": "The capabilities of this debug adapter."
 //       }
 //     }
 //   }]
 // }
 void request_initialize(const llvm::json::Object &request) {
-  g_vsc.debugger = lldb::SBDebugger::Create(true /*source_init_files*/);
+  auto arguments = request.getObject("arguments");
+  const auto skipInitFiles = GetBoolean(arguments, "skipInitFiles", false);
+  g_vsc.debugger =
+      lldb::SBDebugger::Create(!skipInitFiles /*source_init_files*/);
   // Create an empty target right away since we might get breakpoint requests
   // before we are given an executable to launch in a "launch" request, or a
   // executable when attaching to a process by process ID in a "attach"
   // request.
   FILE *out = llvm::sys::RetryAfterSignal(nullptr, fopen, dev_null_path, "w");
   if (out) {
     // Set the output and error file handles to redirect into nothing otherwise
     // if any code in LLDB prints to the debugger file handles, the output and