Nil pointer error when triggering code completion before the first top level node #314
Description
If we trigger code completion one space after the front of the line, a nil pointer will be triggered.
services:{
"textDocument": {
"uri": "file:///tmp/compose.yaml"
},
"position": {
"line": 0,
"character": 1
},
"context": {
"triggerKind": 1
}
}runtime.errorString runtime error: invalid memory address or nil pointer dereference
/home/runner/work/docker-language-server/docker-language-server/internal/pkg/server/server.go:218 (*Server).handleRecovered
/home/runner/work/docker-language-server/docker-language-server/internal/pkg/server/server.go:131 NewServer.func1
/home/runner/work/docker-language-server/docker-language-server/internal/tliron/glsp/protocol/handler.go:100 (*Handler).Handle.func1
runtime/panic.go:792 gopanic
runtime/signal_windows.go:401 sigpanic
/home/runner/work/docker-language-server/docker-language-server/internal/compose/completion.go:585 walkNodes
/home/runner/work/docker-language-server/docker-language-server/internal/compose/completion.go:578 NodeStructure
/home/runner/work/docker-language-server/docker-language-server/internal/compose/completion.go:547 constructCompletionNodePath
/home/runner/work/docker-language-server/docker-language-server/internal/compose/completion.go:207 Completion
/home/runner/work/docker-language-server/docker-language-server/internal/pkg/server/completion.go:22 (*Server).TextDocumentCompletion
/home/runner/work/docker-language-server/docker-language-server/internal/tliron/glsp/protocol/handler.go:388 (*Handler).Handle
/home/runner/work/docker-language-server/docker-language-server/internal/tliron/glsp/server/handler.go:48 (*Server).handle
github.com/sourcegraph/jsonrpc2@v0.2.0/handler_with_error.go:21 (*HandlerWithErrorConfigurer).Handle
github.com/sourcegraph/jsonrpc2@v0.2.0/conn.go:205 (*Conn).readMessages