dist/vue-resource.esm.js
function method (request) {

    if (request.emulateHTTP && /^(PUT|PATCH|DELETE)$/i.test(request.method)) {
        request.headers.set('X-HTTP-Method-Override', request.method);
        request.method = 'POST';
    }

}
function method (request) {

    if (request.emulateHTTP && /^(PUT|PATCH|DELETE)$/i.test(request.method)) {
        request.headers.set('X-HTTP-Method-Override', request.method);
        request.method = 'POST';
    }

}
function method ( request ) { if ( request . emulateHTTP && / ^(PUT|PATCH|DELETE)$ / i . test ( request . method ) ) { request . headers . set ( 'X-HTTP-Method-Override' , request . method ) ; request . method = 'POST' ; } }
HTTP method override Interceptor.
HTTP method override Interceptor .