Function ajaxHandleResponses

docs/welcome/js/jquery.js:8117–8175

( s, jqXHR, responses )

 * - returns the corresponding response
 */
function ajaxHandleResponses( s, jqXHR, responses ) {
    var firstDataType, ct, finalDataType, type,
        contents = s.contents,
        dataTypes = s.dataTypes,
        responseFields = s.responseFields;

    // Fill responseXXX fields
    for ( type in responseFields ) {
        if ( type in responses ) {
            jqXHR[ responseFields[type] ] = responses[ type ];
        }
    }

    // Remove auto dataType and get content-type in the process
    while( dataTypes[ 0 ] === "*" ) {
        dataTypes.shift();
        if ( ct === undefined ) {
            ct = s.mimeType || jqXHR.getResponseHeader("Content-Type");
        }
    }

    // Check if we're dealing with a known content-type
    if ( ct ) {
        for ( type in contents ) {
            if ( contents[ type ] && contents[ type ].test( ct ) ) {
                dataTypes.unshift( type );
                break;
            }
        }
    }

    // Check to see if we have a response for the expected dataType
    if ( dataTypes[ 0 ] in responses ) {
        finalDataType = dataTypes[ 0 ];
    } else {
        // Try convertible dataTypes
        for ( type in responses ) {
            if ( !dataTypes[ 0 ] || s.converters[ type + " " + dataTypes[0] ] ) {
                finalDataType = type;
                break;
            }
            if ( !firstDataType ) {
                firstDataType = type;
            }
        }
        // Or just use first one
        finalDataType = finalDataType || firstDataType;
    }

    // If we found a dataType
    // We add the dataType to the list if needed
    // and return the corresponding response
    if ( finalDataType ) {
        if ( finalDataType !== dataTypes[ 0 ] ) {
            dataTypes.unshift( finalDataType );
        }
        return responses[ finalDataType ];
    }