1. A computer-implemented method comprising: receiving, by one or more computing devices, data identifying a portion of a lane line detected in a vehicle's environment, the data including location coordinates for the portion of the lane line; identifying, by the one or more computing devices, a corresponding feature for the lane line from pre-stored map information based on the location coordinates and a map location of the corresponding feature, wherein the corresponding feature is defined as a curve and associated with a tag identifying a type of the corresponding feature; identifying, by the one or more computing devices, a tolerance constraint based on the tag identifying the type of the corresponding feature; dividing, by the one or more computing devices, the portion of the lane line into two or more line segments, each line segment of the two or more line segments having a first position; changing, by the one or more computing devices, the first position of one of the two or more line segments to determine a second position of the one of the two or more line segments based on the location coordinates and the tolerance constraint, wherein changing the first position includes at least one of shifting in a lateral manner or rotating in an angular manner the first position of the one of the two or more line segments towards a position of a corresponding portion of the curve; determining, by the one or more computing devices, a value based on a comparison of the first position to the second position, wherein the value indicates a likelihood that the corresponding feature has changed; and using, by the one or more processors, the value to maneuver the vehicle in an autonomous driving mode.