This change ensures that a request containing query parameters in the
array format `someArray[]=value` can be bound into a simple array in
constructors, even for cases where the array values don't have nested
properties.
The value resolver is directly called in the constructor case, before
any mutable properties are considered or even cleared (see
`WebDataBinder#adaptEmptyArrayIndices` method). As a result, we need to
accommodate the possibility that the request stores array elements under
the `name[]` key rather than `name`. This change attempts a secondary
lookup with the `[]` suffix if the type is a list or array, and the key
doesn't include an index.
Closes gh-34121
This change ensures that DataBinder can bind constructor with a Map
parameter that has no nested properties, but just simple values like
a String: `someMap[0]=exampleString`.
Integration tests have been added to cover similar cases that use the
ServletRequestDataBinder.
Closes gh-34043
This change removes the `MultiValueMap` nature of `HttpHeaders`, since
it inherits APIs that do not align well with underlying server
implementations. Notably, methods that allows to iterate over the whole
collection of headers are susceptible to artificially introduced
duplicates when multiple casings are used for a given header, depending
on the underlying implementation.
This change includes a dedicated key set implementation to support
iterator-based removal, and either keeps map method implementations that
are relevant or introduces header-focused methods that have a similar
responsibility (like `hasHeaderValues(String, List)` and
`containsHeaderValue(String, String)`).
In order to nudge users away from using an HttpHeaders as a Map, the
`asSingleValueMap` view is deprecated. In order to offer an escape
hatch to users that do make use of the `MultiValueMap` API, a similar
`asMultiValueMap` view is introduced but is immediately marked as
deprecated.
This change also adds map-like but header-focused assertions to
`HttpHeadersAssert`, since it cannot extend `AbstractMapAssert` anymore.
Closes gh-33913
Stéphane Nicoll
Vladimir Perfilev
rstoyanchev
Sébastien Deleuze
Johnny Lim
Simon Baslé
Brenden Ehlers