# Testing

| [`testing.assert_equal`](../generated/xarray.testing.assert_equal.html.md#xarray.testing.assert_equal)(a, b[, check_dim_order])       | Like [`numpy.testing.assert_array_equal()`](https://numpy.org/doc/stable/reference/generated/numpy.testing.assert_array_equal.html#numpy.testing.assert_array_equal), but for xarray objects.   |
|----------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [`testing.assert_identical`](../generated/xarray.testing.assert_identical.html.md#xarray.testing.assert_identical)(a, b)                  | Like [`xarray.testing.assert_equal()`](../generated/xarray.testing.assert_equal.html.md#xarray.testing.assert_equal), but also matches the objects' names and attributes.                            |
| [`testing.assert_allclose`](../generated/xarray.testing.assert_allclose.html.md#xarray.testing.assert_allclose)(a, b[, rtol, atol, ...]) | Like [`numpy.testing.assert_allclose()`](https://numpy.org/doc/stable/reference/generated/numpy.testing.assert_allclose.html#numpy.testing.assert_allclose), but for xarray objects.            |
| [`testing.assert_chunks_equal`](../generated/xarray.testing.assert_chunks_equal.html.md#xarray.testing.assert_chunks_equal)(a, b)            | Assert that chunksizes along chunked dimensions are equal.                                                                                                                                      |

Test that two `DataTree` objects are similar.

| [`testing.assert_isomorphic`](../generated/xarray.testing.assert_isomorphic.html.md#xarray.testing.assert_isomorphic)(a, b)          | Two DataTrees are considered isomorphic if the set of paths to their descendent nodes are the same.                                                                                           |
|----------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [`testing.assert_equal`](../generated/xarray.testing.assert_equal.html.md#xarray.testing.assert_equal)(a, b[, check_dim_order]) | Like [`numpy.testing.assert_array_equal()`](https://numpy.org/doc/stable/reference/generated/numpy.testing.assert_array_equal.html#numpy.testing.assert_array_equal), but for xarray objects. |
| [`testing.assert_identical`](../generated/xarray.testing.assert_identical.html.md#xarray.testing.assert_identical)(a, b)            | Like [`xarray.testing.assert_equal()`](../generated/xarray.testing.assert_equal.html.md#xarray.testing.assert_equal), but also matches the objects' names and attributes.                          |

# Hypothesis Testing Strategies

See the [documentation page on testing](../user-guide/testing.html.md#testing-hypothesis) for a guide on how to use these strategies.

#### WARNING
These strategies should be considered highly experimental, and liable to change at any time.

| [`testing.strategies.supported_dtypes`](../generated/xarray.testing.strategies.supported_dtypes.html.md#xarray.testing.strategies.supported_dtypes)()         | Generates only those numpy dtypes which xarray can handle.              |
|-------------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------|
| [`testing.strategies.names`](../generated/xarray.testing.strategies.names.html.md#xarray.testing.strategies.names)()                               | Generates arbitrary string names for dimensions / variables.            |
| [`testing.strategies.dimension_names`](../generated/xarray.testing.strategies.dimension_names.html.md#xarray.testing.strategies.dimension_names)(\*[, ...])  | Generates an arbitrary list of valid dimension names.                   |
| [`testing.strategies.dimension_sizes`](../generated/xarray.testing.strategies.dimension_sizes.html.md#xarray.testing.strategies.dimension_sizes)(\*[, ...])  | Generates an arbitrary mapping from dimension names to lengths.         |
| [`testing.strategies.attrs`](../generated/xarray.testing.strategies.attrs.html.md#xarray.testing.strategies.attrs)()                               | Generates arbitrary valid attributes dictionaries for xarray objects.   |
| [`testing.strategies.variables`](../generated/xarray.testing.strategies.variables.html.md#xarray.testing.strategies.variables)(\*[, ...])              | Generates arbitrary xarray.Variable objects.                            |
| [`testing.strategies.unique_subset_of`](../generated/xarray.testing.strategies.unique_subset_of.html.md#xarray.testing.strategies.unique_subset_of)(objs, \*) | Return a strategy which generates a unique subset of the given objects. |