Instead, you want to provide a different dependency that will be used only during tests (possibly only some specific tests), and will provide a value that can be used where the value of the original dependency was used.

### Use cases: external service { #use-cases-external-service }

An example could be that you have an external authentication provider that you need to call.

You send it a token and it returns an authenticated user.

	"github.com/google/uuid"
)

var testUUID = uuid.MustParse("f5c58c61-7175-4018-ab5e-a94fe9c2de4e")

func BenchmarkCrcHash(b *testing.B) {
	cases := []struct {
		key int
	}{
		{16},
		{64},
		{128},
		{256},
		{512},
		{1024},
	}
	for _, testCase := range cases {
		key := randString(testCase.key)
		b.Run("", func(b *testing.B) {
			b.SetBytes(1024)
			b.ReportAllocs()
			b.ResetTimer()
			for b.Loop() {

///

## Use cases { #use-cases }

Some use cases include:

* Converting non-JSON request bodies to JSON (e.g. <a href="https://msgpack.org/index.html" class="external-link" target="_blank">`msgpack`</a>).
* Decompressing gzip-compressed request bodies.
* Automatically logging all request bodies.

## Handling custom request body encodings { #handling-custom-request-body-encodings }

Of course, there are some cases where there's no problem in running the previous steps multiple times, in that case, it's a lot easier to handle.

/// tip

Also, keep in mind that depending on your setup, in some cases you **might not even need any previous steps** before starting your application.

In that case, you wouldn't have to worry about any of this. 🤷

///

   * may not occur at all. However, despite these limitations,
   * observed contention rates are typically low in these cases.
   *
   * It is possible for a Cell to become unused when threads that
   * once hashed to it terminate, as well as in the case where
   * doubling the table causes no thread to hash to it under
   * expanded mask.  We do not try to detect or remove such cells,

You probably read before that you can set a default [Response Status Code](../tutorial/response-status-code.md){.internal-link target=_blank}.

But in some cases you need to return a different status code than the default.

## Use case { #use-case }

For example, imagine that you want to return an HTTP status code of "OK" `200` by default.

Those parameters are what **FastAPI** will use to "solve" the dependency.

In both cases, it will have:

* An optional `q` query parameter that is a `str`.
* A `skip` query parameter that is an `int`, with a default of `0`.
* A `limit` query parameter that is an `int`, with a default of `100`.

In both cases the data will be converted, validated, documented on the OpenAPI schema, etc.

## Use it { #use-it }

				return
			}
		}
	}

	for idx, ownField := range ownForeignFields {
		joinFieldName := cases.Title(language.Und, cases.NoLower).String(schema.Name) + ownField.Name
		if len(joinForeignKeys) > idx {
			joinFieldName = cases.Title(language.Und, cases.NoLower).String(joinForeignKeys[idx])
		}

		ownFieldsMap[joinFieldName] = ownField
		fieldsMap[joinFieldName] = ownField

// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package cmd

import (
	"testing"
)

func TestSplitPath(t *testing.T) {
	cases := []struct {
		path                          string
		secondIndex                   bool
		expectedListKey, expectedItem string
	}{
		{"format.json", false, "format.json", ""},

		},
		{bucketName: "a", objName: "obj", PartID: 1, expectedError: fmt.Errorf("%s", "Bucket name invalid: a")},
		// Test case - 5.
		// Case with invalid object names.
		{bucketName: bucket, PartID: 1, expectedError: fmt.Errorf("%s", "Object name invalid: minio-bucket/")},
		// Test case - 6.
		// Valid object and bucket names but non-existent bucket.