[[rel5.0:dependency_constraints]]
=== [5.0] Improved support for dependency and version constraints

Through the Gradle 4.x release stream, new `@Incubating` features were added to the dependency resolution engine.
These include sophisticated version constraints (`prefer`, `strictly`, `reject`), dependency constraints, and `platform` dependencies.

            }
        }

        @Override
        public ModelSource resolveModel(Session session, Dependency dependency, AtomicReference<Dependency> modified)
                throws ModelResolverException {
            try {
                org.apache.maven.model.Dependency d = new org.apache.maven.model.Dependency(dependency);
                InternalSession internalSession = InternalSession.from(session);

	//
	// The direct map is keyed by module paths, not module versions. When a
	// module's selected version changes, we assume that it remains direct if the
	// previous version was a direct dependency. That assumption might not hold in
	// rare cases (such as if a dependency splits out a nested module, or merges a
	// nested module back into a parent module).
	direct map[string]bool

	graphOnce sync.Once // guards writes to (but not reads from) graph

public operator fun DependencyAdder.invoke(dependency: Dependency): Unit defined in org.gradle.kotlin.dsl
public operator fun DependencyAdder.invoke(files: FileCollection): Unit defined in org.gradle.kotlin.dsl
public operator fun DependencyAdder.invoke(dependency: Provider<out Dependency>): Unit defined in org.gradle.kotlin.dsl

    constant is included for completeness.
 *  New: Upgrade to Okio 1.14.0.

     ```xml
     <dependency>
       <groupId>com.squareup.okio</groupId>
       <artifactId>okio</artifactId>
       <version>1.14.0</version>
     </dependency>

     com.squareup.okio:okio:1.14.0
     ```

 *  Fix: Handle `HTTP/1.1 100 Continue` status lines, even on requests that did

                // we are currently adding a configuration to either an include, exclude or artifact
                // element
                // of a dependency. This means that we have to add this element to the corresponding
                // conf
                // of the current dependency descriptor
                if (confAware instanceof DependencyArtifactDescriptor) {

.Adding a dependency on test fixtures of an external library
====
include::sample[dir="snippets/java/fixtures/kotlin",files="build.gradle.kts[tags=external-test-fixtures-dependency]"]
include::sample[dir="snippets/java/fixtures/groovy",files="build.gradle[tags=external-test-fixtures-dependency]"]
====

Such a library dependency can be added to a source set associated with the `executable` component:

=== Example: Providing a library dependency to the source set

[source.multi-language-sample,groovy,indent=0]
.build.gradle
----
include::{snippetsPath}/native-binaries/cpp/groovy/build.gradle[tag=source-library]
----

    /**
     * Returns the dependency handler of this project. The returned dependency handler instance can be used for adding
     * new dependencies. For accessing already declared dependencies, the configurations can be used.
     *
     * <h3>Examples:</h3>
     * See docs for {@link DependencyHandler}
     *
     * @return the dependency handler. Never returns null.
     * @see #getConfigurations()

    tf_device.return
  }) {cluster_attr = "cluster_attr"} : () -> ()
  func.return
}

// Check that when two different IfRegion groups are overlapped and there is no
// control dependency or data dependency, both of the groups can be merged

// CHECK-LABEL: func @two_overlapped_if_groups_with_no_dependency_merged
func.func @two_overlapped_if_groups_with_no_dependency_merged() {
  // CHECK:      tf_device.cluster