Add a frozen mode to update configuration

The frozen mode is used by the dependency lock file.

It makes sure that the resolution is always intransitive and that ivy
does not check for changed dependencies and stores that information in
the resolved ivy files. Following the ivy documentation, the last change
may bring a slight performance improvement:

http://ant.apache.org/ivy/history/latest-milestone/use/resolve.html

librarymanagement/src/main/contraband/librarymanagement.json

@@ -635,7 +635,8 @@
         { "name": "missingOk",      "type": "boolean"                                               },
         { "name": "logging",        "type": "sbt.librarymanagement.UpdateLogging"                   },
         { "name": "artifactFilter", "type": "sbt.librarymanagement.ArtifactTypeFilter"              },
-        { "name": "offline",        "type": "boolean"                                               }
+        { "name": "offline",        "type": "boolean"                                               },
+        { "name": "frozen",         "type": "boolean"                                               }
       ]
     },
     {

librarymanagement/src/main/scala/sbt/internal/librarymanagement/IvyActions.scala

@@ -469,6 +469,10 @@ object IvyActions {
     resolveOptions.setArtifactFilter(updateConfiguration.artifactFilter)
     resolveOptions.setUseCacheOnly(updateConfiguration.offline)
     resolveOptions.setLog(ivyLogLevel(logging))
+    if (updateConfiguration.frozen) {
+      resolveOptions.setTransitive(false)
+      resolveOptions.setCheckIfChanged(false)
+    }
     ResolutionCache.cleanModule(
       moduleDescriptor.getModuleRevisionId,
       resolveId,
@@ -522,6 +526,10 @@ object IvyActions {
     resolveOptions.setArtifactFilter(updateConfiguration.artifactFilter)
     resolveOptions.setUseCacheOnly(updateConfiguration.offline)
     resolveOptions.setLog(ivyLogLevel(updateConfiguration.logging))
+    if (updateConfiguration.frozen) {
+      resolveOptions.setTransitive(false)
+      resolveOptions.setCheckIfChanged(false)
+    }
     val acceptError = updateConfiguration.missingOk
     resolver.customResolve(descriptor, acceptError, logicalClock, resolveOptions, cache, log)
   }

librarymanagement/src/main/scala/sbt/librarymanagement/DefaultLibraryManagement.scala

@@ -69,6 +69,7 @@ class DefaultLibraryManagement(ivyConfiguration: IvyConfiguration, log: Logger)
       true,
       UpdateLogging.DownloadOnly,
       artifactFilter,
+      false,
       false
     )
 

librarymanagement/src/test/scala/BaseIvySpecification.scala

@@ -74,7 +74,8 @@ trait BaseIvySpecification extends UnitSpec {
                         false,
                         UpdateLogging.Full,
                         ArtifactTypeFilter.forbid(Set("src", "doc")),
-                        offline)
+                        offline,
+                        false)
   }
 
   def ivyUpdateEither(module: IvySbt#Module): Either[UnresolvedWarning, UpdateReport] = {

librarymanagement/src/test/scala/FrozenModeSpec.scala

@@ -0,0 +1,55 @@
+package sbt.librarymanagement
+
+import sbt.internal.librarymanagement._
+import sbt.internal.librarymanagement.impl.DependencyBuilders
+
+class FrozenModeSpec extends BaseIvySpecification with DependencyBuilders {
+  private final val targetDir = Some(currentDependency)
+  private final val onlineConf = makeUpdateConfiguration(false)
+  private final val frozenConf = makeUpdateConfiguration(false).withFrozen(true)
+  private final val noClock = LogicalClock.unknown
+  private final val warningConf = UnresolvedWarningConfiguration()
+  private final val normalOptions = UpdateOptions()
+
+  final val stoml = Vector("me.vican.jorge" % "stoml_2.12" % "0.4" % "compile")
+
+  /* https://repo1.maven.org/maven2/me/vican/jorge/stoml_2.12/0.4/stoml_2.12-0.4.jar
+   * https://repo1.maven.org/maven2/org/scala-lang/scala-library/2.12.0/scala-library-2.12.0.jar
+   * https://repo1.maven.org/maven2/com/lihaoyi/fastparse_2.12/0.4.2/fastparse_2.12-0.4.2.jar
+   * https://repo1.maven.org/maven2/com/lihaoyi/fastparse-utils_2.12/0.4.2/fastparse-utils_2.12-0.4.2.jar
+   * https://repo1.maven.org/maven2/com/lihaoyi/sourcecode_2.12/0.1.3/sourcecode_2.12-0.1.3.jar */
+  final val explicitStoml = Vector(
+    "me.vican.jorge" % "stoml_2.12" % "0.4" % "compile",
+    "org.scala-lang" % "scala-library" % "2.12.0" % "compile",
+    "com.lihaoyi" % "fastparse_2.12" % "0.4.2" % "compile",
+    "com.lihaoyi" % "fastparse-utils_2.12" % "0.4.2" % "compile",
+    "com.lihaoyi" % "sourcecode_2.12" % "0.1.3" % "compile"
+  )
+
+  it should "fail when artifacts are missing in the cache" in {
+    cleanIvyCache()
+    def update(module: IvySbt#Module, conf: UpdateConfiguration) =
+      IvyActions.updateEither(module, conf, warningConf, noClock, targetDir, log)
+
+    val toResolve = module(defaultModuleId, stoml, None, normalOptions)
+    val onlineResolution = update(toResolve, onlineConf)
+    assert(onlineResolution.isRight)
+    val numberResolved = onlineResolution.right.get.allModules.size
+
+    cleanIvyCache()
+    val singleFrozenResolution = update(toResolve, frozenConf)
+    assert(singleFrozenResolution.isRight)
+    assert(
+      singleFrozenResolution.right.get.allModules.size == 1,
+      s"The number of explicit modules in frozen mode should 1"
+    )
+
+    cleanIvyCache()
+    // This relies on the fact that stoml has 5 transitive dependencies
+    val toExplicitResolve = module(defaultModuleId, explicitStoml, None, normalOptions)
+    val frozenResolution = update(toExplicitResolve, frozenConf)
+    assert(frozenResolution.isRight)
+    assert(frozenResolution.right.get.allModules.size == numberResolved,
+           s"The number of explicit modules in frozen mode should be equal than $numberResolved")
+  }
+}