Defer resolution of processor classpath

AGP doesn't like it being resolved during configuration time.

gradle-plugin/src/main/kotlin/com/google/devtools/ksp/gradle/KspSubplugin.kt

@@ -22,7 +22,6 @@ import org.gradle.api.Action
 import org.gradle.api.Project
 import org.gradle.api.Task
 import org.gradle.api.UnknownTaskException
-import org.gradle.api.artifacts.Configuration
 import org.gradle.api.attributes.Attribute
 import org.gradle.api.file.ConfigurableFileCollection
 import org.gradle.api.file.FileCollection
@@ -112,7 +111,6 @@ class KspGradleSubplugin @Inject internal constructor(private val registry: Tool
         private fun getSubpluginOptions(
             project: Project,
             kspExtension: KspExtension,
-            classpath: Configuration,
             sourceSetName: String,
             target: String,
             isIncremental: Boolean,
@@ -140,7 +138,6 @@ class KspGradleSubplugin @Inject internal constructor(private val registry: Tool
             )
             options += InternalSubpluginOption("projectBaseDir", project.project.projectDir.canonicalPath)
             options += SubpluginOption("allWarningsAsErrors", allWarningsAsErrors.toString())
-            options += FilesSubpluginOption("apclasspath", classpath.toList())
             // Turn this on by default to work KT-30172 around. It is off by default in the compiler plugin.
             options += SubpluginOption(
                 "returnOkOnError",
@@ -303,7 +300,6 @@ class KspGradleSubplugin @Inject internal constructor(private val registry: Tool
                     getSubpluginOptions(
                         project,
                         kspExtension,
-                        processorClasspath,
                         sourceSetName,
                         target,
                         isIncremental,
@@ -460,7 +456,7 @@ class KspGradleSubplugin @Inject internal constructor(private val registry: Tool
                                 getKspCachesDir(project, sourceSetName, target),
                                 project.provider { project.files() },
                                 project.provider { project.files() },
-                                project.provider { project.files() },
+                                project.provider { processorClasspath }
                             )
                         )
                     }
@@ -483,7 +479,7 @@ class KspGradleSubplugin @Inject internal constructor(private val registry: Tool
                                 getKspCachesDir(project, sourceSetName, target),
                                 project.provider { project.files() },
                                 project.provider { project.files() },
-                                project.provider { project.files() },
+                                project.provider { processorClasspath }
                             )
                         )
                     }
@@ -512,6 +508,7 @@ class KspGradleSubplugin @Inject internal constructor(private val registry: Tool
                             kspTask.compilerPluginOptions.addPluginArgument(kotlinCompileTask.compilerPluginOptions)
                         }
                         kspTask.commonSources.from(kotlinCompileTask.commonSources)
+                        kspTask.options.add(FilesSubpluginOption("apclasspath", processorClasspath.files.toList()))
                         val kspOptions = kspTask.options.get().flatMap { listOf("-P", it.toArg()) }
                         kspTask.compilerOptions.freeCompilerArgs.value(
                             kspOptions + kotlinCompileTask.compilerOptions.freeCompilerArgs.get()
@@ -726,6 +723,7 @@ internal fun createIncrementalChangesTransformer(
     processorCP: Provider<FileCollection>,
 ): (ChangedFiles) -> List<SubpluginOption> = { changedFiles ->
     val options = mutableListOf<SubpluginOption>()
+    val apClasspath = processorCP.get().files.toList()
     if (isKspIncremental) {
         if (isIntermoduleIncremental) {
             // findClasspathChanges may clear caches, if there are
@@ -736,7 +734,7 @@ internal fun createIncrementalChangesTransformer(
                 cacheDir,
                 classpathStructure.get().files,
                 libraries.get().files.toList(),
-                processorCP.get().files.toList()
+                apClasspath
             )
             options += classpathChanges.toSubpluginOptions()
         } else {
@@ -749,5 +747,7 @@ internal fun createIncrementalChangesTransformer(
     }
     options += changedFiles.toSubpluginOptions()
 
+    options += FilesSubpluginOption("apclasspath", apClasspath)
+
     options
 }

integration-tests/src/test/kotlin/com/google/devtools/ksp/test/AGP741IT.kt

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2020 Google LLC
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.devtools.ksp.test
+
+import org.gradle.testkit.runner.GradleRunner
+import org.junit.Assert
+import org.junit.Rule
+import org.junit.Test
+import java.io.File
+
+class AGP741IT {
+    @Rule
+    @JvmField
+    val project: TemporaryTestProject = TemporaryTestProject("playground-android-multi", "playground")
+
+    @Test
+    fun testDependencyResolutionCheck() {
+        val gradleRunner = GradleRunner.create().withProjectDir(project.root).withGradleVersion("7.6")
+
+        File(project.root, "gradle.properties").appendText("\nagpVersion=7.4.1")
+        gradleRunner.withArguments(":workload:compileDebugKotlin").build().let { result ->
+            Assert.assertFalse(result.output.contains("was resolved during configuration time."))
+        }
+    }
+}