From c77130d0f3855355e63d6d4eedc21e70258d4a12 Mon Sep 17 00:00:00 2001
From: Vyacheslav Gerasimov <vyacheslav.gerasimov@jetbrains.com>
Date: Mon, 2 Mar 2020 22:13:54 +0300
Subject: [PATCH] Build: Add test for reporting all gradle build cache misses

`kotlin.build.cache.check.enabled` will be used for cacheability testing
on teamcity
---
 .idea/dictionaries/4u7.xml          |  2 +
 build.gradle.kts                    |  1 +
 gradle/checkCacheability.gradle.kts | 59 +++++++++++++++++++++++++++++
 3 files changed, 62 insertions(+)
 create mode 100644 gradle/checkCacheability.gradle.kts

diff --git a/.idea/dictionaries/4u7.xml b/.idea/dictionaries/4u7.xml
index ec16da6a994..6b2f1c7ec64 100644
--- a/.idea/dictionaries/4u7.xml
+++ b/.idea/dictionaries/4u7.xml
@@ -2,6 +2,8 @@
   <dictionary name="4u7">
     <words>
       <w>bintray</w>
+      <w>cacheability</w>
+      <w>cacheable</w>
       <w>cidr</w>
       <w>foldable</w>
       <w>instrumentator</w>
diff --git a/build.gradle.kts b/build.gradle.kts
index b77e4e90226..d9cddba45c9 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -149,6 +149,7 @@ rootProject.apply {
     from(rootProject.file("gradle/javaInstrumentation.gradle.kts"))
     from(rootProject.file("gradle/jps.gradle.kts"))
     from(rootProject.file("gradle/checkArtifacts.gradle.kts"))
+    from(rootProject.file("gradle/checkCacheability.gradle.kts"))
 }
 
 IdeVersionConfigurator.setCurrentIde(project)
diff --git a/gradle/checkCacheability.gradle.kts b/gradle/checkCacheability.gradle.kts
new file mode 100644
index 00000000000..fcb1acef476
--- /dev/null
+++ b/gradle/checkCacheability.gradle.kts
@@ -0,0 +1,59 @@
+import org.gradle.api.internal.GeneratedSubclasses
+import org.gradle.api.internal.TaskInternal
+
+val checkCacheability = findProperty("kotlin.build.cache.check.enabled") as String? == "true"
+val isTeamcityBuild = project.hasProperty("teamcity") || System.getenv("TEAMCITY_VERSION") != null
+
+if (checkCacheability && buildCacheEnabled()) {
+    gradle.taskGraph.afterTask {
+        if (isCacheable()) {
+            if (isTeamcityBuild)
+                testStarted(path)
+
+            if (!state.skipped)
+                reportCacheMiss()
+
+            if (isTeamcityBuild)
+                testFinished(path)
+        }
+    }
+}
+
+fun Task.reportCacheMiss() {
+    if (isTeamcityBuild)
+        testFailed(path, "Build cache MISS", "$path task outputs expected to be taken from Gradle build cache")
+    else
+        println("BUILD CACHE MISS - $path")
+}
+
+fun Project.buildCacheEnabled() = gradle.startParameter.isBuildCacheEnabled
+
+fun Task.isCacheable(): Boolean {
+    this as TaskInternal
+    return cachingEnabled() && !cachingDisabled()
+}
+
+fun TaskInternal.cachingEnabled(): Boolean {
+    return if (outputs.cacheIfSpecs.isEmpty())
+        GeneratedSubclasses.unpackType(this).isAnnotationPresent(CacheableTask::class.java)
+    else
+        outputs.cacheIfSpecs.all { it.invoke(this) }
+}
+
+fun TaskInternal.cachingDisabled(): Boolean = outputs.doNotCacheIfSpecs.any { it.invoke(this) }
+
+fun escape(s: String): String {
+    return s.replace("[\\|'\\[\\]]".toRegex(), "\\|$0").replace("\n".toRegex(), "|n").replace("\r".toRegex(), "|r")
+}
+
+fun testStarted(testName: String) {
+    println("##teamcity[testStarted name='%s']".format(escape(testName)))
+}
+
+fun testFinished(testName: String) {
+    println("##teamcity[testFinished name='%s']".format(escape(testName)))
+}
+
+fun testFailed(name: String, message: String, details: String) {
+    println("##teamcity[testFailed name='%s' message='%s' details='%s']".format(escape(name), escape(message), escape(details)))
+}
\ No newline at end of file