From 324ffe835e863380ff617f0d1d47080a2ef65903 Mon Sep 17 00:00:00 2001
From: Aleksey Pivovarov <AMPivovarov@gmail.com>
Date: Mon, 23 Apr 2018 14:58:44 +0300
Subject: [PATCH] icons.gant: check that all fallback icons are replaced with
 stub.png

---
 .../build/images/ImageSanityChecker.kt        | 36 +++++++++++++++----
 .../jetbrains/intellij/build/images/util.kt   |  9 +++++
 2 files changed, 39 insertions(+), 6 deletions(-)

diff --git a/platform/build-scripts/icons/src/org/jetbrains/intellij/build/images/ImageSanityChecker.kt b/platform/build-scripts/icons/src/org/jetbrains/intellij/build/images/ImageSanityChecker.kt
index 8ab81559f3ba..801736f09f75 100644
--- a/platform/build-scripts/icons/src/org/jetbrains/intellij/build/images/ImageSanityChecker.kt
+++ b/platform/build-scripts/icons/src/org/jetbrains/intellij/build/images/ImageSanityChecker.kt
@@ -24,6 +24,8 @@ import java.io.File
 import java.util.*
 
 abstract class ImageSanityCheckerBase(val projectHome: File, val ignoreSkipTag: Boolean) {
+  private val STUB_PNG_MD5 = "5a87124746c39b00aad480e92672eca0" // /actions/stub.svg - 16x16
+
   fun check(module: JpsModule) {
     val allImages = ImageCollector(projectHome, false, ignoreSkipTag).collect(module)
 
@@ -34,7 +36,8 @@ abstract class ImageSanityCheckerBase(val projectHome: File, val ignoreSkipTag:
     checkHaveCompleteIconSet(images, module)
     checkHaveValidSize(images, module)
     checkAreNotAmbiguous(images, module)
-    checkSvgIconsFallbackVersions(images, module)
+    checkSvgFallbackVersionsAreStubIcons(images, module)
+    checkOverridingFallbackVersionsAreStubIcons(images, module)
   }
 
   private fun checkHaveRetinaVersion(images: List<ImagePaths>, module: JpsModule) {
@@ -83,14 +86,35 @@ abstract class ImageSanityCheckerBase(val projectHome: File, val ignoreSkipTag:
     }
   }
 
-  private fun checkSvgIconsFallbackVersions(images: List<ImagePaths>, module: JpsModule) {
-    process(images, WARNING, "svg image with non-fallback legacy version", module) { image ->
-      val extensions = image.files.map { ImageExtension.fromFile(it) }
-      if (SVG !in extensions) return@process true
-      return@process image.files.filter { ImageExtension.fromFile(it) != SVG }.filter { ImageType.fromFile(it) != BASIC }.isEmpty()
+  private fun checkSvgFallbackVersionsAreStubIcons(images: List<ImagePaths>, module: JpsModule) {
+    process(images, WARNING, "SVG icons should use stub.png as fallback", module) { image ->
+      if (image.files.none { ImageExtension.fromFile(it) == SVG }) return@process true
+
+      val legacyFiles = image.files.filter { ImageExtension.fromFile(it) != SVG }
+      return@process isStubFallbackVersion(legacyFiles)
     }
   }
 
+  private fun checkOverridingFallbackVersionsAreStubIcons(images: List<ImagePaths>, module: JpsModule) {
+    process(images, WARNING, "Overridden icons should be replaced with stub.png as fallback", module) { image ->
+      if (image.deprecationReplacement == null) return@process true
+
+      return@process isStubFallbackVersion(image.files)
+    }
+  }
+
+  private fun isStubFallbackVersion(files: List<File>): Boolean {
+    if (files.isEmpty()) return true
+    if (files.size > 1) return false
+
+    val file = files.single()
+    if (ImageType.fromFile(file) != BASIC) return false
+
+    val md5 = md5(file)
+    return md5 == STUB_PNG_MD5
+  }
+
+
   private fun process(images: List<ImagePaths>, severity: Severity, message: String, module: JpsModule,
                       processor: (ImagePaths) -> Boolean) {
     val result = ArrayList<ImagePaths>()
diff --git a/platform/build-scripts/icons/src/org/jetbrains/intellij/build/images/util.kt b/platform/build-scripts/icons/src/org/jetbrains/intellij/build/images/util.kt
index de07674838a0..f93e3f8c3cdb 100644
--- a/platform/build-scripts/icons/src/org/jetbrains/intellij/build/images/util.kt
+++ b/platform/build-scripts/icons/src/org/jetbrains/intellij/build/images/util.kt
@@ -20,6 +20,8 @@ import com.intellij.util.SVGLoader
 import java.awt.Dimension
 import java.awt.Image
 import java.io.File
+import java.math.BigInteger
+import java.security.MessageDigest
 import javax.imageio.ImageIO
 
 internal val File.children: List<File> get() = if (isDirectory) listFiles().toList() else emptyList()
@@ -63,6 +65,13 @@ internal fun loadImage(file: File): Image? {
   }
 }
 
+internal fun md5(file: File): String {
+  val md5 = MessageDigest.getInstance("MD5")
+  val bytes = file.inputStream().readBytes()
+  val hash = md5.digest(bytes)
+  return BigInteger(hash).abs().toString(16)
+}
+
 internal enum class ImageType(private val suffix: String) {
   BASIC(""), RETINA("@2x"), DARCULA("_dark"), RETINA_DARCULA("@2x_dark");