From 42e094b98b4aa82c3c998658aa69e003114840e2 Mon Sep 17 00:00:00 2001
From: Dmitry Zhuravlev <dmitry.zhuravlev@jetbrains.com>
Date: Tue, 9 Oct 2018 19:00:19 +0300
Subject: [PATCH] vcs: new implementation for assertContainsOrdered

Previous implementation uses retainAll. It is not perfectly match the case if we want to check if elements which is exist in "collection" list contains in the same order in "expected" list.
---
 .../testFramework/UsefulTestCase.java         | 20 +++++++++++--
 .../git4idea/ignore/GitIgnoredFileTest.kt     | 29 +------------------
 2 files changed, 18 insertions(+), 31 deletions(-)

diff --git a/platform/testFramework/src/com/intellij/testFramework/UsefulTestCase.java b/platform/testFramework/src/com/intellij/testFramework/UsefulTestCase.java
index 4948bf1bde36..b166528085f9 100644
--- a/platform/testFramework/src/com/intellij/testFramework/UsefulTestCase.java
+++ b/platform/testFramework/src/com/intellij/testFramework/UsefulTestCase.java
@@ -31,6 +31,8 @@ import com.intellij.testFramework.exceptionCases.AbstractExceptionCase;
 import com.intellij.testFramework.fixtures.IdeaTestExecutionPolicy;
 import com.intellij.util.*;
 import com.intellij.util.containers.ContainerUtil;
+import com.intellij.util.containers.PeekableIterator;
+import com.intellij.util.containers.PeekableIteratorWrapper;
 import com.intellij.util.containers.hash.HashMap;
 import com.intellij.util.lang.CompoundRuntimeException;
 import com.intellij.util.ui.UIUtil;
@@ -43,6 +45,7 @@ import org.jetbrains.annotations.Contract;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.junit.Assert;
+import org.junit.ComparisonFailure;
 
 import java.io.File;
 import java.io.FileNotFoundException;
@@ -559,9 +562,20 @@ public abstract class UsefulTestCase extends TestCase {
   }
 
   public static <T> void assertContainsOrdered(@NotNull Collection<? extends T> collection, @NotNull Collection<? extends T> expected) {
-    ArrayList<T> copy = new ArrayList<>(collection);
-    copy.retainAll(expected);
-    assertOrderedEquals(toString(collection), copy, expected);
+    PeekableIterator<T> expectedIt = new PeekableIteratorWrapper<>(expected.iterator());
+    PeekableIterator<T> actualIt = new PeekableIteratorWrapper<>(collection.iterator());
+
+    while (actualIt.hasNext() && expectedIt.hasNext()) {
+      T expectedElem = expectedIt.peek();
+      T actualElem = actualIt.peek();
+      if (expectedElem.equals(actualElem)) {
+        expectedIt.next();
+      }
+      actualIt.next();
+    }
+    if (expectedIt.hasNext()) {
+      throw new ComparisonFailure("", toString(expected), toString(collection));
+    }
   }
 
   @SafeVarargs
diff --git a/plugins/git4idea/tests/git4idea/ignore/GitIgnoredFileTest.kt b/plugins/git4idea/tests/git4idea/ignore/GitIgnoredFileTest.kt
index 95dc58c65e08..2174fe6a9f31 100644
--- a/plugins/git4idea/tests/git4idea/ignore/GitIgnoredFileTest.kt
+++ b/plugins/git4idea/tests/git4idea/ignore/GitIgnoredFileTest.kt
@@ -4,12 +4,10 @@ package git4idea.ignore
 import com.intellij.openapi.command.WriteCommandAction
 import com.intellij.openapi.vfs.VirtualFile
 import com.intellij.openapi.vfs.encoding.EncodingProjectManager
-import com.intellij.util.containers.PeekableIteratorWrapper
 import git4idea.GitUtil
 import git4idea.repo.GitRepositoryFiles.GITIGNORE
 import git4idea.test.GitPlatformTest
 import git4idea.test.createRepository
-import org.junit.Assert
 import java.io.File
 
 const val OUT = "out"
@@ -60,32 +58,7 @@ class GitIgnoredFileTest : GitPlatformTest() {
     val generatedGitIgnoreContent = gitIgnoreFile.readText(projectCharset)
     assertFalse("Generated ignore file is empty", generatedGitIgnoreContent.isBlank())
     assertFalse("Generated ignore file content should be system-independent", generatedGitIgnoreContent.contains('\\'))
-    assertIncludesAllOrdered(generatedGitIgnoreContent.lines(), gitIgnoreExpectedContentList)
-  }
-
-  private fun assertIncludesAllOrdered(actualList: List<String>, expectedList: List<String>) {
-    val expectedIt = PeekableIteratorWrapper(expectedList.iterator())
-    val actualIt = PeekableIteratorWrapper(actualList.iterator())
-
-    while (actualIt.hasNext() && expectedIt.hasNext()) {
-      val expected = expectedIt.peek()
-      val actual = actualIt.peek()
-      if (expected == actual) {
-        expectedIt.next()
-        actualIt.next()
-      }
-      else {
-        actualIt.next()
-      }
-    }
-
-    if(expectedIt.hasNext()){
-      Assert.fail("""
-         Expected: $expectedList
-         Actual: $actualList
-         Not included in the same order.
-      """.trimIndent())
-    }
+    assertContainsOrdered(generatedGitIgnoreContent.lines(), gitIgnoreExpectedContentList)
   }
 
   private fun VirtualFile.findOrCreateDir(dirName: String) = this.findChild(dirName) ?: createChildDirectory(this, dirName)