From 2edc2a500e070acccd3b5727b7177bbca8bdca16 Mon Sep 17 00:00:00 2001
From: tbreisacher <tbreisacher@google.com>
Date: Mon, 26 Feb 2018 16:39:27 -0800
Subject: [PATCH] Disallow nulls in assertTypeEquals()

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=187101439
---
 .../javascript/rhino/testing/Asserts.java     | 47 ++++++++-----------
 ...ClosureReverseAbstractInterpreterTest.java | 19 ++++----
 2 files changed, 30 insertions(+), 36 deletions(-)

diff --git a/src/com/google/javascript/rhino/testing/Asserts.java b/src/com/google/javascript/rhino/testing/Asserts.java
index 74250447451..6cc37bcc430 100644
--- a/src/com/google/javascript/rhino/testing/Asserts.java
+++ b/src/com/google/javascript/rhino/testing/Asserts.java
@@ -39,17 +39,15 @@
 
 package com.google.javascript.rhino.testing;
 
+import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.truth.Truth.assertThat;
-import static org.junit.Assert.assertEquals;
 
 import com.google.common.collect.Iterables;
 import com.google.javascript.rhino.ErrorReporter;
 import com.google.javascript.rhino.jstype.JSType;
 import com.google.javascript.rhino.jstype.StaticTypedScope;
-
-import org.junit.Assert;
-
 import java.util.Iterator;
+import org.junit.Assert;
 
 /**
  * Helper methods for making assertions about the validity of types.
@@ -69,12 +67,10 @@ public static JSType assertValidResolve(JSType type) {
   }
 
   /** @return The resolved type */
-  public static JSType assertValidResolve(
-      JSType type, StaticTypedScope<JSType> scope) {
+  public static JSType assertValidResolve(JSType type, StaticTypedScope<JSType> scope) {
     ErrorReporter t = TestErrorReporter.forNoExpectedReports();
     JSType resolvedType = type.resolve(t, scope);
-    assertTypeEquals("JSType#resolve should not affect object equality",
-        type, resolvedType);
+    assertTypeEquals("JSType#resolve should not affect object equality", type, resolvedType);
     return resolvedType;
   }
 
@@ -84,14 +80,14 @@ public static void assertTypeNotEquals(JSType a, JSType b) {
 
   public static void assertTypeNotEquals(String message, JSType a, JSType b) {
     Assert.assertFalse(
-        message +
-        (message.isEmpty() ? "" : "\n") +
-        "Type: " + b + "\n",
+        message + (message.isEmpty() ? "" : "\n")
+            + " Equals is not symmetric.\n"
+            + "Type: " + b + "\n",
         a.isEquivalentTo(b));
     Assert.assertFalse(
-        message +
-        " Equals is not symmetric.\n" +
-        "Type: " + b + "\n",
+        message + (message.isEmpty() ? "" : "\n")
+            + " Equals is not symmetric.\n"
+            + "Type: " + b + "\n",
         b.isEquivalentTo(a));
   }
 
@@ -100,23 +96,18 @@ public static void assertTypeEquals(JSType a, JSType b) {
   }
 
   public static void assertTypeEquals(String message, JSType a, JSType b) {
-    assertEquals(
-        "Both types must be null, or both must be non-null " + a + "," + b,
-        (b == null), (a == null));
-    if (a == null) {
-      return;
-    }
+    checkNotNull(a);
+    checkNotNull(b);
     Assert.assertTrue(
-        message +
-        (message.isEmpty() ? "" : "\n") +
-        "Expected: " + a + "\n" +
-        "Actual  : " + b,
+        message + (message.isEmpty() ? "" : "\n")
+            + "Expected: " + a + "\n"
+            + "Actual  : " + b,
         a.isEquivalentTo(b));
     Assert.assertTrue(
-        message +
-        " Equals is not symmetric.\n" +
-        "Expected: " + b + "\n" +
-        "Actual  : " + a,
+        message
+            + " Equals is not symmetric.\n"
+            + "Expected: " + b + "\n"
+            + "Actual  : " + a,
         b.isEquivalentTo(a));
   }
 
diff --git a/test/com/google/javascript/jscomp/ClosureReverseAbstractInterpreterTest.java b/test/com/google/javascript/jscomp/ClosureReverseAbstractInterpreterTest.java
index e559009c2c0..5eda5cdb3c4 100644
--- a/test/com/google/javascript/jscomp/ClosureReverseAbstractInterpreterTest.java
+++ b/test/com/google/javascript/jscomp/ClosureReverseAbstractInterpreterTest.java
@@ -16,6 +16,8 @@
 
 package com.google.javascript.jscomp;
 
+import static com.google.common.truth.Truth.assertThat;
+
 import com.google.javascript.jscomp.type.ClosureReverseAbstractInterpreter;
 import com.google.javascript.jscomp.type.FlowScope;
 import com.google.javascript.rhino.Node;
@@ -302,19 +304,20 @@ private void testClosureFunction(String function, JSType type,
     assertEquals(Token.NAME, name.getToken());
 
     flowScope.inferSlotType("a", type);
-    ClosureReverseAbstractInterpreter rai =
-        new ClosureReverseAbstractInterpreter(registry);
+    ClosureReverseAbstractInterpreter rai = new ClosureReverseAbstractInterpreter(registry);
 
     // trueScope
     Asserts.assertTypeEquals(
         trueType,
-        rai.getPreciserScopeKnowingConditionOutcome(call, flowScope, true)
-        .getSlot("a").getType());
+        rai.getPreciserScopeKnowingConditionOutcome(call, flowScope, true).getSlot("a").getType());
 
     // falseScope
-    Asserts.assertTypeEquals(
-        falseType,
-        rai.getPreciserScopeKnowingConditionOutcome(call, flowScope, false)
-        .getSlot("a").getType());
+    JSType aType = rai.getPreciserScopeKnowingConditionOutcome(call, flowScope, false)
+        .getSlot("a").getType();
+    if (falseType == null) {
+      assertThat(aType).isNull();
+    } else {
+      Asserts.assertTypeEquals(falseType, aType);
+    }
   }
 }