IDEA-148477 Handle AssertJ assertions in the same way as JUnit assertions

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/HardcodedContracts.java

@@ -37,6 +37,8 @@ public class HardcodedContracts {
 
     final int paramCount = method.getParameterList().getParametersCount();
     String className = owner.getQualifiedName();
+    if (className == null) return Collections.emptyList();
+
     String methodName = method.getName();
 
     if ("java.lang.System".equals(className)) {
@@ -76,6 +78,7 @@ public class HardcodedContracts {
              "org.junit.Assert".equals(className) ||
              "junit.framework.TestCase".equals(className) ||
              "com.google.common.truth.Truth".equals(className) ||
+             className.startsWith("org.assertj.core.api.") ||
              "org.testng.Assert".equals(className) ||
              "org.testng.AssertJUnit".equals(className)) {
       return handleTestFrameworks(paramCount, className, methodName, call);

java/java-tests/testData/inspection/dataFlow/fixture/AssertThat.java

@@ -1,5 +1,6 @@
 import org.hamcrest.CoreMatchers;
 import org.jetbrains.annotations.Nullable;
+import org.assertj.core.api.Assertions;
 import static org.hamcrest.CoreMatchers.*;
 import static org.junit.Assert.assertThat;
 
@@ -15,4 +16,9 @@ class Contracts {
     int length = test.length();
   }
 
+  public void checkAssertJ(@Nullable Object object) {
+    Assertions.assertThat(object).isNotNull();
+    System.out.println(object.toString());
+  }
+
 }

java/java-tests/testSrc/com/intellij/codeInspection/DataFlowInspectionTest.java

@@ -388,6 +388,14 @@ public class DataFlowInspectionTest extends DataFlowInspectionTestCase {
                        "public static <T> void assertThat(T actual, org.hamcrest.Matcher<? super T> matcher) {}\n" +
                        "public static <T> void assertThat(String msg, T actual, org.hamcrest.Matcher<? super T> matcher) {}\n" +
                        "}");
+
+    myFixture.addClass("package org.assertj.core.api; public class Assertions { " +
+                       "public static <T> AbstractObjectAssert<?, T> assertThat(Object actual) {}\n" +
+                       "}");
+    myFixture.addClass("package org.assertj.core.api; public class AbstractObjectAssert<S extends AbstractObjectAssert<S, A>, A> {" +
+                       "public S isNotNull() {}" +
+                       "}");
+
     myFixture.enableInspections(new DataFlowInspection());
     myFixture.testHighlighting(true, false, true, getTestName(false) + ".java");
   }