Move foreign annotation tests into diagnostics folder

third-party/java8-annotations/org/jetbrains/annotations/NotNull.java

@@ -0,0 +1,44 @@
+/*
+ * Copyright 2000-2020 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.jetbrains.annotations;
+
+import java.lang.annotation.*;
+
+/**
+ * An element annotated with NotNull claims {@code null} value is <em>forbidden</em>
+ * to return (for methods), pass to (parameters) and hold (local variables and fields).
+ * Apart from documentation purposes this annotation is intended to be used by static analysis tools
+ * to validate against probable runtime errors and element contract violations.
+ */
+@Documented
+@Retention(RetentionPolicy.CLASS)
+@Target({ElementType.METHOD, ElementType.FIELD, ElementType.PARAMETER, ElementType.LOCAL_VARIABLE, ElementType.TYPE_USE})
+public @interface NotNull {
+    /**
+     * @return Custom exception message
+     */
+    String value() default "";
+
+    /**
+     * @return Custom exception type that should be thrown when not-nullity contract is violated.
+     * The exception class should have a constructor with one String argument (message).
+     *
+     * By default, {@link IllegalArgumentException} is thrown on null method arguments and
+     * {@link IllegalStateException} &mdash; on null return value.
+     */
+    Class<? extends Exception> exception() default Exception.class;
+}

third-party/java8-annotations/org/jetbrains/annotations/Nullable.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.annotations;
+
+import java.lang.annotation.*;
+
+/**
+ * An element annotated with {@link Nullable} claims {@code null} value is perfectly <em>valid</em>
+ * to return (for methods), pass to (parameters) or hold in (local variables and fields).
+ * Apart from documentation purposes this annotation is intended to be used by static analysis tools
+ * to validate against probable runtime errors or element contract violations.
+ * <br>
+ * By convention, this annotation applied only when the value should <em>always</em> be checked against {@code null}
+ * because the developer could do nothing to prevent null from happening.
+ * Otherwise, too eager {@link Nullable} usage could lead to too many false positives from static analysis tools.
+ * <br>
+ * For example, {@link java.util.Map#get(Object key)} should <em>not</em> be annotated {@link Nullable} because
+ * someone may have put not-null value in the map by this key and is expecting to find this value there ever since.
+ * <br>
+ * On the other hand, the {@link java.lang.ref.Reference#get()} should be annotated {@link Nullable} because
+ * it returns {@code null} if object got collected which can happen at any time completely unexpectedly.
+ */
+@Documented
+@Retention(RetentionPolicy.CLASS)
+@Target({ElementType.METHOD, ElementType.FIELD, ElementType.PARAMETER, ElementType.LOCAL_VARIABLE, ElementType.TYPE_USE})
+public @interface Nullable {
+    @NonNls String value() default "";
+}