IDEA-209947 Explain boolean result from trivial contract

GitOrigin-RevId: 78eef614c45e43e307f8986c79005f2ca6a1fe01

java/java-tests/testData/inspection/dataFlow/tracker/ArrayLengthCollectionSize.java

@@ -3,7 +3,7 @@ Value is always false (s.length == list.size(); line#15)
   Left operand is >= 1 (s.length; line#15)
     Range is known from line #12 (s[0]; line#12)
   and right operand is 0 (list.size(); line#15)
-    Range is known from line #13 (list.isEmpty(); line#13)
+    Range is known from line #13 (!list.isEmpty(); line#13)
  */
 import java.util.List;
 

java/java-tests/testData/inspection/dataFlow/tracker/InstanceOfSecondCheck.java

@@ -0,0 +1,19 @@
+/*
+Value is always true (!isString; line#13)
+  Value 'isString' is always 'false' (isString; line#13)
+    'isString == false' was established from condition (isString; line#10)
+ */
+
+public class ExplainMe {
+  public int foo(Object a) {
+    boolean isString = a instanceof String;
+    if (isString) {
+      return 0;
+    }
+    if (<selection>!isString</selection>) {
+      return 1;
+    }
+    return 0;
+
+  }
+}

java/java-tests/testData/inspection/dataFlow/tracker/ListAddContract.java

@@ -0,0 +1,12 @@
+/*
+Value is always true (list.add("foo"); line#9)
+  According to contract, method 'add' always returns 'true' value (add; line#9)
+ */
+
+import java.util.List;
+
+class Test {
+  void test(List<String> list) {
+    if(<selection>list.add("foo")</selection>) {}
+  }
+}

java/java-tests/testData/inspection/dataFlow/tracker/NullCheckNpeNullCheck.java

@@ -0,0 +1,22 @@
+/*
+Value is always true (map != null; line#18)
+  'map' was dereferenced (map; line#14)
+ */
+
+import java.util.Map;
+
+public class ExplainMe {
+  void checkTheMap(Map<String, Integer> map) {
+    if (map == null) {
+      System.out.println("that's null");
+    }
+
+    if (map.get("ONE") == null) {
+      System.out.println("Okay");
+    }
+
+    if (<selection>map != null</selection>) {
+      System.out.println("not null");
+    }
+  }
+}

java/java-tests/testData/inspection/dataFlow/tracker/RepeatingIntegerComparisonThreeBranches.java

@@ -1,12 +1,12 @@
 /*
 Value is always true (x < y; line#13)
-  Condition 'x < y' was checked before (x > y; line#7)
+  Condition 'x < y' was checked before (x == y; line#9)
  */
 class Test {
   void test(int x, int y) {
-    if (x > y) return;
+    if (x > y) return; // would be better to point also here, but acceptable
 
-    if (x == y) { // explanation doesn't point here: not entirely correct, but hard to fix; postponed
+    if (x == y) {
       return;
     }
 

java/java-tests/testData/inspection/dataFlow/tracker/TripleCheck.java

@@ -0,0 +1,15 @@
+/*
+Value is always false (x; line#12)
+  'x == false' was established from condition (x; line#9)
+ */
+
+class Test {
+  void test(boolean x) {
+    if(x) {}
+    if(x) {
+      
+    } else {
+      if(<selection>x</selection>) {}
+    }
+  }
+}