diff options
Diffstat (limited to 'test')
-rw-r--r-- | test/junit/scala/tools/nsc/backend/jvm/analysis/NullnessAnalyzerTest.scala | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/test/junit/scala/tools/nsc/backend/jvm/analysis/NullnessAnalyzerTest.scala b/test/junit/scala/tools/nsc/backend/jvm/analysis/NullnessAnalyzerTest.scala index 3d5343e395..3a85f03da2 100644 --- a/test/junit/scala/tools/nsc/backend/jvm/analysis/NullnessAnalyzerTest.scala +++ b/test/junit/scala/tools/nsc/backend/jvm/analysis/NullnessAnalyzerTest.scala @@ -202,4 +202,30 @@ class NullnessAnalyzerTest extends ClearAfterClass { (end, 5, Null) // d, no change )) testNullness(a, m, insn, index, nullness) } + + @Test + def testInstanceOf(): Unit = { + val code = + """def f(a: Object) = { + | val x = a + | x.isInstanceOf[Throwable] // x and a remain unknown - INSTANCEOF doesn't throw a NPE on null + | x.toString // x and a are not null + | a.asInstanceOf[String].trim // the stack value (LOAD of local a) is still not-null after the CHECKCAST + |} + """.stripMargin + val List(m) = compileMethods(noOptCompiler)(code) + val a = newNullnessAnalyzer(m) + + val instof = "+INSTANCEOF" + val tost = "+INVOKEVIRTUAL java/lang/Object.toString" + val trim = "INVOKEVIRTUAL java/lang/String.trim" + + for ((insn, index, nullness) <- List( + (instof, 1, Unknown), // a after INSTANCEOF + (instof, 2, Unknown), // x after INSTANCEOF + (tost, 1, NotNull), + (tost, 2, NotNull), + (trim, 3, NotNull) // receiver at `trim` + )) testNullness(a, m, insn, index, nullness) + } } |