diff options
Diffstat (limited to 'chapter15')
| -rw-r--r-- | chapter15/src/main/java/com/seaofnodes/simple/node/SubNode.java | 10 | ||||
| -rw-r--r-- | chapter15/src/test/java/com/seaofnodes/simple/Chapter12Test.java | 7 |
2 files changed, 12 insertions, 5 deletions
diff --git a/chapter15/src/main/java/com/seaofnodes/simple/node/SubNode.java b/chapter15/src/main/java/com/seaofnodes/simple/node/SubNode.java index a433ca90..237e40ed 100644 --- a/chapter15/src/main/java/com/seaofnodes/simple/node/SubNode.java +++ b/chapter15/src/main/java/com/seaofnodes/simple/node/SubNode.java @@ -42,11 +42,11 @@ public class SubNode extends Node { Type t1 = lhs._type; Type t2 = rhs._type; - if( t2.isConstant() && t2 instanceof TypeInteger i && i.value()==0 ) - return lhs; - - if( t1.isConstant() && t1 instanceof TypeInteger i && i.value()==0 ) - return new MinusNode(rhs); + // Keep invalid operands for type checking. + if( t1 instanceof TypeInteger x && t2 instanceof TypeInteger y ) { + if( y.isConstant() && y.value()==0 ) return lhs; + if( x.isConstant() && x.value()==0 ) return new MinusNode(rhs); + } // x - (-y) is x+y if( rhs instanceof MinusNode minus ) diff --git a/chapter15/src/test/java/com/seaofnodes/simple/Chapter12Test.java b/chapter15/src/test/java/com/seaofnodes/simple/Chapter12Test.java index c8802f4c..4eaf81df 100644 --- a/chapter15/src/test/java/com/seaofnodes/simple/Chapter12Test.java +++ b/chapter15/src/test/java/com/seaofnodes/simple/Chapter12Test.java @@ -8,6 +8,13 @@ import static org.junit.Assert.assertEquals; import static org.junit.Assert.fail; public class Chapter12Test { + @Test public void testSubZeroFloat() { + var stop = new Parser("flt x = arg; return 0-x;").parse().iterate(); + // Compare strings so +0.0 and -0.0 remain distinct. + assertEquals("0.0", Evaluator.evaluate(stop,0).toString()); + assertEquals("-1.0", Evaluator.evaluate(stop,1).toString()); + } + @Test public void testDeadNumericReturns() { for( String[] test : new String[][] { {"if(1) return 7; else return 2.5;", "7"}, |