Backport tests (#87)

* Fix unexpected number parse errors

* Add chapter titles

* Split test files by chapter

* Backport rename Fuzzer08Test to FuzzerWrap

* Replace graph build scripts with Makefile

* Backport Chapter05Test.testRegress1

* Backport require space after 'return'

* Backport check EOF after return statement

5 files changed, 387 insertions, 325 deletions

diff --git a/chapter05/src/test/java/com/seaofnodes/simple/Chapter01Test.java b/chapter05/src/test/java/com/seaofnodes/simple/Chapter01Test.java
new file mode 100644
index 00000000..547c36f8
--- /dev/null
+++ b/chapter05/src/test/java/com/seaofnodes/simple/Chapter01Test.java
@@ -0,0 +1,100 @@
+package com.seaofnodes.simple;
+
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.TypeInteger;
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+public class Chapter01Test {
+
+    @Test
+    public void testSimpleProgram() {
+        Parser parser = new Parser("return 1;");
+        StopNode stop = parser.parse();
+        StartNode start = Parser.START;
+        ReturnNode ret = (ReturnNode)stop.in(0);
+
+        assertTrue(ret.ctrl() instanceof ProjNode);
+        Node expr = ret.expr();
+        if( expr instanceof ConstantNode con ) {
+            assertEquals(start,con.in(0));
+            assertEquals(TypeInteger.constant(1), con._type);
+        } else {
+            fail();
+        }
+    }
+
+    @Test
+    public void testZero() {
+        Parser parser = new Parser("return 0;");
+        parser.parse();
+        StartNode start = Parser.START;
+        for( Node use : start._outputs )
+            if( use instanceof ConstantNode con )
+                assertEquals(TypeInteger.constant(0),con._type);
+    }
+
+    @Test
+    public void testBad1() {
+        try {
+            new Parser("ret").parse();
+            fail();
+        } catch( RuntimeException e ) {
+            assertEquals("Syntax error, expected =: ",e.getMessage());
+        }
+    }
+
+    @Test
+    public void testBad2() {
+        try {
+            new Parser("return 0123;").parse();
+            fail();
+        } catch( RuntimeException e ) {
+            assertEquals("Syntax error: integer values cannot start with '0'",e.getMessage());
+        }
+    }
+
+    @Test
+    public void testNotBad3() {
+        // this test used to fail in chapter 1
+        assertEquals("return 12;", new Parser("return --12;").parse().print());
+    }
+
+    @Test
+    public void testBad4() {
+        try {
+            new Parser("return 100").parse();
+            fail();
+        } catch( RuntimeException e ) {
+            assertEquals("Syntax error, expected ;: ",e.getMessage());
+        }
+    }
+
+    @Test
+    public void testNotBad5() {
+        // this test used to fail in chapter 1
+        assertEquals("return -100;", new Parser("return -100;").parse().print());
+    }
+
+    @Test
+    public void testBad6() {
+        try {
+            new Parser("return100").parse();
+            fail();
+        } catch( RuntimeException e ) {
+            assertEquals("Syntax error, expected =: ",e.getMessage());
+        }
+    }
+
+    @Test
+    public void testBad7() {
+        try {
+            new Parser("return 1;}").parse();
+            fail();
+        } catch( RuntimeException e ) {
+            assertEquals("Syntax error, unexpected }",e.getMessage());
+        }
+    }
+
+}
diff --git a/chapter05/src/test/java/com/seaofnodes/simple/Chapter02Test.java b/chapter05/src/test/java/com/seaofnodes/simple/Chapter02Test.java
new file mode 100644
index 00000000..4085ed7e
--- /dev/null
+++ b/chapter05/src/test/java/com/seaofnodes/simple/Chapter02Test.java
@@ -0,0 +1,66 @@
+package com.seaofnodes.simple;
+
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.TypeInteger;
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+public class Chapter02Test {
+
+    @Test
+    public void testParseGrammar() {
+        Parser parser = new Parser("return 1+2*3+-5;");
+        Node._disablePeephole = true; // disable peephole so we can observe full graph
+        StopNode ret = parser.parse();
+        assertEquals("return (1+((2*3)+(-5)));", ret.print());
+        GraphVisualizer gv = new GraphVisualizer();
+        System.out.println(gv.generateDotOutput(parser));
+        Node._disablePeephole = false;
+    }
+
+    @Test
+    public void testAddPeephole() {
+        Parser parser = new Parser("return 1+2;");
+        StopNode ret = parser.parse();
+        assertEquals("return 3;", ret.print());
+    }
+
+    @Test
+    public void testSubPeephole() {
+        Parser parser = new Parser("return 1-2;");
+        StopNode ret = parser.parse();
+        assertEquals("return -1;", ret.print());
+    }
+
+    @Test
+    public void testMulPeephole() {
+        Parser parser = new Parser("return 2*3;");
+        StopNode ret = parser.parse();
+        assertEquals("return 6;", ret.print());
+    }
+
+    @Test
+    public void testDivPeephole() {
+        Parser parser = new Parser("return 6/3;");
+        StopNode ret = parser.parse();
+        assertEquals("return 2;", ret.print());
+    }
+
+    @Test
+    public void testMinusPeephole() {
+        Parser parser = new Parser("return 6/-3;");
+        StopNode ret = parser.parse();
+        assertEquals("return -2;", ret.print());
+    }
+
+    @Test
+    public void testExample() {
+        Parser parser = new Parser("return 1+2*3+-5;");
+        StopNode ret = parser.parse();
+        assertEquals("return 2;", ret.print());
+        GraphVisualizer gv = new GraphVisualizer();
+        System.out.println(gv.generateDotOutput(parser));
+    }
+
+}
diff --git a/chapter05/src/test/java/com/seaofnodes/simple/Chapter03Test.java b/chapter05/src/test/java/com/seaofnodes/simple/Chapter03Test.java
new file mode 100644
index 00000000..407fbe48
--- /dev/null
+++ b/chapter05/src/test/java/com/seaofnodes/simple/Chapter03Test.java
@@ -0,0 +1,68 @@
+package com.seaofnodes.simple;
+
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.TypeInteger;
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+public class Chapter03Test {
+
+    @Test
+    public void testVarDecl() {
+        Parser parser = new Parser("int a=1; return a;");
+        StopNode ret = parser.parse();
+        assertEquals("return 1;", ret.print());
+    }
+
+    @Test
+    public void testVarAdd() {
+        Parser parser = new Parser("int a=1; int b=2; return a+b;");
+        StopNode ret = parser.parse();
+        assertEquals("return 3;", ret.print());
+    }
+
+    @Test
+    public void testVarScope() {
+        Parser parser = new Parser("int a=1; int b=2; int c=0; { int b=3; c=a+b; } return c;");
+        StopNode ret = parser.parse();
+        assertEquals("return 4;", ret.print());
+    }
+
+    @Test
+    public void testVarScopeNoPeephole() {
+        Parser parser = new Parser("int a=1; int b=2; int c=0; { int b=3; c=a+b; #showGraph; } return c; #showGraph;");
+        Node._disablePeephole = true;
+        StopNode ret = parser.parse();
+        Node._disablePeephole = false;
+        assertEquals("return (1+3);", ret.print());
+    }
+
+    @Test
+    public void testVarDist() {
+        Parser parser = new Parser("int x0=1; int y0=2; int x1=3; int y1=4; return (x0-x1)*(x0-x1) + (y0-y1)*(y0-y1); #showGraph;");
+        StopNode ret = parser.parse();
+        assertEquals("return 8;", ret.print());
+    }
+
+    @Test
+    public void testSelfAssign() {
+        try {
+            new Parser("int a=a; return a;").parse();
+            fail();
+        } catch( RuntimeException e ) {
+            assertEquals("Undefined name 'a'",e.getMessage());
+        }
+    }
+
+    @Test
+    public void testBad1() {
+        try {
+            new Parser("int a=1; int b=2; int c=0; { int b=3; c=a+b;").parse();
+            fail();
+        } catch( RuntimeException e ) {
+            assertEquals("Syntax error, expected }: ",e.getMessage());
+        }
+    }
+
+}
diff --git a/chapter05/src/test/java/com/seaofnodes/simple/Chapter04Test.java b/chapter05/src/test/java/com/seaofnodes/simple/Chapter04Test.java
new file mode 100644
index 00000000..cde23324
--- /dev/null
+++ b/chapter05/src/test/java/com/seaofnodes/simple/Chapter04Test.java
@@ -0,0 +1,128 @@
+package com.seaofnodes.simple;
+
+import com.seaofnodes.simple.node.*;
+import com.seaofnodes.simple.type.TypeInteger;
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+public class Chapter04Test {
+
+    @Test
+    public void testPeephole() {
+        Parser parser = new Parser("return 1+arg+2; #showGraph;");
+        StopNode ret = parser.parse();
+        assertEquals("return (arg+3);", ret.print());
+    }
+
+    @Test
+    public void testPeephole2() {
+        Parser parser = new Parser("return (1+arg)+2;");
+        StopNode ret = parser.parse();
+        assertEquals("return (arg+3);", ret.print());
+    }
+
+    @Test
+    public void testAdd0() {
+        Parser parser = new Parser("return 0+arg;");
+        StopNode ret = parser.parse();
+        assertEquals("return arg;", ret.print());
+    }
+
+    @Test
+    public void testAddAddMul() {
+        Parser parser = new Parser("return arg+0+arg;");
+        StopNode ret = parser.parse();
+        assertEquals("return (arg*2);", ret.print());
+    }
+
+    @Test
+    public void testPeephole3() {
+        Parser parser = new Parser("return 1+arg+2+arg+3; #showGraph;");
+        StopNode ret = parser.parse();
+        assertEquals("return ((arg*2)+6);", ret.print());
+    }
+
+    @Test
+    public void testMul1() {
+        Parser parser = new Parser("return 1*arg;");
+        StopNode ret = parser.parse();
+        assertEquals("return arg;", ret.print());
+    }
+
+    @Test
+    public void testVarArg() {
+        Parser parser = new Parser("return arg; #showGraph;");
+        StopNode stop = parser.parse();
+        ReturnNode ret = stop.ret();
+        assertTrue(ret.in(0) instanceof ProjNode);
+        assertTrue(ret.in(1) instanceof ProjNode);
+    }
+
+    @Test
+    public void testConstantArg() {
+        Parser parser = new Parser("return arg; #showGraph;", TypeInteger.constant(2));
+        StopNode ret = parser.parse();
+        assertEquals("return 2;", ret.print());
+    }
+
+    @Test
+    public void testCompEq() {
+        Parser parser = new Parser("return 3==3; #showGraph;");
+        StopNode ret = parser.parse();
+        assertEquals("return 1;", ret.print());
+    }
+
+    @Test
+    public void testCompEq2() {
+        Parser parser = new Parser("return 3==4; #showGraph;");
+        StopNode ret = parser.parse();
+        assertEquals("return 0;", ret.print());
+    }
+
+    @Test
+    public void testCompNEq() {
+        Parser parser = new Parser("return 3!=3; #showGraph;");
+        StopNode ret = parser.parse();
+        assertEquals("return 0;", ret.print());
+    }
+
+    @Test
+    public void testCompNEq2() {
+        Parser parser = new Parser("return 3!=4; #showGraph;");
+        StopNode ret = parser.parse();
+        assertEquals("return 1;", ret.print());
+    }
+
+    @Test
+    public void testBug1() {
+        Parser parser = new Parser("int a=arg+1; int b=a; b=1; return a+2; #showGraph;");
+        StopNode ret = parser.parse();
+        assertEquals("return (arg+3);", ret.print());
+    }
+
+    @Test
+    public void testBug2() {
+        Parser parser = new Parser("int a=arg+1; a=a; return a; #showGraph;");
+        StopNode ret = parser.parse();
+        assertEquals("return (arg+1);", ret.print());
+    }
+
+    @Test
+    public void testBug3() {
+        try {
+            new Parser("inta=1; return a;").parse();
+            fail();
+        } catch( RuntimeException e ) {
+            assertEquals("Undefined name 'inta'",e.getMessage());
+        }
+    }
+
+    @Test
+    public void testBug4() {
+        Parser parser = new Parser("return -arg;");
+        StopNode ret = parser.parse();
+        assertEquals("return (-arg);", ret.print());
+    }
+
+}
diff --git a/chapter05/src/test/java/com/seaofnodes/simple/Chapter05Test.java b/chapter05/src/test/java/com/seaofnodes/simple/Chapter05Test.java
index 97666d27..b5fcbeaf 100644
--- a/chapter05/src/test/java/com/seaofnodes/simple/Chapter05Test.java
+++ b/chapter05/src/test/java/com/seaofnodes/simple/Chapter05Test.java
@@ -2,16 +2,14 @@ package com.seaofnodes.simple;
 
 import com.seaofnodes.simple.node.*;
 import com.seaofnodes.simple.type.TypeInteger;
-import org.junit.Rule;
 import org.junit.Test;
-import org.junit.rules.ExpectedException;
 
 import static org.junit.Assert.*;
 
 public class Chapter05Test {
 
     @Test
-    public void testChapter5IfStmt() {
+    public void testIfStmt() {
         Parser parser = new Parser(
 """
 int a = 1;
@@ -28,7 +26,7 @@ return a;""");
     }
 
     @Test
-    public void testChapter5Test() {
+    public void testTest() {
         Parser parser = new Parser(
 """
 int c = 3;
@@ -43,7 +41,7 @@ return c;""", TypeInteger.BOT);
     }
 
     @Test
-    public void testChapter5Return2() {
+    public void testReturn2() {
         Parser parser = new Parser(
 """
 if( arg==1 )
@@ -56,7 +54,7 @@ else
     }
 
     @Test
-    public void testChapter5IfMergeB() {
+    public void testIfMergeB() {
         Parser parser = new Parser(
 """
 int a=arg+1;
@@ -71,7 +69,7 @@ return a+b;""");
     }
 
     @Test
-    public void testChapter5IfMerge2() {
+    public void testIfMerge2() {
         Parser parser = new Parser(
 """
 int a=arg+1;
@@ -86,7 +84,7 @@ return a+b;""");
     }
 
     @Test
-    public void testChapter5Merge3() {
+    public void testMerge3() {
         Parser parser = new Parser(
 """
 int a=1;
@@ -106,7 +104,7 @@ return a;
     }
 
     @Test
-    public void testChapter5Merge4() {
+    public void testMerge4() {
         Parser parser = new Parser(
 """
 int a=0;
@@ -122,7 +120,7 @@ return arg+a+b;
     }
 
     @Test
-    public void testChapter5Merge5() {
+    public void testMerge5() {
         Parser parser = new Parser(
 """
 int a=arg==2;
@@ -136,13 +134,13 @@ return a;""");
     }
 
     @Test
-    public void testChapter5True() {
+    public void testTrue() {
       StopNode stop = new Parser("return true;").parse();
       assertEquals("return 1;",stop.toString());
     }
 
     @Test
-    public void testChapter5HalfDef() {
+    public void testHalfDef() {
         try {
             new Parser("if( arg==1 ) int b=2; return b;").parse();
             fail();
@@ -152,7 +150,7 @@ return a;""");
     }
 
     @Test
-    public void testChapter5HalfDef2() {
+    public void testHalfDef2() {
         try {
             new Parser("if( arg==1 ) { int b=2; } else { int b=3; } return b;").parse();
             fail();
@@ -162,7 +160,17 @@ return a;""");
     }
 
     @Test
-    public void testChapter5BadNum() {
+    public void testRegress1() {
+        try {
+            new Parser("if(arg==2) int a=1; else int b=2; return a;").parse();
+            fail();
+        } catch( RuntimeException e ) {
+            assertEquals("Cannot define a new name on one arm of an if",e.getMessage());
+        }
+    }
+
+    @Test
+    public void testBadNum() {
         try {
             new Parser("return 1-;").parse();
             fail();
@@ -172,7 +180,7 @@ return a;""");
     }
 
     @Test
-    public void testChapter5Keyword1() {
+    public void testKeyword1() {
         try {
             new Parser("int true=0; return true;").parse();
             fail();
@@ -182,7 +190,7 @@ return a;""");
     }
 
     @Test
-    public void testChapter5Keyword2() {
+    public void testKeyword2() {
         try {
             new Parser("int else=arg; if(else) else=2; else else=1; return else;").parse();
             fail();
@@ -192,7 +200,7 @@ return a;""");
     }
 
     @Test
-        public void testChapter5Keyword3() {
+    public void testKeyword3() {
         try {
             new Parser("int a=1; ififif(arg)inta=2;return a;").parse();
             fail();
@@ -201,312 +209,4 @@ return a;""");
         }
     }
 
-    @Test
-    public void testChapter4Peephole() {
-        Parser parser = new Parser("return 1+arg+2; #showGraph;");
-        StopNode ret = parser.parse();
-        assertEquals("return (arg+3);", ret.print());
-    }
-
-    @Test
-    public void testChapter4Peephole2() {
-        Parser parser = new Parser("return (1+arg)+2;");
-        StopNode ret = parser.parse();
-        assertEquals("return (arg+3);", ret.print());
-    }
-
-    @Test
-    public void testChapter4Add0() {
-        Parser parser = new Parser("return 0+arg;");
-        StopNode ret = parser.parse();
-        assertEquals("return arg;", ret.print());
-    }
-
-    @Test
-    public void testChapter4AddAddMul() {
-        Parser parser = new Parser("return arg+0+arg;");
-        StopNode ret = parser.parse();
-        assertEquals("return (arg*2);", ret.print());
-    }
-
-    @Test
-    public void testChapter4Peephole3() {
-        Parser parser = new Parser("return 1+arg+2+arg+3; #showGraph;");
-        StopNode ret = parser.parse();
-        assertEquals("return ((arg*2)+6);", ret.print());
-    }
-
-    @Test
-    public void testChapter4Mul1() {
-        Parser parser = new Parser("return 1*arg;");
-        StopNode ret = parser.parse();
-        assertEquals("return arg;", ret.print());
-    }
-
-    @Test
-    public void testChapter4VarArg() {
-        Parser parser = new Parser("return arg; #showGraph;");
-        StopNode stop = parser.parse();
-        ReturnNode ret = stop.ret();
-        assertTrue(ret.in(0) instanceof ProjNode);
-        assertTrue(ret.in(1) instanceof ProjNode);
-    }
-
-    @Test
-    public void testChapter4ConstantArg() {
-        Parser parser = new Parser("return arg; #showGraph;", TypeInteger.constant(2));
-        StopNode ret = parser.parse();
-        assertEquals("return 2;", ret.print());
-    }
-
-    @Test
-    public void testChapter4CompEq() {
-        Parser parser = new Parser("return 3==3; #showGraph;");
-        StopNode ret = parser.parse();
-        assertEquals("return 1;", ret.print());
-    }
-
-    @Test
-    public void testChapter4CompEq2() {
-        Parser parser = new Parser("return 3==4; #showGraph;");
-        StopNode ret = parser.parse();
-        assertEquals("return 0;", ret.print());
-    }
-
-    @Test
-    public void testChapter4CompNEq() {
-        Parser parser = new Parser("return 3!=3; #showGraph;");
-        StopNode ret = parser.parse();
-        assertEquals("return 0;", ret.print());
-    }
-
-    @Test
-    public void testChapter4CompNEq2() {
-        Parser parser = new Parser("return 3!=4; #showGraph;");
-        StopNode ret = parser.parse();
-        assertEquals("return 1;", ret.print());
-    }
-
-    @Test
-    public void testChapter4Bug1() {
-        Parser parser = new Parser("int a=arg+1; int b=a; b=1; return a+2; #showGraph;");
-        StopNode ret = parser.parse();
-        assertEquals("return (arg+3);", ret.print());
-    }
-
-    @Test
-    public void testChapter4Bug2() {
-        Parser parser = new Parser("int a=arg+1; a=a; return a; #showGraph;");
-        StopNode ret = parser.parse();
-        assertEquals("return (arg+1);", ret.print());
-    }
-
-    @Test
-    public void testChapter4Bug3() {
-        try {
-            new Parser("inta=1; return a;").parse();
-            fail();
-        } catch( RuntimeException e ) {
-            assertEquals("Undefined name 'inta'",e.getMessage());
-        }
-    }
-
-    @Test
-    public void testChapter4Bug4() {
-        Parser parser = new Parser("return -arg;");
-        StopNode ret = parser.parse();
-        assertEquals("return (-arg);", ret.print());
-    }
-
-    @Test
-    public void testVarDecl() {
-        Parser parser = new Parser("int a=1; return a;");
-        StopNode ret = parser.parse();
-        assertEquals("return 1;", ret.print());
-    }
-
-    @Test
-    public void testVarAdd() {
-        Parser parser = new Parser("int a=1; int b=2; return a+b;");
-        StopNode ret = parser.parse();
-        assertEquals("return 3;", ret.print());
-    }
-
-    @Test
-    public void testVarScope() {
-        Parser parser = new Parser("int a=1; int b=2; int c=0; { int b=3; c=a+b; } return c;");
-        StopNode ret = parser.parse();
-        assertEquals("return 4;", ret.print());
-    }
-
-    @Test
-    public void testVarScopeNoPeephole() {
-        Parser parser = new Parser("int a=1; int b=2; int c=0; { int b=3; c=a+b; #showGraph; } return c; #showGraph;");
-        Node._disablePeephole = true;
-        StopNode ret = parser.parse();
-        Node._disablePeephole = false;
-        assertEquals("return (1+3);", ret.print());
-    }
-
-    @Test
-    public void testVarDist() {
-        Parser parser = new Parser("int x0=1; int y0=2; int x1=3; int y1=4; return (x0-x1)*(x0-x1) + (y0-y1)*(y0-y1); #showGraph;");
-        StopNode ret = parser.parse();
-        assertEquals("return 8;", ret.print());
-    }
-
-    @Test
-    public void testSelfAssign() {
-        try {
-            new Parser("int a=a; return a;").parse();
-            fail();
-        } catch( RuntimeException e ) {
-            assertEquals("Undefined name 'a'",e.getMessage());
-        }
-    }
-
-    @Test
-    public void testChapter2ParseGrammar() {
-        Parser parser = new Parser("return 1+2*3+-5;");
-        Node._disablePeephole = true; // disable peephole so we can observe full graph
-        StopNode ret = parser.parse();
-        assertEquals("return (1+((2*3)+(-5)));", ret.print());
-        GraphVisualizer gv = new GraphVisualizer();
-        System.out.println(gv.generateDotOutput(parser));
-        Node._disablePeephole = false;
-    }
-
-    @Test
-    public void testChapter2AddPeephole() {
-        Parser parser = new Parser("return 1+2;");
-        StopNode ret = parser.parse();
-        assertEquals("return 3;", ret.print());
-    }
-
-    @Test
-    public void testChapter2SubPeephole() {
-        Parser parser = new Parser("return 1-2;");
-        StopNode ret = parser.parse();
-        assertEquals("return -1;", ret.print());
-    }
-
-    @Test
-    public void testChapter2MulPeephole() {
-        Parser parser = new Parser("return 2*3;");
-        StopNode ret = parser.parse();
-        assertEquals("return 6;", ret.print());
-    }
-
-    @Test
-    public void testChapter2DivPeephole() {
-        Parser parser = new Parser("return 6/3;");
-        StopNode ret = parser.parse();
-        assertEquals("return 2;", ret.print());
-    }
-
-    @Test
-    public void testChapter2MinusPeephole() {
-        Parser parser = new Parser("return 6/-3;");
-        StopNode ret = parser.parse();
-        assertEquals("return -2;", ret.print());
-    }
-
-    @Test
-    public void testChapter2Example() {
-        Parser parser = new Parser("return 1+2*3+-5;");
-        StopNode ret = parser.parse();
-        assertEquals("return 2;", ret.print());
-        GraphVisualizer gv = new GraphVisualizer();
-        System.out.println(gv.generateDotOutput(parser));
-    }
-
-    @Test
-    public void testSimpleProgram() {
-        Parser parser = new Parser("return 1;");
-        StopNode stop = parser.parse();
-        StartNode start = Parser.START;
-        ReturnNode ret = (ReturnNode)stop.in(0);
-
-        assertTrue(ret.ctrl() instanceof ProjNode);
-        Node expr = ret.expr();
-        if( expr instanceof ConstantNode con ) {
-            assertEquals(start,con.in(0));
-            assertEquals(TypeInteger.constant(1), con._type);
-        } else {
-            fail();
-        }
-    }
-
-    @Test
-    public void testZero() {
-        Parser parser = new Parser("return 0;");
-        parser.parse();
-        StartNode start = Parser.START;
-        for( Node use : start._outputs )
-            if( use instanceof ConstantNode con )
-                assertEquals(TypeInteger.constant(0),con._type);
-    }
-
-    @Test
-    public void testBad1() {
-        try {
-            new Parser("ret").parse();
-            fail();
-        } catch( RuntimeException e ) {
-            assertEquals("Syntax error, expected =: ",e.getMessage());
-        }
-    }
-
-    @Test
-    public void testBad2() {
-        try {
-            new Parser("return 0123;").parse();
-            fail();
-        } catch( RuntimeException e ) {
-            assertEquals("Syntax error: integer values cannot start with '0'",e.getMessage());
-        }
-    }
-
-    @Test
-    public void testNotBad3() {
-        // this test used to fail in chapter 1
-        assertEquals("return 12;", new Parser("return --12;").parse().print());
-    }
-
-    @Test
-    public void testBad4() {
-        try {
-            new Parser("return 100").parse();
-            fail();
-        } catch( RuntimeException e ) {
-            assertEquals("Syntax error, expected ;: ",e.getMessage());
-        }
-    }
-
-    @Test
-    public void testNotBad5() {
-        // this test used to fail in chapter 1
-        assertEquals("return -100;", new Parser("return -100;").parse().print());
-    }
-
-    @Test
-    public void testBad6() {
-        try {
-            new Parser("int a=1; int b=2; int c=0; { int b=3; c=a+b;").parse();
-            fail();
-        } catch( RuntimeException e ) {
-            assertEquals("Syntax error, expected }: ",e.getMessage());
-        }
-    }
-
-    @Test
-    public void testBad7() {
-        try {
-            new Parser("return 1;}").parse();
-            fail();
-        } catch( RuntimeException e ) {
-            assertEquals("Syntax error, unexpected }",e.getMessage());
-        }
-    }
-
 }