Check for compile-time constants in DartCompiler

compiler/javatests/com/google/dart/compiler/resolver/CompileTimeConstantTest.java

+// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+package com.google.dart.compiler.resolver;
+
+import com.google.common.base.Joiner;
+import com.google.dart.compiler.DartCompilerErrorCode;
+
+/**
+ * Tests the code in {@link CompileTimeConstantVisitor}
+ */
+public class CompileTimeConstantTest extends ResolverTestCase {
+
+  public void testConstantBinaryExpression() {
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class A {",
+        " static final INT_LIT = 5;",
+        " static final INT_LIT_REF = INT_LIT;",
+        " static final DOUBLE_LIT = 1.5;",
+        " static final BOOL_LIT = true;",
+        " static final STRING_LIT = \"Hello\";",
+        " static final BOP1_0 = INT_LIT + 1;",
+        " static final BOP1_1 = 1 + INT_LIT;",
+        " static final BOP1_2 = INT_LIT - 1;",
+        " static final BOP1_3 = 1 - INT_LIT;",
+        " static final BOP1_4 = INT_LIT * 1;",
+        " static final BOP1_5 = 1 * INT_LIT;",
+        " static final BOP1_6 = INT_LIT / 1;",
+        " static final BOP1_7 = 1 / INT_LIT;",
+        " static final BOP2_0 = DOUBLE_LIT + 1.5;",
+        " static final BOP2_1 = 1.5 + DOUBLE_LIT;",
+        " static final BOP2_2 = DOUBLE_LIT - 1.5;",
+        " static final BOP2_3 = 1.5 - DOUBLE_LIT;",
+        " static final BOP2_4 = DOUBLE_LIT * 1.5;",
+        " static final BOP2_5 = 1.5 * DOUBLE_LIT;",
+        " static final BOP2_6 = DOUBLE_LIT / 1.5;",
+        " static final BOP2_7 = 1.5 / DOUBLE_LIT;",
+        " static final BOP3_0 = 2 < INT_LIT;",
+        " static final BOP3_1 = INT_LIT < 2;",
+        " static final BOP3_2 = 2 > INT_LIT;",
+        " static final BOP3_3 = INT_LIT > 2;",
+        " static final BOP3_4 = 2 < DOUBLE_LIT;",
+        " static final BOP3_5 = DOUBLE_LIT < 2;",
+        " static final BOP3_6 = 2 > DOUBLE_LIT;",
+        " static final BOP3_7 = DOUBLE_LIT > 2;",
+        " static final BOP3_8 = 2 <= INT_LIT;",
+        " static final BOP3_9 = INT_LIT <= 2;",
+        " static final BOP3_10 = 2 >= INT_LIT;",
+        " static final BOP3_11 = INT_LIT >= 2;",
+        " static final BOP3_12 = 2.0 <= DOUBLE_LIT;",
+        " static final BOP3_13 = DOUBLE_LIT <= 2.0;",
+        " static final BOP3_14 = 2.0 >= DOUBLE_LIT;",
+        " static final BOP3_15 = DOUBLE_LIT >= 2;",
+        " static final BOP4_0 = 5 % INT_LIT;",
+        " static final BOP4_1 = INT_LIT % 5;",
+        " static final BOP4_2 = 5.0 % DOUBLE_LIT;",
+        " static final BOP4_3 = DOUBLE_LIT % 5.0;",
+        " static final BOP5_0 = 0x80 & 0x04;",
+        " static final BOP5_1 = 0x80 | 0x04;",
+        " static final BOP5_2 = 0x80 << 0x04;",
+        " static final BOP5_3 = 0x80 >> 0x04;",
+        " static final BOP5_4 = 0x80 ~/ 0x04;",
+        " static final BOP5_5 = 0x80 ^ 0x04;",
+        " static final BOP6 = BOOL_LIT && true;",
+        " static final BOP7 = false || BOOL_LIT;",
+        " static final BOP8 = STRING_LIT == \"World!\";",
+        " static final BOP9 = \"Hello\" != STRING_LIT;",
+        " static final BOP10 = INT_LIT === INT_LIT_REF;",
+        " static final BOP11 = BOOL_LIT !== true;",
+        "}"));
+
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class int {}",
+        "class A {",
+        " static int foo() { return 1; }",
+        "}",
+        "class B {",
+        " static final BOP1 = A.foo() * 1;",
+        " static final BOP2 = 1 * A.foo();",
+        "}"),
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,

[ngeoffray, 2011/10/14 09:26:56]

It looks like the error messages are duplicated, right? Maybe we should just
have one?

[zundel, 2011/10/14 10:04:21]

What's happening is that first, A.foo() isn't a const expression when we analyze
that node.  Second, when analyzing the binary expression, the LHS has type
dynamic becuase A.foo()'s return type can't be determined (type analysis hasn't
run yet.).  I am not sure how to get rid of one of these errors in this case
without squelching a legitmate error case.

[ngeoffray, 2011/10/14 10:33:42]

I understand why you're getting both errors, according to the analysis flow. But
I hope that the user only sees one error message. In general, two error messages
on the same expression somehow confuses me. I don't know what's best for
everyone. Feel free to ignore if you think it's ok.

+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER);
+
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class int {}",
+        "class String {}",
+        "class A {",
+        " static int foo() { return 1; }",
+        " static String bar() { return \"1\"; }",
+        "}",
+        "class B {",
+        " static final BOP1 = 2 < A.foo();",
+        " static final BOP2 = A.foo() < 2;",
+        " static final BOP3 = 2 < A.bar();",
+        " static final BOP4 = A.bar() < 2;",
+        "}"),
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER);
+
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class bool {}",
+        "class int {}",
+        "class double {}",
+        "class num {}",
+        "class A {",
+        " static bool foo() { return true; }",
+        "}",
+        "class B {",
+        " static final BOP1 = 0x80 & 2.0;",
+        " static final BOP2 = 2.0 & 0x80;",
+        " static final BOP3 = 45 && true;",
+        " static final BOP4 = true || 45;",
+        " static final BOP5 = true && A.foo();",
+        " static final BOP6 = A.foo() && false;",
+        "}"),
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_INT,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_INT,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_BOOLEAN,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_BOOLEAN,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_BOOLEAN,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_BOOLEAN);
+
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class bool {}",
+        "class int {}",
+        "class double {}",
+        "class num {}",
+        "class A {",
+        " static Object foo() { return true; }",
+        "}",
+        "class B {",
+        " const B();",
+        " static final OBJECT_LIT = new B();",
+        " static final INT_LIT = 1;",
+        " static final STRING_LIT = \"true\";",
+        " static final BOP1 = STRING_LIT && true;",
+        " static final BOP2 = false || STRING_LIT;",
+        " static final BOP3 = 59 == OBJECT_LIT;",
+        " static final BOP4 = OBJECT_LIT != 59;",
+        " static final BOP5 = INT_LIT === OBJECT_LIT;",
+        " static final BOP6 = OBJECT_LIT !== true;",
+        "}"),
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_BOOLEAN,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_BOOLEAN,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_STRING_NUMBER_BOOL,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_STRING_NUMBER_BOOL,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_STRING_NUMBER_BOOL,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_STRING_NUMBER_BOOL);
+
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class A {",
+        "  static final INT_LIT = 5;",
+        "  static final INT_LIT_REF = INT_LIT;",
+        "  static final DOUBLE_LIT = 1.5;",
+        "  static final BOOL_LIT = true;",
+        "  // Multiple binary expresions",
+        "  static final BOP1 = 1 * INT_LIT / 3 + INT_LIT + 9;",
+        "  // Parenthized expression",
+        "  static final BOP2 = ( 1 > 2 );",
+        "  static final BOP3 = (1 * 2) + 3;",
+        "  static final BOP4 = 3 + (1 * 2);",
+        "}"));
+
+    // Negative Tests
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class A {",
+        "  static final INT_LIT = 5;",
+        "  static final DOUBLE_LIT = 1.5;",
+        "  const A();",
+        "  static final OBJECT_LIT = new A();",
+        "  // Multiple binary expresions",
+        "  static final BOP1_0 = 0 + 1 + OBJECT_LIT;",
+        "  static final BOP1_1 = 0 + OBJECT_LIT + 1;",
+        "  static final BOP1_2 = OBJECT_LIT + 3 + 9;",
+        "}"),
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER);
+
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class A {",
+        "  static final INT_LIT = 5;",
+        "  static final DOUBLE_LIT = 1.5;",
+        "  const A();",
+        "  static final OBJECT_LIT = new A();",
+        "  // Multiple binary expresions",
+        "  static final PP0 = 0 - (1 + OBJECT_LIT);",
+        "  static final PP1 = 0 + (OBJECT_LIT + 1);",
+        "  static final PP2 = (OBJECT_LIT + 3) + 9;",
+        "  static final PP3 = (OBJECT_LIT) + 3 + 9;",
+        "  static final PP4 = (OBJECT_LIT + 3 + 9);",
+        "  static final PP5 = OBJECT_LIT + (3 + 9);",
+        "}"),
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_NUMBER);
+  }
+
+  public void testConstantUnaryExpression() {
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class A {",
+        "  // Unary expression",
+        "  static final BOOL_LIT = true;",
+        "  static final INT_LIT = 123;",
+        "  static final DOUBLE_LIT = 12.3;",
+        "  static final UOP1_0 = !BOOL_LIT;",
+        "  static final UOP1_1 = BOOL_LIT || !true;",
+        "  static final UOP1_2 = !BOOL_LIT || true;",
+        "  static final UOP1_3 = !(BOOL_LIT && true);",
+        "  static final UOP2_0 = ~0xf0;",
+        "  static final UOP2_1 = ~INT_LIT;",
+        "  static final UOP2_2 = ~INT_LIT & 123;",
+        "  static final UOP2_3 = ~(INT_LIT | 0xff);",
+        "  static final UOP3_0 = -0xf0;",
+        "  static final UOP3_1 = -INT_LIT;",
+        "  static final UOP3_2 = -INT_LIT + 123;",
+        "  static final UOP3_3 = -(INT_LIT * 0xff);",
+        "  static final UOP3_4 = -0xf0;",
+        "  static final UOP3_5 = -DOUBLE_LIT;",
+        "  static final UOP3_6 = -DOUBLE_LIT + 123;",
+        "  static final UOP3_7 = -(DOUBLE_LIT * 0xff);",
+        "}"));
+
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class int {}",
+        "class A {",
+        "  // Unary expression",
+        "  static final BOOL_LIT = true;",
+        "  static int foo() { return 3; }",
+        "  static final UOP1 = !5;",
+        "  static final UOP2 = !foo();",
+        "  static final UOP3 = !(5);",
+        "  static final UOP4 = !(foo());",
+        "}"),
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_BOOLEAN,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_BOOLEAN,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_BOOLEAN,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION,
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION_BOOLEAN);
+  }
+
+  public void testConstantConstructorAssign() {
+
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class A {",
+        "  const A();",
+        "  static final a = new A();", // Constant constructor
+        "}"));
+
+    // Negative tests
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class A {",
+        "  A() {}",
+        " static final a = new A();", // Error: not a constant constructor
+        "}"),
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION);
+  }
+
+  public void testConstantLiteralAssign() {
+
+    resolveAndTest(Joiner.on("\n").join(
+                                        "class Object {}",
+                                        "class A {",
+        "  static final b = true;",
+        "  static final s = \"apple\";", // string literal
+        "  static final i = 1;", // integer literal
+        "  static final d = 3.3;", // double literal
+        "  static final h = 0xf;", // hex literal
+        "  static final n = null;", // null
+        "}"));
+
+    // Tegative tests
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class A {",
+        "  static final person = \"earthling\";",
+        "  static final s = \"Hello ${person}!\";",
+        "}"),
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION);
+  }
+
+  public void testConstantTypedLiteralAssign() {
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class List<T> {}",
+        "class Map<K,V> {}",
+        "class A {",
+        "  static final aList = const[1, 2, 3];", // array literal
+        "  static final map = const { \"1\": \"one\", \"2\": \"banana\" };", // map literal
+        "}"));
+
+    // Negative tests, on literals that are not compile time constants.
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class List<T> {}",
+        "class A {",
+        "  // array literal not const",
+        "  static final aList= [1, 2, 3];",
+        "}"),
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION);
+
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class List<T> {}",
+        "class A {",
+        "  static foo() { return 1; }",
+        "  // const array literal contains non-const member",
+        "  static final aList = const [foo(), 2, 3];",
+        "}"),
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION);
+
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class Map<K,V> {}",
+        "class A {",
+        "  // map literal is not const",
+        "  static final aMap = { \"1\": \"one\", \"2\": \"banana\" };",
+        "}"),
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION);
+
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class String {}",
+        "class Map<K,V> {}",
+        "class A {",
+        "  static String foo() { return \"one\"; }",
+        "  // map literal contains non-const member",
+        "  static final map = const { \"1\":foo(), \"2\": \"banana\" };",
+        "}"),
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION);
+  }
+
+  public void testConstantVariableAssign() {
+    resolveAndTest(Joiner.on("\n").join(
+                                        "class Object {}",
+        "class A {",
+        "  static final i = 1;",
+        "  static final j = i;", // variable that is a compile-time constant
+        "}"));
+
+    // Negative tests
+    resolveAndTest(Joiner.on("\n").join(
+        "class Object {}",
+        "class A {",
+        " static foo() {return 1;}",
+        " static final i = foo();",  // Error: not a constant integer
+        "}"),
+        DartCompilerErrorCode.EXPECTED_CONSTANT_EXPRESSION);
+  }
+}