Implement ES6 completion semantics (--harmony-completion).

test/mjsunit/harmony/completion.js

+// Copyright 2015 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --harmony-completion --harmony-sloppy-let --no-legacy-const
+
+
+function assertUndef(x) {
+  assertEquals(undefined, x);
+}
+
+
+// IfStatement [13.6.7]
+
+assertUndef(eval('42; if (true) ; else 0;'));  // ES5: 42
+assertUndef(eval('42; if (true) ;'));  // ES5: 42
+assertUndef(eval('42; if (false) 0;'));  // ES5: 42
+
+assertEquals(1, eval('42; if (true) 1;'));
+assertEquals(1, eval('42; if (true) 1; else 0;'));
+assertEquals(0, eval('42; if (false) 1; else 0;'));
+
+
+// IterationStatement [13.7]
+
+assertUndef(eval('42; do ; while (false);'));  // ES5: 42
+assertUndef(eval('42; var x = 1; do ; while (x--);'));  // ES5: 42
+assertUndef(eval('42; while (false) 0;'));  // ES5: 42
+assertUndef(eval('42; while (true) break;'));  // ES5: 42
+assertUndef(eval('42; bla: while (true) break bla;'));  // ES5: 42
+assertUndef(eval('42; var x = 1; while (x--) ;'));  // ES5: 42
+assertUndef(eval('42; for (; false; ) 0;'));  // ES5: 42
+assertUndef(eval('42; for (var x = 1; x; x--) ;'));  // ES5: 42
+assertUndef(eval('42; for (var x in ["foo", "bar"]) ;'));
+assertUndef(eval('42; for (var x of ["foo", "bar"]) ;'));
+assertUndef(eval('42; for (let x = 1; x; x--) ;'));
+assertUndef(eval('42; for (let x in ["foo", "bar"]) ;'));
+assertUndef(eval('42; for (let x of ["foo", "bar"]) ;'));
+assertUndef(eval('42; for (const x in ["foo", "bar"]) ;'));
+assertUndef(eval('42; for (const x of ["foo", "bar"]) ;'));
+
+assertEquals(1, eval('42; var x = 10; do x--; while (x);'));
+assertEquals(1, eval('42; var x = 10; while (x) x--;'));
+assertEquals(1, eval('42; for (var x = 10; x; x--) x;'));
+assertEquals(1, eval('42; for (var x = 10; x; --x) x;'));
+assertEquals(1, eval('42; for (let x = 10; x; --x) x;'));
+assertEquals(1, eval('42; var y = 2; for (var x in ["foo", "bar"]) y--;'));
+assertEquals(1, eval('42; var y = 2; for (const x in ["foo", "bar"]) y--;'));
+assertEquals(1, eval('42; var y = 2; for (let x in ["foo", "bar"]) y--;'));
+assertEquals(1, eval('42; var y = 2; for (var x of ["foo", "bar"]) y--;'));
+assertEquals(1, eval('42; var y = 2; for (const x of ["foo", "bar"]) y--;'));
+assertEquals(1, eval('42; var y = 2; for (let x of ["foo", "bar"]) y--;'));
+
+
+// WithStatement [13.11.7]
+
+assertUndef(eval('42; with ({}) ;'));  // ES5: 42
+
+assertEquals(1, eval('42; with ({}) 1;'));
+
+
+// SwitchStatement [13.12.11]
+
+assertUndef(eval('42; switch (0) {};'));  // ES5: 42
+assertUndef(eval('42; switch (0) { case 1: 1; };'));  // ES5: 42
+assertUndef(eval('42; switch (0) { case 0: ; };'));  // ES5: 42
+assertUndef(eval('42; switch (0) { default: ; };'));  // ES5: 42
+assertUndef(eval('42; switch (0) { case 0: break; }'));  // ES5: 42
+
+assertEquals(1, eval('42; switch (0) { case 0: 1; }'));
+assertEquals(1, eval('42; switch (0) { case 0: 1; break; }'));
+assertEquals(1, eval('42; switch (0) { case 0: 1; case 666: break; }'));
+assertEquals(2, eval('42; switch (0) { case 0: 1; case 666: 2; break; }'));
+
+
+// TryStatement [13.15.8]
+
+assertUndef(eval('42; try { } catch(e) { };'));  // ES5: 42
+assertUndef(eval('42; try { } catch(e) { 0; };'));  // ES5: 42
+assertUndef(eval('42; try { throw "" } catch(e) { };'));  // ES5: 42
+assertUndef(eval('42; try { throw "" } catch(e) { } finally { };'));  // ES5: 42
+assertUndef(eval('42; try { } finally { 666 };'));  // ES5: 42
+
+
+// Some combinations
+
+assertUndef(eval('42; switch (0) { case 0: if (true) break; }'));  // ES5: 42
+assertUndef(eval('42; switch (0) { case 0: 1; if (true) ; }'));  // ES5: 1
+assertUndef(eval('42; switch (0) { case 0: 1; try { break } catch(e) { }; }'));  // ES5: 1
+
+assertEquals(0, eval('42; switch (0) { case 0: 0; case 1: break; }'));
+assertEquals(0, eval('42; while (1) { 0; break; }'))
+assertEquals(0, eval('42; bla: while (1) { 0; break bla; }'))
+assertEquals(0, eval('42; while (1) { with ({}) { 0; break; } }'))
+assertEquals(0, eval('42; while (1) { try { 0; break } catch(e) {666} }'))
+assertEquals(0, eval(
+    '42; while (1) { try { 0; break } catch(e) {666} finally {666} }'))
+assertEquals(0, eval(
+    '42; while (1) { try { throw "" } catch(e) {666} finally {0; break} }'))
+assertEquals(0, eval(
+    '42; while (1) { try { throw "" } catch(e) {0; break} finally {666} }'))
+assertEquals(0, eval(
+    '42; while (1) { try { 666 } finally {0; break} }'));
+assertEquals(0, eval(
+    '42; while (1) { try { 666; break } finally {0; break} }'));
+assertEquals(0, eval(
+    '42; lab: try { 666; break lab } finally {0; break lab}'));
+assertEquals(undefined, eval(
+  'var b = 1; ' +
+  'outer: while (1) { while (1) { if (b--) 42; else break outer; }; 666 }'));
+
+// The following is not what ES6 says, but see ES bug 4540.
+assertUndef(eval('42; switch (0) { case 0: 1; if (true) break; }'));  // ES5: 1
+
+
+
+////////////////////////////////////////////////////////////////////////////////
+//
+// The following are copied from webkit/eval-throw-return and adapted.
+
+function throwFunc() {
+  throw "";
+}
+
+function throwOnReturn(){
+  1;
+  return throwFunc();
+}
+
+function twoFunc() {
+  2;
+}
+
+assertEquals(1, eval("1;"));
+assertUndef(eval("1; try { foo = [2,3,throwFunc(), 4]; } catch (e){}"));
+assertUndef(eval("1; try { 2; throw ''; } catch (e){}"));
+assertUndef(eval("1; try { 2; throwFunc(); } catch (e){}"));
+assertEquals(3, eval("1; try { 2; throwFunc(); } catch (e){3;} finally {}"));
+assertEquals(3, eval("1; try { 2; throwFunc(); } catch (e){3;} finally {4;}"));
+assertUndef(eval("function blah() { 1; }; blah();"));
+assertUndef(eval("var x = 1;"));
+assertEquals(1, eval("if (true) { 1; } else { 2; }"));
+assertEquals(2, eval("if (false) { 1; } else { 2; }"));
+assertUndef(eval("try{1; if (true) { 2; throw ''; } else { 2; }} catch(e){}"));
+assertEquals(2, eval("1; var i = 0; do { ++i; 2; } while(i!=1);"));
+assertUndef(eval(
+    "try{1; var i = 0; do { ++i; 2; throw ''; } while (i!=1);} catch(e){}"));
+assertUndef(eval("1; try{2; throwOnReturn();} catch(e){}"));
+assertUndef(eval("1; twoFunc();"));
+assertEquals(2, eval("1; with ( { a: 0 } ) { 2; }"));