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
+
+
+function assertUndef(x) {

[rossberg, 2015/10/05 11:33:00]

Can we also have tests that check for the correct non-undef values in other
cases, especially with uses of break?

[neis, 2015/10/07 11:58:40]

I added some. There's also a bunch in harmony/block-for-sloppy.

+  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
+
+
+// IterationStatement [13.7] (a few of them)
+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; 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

[rossberg, 2015/10/05 11:33:00]

No tests for for-let, for-of, for-in?

[neis, 2015/10/07 11:58:40]

Done.

+
+
+// WithStatement [13.11.7]
+assertUndef(eval('42; with ({}) ;'));  // ES5: 42
+
+
+// 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(0, eval('42; switch (0) { case 0: 0; }'));
+assertEquals(0, eval('42; switch (0) { case 0: 0; 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 Error } catch(e) { };'));  // ES5: 42
+assertUndef(eval('42; try { throw Error } catch(e) { } finally { };'));  // ES5: 42
+
+
+// Some combinations

[rossberg, 2015/10/05 11:33:00]

Can we have more of those? There probably are various cases with breaks
somewhere in the middle that you want to test.

[neis, 2015/10/07 11:58:40]

Added some.  There's also a bunch in harmony/block-for-sloppy and in the stuff
copied from webkit.

+assertUndef(eval('42; switch (0) { case 0: if (true) break; }'));  // ES5: 42
+assertUndef(eval('42; switch (0) { case 0: 0; if (true) ; }'));  // ES5: 0
+assertUndef(eval('42; switch (0) { case 0: 0; try { break } catch(e) { }; }'));  // ES5: 0
+
+// The following is not what ES6 says, but see ES bug 4540.
+assertUndef(eval('42; switch (0) { case 0: 0; if (true) break; }'));  // ES5: 0
+
+
+
+/////////////////////////////////////////////////////////////////////////////////

[rossberg, 2015/10/05 11:33:00]

Nit: line length

[neis, 2015/10/07 11:58:40]

Done.

+//
+// 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){}"));

[rossberg, 2015/10/05 11:33:00]

Line length

[neis, 2015/10/07 11:58:40]

Done.

+assertUndef(eval("1; try{2; throwOnReturn();} catch(e){}"));
+assertUndef(eval("1; twoFunc();"));
+assertEquals(2, eval("1; with ( { a: 0 } ) { 2; }"));