Implement ES6 Template Literals

test/mjsunit/es6/templates.js

Index: test/mjsunit/es6/templates.js
diff --git a/test/mjsunit/es6/templates.js b/test/mjsunit/es6/templates.js
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+++ b/test/mjsunit/es6/templates.js
@@ -0,0 +1,321 @@
+// Copyright 2014 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-templates
+
+var num = 5;
+var str = "str";
+function fn() { return "result"; }
+var obj = {
+  num: num,
+  str: str,
+  fn: function() { return "result"; }
+};
+
+(function testBasicExpressions() {
+  assertEquals("foo 5 bar", `foo ${num} bar`);
+  assertEquals("foo str bar", `foo ${str} bar`);
+  assertEquals("foo [object Object] bar", `foo ${obj} bar`);
+  assertEquals("foo result bar", `foo ${fn()} bar`);
+  assertEquals("foo 5 bar", `foo ${obj.num} bar`);
+  assertEquals("foo str bar", `foo ${obj.str} bar`);
+  assertEquals("foo result bar", `foo ${obj.fn()} bar`);
+})();
+
+(function testExpressionsContainingTemplates() {
+  assertEquals("foo bar 5", `foo ${`bar ${num}`}`);
+})();
+
+(function testMultilineTemplates() {
+  assertEquals("foo\n    bar\n    baz", `foo
+    bar
+    baz`);
+
+  assertEquals("foo\n  bar\n  baz", eval("`foo\r\n  bar\r  baz`"));
+})();
+
+(function testLineContinuation() {
+  assertEquals("\n", `\
+
+`);
+})();
+
+(function testTaggedTemplates() {
+  var calls = 0;
+  (function(s) {
+    calls++;
+  })`test`;
+  assertEquals(1, calls);
+
+  calls = 0;
+  // assert tag is invoked in right context
+  obj = {
+    fn: function() {
+      calls++;
+      assertEquals(obj, this);
+    }
+  };
+
+  obj.fn`test`;
+  assertEquals(1, calls);
+
+  calls = 0;
+  // Simple templates only have a callSiteObj
+  (function(s) {
+    calls++;
+    assertEquals(1, arguments.length);
+  })`test`;
+  assertEquals(1, calls);
+
+  // Templates containing expressions have the values of evaluated expressions
+  calls = 0;
+  (function(site, n, s, o, f, r) {
+    calls++;
+    assertEquals(6, arguments.length);
+    assertEquals("number", typeof n);
+    assertEquals("string", typeof s);
+    assertEquals("object", typeof o);
+    assertEquals("function", typeof f);
+    assertEquals("result", r);
+  })`${num}${str}${obj}${fn}${fn()}`;
+  assertEquals(1, calls);
+
+  // The TV and TRV of NoSubstitutionTemplate :: `` is the empty code unit
+  // sequence.
+  calls = 0;
+  (function(s) {
+    calls++;
+    assertEquals(1, s.length);
+    assertEquals(1, s.raw.length);
+    assertEquals("", s[0]);
+
+    // Failure: expected <""> found <"foo  barfoo  barfoo foo foo foo testtest">
+    assertEquals("", s.raw[0]);
+  })``;
+  assertEquals(1, calls);
+
+  // The TV and TRV of TemplateHead :: `${ is the empty code unit sequence.
+  calls = 0;
+  (function(s) {
+    calls++;
+    assertEquals(2, s.length);
+    assertEquals(2, s.raw.length);
+    assertEquals("", s[0]);
+    assertEquals("", s.raw[0]);
+  })`${1}`;
+  assertEquals(1, calls);
+
+  // The TV and TRV of TemplateMiddle :: }${ is the empty code unit sequence.
+  calls = 0;
+  (function(s) {
+    calls++;
+    assertEquals(3, s.length);
+    assertEquals(3, s.raw.length);
+    assertEquals("", s[1]);
+    assertEquals("", s.raw[1]);
+  })`${1}${2}`;
+  assertEquals(1, calls);
+
+  // The TV and TRV of TemplateTail :: }` is the empty code unit sequence.
+  calls = 0;
+  (function(s) {
+    calls++;
+    assertEquals(2, s.length);
+    assertEquals(2, s.raw.length);
+    assertEquals("", s[1]);
+    assertEquals("", s.raw[1]);
+  })`${1}`;
+  assertEquals(1, calls);
+
+  // The TV of NoSubstitutionTemplate :: ` TemplateCharacters ` is the TV of
+  // TemplateCharacters.
+  calls = 0;
+  (function(s) { calls++; assertEquals("foo", s[0]); })`foo`;

[arv (Not doing code reviews), 2014/11/12 16:19:10]

I didn't imply that you need to add this to all your functions. I only suggested
that you replace the boolean one above.

[caitp (gmail), 2014/11/12 16:37:05]

Yeah, but I think it doesn't hurt for the other cases, since there are slight
differences in the parsed pattern, it's good to be thorough. It's a bit
redundant, but that's great in tests, so long as it's not problematic

+  assertEquals(1, calls);
+
+  // The TV of TemplateHead :: ` TemplateCharacters ${ is the TV of
+  // TemplateCharacters.
+  calls = 0;
+  (function(s) { calls++; assertEquals("foo", s[0]); })`foo${1}`;
+  assertEquals(1, calls);
+
+  // The TV of TemplateMiddle :: } TemplateCharacters ${ is the TV of
+  // TemplateCharacters.
+  calls = 0;
+  (function(s) { calls++; assertEquals("foo", s[1]); })`${1}foo${2}`;
+  assertEquals(1, calls);
+
+  // The TV of TemplateTail :: } TemplateCharacters ` is the TV of
+  // TemplateCharacters.
+  calls = 0;
+  (function(s) { calls++; assertEquals("foo", s[1]); })`${1}foo`;
+  assertEquals(1, calls);
+
+  // The TV of TemplateCharacters :: TemplateCharacter is the TV of
+  // TemplateCharacter.
+  calls = 0;
+  (function(s) { calls++; assertEquals("f", s[0]); })`f`;
+  assertEquals(1, calls);
+
+  // The TV of TemplateCharacter :: $ is the code unit value 0x0024.
+  calls = 0;
+  (function(s) { calls++; assertEquals("$", s[0]); })`$`;
+  assertEquals(1, calls);
+
+  // The TV of TemplateCharacter :: \ EscapeSequence is the CV of 
+  // EscapeSequence.
+  calls = 0;
+  (function(s) { calls++; assertEquals("안녕", s[0]); })`\uc548\uB155`;
+  (function(s) { calls++; assertEquals("\xff", s[0]); })`\xff`;
+  (function(s) { calls++; assertEquals("\n", s[0]); })`\n`;
+  assertEquals(3, calls);
+
+  // The TV of TemplateCharacter :: LineContinuation is the TV of
+  // LineContinuation. The TV of LineContinuation :: \ LineTerminatorSequence is
+  // the empty code unit sequence.
+  calls = 0;
+  (function(s) { calls++; assertEquals("", s[0]); })`\
+`;
+  assertEquals(1, calls);
+
+  // The TRV of NoSubstitutionTemplate :: ` TemplateCharacters ` is the TRV of
+  // TemplateCharacters.
+  calls = 0;
+  (function(s) { calls++; assertEquals("test", s.raw[0]); })`test`;
+  assertEquals(1, calls);
+
+  // The TRV of TemplateHead :: ` TemplateCharacters ${ is the TRV of
+  // TemplateCharacters.
+  calls = 0;
+  (function(s) { calls++; assertEquals("test", s.raw[0]); })`test${1}`;
+  assertEquals(1, calls);
+
+  // The TRV of TemplateMiddle :: } TemplateCharacters ${ is the TRV of
+  // TemplateCharacters.
+  calls = 0;
+  (function(s) { calls++; assertEquals("test", s.raw[1]); })`${1}test${2}`;
+  assertEquals(1, calls);
+
+  // The TRV of TemplateTail :: } TemplateCharacters ` is the TRV of
+  // TemplateCharacters.
+  calls = 0;
+  (function(s) { calls++; assertEquals("test", s.raw[1]); })`${1}test`;
+  assertEquals(1, calls);
+
+  // The TRV of TemplateCharacters :: TemplateCharacter is the TRV of
+  // TemplateCharacter.
+  calls = 0;
+  (function(s) { calls++; assertEquals("f", s.raw[0]); })`f`;
+  assertEquals(1, calls);
+
+  // The TRV of TemplateCharacter :: $ is the code unit value 0x0024.
+  calls = 0;
+  (function(s) { calls++; assertEquals("\u0024", s.raw[0]); })`$`;
+  assertEquals(1, calls);
+
+  // The TRV of EscapeSequence :: 0 is the code unit value 0x0030.
+  calls = 0;
+  (function(s) { calls++; assertEquals("\u005C\u0030", s.raw[0]); })`\0`;
+  assertEquals(1, calls);
+
+  // The TRV of TemplateCharacter :: \ EscapeSequence is the sequence consisting
+  // of the code unit value 0x005C followed by the code units of TRV of
+  // EscapeSequence.
+
+  //   The TRV of EscapeSequence :: HexEscapeSequence is the TRV of the
+  //   HexEscapeSequence.
+  calls = 0;
+  (function(s) { calls++; assertEquals("\u005Cxff", s.raw[0]); })`\xff`;
+  assertEquals(1, calls);
+
+  //   The TRV of EscapeSequence :: UnicodeEscapeSequence is the TRV of the
+  //   UnicodeEscapeSequence.
+  calls = 0;
+  (function(s) { calls++; assertEquals("\u005Cuc548", s.raw[0]); })`\uc548`;
+  assertEquals(1, calls);
+
+  //   The TRV of CharacterEscapeSequence :: SingleEscapeCharacter is the TRV of
+  //   the SingleEscapeCharacter.
+  calls = 0;
+  (function(s) { calls++; assertEquals("\u005C\u0027", s.raw[0]); })`\'`;
+  (function(s) { calls++; assertEquals("\u005C\u0022", s.raw[0]); })`\"`;
+  (function(s) { calls++; assertEquals("\u005C\u005C", s.raw[0]); })`\\`;
+  (function(s) { calls++; assertEquals("\u005Cb", s.raw[0]); })`\b`;
+  (function(s) { calls++; assertEquals("\u005Cf", s.raw[0]); })`\f`;
+  (function(s) { calls++; assertEquals("\u005Cn", s.raw[0]); })`\n`;
+  (function(s) { calls++; assertEquals("\u005Cr", s.raw[0]); })`\r`;
+  (function(s) { calls++; assertEquals("\u005Ct", s.raw[0]); })`\t`;
+  (function(s) { calls++; assertEquals("\u005Cv", s.raw[0]); })`\v`;
+  (function(s) { calls++; assertEquals("\u005C`", s.raw[0]); })`\``;
+  assertEquals(10, calls);
+
+  //   The TRV of CharacterEscapeSequence :: NonEscapeCharacter is the CV of the
+  //   NonEscapeCharacter.
+  calls = 0;
+  (function(s) { calls++; assertEquals("\u005Cx", s.raw[0]); })`\x`;
+  assertEquals(1, calls);
+
+  // The TRV of LineTerminatorSequence :: <LF> is the code unit value 0x000A.
+  // The TRV of LineTerminatorSequence :: <CR> is the code unit value 0x000A.
+  // The TRV of LineTerminatorSequence :: <CR><LF> is the sequence consisting of
+  // the code unit value 0x000A.
+  calls = 0;
+  function testRawLineNormalization(cs) {
+    calls++;
+    assertEquals(cs.raw[0], "\n\n\n");
+    assertEquals(cs.raw[1], "\n\n\n");
+  }
+  eval("testRawLineNormalization`\r\n\n\r${1}\r\n\n\r`");
+  assertEquals(1, calls);
+
+  // The TRV of LineContinuation :: \ LineTerminatorSequence is the sequence
+  // consisting of the code unit value 0x005C followed by the code units of TRV
+  // of LineTerminatorSequence.
+  calls = 0;
+  function testRawLineContinuation(cs) {
+    calls++;
+    assertEquals(cs.raw[0], "\u005C\n\u005C\n\u005C\n");
+    assertEquals(cs.raw[1], "\u005C\n\u005C\n\u005C\n");
+  }
+  eval("testRawLineContinuation`\\\r\n\\\n\\\r${1}\\\r\n\\\n\\\r`");
+  assertEquals(1, calls);
+})();
+
+
+(function testCallSiteObj() {
+  var calls = 0;
+  function tag(cs) {
+    calls++;
+    assertTrue("raw" in cs);

[arv (Not doing code reviews), 2014/11/12 16:19:10]

Generally, prefer hasOwnProperty or getOwnPropertyDescription since in can imply
that the property is available in the prototype chain.

[caitp (gmail), 2014/11/12 16:37:05]

Acknowledged.

+    assertTrue(Object.isFrozen(cs));
+    assertTrue(Object.isFrozen(cs.raw));
+    cs[1] = true;

[arv (Not doing code reviews), 2014/11/12 16:19:10]

A better way to test for read only is to assert that the property descriptor has
writable == false.

[caitp (gmail), 2014/11/12 16:37:05]

Changed it to assert values of property descriptor properties instead

+    cs.raw[1] = true;
+    cs.length = 10;
+    cs.raw.length = 10;
+    assertEquals("", cs[1]);
+    assertEquals("", cs.raw[1]);
+    assertEquals(2, cs.length);
+    assertEquals(2, cs.raw.length);
+  }
+  tag`${1}`;
+  assertEquals(1, calls);
+})();
+
+
+(function testUTF16ByteOrderMark() {
+  assertEquals("\uFEFFtest", `\uFEFFtest`);
+  assertEquals("\uFEFFtest", eval("`\uFEFFtest`"));
+})();
+
+
+(function testExtendedArrayPrototype() {
+  Object.defineProperty(Array.prototype, 0, {
+    set: function() {
+      assertUnreachable();
+    }
+  });
+  function tag(){}
+  tag`a${1}b`;
+})();