add Function.prototype.toString tests, conforming to proposed revision

See the proposal at
https://tc39.github.io/Function-prototype-toString-revision/

harness/nativeFunctionMatcher.js

+const NATIVE_FUNCTION_RE = /\bfunction\b[\s\S]+\b\w+\b[\s\S]*\([\s\S]*\)[\s\S]*\{[\s\S]*\[[\s\S]*\bnative\b[\s\S]+\bcode\b[\s\S]*\][\s\S]*\}/;

test/built-ins/Function/prototype/toString/Function.js

+// Copyright (C) 2016 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-createdynamicfunction
+description: Function.prototype.toString on a function created with the Function constructor
+---*/
+
+let f = /* before */Function("a", " /* a */ b, c /* b */ //", "/* c */ ; /* d */ //")/* after */;
+
+assert.sameValue(f.toString(), "function anonymous(a, /* a */ b, c /* b */ //\n) {/* c */ ; /* d */ //\n}");

test/built-ins/Function/prototype/toString/GeneratorFunction.js

+// Copyright (C) 2016 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-createdynamicfunction
+description: Function.prototype.toString on a generator function created with the GeneratorFunction constructor
+---*/
+
+let GeneratorFunction = Object.getPrototypeOf(function*(){}).constructor;
+let g = /* before */GeneratorFunction("a", " /* a */ b, c /* b */ //", "/* c */ yield yield; /* d */ //")/* after */;
+
+assert.sameValue(g.toString(), "function* anonymous(a, /* a */ b, c /* b */ //\n) {/* c */ yield yield; /* d */ //\n}");

test/built-ins/Function/prototype/toString/S15.3.4.2_A12.js

@@ -5,7 +5,7 @@
 es5id: 15.3.4.2_A12
 description: >
     The Function.prototype.toString function is not generic; it throws
-    a TypeError exception if its this value is not a Function object.
+    a TypeError exception if its this value is not a callable object.
 ---*/
 
 assert.throws(TypeError, function() {

test/built-ins/Function/prototype/toString/S15.3.4.2_A13.js

@@ -5,7 +5,7 @@
 es5id: 15.3.4.2_A13
 description: >
     The toString function is not generic; it throws a TypeError
-    exception if its this value is not a Function object.
+    exception if its this value is not a callable object.
 ---*/
 
 assert.throws(TypeError, function() {

test/built-ins/Function/prototype/toString/S15.3.4.2_A14.js

@@ -5,7 +5,7 @@
 es5id: 15.3.4.2_A14
 description: >
     The toString function is not generic; it throws a TypeError
-    exception if its this value is not a Function object.
+    exception if its this value is not a callable object.
 ---*/
 
 assert.throws(TypeError, function() {

test/built-ins/Function/prototype/toString/S15.3.4.2_A15.js

-// Copyright 2011 the Sputnik authors.  All rights reserved.
-// This code is governed by the BSD license found in the LICENSE file.
-
-/*---
-info: >
-    The toString function is not generic; it throws a TypeError exception if
-    its this value is not a Function object.
-es5id: 15.3.4.2_A15
-description: >
-    Whether or not they are callable, RegExp objects are not Function
-    objects, so toString should throw a TypeError.
----*/
-
-assert.throws(TypeError, function() {
-  Function.prototype.toString.call(/x/);
-});

test/built-ins/Function/prototype/toString/S15.3.4.2_A16.js

@@ -4,7 +4,7 @@
 /*---
 info: >
     The toString function is not generic; it throws a TypeError exception if
-    its this value is not a Function object.
+    its this value is not a callable object.
 es5id: 15.3.4.2_A16
 description: >
     The String constructor, given an object, should invoke that

test/built-ins/Function/prototype/toString/arrow-function.js

+// Copyright (C) 2016 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-arrow-function-definitions-runtime-semantics-evaluation
+description: Function.prototype.toString on an arrow function
+---*/
+
+let f = /* before */( /* a */ a /* b */ , /* c */ b /* d */ ) /* e */ => /* f */ { /* g */ ; /* h */ }/* after */;
+let g = /* before */( /* a */ ) /* b */ => /* c */ 0/* after */;
+let h = /* before */a /* a */ => /* b */ 0/* after */;
+
+assert.sameValue(f.toString(), "( /* a */ a /* b */ , /* c */ b /* d */ ) /* e */ => /* f */ { /* g */ ; /* h */ }");
+assert.sameValue(g.toString(), "( /* a */ ) /* b */ => /* c */ 0");
+assert.sameValue(h.toString(), "a /* a */ => /* b */ 0");

test/built-ins/Function/prototype/toString/bound-function.js

+// Copyright (C) 2016 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-function.prototype.tostring
+description: Function.prototype.toString on bound function exotic objects
+includes: [nativeFunctionMatcher.js]
+---*/
+
+let f = function(){}.bind(null);
+
+assert(NATIVE_FUNCTION_RE.test("" + f), "looks pretty much like a NativeFunction");

test/built-ins/Function/prototype/toString/class-declaration-complex-heritage.js

+// Copyright (C) 2016 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-runtime-semantics-bindingclassdeclarationevaluation
+description: Function.prototype.toString on a class declaration (with complex heritage)
+---*/
+
+/* before */class /* a */ A /* b */ extends /* c */ class /* d */ B /* e */ { /* f */ } /* g */ { /* h */ }/* after */
+
+assert.sameValue(A.toString(), "class /* a */ A /* b */ extends /* c */ class /* d */ B /* e */ { /* f */ } /* g */ { /* h */ }");

test/built-ins/Function/prototype/toString/class-declaration-explicit-ctor.js

+// Copyright (C) 2016 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-runtime-semantics-bindingclassdeclarationevaluation
+description: Function.prototype.toString on a class declaration (explicit constructor)
+---*/
+
+/* before */class /* a */ A /* b */ extends /* c */ B /* d */ { /* e */ constructor /* f */ ( /* g */ ) /* h */ { /* i */ ; /* j */ } /* k */ m /* l */ ( /* m */ ) /* n */ { /* o */ } /* p */ }/* after */
+
+assert.sameValue(A.toString(), "class /* a */ A /* b */ extends /* c */ B /* d */ { /* e */ constructor /* f */ ( /* g */ ) /* h */ { /* i */ ; /* j */ } /* k */ m /* l */ ( /* m */ ) /* n */ { /* o */ } /* p */ }");
+
+function B(){}

test/built-ins/Function/prototype/toString/class-declaration-implicit-ctor.js

+// Copyright (C) 2016 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-runtime-semantics-bindingclassdeclarationevaluation
+description: Function.prototype.toString on a class declaration (implicit constructor)
+---*/
+
+/* before */class /* a */ A /* b */ { /* c */ }/* after */
+/* before */class /* a */ B /* b */ extends /* c */ A /* d */ { /* e */ }/* after */
+/* before */class /* a */ C /* b */ extends /* c */ B /* d */ { /* e */ m /* f */ ( /* g */ ) /* h */ { /* i */ } /* j */ }/* after */
+
+assert.sameValue(A.toString(), "class /* a */ A /* b */ { /* c */ }");
+assert.sameValue(B.toString(), "class /* a */ B /* b */ extends /* c */ A /* d */ { /* e */ }");
+assert.sameValue(C.toString(), "class /* a */ C /* b */ extends /* c */ B /* d */ { /* e */ m /* f */ ( /* g */ ) /* h */ { /* i */ } /* j */ }");

test/built-ins/Function/prototype/toString/class-expression-explicit-ctor.js

+// Copyright (C) 2016 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-class-definitions-runtime-semantics-evaluation
+description: Function.prototype.toString on a class expression (explicit constructor)
+---*/
+
+let A = /* before */class /* a */ A /* b */ extends /* c */ B /* d */ { /* e */ constructor /* f */ ( /* g */ ) /* h */ { /* i */ ; /* j */ } /* k */ m /* l */ ( /* m */ ) /* n */ { /* o */ } /* p */ }/* after */;
+
+assert.sameValue(A.toString(), "class /* a */ A /* b */ extends /* c */ B /* d */ { /* e */ constructor /* f */ ( /* g */ ) /* h */ { /* i */ ; /* j */ } /* k */ m /* l */ ( /* m */ ) /* n */ { /* o */ } /* p */ }");
+
+function B(){}

test/built-ins/Function/prototype/toString/class-expression-implicit-ctor.js

+// Copyright (C) 2016 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-class-definitions-runtime-semantics-evaluation
+description: Function.prototype.toString on a class expression (implicit constructor)
+---*/
+
+let A = /* before */class /* a */ A /* b */ { /* c */ }/* after */;
+let B = /* before */class /* a */ B /* b */ extends /* c */ A /* d */ { /* e */ }/* after */;
+let C = /* before */class /* a */ C /* b */ extends /* c */ B /* d */ { /* e */ m /* f */ ( /* g */ ) /* h */ { /* i */ } /* j */ }/* after */;
+
+assert.sameValue(A.toString(), "class /* a */ A /* b */ { /* c */ }");
+assert.sameValue(B.toString(), "class /* a */ B /* b */ extends /* c */ A /* d */ { /* e */ }");
+assert.sameValue(C.toString(), "class /* a */ C /* b */ extends /* c */ B /* d */ { /* e */ m /* f */ ( /* g */ ) /* h */ { /* i */ } /* j */ }");

test/built-ins/Function/prototype/toString/function-declaration-non-simple-parameter-list.js

+// Copyright (C) 2016 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-function-definitions-runtime-semantics-instantiatefunctionobject
+description: Function.prototype.toString on a function with a non-simple parameter list
+---*/
+
+/* before */function /* a */ f /* b */ ( /* c */ a /* d */ = /* e */ 0 /* f */ , /* g */ { /* h */ b /* i */ = /* j */ 0 /* k */ } /* l */ ) /* m */ { /* n */ }/* after */
+
+assert.sameValue(f.toString(), "function /* a */ f /* b */ ( /* c */ a /* d */ = /* e */ 0 /* f */ , /* g */ { /* h */ b /* i */ = /* j */ 0 /* k */ } /* l */ ) /* m */ { /* n */ }");

test/built-ins/Function/prototype/toString/function-declaration.js

+// Copyright (C) 2016 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-function-definitions-runtime-semantics-instantiatefunctionobject
+description: Function.prototype.toString on a function declaration
+---*/
+
+/* before */function /* a */ f /* b */ ( /* c */ x /* d */ , /* e */ y /* f */ ) /* g */ { /* h */ ; /* i */ ; /* j */ }/* after */
+
+assert.sameValue(f.toString(), "function /* a */ f /* b */ ( /* c */ x /* d */ , /* e */ y /* f */ ) /* g */ { /* h */ ; /* i */ ; /* j */ }");

test/built-ins/Function/prototype/toString/function-expression.js

+// Copyright (C) 2016 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-function-definitions-runtime-semantics-evaluation
+description: Function.prototype.toString on a function expression
+---*/
+
+let f = /* before */function /* a */ f /* b */ ( /* c */ x /* d */ , /* e */ y /* f */ ) /* g */ { /* h */ ; /* i */ ; /* j */ }/* after */;
+
+assert.sameValue(f.toString(), "function /* a */ f /* b */ ( /* c */ x /* d */ , /* e */ y /* f */ ) /* g */ { /* h */ ; /* i */ ; /* j */ }");

test/built-ins/Function/prototype/toString/generator-function-declaration.js

+// Copyright (C) 2016 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-generator-function-definitions-runtime-semantics-instantiatefunctionobject
+description: Function.prototype.toString on a generator function declaration
+---*/
+
+/* before */function /* a */ * /* b */ g /* c */ ( /* d */ x /* e */ , /* f */ y /* g */ ) /* h */ { /* i */ ; /* j */ ; /* k */ }/* after */
+
+assert.sameValue(g.toString(), "function /* a */ * /* b */ g /* c */ ( /* d */ x /* e */ , /* f */ y /* g */ ) /* h */ { /* i */ ; /* j */ ; /* k */ }");

test/built-ins/Function/prototype/toString/generator-function-expression.js

+// Copyright (C) 2016 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-generator-function-definitions-runtime-semantics-evaluation
+description: Function.prototype.toString on a generator function expression
+---*/
+
+let g = /* before */function /* a */ * /* b */ name /* c */ ( /* d */ x /* e */ , /* f */ y /* g */ ) /* h */ { /* i */ ; /* j */ ; /* k */ }/* after */
+
+assert.sameValue(g.toString(), "function /* a */ * /* b */ name /* c */ ( /* d */ x /* e */ , /* f */ y /* g */ ) /* h */ { /* i */ ; /* j */ ; /* k */ }");