When eagerly parsing arrow functions, expressions in default
parameter initializers are parsed in the enclosing scope,
rather than in the function's scope (since that scope does not
yet exist). This leads to VariableProxies being added to the
wrong scope, and scope chains for FunctionLiterals being incorrect.
This patch addresses these problems by adding a subclass of
AstExpressionVisitor that moves VariableProxies to the proper
scope and fixes up scope chains of FunctionLiterals.
This is a revert of the revert https://crrev.com/e41614a058426fb6102e4ab2dd4f98997f00c0fc
with a much-improved (though not yet perfect) Scope::ResetOuterScope
method which properly fixes not only the outer_scope_ pointer but also
fixes the inner_scope_ list in the relevant outer_scopes.
More work likely still needs to be done to make this work completely,
but it's very close to correct.
BUG=v8:4395
LOG=y
Review URL: https://codereview.chromium.org/1414283002
Cr-Commit-Position: refs/heads/master@{#31435}
Reason for revert:
Breaks nosnap: http://build.chromium.org/p/client.v8/builders/V8%20Linux%20-%20nosnap%20-%20debug%20-%202/builds/2407/steps/Check/logs/regress-4395
Original issue's description:
> [es6] Fix scoping for default parameters in arrow functions
>
> When eagerly parsing arrow functions, expressions in default
> parameter initializers are parsed in the enclosing scope,
> rather than in the function's scope (since that scope does not
> yet exist). This leads to VariableProxies being added to the
> wrong scope, and scope chains for FunctionLiterals being incorrect.
>
> This patch addresses these problems by adding a subclass of
> AstExpressionVisitor that moves VariableProxies to the proper
> scope and fixes up scope chains of FunctionLiterals.
>
> More work likely still needs to be done to make this work completely,
> but it's very close to correct.
>
> BUG=v8:4395
> LOG=y
>
> Committed: https://crrev.com/cf72aad39e51de9b7074ea039377c1812f4a2c6b
> Cr-Commit-Position: refs/heads/master@{#31402}
TBR=rossberg@chromium.org,caitpotter88@gmail.com,adamk@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4395
Review URL: https://codereview.chromium.org/1417463004
Cr-Commit-Position: refs/heads/master@{#31404}
When eagerly parsing arrow functions, expressions in default
parameter initializers are parsed in the enclosing scope,
rather than in the function's scope (since that scope does not
yet exist). This leads to VariableProxies being added to the
wrong scope, and scope chains for FunctionLiterals being incorrect.
This patch addresses these problems by adding a subclass of
AstExpressionVisitor that moves VariableProxies to the proper
scope and fixes up scope chains of FunctionLiterals.
More work likely still needs to be done to make this work completely,
but it's very close to correct.
BUG=v8:4395
LOG=y
Review URL: https://codereview.chromium.org/1405313002
Cr-Commit-Position: refs/heads/master@{#31402}
Arrow functions have been enabled by default since the 4.5 branch.
Review URL: https://codereview.chromium.org/1373633002
Cr-Commit-Position: refs/heads/master@{#31031}
This adds the materialized literal count accumulated while parsing the
parameters (in the parser proper) to that accumulated by the preparser.
This should have been caught in cctest/test-parsing, but it's not covered
because the parsing tests call directly into the preparser rather than
using Parser::ParseFunctionLiteral (which fully-parses the parameters
and then calls into the preparser to skip over the function body).
Note that this further-inflates the materialized literal count for
functions with destructured arguments, since some of the counted
literals are actually binding patterns. But that's not specific to
binding patterns in formal parameters: it happens in function bodies, too.
BUG=v8:4400,v8:4407
LOG=n
Review URL: https://codereview.chromium.org/1350913005
Cr-Commit-Position: refs/heads/master@{#30868}
Mark ArrayLiterals utilizing the spread operator as non-simple.
This causes them to return false for IsCompileTimeValue, and thus
causes spread to work as expected in nested literals.
BUG=v8:4417
LOG=y
Review URL: https://codereview.chromium.org/1336123002
Cr-Commit-Position: refs/heads/master@{#30754}
To avoid tanking context startup performance, only the actual installation of the
JS-exposed API is flag-guarded. The remainder of the implementation still
resides in the snapshot.
Review URL: https://codereview.chromium.org/1257063003
Cr-Commit-Position: refs/heads/master@{#30017}
During parsing, we now keep track of the first spread seen in an array
literal (if any), and make use of that information when creating the
FixedArray backing store representing the constant elements for array
literal materialization.
The old code tried to do this by setting the generated JSArray's length
in ArrayLiteral::BuildConstantElements(), but that Array length is never
read by the rest of the literal materialization code (it always uses
the length of the FixedArray backing store).
BUG=v8:4298
LOG=n
Review URL: https://codereview.chromium.org/1225223004
Cr-Commit-Position: refs/heads/master@{#29684}
This fixes a corner-case where arrow functions that require a context
allocate none, because there are no additional slots allocated. Note
that this didn't happen with true function scopes because they always
had at least the receiver slot.
The outcome was a context chain that no longer was in sync with the
scope chain, hence context slot loads were bogus. This is observable
using the DYNAMIC_LOCAL optimization in all compilers.
R=rossberg@chromium.org,wingo@igalia.com
TEST=mjsunit/harmony/regress/regress-4160
BUG=v8:4160
LOG=N
Review URL: https://codereview.chromium.org/1146063006
Cr-Commit-Position: refs/heads/master@{#28788}
A strict arrow function with no parameters and no variable bindings
won't need a context object because it will never have any
locals. (This is unlike strict normal functions, which do have
"arguments" and "this" locals.)
R=rossberg@chromium.org
BUG=v8:4056
LOG=N
Review URL: https://codereview.chromium.org/1093183003
Cr-Commit-Position: refs/heads/master@{#28031}
Per TC39 Nov 2014 decision.
This patch also changes behavior for "legacy const": assignments to sloppy const in strict mode is now also a type error. This fixes v8:2243 and also brings us in compliance with other engines re assignment to function names (see updated webkit test), but might have bigger implications.
That change can easily be reverted by changing Variable::IsSignallingAssignmentToConst.
BUG=v8:3713,v8:2243
LOG=N
Review URL: https://codereview.chromium.org/749633002
Cr-Commit-Position: refs/heads/master@{#25516}
This requires putting the original loop's body inside an inner for loop (with
the same labels as the original loop) and re-binding the temp variables in its
"next" expression. A second flag is added to the desugared code to ensure the
loop body executes at most once per loop.
BUG=v8:3683
LOG=y
Review URL: https://codereview.chromium.org/720863002
Cr-Commit-Position: refs/heads/master@{#25363}
This is in preparation for making --harmony and --es-staging synonyms.
The only remaining difference currently is block-scoping, which is still
implied by --harmony, to avoid regressing on a long-available feature.
Also removes the special-casing of --harmony-proxies.
R=adamk@chromium.org
BUG=
Review URL: https://codereview.chromium.org/693153004
Cr-Commit-Position: refs/heads/master@{#25115}
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25115 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
All JSObjects in V8 either have a map()->constructor() field or are
JSFunctions. JSProxy::Fix, however, was not enforcing this, and
Object.observe's use of JSObject::GetCreationContext() exposed this.
Note that this is not Object.observe-specific: the API call
v8::Object::CreationContext() also would have revealed this bug.
This patch chooses Object as a reasonable constructor to put on the
newly-fixed object's map. Note that this has no effect on the "constructor"
property in JS. In doing so, I've also tightened up the code underlying
JSProxy::Fix to only support JSObject and JSFunction as possible output
types.
BUG=405844
LOG=N
R=rossberg@chromium.org, verwaest@chromium.org
Review URL: https://codereview.chromium.org/505303004
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23466 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
