Prior to this commit, two tests for specific early errors also included
syntactically invalid `const` declarations. Implementations which
produced the expected syntax error due to these invalid declarations
would pass the tests regardless of whether they produced the early
errors that the tests were written to verify.
Correct the `const` declarations so that the tests verify the parsing
rule that they were designed to verify.
The test as originally specified fails in all compatible parsers, but for the wrong reason. Below is an excerpt from V8, but all parser I tested behave the same:
```js
for (const x; false; ) {
^
SyntaxError: Missing initializer in const declaration
```
After the change the error is the assumed:
```js
var x;
^
SyntaxError: Identifier 'x' has already been declared
```
Previously, some tests verified two independent concerns simultaneously:
syntactic validity and runtime completion value. The former is relevant
for ECMAScript runtimes and parsers alike, but the latter is only
observable by runtimes.
Express expectations regarding syntactic validity using literal program
code so they can be used by parsers. Maintain the original tests which
rely on eval in order to preserve coverage for statement completion
values.
Early errors may result from parsing the source text of a test file, but
they may also result from parsing some other source text as referenced
through the ES2015 module syntax. The latter form of early error is not
necessarily detectable by ECMAScript parsers, however. Because of this,
the label "early" is not sufficiently precise for all Test262 consumers
to correctly interpret all tests.
Update the "phase" name of "early" to "parse" for all those negative
tests that describe errors resulting from parsing of the file's source
text directly. A forthcoming commit will update the remaining tests to
use a "phase" name that is more specific to module resolution.
Authored via the following command:
$ find test -type f -print0 | \
xargs -0 sed \
-i 's/^\(\s*\)negative:\s*SyntaxError\s*$/\1negative:\n\1 phase: early\n\1 type: SyntaxError/g'
* Extend tests for class "name" inference
Ensure that when a class defines a static "name" method, that method
definition prevents the "name" inference behavior.
* Re-generate tests
Ensure that early errors restricting labelled function declarations
within WithStatement and IfStatement are honored. Rename existing tests
to match the specification's spelling.
Add tests that assert the management of the running execution context's
LexicalEnvironment and VariableEnvironment components, as created by the
following abstract operations:
- NewDeclarativeEnvironment
- NewObjectEnvironment
- NewFunctionEnvironment
Many tests require the use of non-strict direct eval, meaning they may
not be run in strict mode. This does not effect coverage because the
semantics in these cases are not observable from strict mode code.
Some situations require the creation of a binding, but this binding has
no relevance to the test itself. In these cases, use names consisting
solely of the underscore character (`_`).
Avoid the use of Block statements wherever possible, as these trigger
the creation of additional environments which may interfere with the
behavior under test.
- Prefix file names to explicitly describe the "head" position
- Remove statement name suffix as this information is reflected by each
file's location within the file hierarchy
ECMAScript 2015 introduced tail call optimization for function calls
occuring in a number of positions in the grammar. Assert expected
behavior by triggering a large (but configurable) number of recursive
function calls in these positions. Compliant runtimes will execute such
programs without error; non-compliant runtimes are expected to fail
these tests by throwing an error or crashing when system resources are
exhausted.
The ES2016 draft further refines the completion values for `if` and
`with` statements. Two tests must be removed outright because the
completion value in those cases is no longer accessible from the
runtime.
In order to facilitate proper tail calls, ES2015 modified the completion
value of a number of statements.
These tests use `eval` to verify the new values.
Mike Pennisi
Dmitriy Kubyshkin
rwaldron
Kevin Gibbons
Alexey Shvayka
Leo Balter
Mathias Bynens
André Bargull
Tom Care
Gorkem Yakin