Files whose name ends in `_.js` are not themselves valid Test262 tests
and should not be interpreted as such by test runners.
---
The tests for the GetBindingValue method of the module Environment
Record are very minimal. This is because GetBindingValue is necessary to
assert any aspect of binding creation/initialization/mutation. In this
way, GetBindingValue is being implicitly tested by every test that
references a binding value.
Files whose name ends in `_.js` are not themselves valid Test262 tests
and should not be interpreted as such by test runners.
---
Because the tests in this patch concern declaration *instantiation*,
care has been taken to avoid asserting binding values following
evaluation. Because a given module's dependencies are evaluated prior to
the module itself, this is only observable in modules which import their
own bindings.
A separate patch dedicated to the evaluation of module code asserts the
behavior of bindings following evaluation.
---
For tests that concern the creation of a module namespace object, this
patch relies on the semantics of the `in` operator. The `in` operator
uses the [[HasProperty]] internal method and avoids testing unrelated
semantics concerning binding resolution. Those semantics should be
explicitly asserted with a separate set of tests dedicated to that
purpose.
---
One test case which is notably missing is error resulting from a cycle
due to an `import` declaration (under the current file naming scheme,
such a test might be named `instn-named-err-circular.js`). Due to the
recursive nature of ModuleDeclarationInstantiation, it is not
technically possible for a circular request to be found in step 12.c.i.
Cycles rely on at least 2 `export` declarations, and because these are
resolved *before* imports, any cycle would trigger failure prior to step
12.c.
---
One aspect of *module* resolution that makes ordering observable is the
fact that resolution can fail in two distinct ways (i.e. with a
SyntaxError or with a ReferenceError). This patch includes tests that
leverage this detail in order to assert that modules are resolved in the
correct sequence.
However, from the perspective of the ECMA-262 specification, the
ordering of *export* (e.g. binding) resolution is not observable. This
is due to restrictions on the grammar, where each export is independent.
When *export* resolution fails, it does so with instances of SyntaxError
alone, precluding the above strategy.
So while ModuleDeclarationInstantiation resolves the exports of the
module's dependencies in the following order:
1. "Indirect" exports, e.g.
- `export { x } from './y.js';`
- `export { x as z } from './y.js';`
- `import { x } from './y.js'; export { x };`
2. "Star" imports
- `import * as ns from './y.js';`
3. "Named" (my word) imports
- `import x from './y.js';`
- `import { x } from './y.js';`
- `import { x as z } from './y.js';`
Intentional failures cannot be used to discern resolution ordering.
The runtime semantics of this statement are host-defined and therefore
untestable, but the statement's affect on the formal grammar should be
consistent across all implementations.
V8 ran into an issue where the YAML parser our test setup is using
didn't understand the newline, and failed to parser the negative
test expectation below, causing the test to fail. This patch fixes
the issue.
Assert that ImportDeclaration and ExportDeclaration match only the
ModuleItem symbol.
According to the definition of HostResolveImportedModule, it is
acceptable for an implementation to throw a SyntaxError in the event
that a requested module can neither be found nor created:
> If a Module Record corresponding to the pair referencingModule,
> specifier does not exist or cannot be created, an exception must be
> thrown.
In order to reliably detect a SyntaxError in response to the correct
interpretation of the grammar (and not a SyntaxError from an *incorrect*
interpretation of the grammar followed by a failure to resolve the
requested module), the ModuleSpecifier of ExportDeclarations should
describe a valid resource.
- 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
The harness file `Test262Error.js` has not contained executable code since it
was introduced in this project [1]. The definition of the `Test262Error`
function has consistently been located in the `sta.js` harness file which test
runners are expected to inject into the test environment.
Remove the file and all references to it.
[1] See commit c33bf0e0439e6f6bf084c1524d7df8d2b41c515d
Test262 defines tests for expression-producing syntactic forms within
the `language/expressions/` directory. Most tests for object literals
conform to this structure, but 12 such tests were added to the
`language/object-literal/` directory. Move these tests to the canonical
location for object literals.
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.
Although the `for..in` statement allows Expressions to define the
iterator, only an AssignmentExpression may occupy this position in the
`for..of` statement.
