Support ES2019 Array.prototype.flatMap

[midgleyc]

Closes #949.

I followed what I did in #1313 but for flatMap this time.

[rbri]

please run spotlessApply to have the code in the correct layout

[rbri]

Thanks for the PR; do you see any chance to get array-like-objects.js also passing - i think i have seen some code already dealing with array-like objects....

[midgleyc]

Array-like objects already work to some degree. There are four total test files:

array-like-objects.js
array-like-objects-nested.js
array-like-objects-typedarrays.js
array-like-objects-poisoned-length.js

Of those, the base and poisoned length fail, and the others pass. I'll see if I can spot why.

Poisoned length fails due to not supporting [Symbol.toPrimitive]. The base fails due to not supporting a property named [10000]. Looks like the [X] syntax in general. Probably #913.

[rbri]

@midgleyc build failed

org.mozilla.javascript.tests.MozillaSuiteTest > runMozillaTest[6550, js=testsrc/tests/js1_5/Regress/regress-89443.js, opt=9] STANDARD_ERROR
java.lang.StackOverflowError
at org.mozilla.javascript.optimizer.Optimizer.rewriteForNumberVariables(Optimizer.java)
at org.mozilla.javascript.optimizer.Optimizer.rewriteAsObjectChildren(Optimizer.java:409)
at org.mozilla.javascript.optimizer.Optimizer.rewriteForNumberVariables(Optimizer.java:393)
at org.mozilla.javascript.optimizer.Optimizer.rewriteAsObjectChildren(Optimizer.java:409)
at org.mozilla.javascript.optimizer.Optimizer.rewriteForNumberVariables(Optimizer.java:399)
at org.mozilla.javascript.optimizer.Optimizer.rewriteAsObjectChildren(Optimizer.java:409)
at org.mozilla.javascript.optimizer.Optimizer.rewriteForNumberVariables(Optimizer.java:399)
at org.mozilla.javascript.optimizer.Optimizer.rewriteAsObjectChildren(Optimizer.java:409)
at org.mozilla.javascript.optimizer.Optimizer.rewriteForNumberVariables(Optimizer.java:399)
at org.mozilla.javascript.optimizer.Optimizer.rewriteAsObjectChildren(Optimizer.java:409)
at org.mozilla.javascript.optimizer.Optimizer.rewriteForNumberVariables(Optimizer.java:399)
at org.mozilla.javascript.optimizer.Optimizer.rewriteAsObjectChildren(Optimizer.java:409)
at org.mozilla.javascript.optimizer.Optimizer.rewriteForNumberVariables(Optimizer.java:399)
at org.mozilla.javascript.optimizer.Optimizer.rewriteAsObjectChildren(Optimizer.java:409)
at org.mozilla.javascript.optimizer.Optimizer.rewriteForNumberVariables(Optimizer.java:399)
at org.mozilla.javascript.optimizer.Optimizer.rewriteAsObjectChildren(Optimizer.java:409)
at org.mozilla.javascript.optimizer.Optimizer.rewriteForNumberVariables(Optimizer.java:399)
at org.mozilla.javascript.optimizer.Optimizer.rewriteAsObjectChildren(Optimizer.java:409)

[midgleyc]

Two tests fail: regress-89443 and regress-98901, both with Stack Overflows. Unfortunately, when I run them alone (in Java 17) they both pass. Any idea why they might be failing on GitHub?

[midgleyc]

I rebased and the issue went away.

[tuchida]

Others look good. Thanks!

[tuchida]

Suggested change

	case Id_flat_map:
	return js_flat_map(cx, scope, thisObj, args);
	case Id_flatMap:
	return js_flatMap(cx, scope, thisObj, args);

I want the case to be the same as other method names.

rhino/src/org/mozilla/javascript/NativeArray.java

Lines 430 to 431 in 90d3b44

	case Id_lastIndexOf:
	return js_lastIndexOf(cx, scope, thisObj, args);

[gbrail]

Looks good. Thanks for working on this!