• Part 3 uses functions added in ICU 64, so we need to bump the version requirement.
• Also remove a version check which is now true be default.

Add js::intl::NumberFormatFields containing the two methods:

• append: To append a number format field
• toArray: To construct the result Array object

The unitType argument for NumberFormatFields::toArray will be used in part 3.

Depends on D26717

• The new formatted-value API is still draft-only, so extra U_HIDE_DRAFT_API guards
  are currently needed.
• Also moves steps 4-5 of PartitionRelativeTimePattern to native code to reduce code
  duplication.

Depends on D26718

Can we land this?

There are some r+ patches which didn't land and no activity in this bug for 2 weeks.
:anba, could you have a look please?
For more information, please visit auto_nag documentation.

Try: https://treeherder.mozilla.org/#/jobs?repo=try&revision=d713ed65cd595c382a08381b9af068bd7e139a5d

Could not land due to uncommitted changes, please rebase.

All commits are now rebased to apply cleanly on inbound.

Pushed by ncsoregi@mozilla.com:
https://hg.mozilla.org/integration/autoland/rev/5109ce5a4b44
Part 1: Bump minimum required ICU version to 64.1. r=jwalden
https://hg.mozilla.org/integration/autoland/rev/f3a2031bde94
Part 2: Make it possible to reuse the number-formatter parts generator code. r=jwalden
https://hg.mozilla.org/integration/autoland/rev/953a2bd4220b
Part 3: Add support for "formatToParts" to Intl.RelativeTimeFormat. r=jwalden

Backed out 3 changesets for causing bustages in ICUStubs.h

Backout link: https://hg.mozilla.org/integration/autoland/rev/505173c26e1af4afcb7ee13a567a5ae4d8149dc7

Push with failures: https://treeherder.mozilla.org/#/jobs?repo=autoland&resultStatus=testfailed%2Cbusted%2Cexception&tochange=505173c26e1af4afcb7ee13a567a5ae4d8149dc7&fromchange=953a2bd4220bec9ea10512536aa06cf55288a972&selectedJob=255439570

Failure log: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=255439570&repo=autoland&lineNumber=2816

[task 2019-07-09T08:56:37.845Z] Running CARGO_PKG_DESCRIPTION='Rust bindings for libclang.' CARGO_PKG_VERSION_PRE= CARGO_PKG_VERSION_MINOR=28 CARGO_PKG_REPOSITORY='https://github.com/KyleMayes/clang-sys' LD_LIBRARY_PATH='/builds/worker/workspace/obj-haz-shell/release/deps:/builds/worker/workspace/rustc/lib:/builds/worker/workspace/gcc/lib64' CARGO_MANIFEST_DIR=/builds/worker/checkouts/gecko/third_party/rust/clang-sys CARGO_PKG_NAME=clang-sys CARGO=/builds/worker/workspace/rustc/bin/cargo CARGO_PKG_HOMEPAGE= CARGO_PKG_VERSION_PATCH=0 CARGO_PKG_VERSION=0.28.0 CARGO_PKG_AUTHORS='Kyle Mayes <kyle@mayeses.com>' CARGO_PKG_VERSION_MAJOR=0 /builds/worker/workspace/rustc/bin/rustc --crate-name build_script_build /builds/worker/checkouts/gecko/third_party/rust/clang-sys/build.rs --color never --crate-type bin --emit=dep-info,link -C opt-level=2 -C codegen-units=1 --cfg 'feature="clang_6_0"' --cfg 'feature="gte_clang_3_6"' --cfg 'feature="gte_clang_3_7"' --cfg 'feature="gte_clang_3_8"' --cfg 'feature="gte_clang_3_9"' --cfg 'feature="gte_clang_4_0"' --cfg 'feature="gte_clang_5_0"' --cfg 'feature="gte_clang_6_0"' --cfg 'feature="libloading"' --cfg 'feature="runtime"' -C metadata=9d393b86f2778e0b -C extra-filename=-9d393b86f2778e0b --out-dir /builds/worker/workspace/obj-haz-shell/release/build/clang-sys-9d393b86f2778e0b -C linker=/builds/worker/checkouts/gecko/build/cargo-linker -L dependency=/builds/worker/workspace/obj-haz-shell/release/deps --extern glob=/builds/worker/workspace/obj-haz-shell/release/deps/libglob-ad84f23146e28cf1.rlib --cap-lints warn
[task 2019-07-09T08:56:38.090Z] In file included from /builds/worker/checkouts/gecko/js/src/builtin/intl/CommonFunctions.h:17:0,
[task 2019-07-09T08:56:38.090Z] from /builds/worker/checkouts/gecko/js/src/builtin/intl/DateTimeFormat.h:12,
[task 2019-07-09T08:56:38.090Z] from /builds/worker/checkouts/gecko/js/src/vm/SelfHosting.cpp:25,
[task 2019-07-09T08:56:38.090Z] from /builds/worker/workspace/obj-haz-shell/js/src/Unified_cpp_js_src19.cpp:47:
[task 2019-07-09T08:56:38.090Z] /builds/worker/checkouts/gecko/js/src/builtin/intl/ICUStubs.h:712:8: error: 'UConstrainedFieldPosition' does not name a type
[task 2019-07-09T08:56:38.090Z] inline UConstrainedFieldPosition* ucfpos_open(UErrorCode* status) {
[task 2019-07-09T08:56:38.090Z] ^~~~~~~~~~~~~~~~~~~~~~~~~
[task 2019-07-09T08:56:38.090Z] /builds/worker/checkouts/gecko/js/src/builtin/intl/ICUStubs.h:716:26: error: variable or field 'ucfpos_close' declared void
[task 2019-07-09T08:56:38.090Z] inline void ucfpos_close(UConstrainedFieldPosition* ucfpos) {
[task 2019-07-09T08:56:38.091Z] ^~~~~~~~~~~~~~~~~~~~~~~~~
[task 2019-07-09T08:56:38.091Z] /builds/worker/checkouts/gecko/js/src/builtin/intl/ICUStubs.h:716:26: error: 'UConstrainedFieldPosition' was not declared in this scope
[task 2019-07-09T08:56:38.091Z] /builds/worker/checkouts/gecko/js/src/builtin/intl/ICUStubs.h:716:53: error: 'ucfpos' was not declared in this scope
[task 2019-07-09T08:56:38.091Z] inline void ucfpos_close(UConstrainedFieldPosition* ucfpos) {
[task 2019-07-09T08:56:38.091Z] ^~~~~~
[task 2019-07-09T08:56:38.091Z] In file included from /builds/worker/checkouts/gecko/js/src/builtin/intl/NumberFormat.h:12:0,
[task 2019-07-09T08:56:38.091Z] from /builds/worker/checkouts/gecko/js/src/vm/SelfHosting.cpp:27,
[task 2019-07-09T08:56:38.092Z] from /builds/worker/workspace/obj-haz-shell/js/src/Unified_cpp_js_src19.cpp:47:
[task 2019-07-09T08:56:38.092Z] /builds/worker/workspace/obj-haz-shell/dist/system_wrappers/stdint.h:2:37: error: expected declaration before end of line
...

Updated to add the missing UConstrainedFieldPosition declaration.

Try: https://treeherder.mozilla.org/#/jobs?repo=try&revision=e3281317677a0370478c5b23fd75aa7f1f6523cd

Pushed by archaeopteryx@coole-files.de:
https://hg.mozilla.org/integration/autoland/rev/bf94fe26b0e3
Part 1: Bump minimum required ICU version to 64.1. r=jwalden
https://hg.mozilla.org/integration/autoland/rev/e65dd4b9b049
Part 2: Make it possible to reuse the number-formatter parts generator code. r=jwalden
https://hg.mozilla.org/integration/autoland/rev/66cbc40a0aac
Part 3: Add support for "formatToParts" to Intl.RelativeTimeFormat. r=jwalden

https://hg.mozilla.org/mozilla-central/rev/bf94fe26b0e3
https://hg.mozilla.org/mozilla-central/rev/e65dd4b9b049
https://hg.mozilla.org/mozilla-central/rev/66cbc40a0aac

Doc updates:

• Fx 70 release notes: https://developer.mozilla.org/en-US/docs/Mozilla/Firefox/Releases/70
• Reference page: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RelativeTimeFormat/formatToParts (originally authored by Romulo Cintra)
• Compat data: https://github.com/mdn/browser-compat-data/pull/4717
• Interactive exmaple: https://github.com/mdn/interactive-examples/pull/1300

I think this has been reviewed sufficiently. Let me know if you have additional feedback.