Add diagnostics working group

Author: oli-obk

README.md

@@ -61,6 +61,7 @@ Name                                                      | Status       | Short
 [Rustc pipelining](working-groups/pipelining/)            | Active       | Enable Cargo to invoke rustc in a pipelined fashion, speeding up crate graph compiles.             | [#t-compiler/wg-pipelining][pipelining-stream]
 [Polonius](working-groups/polonius/)                      | Active       | Exploring the integration of the "NLL 2.0"-like ["Polonius analysis"][Polonius] into rustc         | [#t-compiler/wg-polonius][polonius_stream]
 [Learning](working-groups/learning/)                      | Active       | Make the compiler easier to learn by ensuring that rustc-guide and api docs are "complete"         | [#t-compiler/wg-learning][learning_stream]
+[Diagnostics](working-groups/diagnostics/)                | Active       | Use crates.io crates for diagnostics rendering and make emitting diagnostics nicer.                | [#t-compiler/wg-diagnostics][diagnostics-stream]
 
 [nikomatsakis]: https://github.com/nikomatsakis
 [cramertj]: https://github.com/cramertj
@@ -74,6 +75,7 @@ Name                                                      | Status       | Short
 [Zoxc]: https://github.com/Zoxc
 [blitzerr]: https://github.com/blitzerr
 [oli-obk]: https://github.com/oli-obk
+[estebank]: https://github.com/estebank
 
 [Weekly, in Zulip]: #meeting-calendar
 [nll_stream]: https://rust-lang.zulipchat.com/#narrow/stream/122657-t-compiler.2Fwg-nll
@@ -91,6 +93,7 @@ Name                                                      | Status       | Short
 [polonius_stream]: https://rust-lang.zulipchat.com/#narrow/stream/186049-t-compiler.2Fwg-polonius
 [learning_stream]: https://rust-lang.zulipchat.com/#narrow/stream/196385-t-compiler.2Fwg-learning
 [Polonius]: https://github.com/rust-lang/polonius
+[diagnostics-stream]: https://rust-lang.zulipchat.com/#narrow/stream/147480-t-compiler.2Fwg-diagnostics
 
 ## Expert Map
 

working-groups/diagnostics/FAQ.md

@@ -0,0 +1,5 @@
+# Frequently Asked Questions (FAQ)
+
+If you have a question, feel free to file an issue or ask in the working group's Zulip stream.
+
+There are no FAQs so far. Please ask us more questions.

working-groups/diagnostics/NOTES.md

@@ -0,0 +1,3 @@
+# Diagnostics Meeting Notes
+This document will contain meeting notes from the diagnostics working group.
+

working-groups/diagnostics/README.md

@@ -0,0 +1,43 @@
+# Diagnostics Working Group
+![working group status: active][status]
+
+This working group aims to make rustc better at telling the user why the compiler isn't smart enough
+yet to understand their code.
+
+- **Leads:** [@oli-obk][oli-obk] [@estebank][estebank]
+- **Meeting Notes:** [All](NOTES.md)
+
+[status]: https://img.shields.io/badge/status-active-brightgreen.svg?style=for-the-badge
+
+## What is the goal of this working group?
+This working group aims to accomplish the following:
+
+- Make diagnostics emitting independent of the happy code path
+- Separate the diagnostics rendering from the compiler so it can be reused by others.
+
+# How can I get involved?
+If you are interested in getting involved in this working group, you should introduce yourself
+in the Zulip stream. You can be added to the GitHub and Zulip
+group for the working group if you are interested in being pinged when there are available tasks.
+
+- **Desired experience level:** Any
+- **Relevant repositories:** [`rust-lang/rust`][repo]
+    - https://github.com/rust-lang/rust/blob/master/src/libsyntax/json.rs
+    - https://github.com/rust-lang/rust/tree/master/src/librustc_errors
+    - https://github.com/rust-lang/rust/tree/master/src/librustc_lint
+    - https://crates.io/crates/annotate-snippets
+    - https://crates.io/crates/codemap-diagnostic
+- **Zulip stream:** [`#t-compiler/diagnostics`][zulip] on Zulip
+
+[repo]: https://github.com/rust-lang/rust
+[zulip]: https://rust-lang.zulipchat.com/#narrow/stream/147480-t-compiler.2Fwg-diagnostics
+
+## What if I don't have much time?
+If you don't have time to contribute code, consider setting up meetings and frequently pinging
+working group members on related issues to discuss or fix them.
+
+## Are there any resources so I can get up to speed?
+Not yet.
+
+## Do I need to attend any meetings?
+We don't have any meetings yet.