Merge #3727

3727: Introduce ra_proc_macro r=matklad a=edwin0cheng

This PR implemented:

1.  Reading dylib path of proc-macro crate from cargo check , similar to how `OUTDIR` is obtained.
2.  Added a new crate `ra_proc_macro` and implement the foot-work for reading result from external proc-macro expander. 
3. Added a struct `ProcMacroClient` , which will be responsible to the client side communication to the External process.



Co-authored-by: Edwin Cheng <[email protected]>

1 files changed, 9 insertions, 0 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 10ea55550..3bb1df05b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -928,6 +928,7 @@ dependencies = [
  "ra_cfg",
  "ra_prof",
  "ra_syntax",
+ "ra_tt",
  "relative-path",
  "rustc-hash",
  "salsa",
@@ -1082,6 +1083,13 @@ dependencies = [
 ]
 
 [[package]]
+name = "ra_proc_macro"
+version = "0.1.0"
+dependencies = [
+ "ra_tt",
+]
+
+[[package]]
 name = "ra_prof"
 version = "0.1.0"
 dependencies = [
@@ -1102,6 +1110,7 @@ dependencies = [
  "ra_cargo_watch",
  "ra_cfg",
  "ra_db",
+ "ra_proc_macro",
  "rustc-hash",
  "serde",
  "serde_json",