Deprecate "derive default"

Summary:
We can't remove the feature entirely, because it exists in the schema
in old DBs. So bump the Angle version and stop supporting it going
forwards, then we can remove it later.

Reviewed By: iamirzhan

Differential Revision: D68626170

fbshipit-source-id: 4189eea0c8b7b1e4f24565bdc325f084eb7455ea

glean/hs/Glean/Angle/Parser.y

@@ -14,6 +14,7 @@ import Control.Monad.Except
 import Data.ByteString (ByteString)
 import qualified Data.ByteString.Char8 as B
 import qualified Data.ByteString.Lazy.Char8 as LB
+import Data.Char
 import Data.Either (partitionEithers)
 import Data.List.NonEmpty (NonEmpty((:|)))
 import Data.Maybe
@@ -272,7 +273,7 @@ derivewhen :: { Schema.DeriveWhen }
 derivewhen
   : {- empty -}  { Schema.DeriveOnDemand }
   | 'stored'  { Schema.DerivedAndStored }
-  | 'default'  { Schema.DeriveIfEmpty }
+  | 'default'  {% ifVersionOrOlder (AngleVersion 11) $1 Schema.DeriveIfEmpty }
 
 derivedecl :: { Schema.SourceDecl }
 derivedecl
@@ -424,7 +425,7 @@ parseSchema bs = parseSchemaWithVersion ver rest
 
 stripAngleVersion :: ByteString -> (AngleVersion, ByteString)
 stripAngleVersion bs
-  | Just bs1 <- B.stripPrefix "version: " bs
+  | Just bs1 <- B.stripPrefix "version: " (B.dropWhile isSpace bs)
   , Just (ver, bs2) <- B.readInt bs1 = (Schema.AngleVersion ver, bs2)
   | otherwise = (latestAngleVersion, bs)
   -- if the header is omitted, assume we are using the latest version

glean/hs/Glean/Angle/Types.hs

@@ -679,12 +679,14 @@ newtype AngleVersion = AngleVersion Int
 --   - optional versions in `import`, `evolves`, inheritance
 -- version 11:
 --   - size primop
+-- version 12:
+--   - remove support for deriving default
 
 latestSupportedAngleVersion :: AngleVersion
 latestSupportedAngleVersion = AngleVersion 5
 
 latestAngleVersion :: AngleVersion
-latestAngleVersion = AngleVersion 11
+latestAngleVersion = AngleVersion 12
 
 -- -----------------------------------------------------------------------------
 -- Pretty-printing

glean/schema/source/VERSION

@@ -1,4 +1,4 @@
-version: 10
+version: 12
 # This tells the Angle parser which version of the syntax we're using.
 # NOTE: bump this version whenever we make a change to the syntax.
 # NOTE: also change latestAngleVersion in glean/hs/Glean/Angle/Types.hs

glean/test/tests/Schema/Basic.hs

@@ -460,6 +460,7 @@ backwardCompatDeriving = TestCase $
       schema_v1_file = root </> "schema1"
       schema_v1 =
         [s|
+          version: 11
           schema test.1 {
             predicate P : { a : string, b : nat }
             predicate Q : { p : P }
@@ -530,6 +531,7 @@ deriveDefault = TestCase $
       schema_v0_file = root </> "schema0"
       schema_v0 =
         [s|
+          version: 11
           schema test.1 {
             predicate P : { a : string, b : nat }
             predicate Q : { p : P }