[ parser ] Fix issue parsing unquote

CHANGELOG_NEXT.md

@@ -46,6 +46,9 @@ This CHANGELOG describes the merged but unreleased changes. Please see [CHANGELO
   environment variable adds to the "Package Search Paths." Functionally this is
   not a breaking change.
 
+* The compiler now parses `~x.fun` as unquoting `x` rather than `x.fun`
+  and `~(f 5).fun` as unquoting `(f 5)` rather than `(f 5).fun`.
+
 ### Backend changes
 
 #### RefC Backend

src/Idris/Parser.idr

@@ -631,7 +631,7 @@ mutual
                   decoratedSymbol fname "]"
                   pure ts
            pure (PQuoteDecl (boundToFC fname b) (collectDefs (concat b.val)))
-    <|> do b <- bounds (decoratedSymbol fname "~" *> simpleExpr fname indents)
+    <|> do b <- bounds (decoratedSymbol fname "~" *> simplerExpr fname indents)
            pure (PUnquote (boundToFC fname b) b.val)
     <|> do start <- bounds (symbol "(")
            bracketedExpr fname start indents

tests/idris2/error/perror031/Issue3251.idr

@@ -0,0 +1,19 @@
+import Language.Reflection
+
+(.fun) : Nat -> Nat
+
+x : TTImp
+
+f : Nat -> TTImp
+
+useX : TTImp
+useX = `(g (~x).fun)
+
+useX' : TTImp
+useX' = `(g ~x.fun)
+
+useFX : TTImp
+useFX = `(g (~(f 5)).fun)
+
+useFX' : TTImp
+useFX' = `(g ~(f 5).fun)

tests/idris2/error/perror031/expected

@@ -0,0 +1 @@
+1/1: Building Issue3251 (Issue3251.idr)

tests/idris2/error/perror031/run

@@ -0,0 +1,3 @@
+. ../../../testutils.sh
+
+check Issue3251.idr