From 008a9c3e3709f3eec4e28f305664c99c7f3d635c Mon Sep 17 00:00:00 2001
From: Gabriel Gonzalez <Gabriel439@gmail.com>
Date: Mon, 11 Nov 2019 12:43:29 -0800
Subject: [PATCH] Fix parser for expressions with nested annotations (#1527)

Fixes https://github.com/dhall-lang/dhall-haskell/issues/1467

We now no longer replace an annotation if one was already present
---
 dhall/src/Dhall/Parser/Expression.hs       | 6 +++---
 dhall/tests/format/nestedAnnotationA.dhall | 1 +
 dhall/tests/format/nestedAnnotationB.dhall | 1 +
 3 files changed, 5 insertions(+), 3 deletions(-)
 create mode 100644 dhall/tests/format/nestedAnnotationA.dhall
 create mode 100644 dhall/tests/format/nestedAnnotationB.dhall

diff --git a/dhall/src/Dhall/Parser/Expression.hs b/dhall/src/Dhall/Parser/Expression.hs
index 86ab986..43387ee 100644
--- a/dhall/src/Dhall/Parser/Expression.hs
+++ b/dhall/src/Dhall/Parser/Expression.hs
@@ -273,11 +273,11 @@ parsers embedded = Parsers {..}
                     nonemptyWhitespace
                     b <- expression
                     case shallowDenote a of
-                        ListLit _ [] ->
+                        ListLit Nothing [] ->
                             return (ListLit (Just b) [])
-                        Merge c d _ ->
+                        Merge c d Nothing ->
                             return (Merge c d (Just b))
-                        ToMap c _ ->
+                        ToMap c Nothing ->
                             return (ToMap c (Just b))
                         _ -> return (Annot a b)
 
diff --git a/dhall/tests/format/nestedAnnotationA.dhall b/dhall/tests/format/nestedAnnotationA.dhall
new file mode 100644
index 0000000..c8dc65f
--- /dev/null
+++ b/dhall/tests/format/nestedAnnotationA.dhall
@@ -0,0 +1 @@
+([] : a) : b
diff --git a/dhall/tests/format/nestedAnnotationB.dhall b/dhall/tests/format/nestedAnnotationB.dhall
new file mode 100644
index 0000000..c8dc65f
--- /dev/null
+++ b/dhall/tests/format/nestedAnnotationB.dhall
@@ -0,0 +1 @@
+([] : a) : b