Add tests for printing jkinds (#169)

Author: liam923

tests/test-dirs/type-enclosing/kinds.t

@@ -0,0 +1,100 @@
+Test that kinds get printed correctly.
+
+  $ type_enclosing () {
+  >   local filename=test.ml
+  >   cat > "$filename"
+  >   local pos="$1"
+  > 
+  >   local prev_output=""
+  >   local verbosity=0
+  >   while true; do
+  >     local current_output=$($MERLIN single type-enclosing -position "$pos" -verbosity "$verbosity" -filename "$filename" < "$filename" \
+  >       | revert-newlines | jq .value[0].type -r)
+  >     
+  >     # Check if current output matches previous output
+  >     if [ "$current_output" = "$prev_output" ]; then
+  >       break
+  >     else
+  >       echo "Verbosity $verbosity:"
+  >       echo "$current_output"
+  >       prev_output="$current_output"
+  >       verbosity=$((verbosity + 1))
+  >     fi
+  >   done
+  > }
+
+Abstract types
+  $ type_enclosing 2:11 <<EOF
+  > type t
+  > type foo = t
+  > EOF
+  Verbosity 0:
+  type t
+
+  $ type_enclosing 2:11 <<EOF
+  > type t : immutable_data
+  > type foo = t
+  > EOF
+  Verbosity 0:
+  type t : immutable_data
+
+Types with kinds (kinds, not jkinds)
+  $ type_enclosing 2:11 <<EOF
+  > type t = Foo of { mutable foo : int }
+  > type foo = t
+  > EOF
+  Verbosity 0:
+  type t = Foo of { mutable foo : int; }
+  Verbosity 1:
+  type t : mutable_data = Foo of { mutable foo : int; }
+
+  $ type_enclosing 3:17 <<EOF 
+  > type 'a t1 = { foo : 'a }
+  > type 'a t2 = 'a t1 = { foo : 'a }
+  > type foo = int t2
+  > EOF
+  Verbosity 0:
+  type 'a t2 = 'a t1 = { foo : 'a; }
+  Verbosity 1:
+  type 'a t2 : immutable_data with 'a = 'a t1 = { foo : 'a; }
+
+Non-Tconstr types
+  $ type_enclosing 2:11 <<EOF
+  > type t = int * string
+  > type foo = t
+  > EOF
+  Verbosity 0:
+  type t = int * string
+  Verbosity 1:
+  type t : immutable_data with int with string = int * string
+
+  $ type_enclosing 2:11 <<EOF
+  > type t = [\`Foo | \`Bar of int]
+  > type foo = t
+  > EOF
+  Verbosity 0:
+  type t = [ `Bar of int | `Foo ]
+  Verbosity 1:
+  type t : value mod non_float = [ `Bar of int | `Foo ]
+
+Module types
+# CR-someday: Make kinds get printed when verbosity is 1
+  $ type_enclosing 8:11 <<EOF
+  > module M = struct
+  >   type t_value
+  >   type t_immediate : immediate
+  >   type t_record = { foo : int }
+  >   type t_kind_and_manifest = t_record = { foo : int }
+  >   type t_tuple = int * string
+  > end
+  > module _ = M
+  > EOF
+  Verbosity 0:
+  sig
+    type t_value
+    type t_immediate : immediate
+    type t_record = { foo : int; }
+    type t_kind_and_manifest = t_record = { foo : int; }
+    type t_tuple = int * string
+  end
+