diff --git a/tests/test-dirs/locate/issue1915.t b/tests/test-dirs/locate/issue1915.t
new file mode 100644
index 000000000..f5481290f
--- /dev/null
+++ b/tests/test-dirs/locate/issue1915.t
@@ -0,0 +1,58 @@
+Testing the behavior of custom operators
+
+  $ cat >main.ml <<EOF
+  > let ( := ) v a = Printf.printf "%s = %d;\n" v a
+  > let () = "foo" := 3
+  > let () = ( := ) "foo"  3
+  > EOF
+
+  $ $MERLIN single locate -look-for ml -position 2:17 \
+  > -filename ./main.ml < ./main.ml | jq '.value'
+  "Not a valid identifier"
+
+  $ $MERLIN single locate -look-for ml -position 3:12 \
+  > -filename ./main.ml < ./main.ml | jq '.value'
+  "Not a valid identifier"
+
+Testing custom indexing operators
+
+  $ cat >main.ml <<EOF
+  > let (.%{;..}) a k = Printf.printf "%s.coeffRef(%d);\n" a k.(0)
+  > let (.%{ }) a k = Printf.printf "%s.coeffRef(%d);\n" a k
+  > let name = "baz"
+  > let () = name.%{2;4}
+  > let () = name.%{5}
+  > let () = ( .%{ } ) name 3
+  > EOF
+
+  $ $MERLIN single locate -look-for ml -position 4:15 \
+  > -filename ./main.ml < ./main.ml | jq '.value'
+  "Not in environment '%'"
+
+  $ $MERLIN single locate -look-for ml -position 4:16 \
+  > -filename ./main.ml < ./main.ml | jq '.value'
+  "Not a valid identifier"
+
+  $ $MERLIN single locate -look-for ml -position 5:15 \
+  > -filename ./main.ml < ./main.ml | jq '.value'
+  "Not in environment '%'"
+
+  $ $MERLIN single locate -look-for ml -position 5:15 \
+  > -filename ./main.ml < ./main.ml | jq '.value'
+  "Not in environment '%'"
+
+  $ $MERLIN single locate -look-for ml -position 5:16 \
+  > -filename ./main.ml < ./main.ml | jq '.value'
+  "Not a valid identifier"
+
+  $ $MERLIN single locate -look-for ml -position 6:13 \
+  > -filename ./main.ml < ./main.ml | jq '.value'
+  "Not in environment '%'"
+
+  $ $MERLIN single locate -look-for ml -position 6:14 \
+  > -filename ./main.ml < ./main.ml | jq '.value'
+  "Not a valid identifier"
+
+  $ $MERLIN single locate -look-for ml -position 6:15 \
+  > -filename ./main.ml < ./main.ml | jq '.value'
+  "Not a valid identifier"