Add delete function to Config_tree, add some tests for it.

3 files changed, 54 insertions, 5 deletions

diff --git a/src/config_tree.ml b/src/config_tree.ml
index b70a8bb..33af881 100644
--- a/src/config_tree.ml
+++ b/src/config_tree.ml
@@ -2,6 +2,7 @@ type value_behaviour = AddValue | ReplaceValue
 
 exception Duplicate_value
 exception Node_has_no_value
+exception No_such_value
 
 type config_node_data = {
     values: string list;
@@ -31,6 +32,11 @@ let add_value node path value =
         let values = values @ [value] in
         Vytree.update node path ({data with values=values})
 
+let delete_value node path value =
+    let data = Vytree.data_of_node @@ Vytree.get node path in
+    let values = Vylist.remove (fun x -> x = value) data.values in
+    Vytree.update node path {data with values=values}
+
 let set_value node path value behaviour =
     match behaviour with
     | AddValue -> add_value node path value
@@ -52,3 +58,16 @@ let get_value node path =
     match values with
     | [] -> raise Node_has_no_value
     | x :: _ -> x
+
+let delete node path value =
+    match value with
+    | Some v ->
+        (let values = get_values node path in
+        if Vylist.in_list values v then
+        (match values with
+        | [_] -> Vytree.delete node path
+        | _ -> delete_value node path v)
+        else raise No_such_value)
+    | None ->
+	Vytree.delete node path
+
diff --git a/src/config_tree.mli b/src/config_tree.mli
index 7ce505c..e4c91fc 100644
--- a/src/config_tree.mli
+++ b/src/config_tree.mli
@@ -16,6 +16,8 @@ val make : string -> t
 
 val set : t -> string list -> string -> value_behaviour -> t
 
+val delete : t -> string list -> string option -> t
+
 val get_values : t -> string list -> string list
 
 val get_value : t -> string list -> string
diff --git a/test/config_tree_test.ml b/test/config_tree_test.ml
index 58a95ad..516960d 100644
--- a/test/config_tree_test.ml
+++ b/test/config_tree_test.ml
@@ -1,18 +1,46 @@
 open OUnit2
 
 module VT = Vytree
-open Config_tree
+module CT = Config_tree
  
 let test_set_create_node test_ctxt =
-    let node = make "root" in
-    let node = set node ["foo"; "bar"] "baz" ReplaceValue in
-    let data = VT.get_data node ["foo"; "bar"] in
-    assert_equal data.values ["baz"]
+    let path = ["foo"; "bar"] in
+    let node = CT.make "root" in
+    let node = CT.set node path "baz" CT.ReplaceValue in
+    let values = CT.get_values node path in
+    assert_equal values ["baz"]
+
+(* Deleting just one of many values should keep all other values intact *)
+let test_delete_just_value test_ctxt =
+    let path = ["foo"; "bar"] in
+    let node = CT.make "root" in
+    let node = CT.set node path "baz" CT.AddValue in
+    let node = CT.set node path "quux" CT.AddValue in
+    let node = CT.delete node path (Some "quux") in
+    assert_equal (CT.get_values node path) ["baz"]
+
+(* Deleting the last value should delete the whole leaf *)
+let test_delete_last_value test_ctxt =
+    let path = ["foo"; "bar"] in
+    let node = CT.make "root" in
+    let node = CT.set node path "baz" CT.AddValue in
+    let node = CT.delete node path (Some "baz") in
+    assert_equal ((not (VT.exists node path)) && (VT.exists node ["foo"])) true
+
+(* Deleting a non-leaf node should delete the whole subtree *)
+let test_delete_subtree test_ctxt =
+    let path = ["foo"; "bar"] in
+    let node = CT.make "root" in
+    let node = CT.set node path "baz" CT.AddValue in
+    let node = CT.delete node path None in
+    assert_equal (VT.list_children node) []
 
 
 let suite =
     "VyConf config tree tests" >::: [
         "test_set_create_node" >:: test_set_create_node;
+        "test_delete_just_value" >:: test_delete_just_value;
+        "test_delete_last_value" >:: test_delete_last_value;
     ]
 
 let () =