Merge branch 'egil/maps-api-additions/PR-1025/OTP-13522'

* egil/maps-api-additions/PR-1025/OTP-13522:
  stdlib: Document maps:update_with/3,4
  stdlib: Add tests for maps:update_with/3,4
  stdlib: Add maps:update_with/3,4
  erts: Add tests for maps:take/2
  stdlib: Document maps:take/2
  erts: Add BIF maps:take/2

8 files changed, 275 insertions, 49 deletions

diff --git a/erts/emulator/beam/bif.tab b/erts/emulator/beam/bif.tab
index 58cd31cee9..872f0f9b2a 100644
--- a/erts/emulator/beam/bif.tab
+++ b/erts/emulator/beam/bif.tab
@@ -652,6 +652,8 @@ bif erts_debug:size_shared/1
 bif erts_debug:copy_shared/1
 bif erlang:has_prepared_code_on_load/1
 
+bif maps:take/2
+
 #
 # Obsolete
 #
diff --git a/erts/emulator/beam/erl_map.c b/erts/emulator/beam/erl_map.c
index 03a96cb00a..8efc983f04 100644
--- a/erts/emulator/beam/erl_map.c
+++ b/erts/emulator/beam/erl_map.c
@@ -54,6 +54,7 @@
  * - maps:new/0
  * - maps:put/3
  * - maps:remove/2
+ * - maps:take/2
  * - maps:to_list/1
  * - maps:update/3
  * - maps:values/1
@@ -93,7 +94,7 @@ static Uint hashmap_subtree_size(Eterm node);
 static Eterm hashmap_to_list(Process *p, Eterm map);
 static Eterm hashmap_keys(Process *p, Eterm map);
 static Eterm hashmap_values(Process *p, Eterm map);
-static Eterm hashmap_delete(Process *p, Uint32 hx, Eterm key, Eterm node);
+static Eterm hashmap_delete(Process *p, Uint32 hx, Eterm key, Eterm node, Eterm *value);
 static Eterm flatmap_from_validated_list(Process *p, Eterm list, Uint size);
 static Eterm hashmap_from_validated_list(Process *p, Eterm list, Uint size);
 static Eterm hashmap_from_unsorted_array(ErtsHeapFactory*, hxnode_t *hxns, Uint n, int reject_dupkeys);
@@ -1521,10 +1522,45 @@ BIF_RETTYPE maps_put_3(BIF_ALIST_3) {
     BIF_ERROR(BIF_P, BADMAP);
 }
 
-/* maps:remove/3 */
+/* maps:take/2 */
 
-int erts_maps_remove(Process *p, Eterm key, Eterm map, Eterm *res) {
+BIF_RETTYPE maps_take_2(BIF_ALIST_2) {
+    if (is_map(BIF_ARG_2)) {
+        Eterm res, map, val;
+        if (erts_maps_take(BIF_P, BIF_ARG_1, BIF_ARG_2, &map, &val)) {
+            Eterm *hp = HAlloc(BIF_P, 3);
+            res   = make_tuple(hp);
+            *hp++ = make_arityval(2);
+            *hp++ = val;
+            *hp++ = map;
+            BIF_RET(res);
+        }
+        BIF_RET(am_error);
+    }
+    BIF_P->fvalue = BIF_ARG_2;
+    BIF_ERROR(BIF_P, BADMAP);
+}
+
+/* maps:remove/2 */
+
+BIF_RETTYPE maps_remove_2(BIF_ALIST_2) {
+    if (is_map(BIF_ARG_2)) {
+        Eterm res;
+        (void) erts_maps_take(BIF_P, BIF_ARG_1, BIF_ARG_2, &res, NULL);
+        BIF_RET(res);
+    }
+    BIF_P->fvalue = BIF_ARG_2;
+    BIF_ERROR(BIF_P, BADMAP);
+}
+
+/* erts_maps_take
+ * return 1 if key is found, otherwise 0
+ * If the key is not found res (output map) will be map (input map)
+ */
+int erts_maps_take(Process *p, Eterm key, Eterm map,
+                   Eterm *res, Eterm *value) {
     Uint32 hx;
+    Eterm ret;
     if (is_flatmap(map)) {
 	Sint n;
 	Uint need;
@@ -1537,7 +1573,7 @@ int erts_maps_remove(Process *p, Eterm key, Eterm map, Eterm *res) {
 
 	if (n == 0) {
 	    *res = map;
-	    return 1;
+	    return 0;
 	}
 
 	ks = flatmap_get_keys(mp);
@@ -1564,6 +1600,7 @@ int erts_maps_remove(Process *p, Eterm key, Eterm map, Eterm *res) {
 	if (is_immed(key)) {
 	    while (1) {
 		if (*ks == key) {
+                    if (value) *value = *vs;
 		    goto found_key;
 		} else if (--n) {
 		    *mhp++ = *vs++;
@@ -1574,6 +1611,7 @@ int erts_maps_remove(Process *p, Eterm key, Eterm map, Eterm *res) {
 	} else {
 	    while(1) {
 		if (EQ(*ks, key)) {
+                    if (value) *value = *vs;
 		    goto found_key;
 		} else if (--n) {
 		    *mhp++ = *vs++;
@@ -1589,7 +1627,7 @@ int erts_maps_remove(Process *p, Eterm key, Eterm map, Eterm *res) {
 	HRelease(p, hp_start + need, hp_start);
 
 	*res = map;
-	return 1;
+	return 0;
 
 found_key:
 	/* Copy rest of keys and values */
@@ -1601,19 +1639,13 @@ found_key:
     }
     ASSERT(is_hashmap(map));
     hx = hashmap_make_hash(key);
-    *res = hashmap_delete(p, hx, key, map);
-    return 1;
-}
-
-BIF_RETTYPE maps_remove_2(BIF_ALIST_2) {
-    if (is_map(BIF_ARG_2)) {
-	Eterm res;
-	if (erts_maps_remove(BIF_P, BIF_ARG_1, BIF_ARG_2, &res)) {
-	    BIF_RET(res);
-	}
+    ret = hashmap_delete(p, hx, key, map, value);
+    if (is_value(ret)) {
+        *res = ret;
+        return 1;
     }
-    BIF_P->fvalue = BIF_ARG_2;
-    BIF_ERROR(BIF_P, BADMAP);
+    *res = map;
+    return 0;
 }
 
 int erts_maps_update(Process *p, Eterm key, Eterm value, Eterm map, Eterm *res) {
@@ -2322,7 +2354,8 @@ static Eterm hashmap_values(Process* p, Eterm node) {
     return res;
 }
 
-static Eterm hashmap_delete(Process *p, Uint32 hx, Eterm key, Eterm map) {
+static Eterm hashmap_delete(Process *p, Uint32 hx, Eterm key,
+                            Eterm map, Eterm *value) {
     Eterm *hp = NULL, *nhp = NULL, *hp_end = NULL;
     Eterm *ptr;
     Eterm hdr, res = map, node = map;
@@ -2337,8 +2370,12 @@ static Eterm hashmap_delete(Process *p, Uint32 hx, Eterm key, Eterm map) {
 	switch(primary_tag(node)) {
 	    case TAG_PRIMARY_LIST:
 		if (EQ(CAR(list_val(node)), key)) {
+                    if (value) {
+                        *value = CDR(list_val(node));
+                    }
 		    goto unroll;
 		}
+                res = THE_NON_VALUE;
 		goto not_found;
 	    case TAG_PRIMARY_BOXED:
 		ptr = boxed_val(node);
@@ -2365,6 +2402,7 @@ static Eterm hashmap_delete(Process *p, Uint32 hx, Eterm key, Eterm map) {
                             n    = hashmap_bitcount(hval);
                         } else {
                             /* not occupied */
+                            res = THE_NON_VALUE;
                             goto not_found;
                         }
 
@@ -2394,6 +2432,7 @@ static Eterm hashmap_delete(Process *p, Uint32 hx, Eterm key, Eterm map) {
 			    break;
 			}
 			/* not occupied */
+                        res = THE_NON_VALUE;
 			goto not_found;
 		    default:
 			erts_exit(ERTS_ERROR_EXIT, "bad header tag %ld\r\n", hdr & _HEADER_MAP_SUBTAG_MASK);
diff --git a/erts/emulator/beam/erl_map.h b/erts/emulator/beam/erl_map.h
index 7af9100906..8b5c9582ba 100644
--- a/erts/emulator/beam/erl_map.h
+++ b/erts/emulator/beam/erl_map.h
@@ -82,6 +82,7 @@ struct ErtsEStack_;
 Eterm  erts_maps_put(Process *p, Eterm key, Eterm value, Eterm map);
 int    erts_maps_update(Process *p, Eterm key, Eterm value, Eterm map, Eterm *res);
 int    erts_maps_remove(Process *p, Eterm key, Eterm map, Eterm *res);
+int    erts_maps_take(Process *p, Eterm key, Eterm map, Eterm *res, Eterm *value);
 
 Eterm  erts_hashmap_insert(Process *p, Uint32 hx, Eterm key, Eterm value,
 			   Eterm node, int is_update);
diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c
index 73c0eb8eba..24e72cc949 100644
--- a/erts/emulator/beam/erl_nif.c
+++ b/erts/emulator/beam/erl_nif.c
@@ -2443,14 +2443,13 @@ int enif_make_map_remove(ErlNifEnv* env,
 			 Eterm key,
 			 Eterm *map_out)
 {
-    int res;
     if (!is_map(map_in)) {
 	return 0;
     }
     flush_env(env);
-    res = erts_maps_remove(env->proc, key, map_in, map_out);
+    (void) erts_maps_take(env->proc, key, map_in, map_out, NULL);
     cache_env(env);
-    return res;
+    return 1;
 }
 
 int enif_map_iterator_create(ErlNifEnv *env,
diff --git a/erts/emulator/test/map_SUITE.erl b/erts/emulator/test/map_SUITE.erl
index 956b82335c..b3870f0313 100644
--- a/erts/emulator/test/map_SUITE.erl
+++ b/erts/emulator/test/map_SUITE.erl
@@ -48,6 +48,7 @@
          t_bif_map_new/1,
          t_bif_map_put/1,
          t_bif_map_remove/1,
+         t_bif_map_take/1, t_bif_map_take_large/1,
          t_bif_map_update/1,
          t_bif_map_values/1,
          t_bif_map_to_list/1,
@@ -112,7 +113,9 @@ all() -> [t_build_and_match_literals, t_build_and_match_literals_large,
           t_bif_map_get,t_bif_map_find,t_bif_map_is_key,
           t_bif_map_keys, t_bif_map_merge, t_bif_map_new,
           t_bif_map_put,
-          t_bif_map_remove, t_bif_map_update,
+          t_bif_map_remove,
+          t_bif_map_take, t_bif_map_take_large,
+          t_bif_map_update,
           t_bif_map_values,
           t_bif_map_to_list, t_bif_map_from_list,
 
@@ -1970,7 +1973,7 @@ t_bif_map_remove(Config) when is_list(Config) ->
     0  = erlang:map_size(maps:remove(some_key, #{})),
 
     M0 = #{ "hi" => "hello", int => 3, <<"key">> => <<"value">>,
-	4 => number, 18446744073709551629 => wat},
+            4 => number, 18446744073709551629 => wat},
 
     M1 = maps:remove("hi", M0),
     true = is_members([4,18446744073709551629,int,<<"key">>],maps:keys(M1)),
@@ -1999,10 +2002,71 @@ t_bif_map_remove(Config) when is_list(Config) ->
 
     %% error case
     do_badmap(fun(T) ->
-		      {'EXIT',{{badmap,T},[{maps,remove,_,_}|_]}} =
-	(catch maps:remove(a, T))
+		      {'EXIT',{{badmap,T},[{maps,remove,_,_}|_]}} = (catch maps:remove(a, T))
 	      end),
-     ok.
+    ok.
+
+t_bif_map_take(Config) when is_list(Config) ->
+    error = maps:take(some_key, #{}),
+
+    M0 = #{ "hi" => "hello", int => 3, <<"key">> => <<"value">>,
+            4 => number, 18446744073709551629 => wat},
+
+    5 = maps:size(M0),
+    {"hello", M1} = maps:take("hi", M0),
+    true = is_members([4,18446744073709551629,int,<<"key">>],maps:keys(M1)),
+    true = is_members([number,wat,3,<<"value">>],maps:values(M1)),
+    error = maps:take("hi", M1),
+    4 = maps:size(M1),
+
+    {3, M2} = maps:take(int, M1),
+    true = is_members([4,18446744073709551629,<<"key">>],maps:keys(M2)),
+    true = is_members([number,wat,<<"value">>],maps:values(M2)),
+    error = maps:take(int, M2),
+    3 = maps:size(M2),
+
+    {<<"value">>,M3} = maps:take(<<"key">>, M2),
+    true = is_members([4,18446744073709551629],maps:keys(M3)),
+    true = is_members([number,wat],maps:values(M3)),
+    error = maps:take(<<"key">>, M3),
+    2 = maps:size(M3),
+
+    {wat,M4} = maps:take(18446744073709551629, M3),
+    true = is_members([4],maps:keys(M4)),
+    true = is_members([number],maps:values(M4)),
+    error = maps:take(18446744073709551629, M4),
+    1 = maps:size(M4),
+
+    {number,M5} = maps:take(4, M4),
+    [] = maps:keys(M5),
+    [] = maps:values(M5),
+    error = maps:take(4, M5),
+    0 = maps:size(M5),
+
+    {wat,#{ "hi" := "hello", int := 3, 4 := number, <<"key">> := <<"value">>}} = maps:take(18446744073709551629,M0),
+
+    %% error case
+    do_badmap(fun(T) ->
+		      {'EXIT',{{badmap,T},[{maps,take,_,_}|_]}} = (catch maps:take(a, T))
+	      end),
+    ok.
+
+t_bif_map_take_large(Config) when is_list(Config) ->
+    KVs = [{{erlang:md5(<<I:64>>),I}, I}|| I <- lists:seq(1,500)],
+    M0 = maps:from_list(KVs),
+    ok = bif_map_take_all(KVs, M0),
+    ok.
+
+bif_map_take_all([], M0) ->
+    0 = maps:size(M0),
+    ok;
+bif_map_take_all([{K,V}|KVs],M0) ->
+    {ok,V} = maps:find(K,M0),
+    {V,M1} = maps:take(K,M0),
+    error  = maps:find(K,M1),
+    error  = maps:take(K,M1),
+    bif_map_take_all(KVs,M1).
+
 
 t_bif_map_update(Config) when is_list(Config) ->
     M0 = #{ "hi" => "hello", int => 3, <<"key">> => <<"value">>,
diff --git a/lib/stdlib/doc/src/maps.xml b/lib/stdlib/doc/src/maps.xml
index 0f58f19421..bf45461e2b 100644
--- a/lib/stdlib/doc/src/maps.xml
+++ b/lib/stdlib/doc/src/maps.xml
@@ -301,6 +301,30 @@ false</code>
 		</func>
 
 		<func>
+			<name name="take" arity="2"/>
+			<fsummary></fsummary>
+			<desc>
+				<p>
+					The function removes the <c><anno>Key</anno></c>, if it exists, and its associated value from
+                    <c><anno>Map1</anno></c> and returns a tuple with the removed <c><anno>Value</anno></c> and
+                    the new map <c><anno>Map2</anno></c> without key <c><anno>Key</anno></c>.
+                    If the key does not exist <c>error</c> is returned.
+				</p>
+				<p>
+					The call will fail with a <c>{badmap,Map}</c> exception if <c><anno>Map1</anno></c> is not a map.
+				</p>
+				<p>Example:</p>
+				<code type="none">
+> Map = #{"a" => "hello", "b" => "world"}.
+#{"a" => "hello", "b" => "world"}
+> maps:take("a",Map).
+{"hello",#{"b" => "world"}}
+> maps:take("does not exist",Map).
+error</code>
+			</desc>
+		</func>
+
+		<func>
 			<name name="size" arity="1"/>
 			<fsummary></fsummary>
 			<desc>
@@ -357,6 +381,42 @@ false</code>
 			</desc>
 		</func>
 
+        <func>
+            <name name="update_with" arity="3"/>
+            <fsummary></fsummary>
+            <desc>
+                <p>Update a value in a <c><anno>Map1</anno></c> associated with <c><anno>Key</anno></c> by
+                    calling <c><anno>Fun</anno></c> on the old value to get a new value. An exception
+                    <c>{badkey,<anno>Key</anno>}</c> is generated if
+                    <c><anno>Key</anno></c> is not present in the map.</p>
+            <p>Example:</p>
+            <code type="none">
+> Map = #{"counter" => 1},
+  Fun = fun(V) -> V + 1 end,
+  maps:update_with("counter",Fun,Map).
+#{"counter" => 2}</code>
+			</desc>
+        </func>
+
+        <func>
+            <name name="update_with" arity="4"/>
+            <fsummary></fsummary>
+            <desc>
+                <p>Update a value in a <c><anno>Map1</anno></c> associated with <c><anno>Key</anno></c> by
+                    calling <c><anno>Fun</anno></c> on the old value to get a new value.
+                    If <c><anno>Key</anno></c> is not present
+                    in <c><anno>Map1</anno></c> then <c><anno>Init</anno></c> will be associated with
+                    <c><anno>Key</anno></c>.
+                </p>
+                <p>Example:</p>
+                <code type="none">
+> Map = #{"counter" => 1},
+  Fun = fun(V) -> V + 1 end,
+  maps:update_with("new counter",Fun,42,Map).
+#{"counter" => 1,"new counter" => 42}</code>
+            </desc>
+        </func>
+
 		<func>
 			<name name="values" arity="1"/>
 			<fsummary></fsummary>
diff --git a/lib/stdlib/src/maps.erl b/lib/stdlib/src/maps.erl
index a52928f77f..ba9ad4f549 100644
--- a/lib/stdlib/src/maps.erl
+++ b/lib/stdlib/src/maps.erl
@@ -20,15 +20,15 @@
 
 -module(maps).
 
--export([get/3,filter/2,fold/3, map/2,
-         size/1,
+-export([get/3, filter/2,fold/3,
+         map/2, size/1,
+         update_with/3, update_with/4,
          without/2, with/2]).
 
-
-%%% BIFs
+%% BIFs
 -export([get/2, find/2, from_list/1,
          is_key/2, keys/1, merge/2,
-         new/0, put/3, remove/2,
+         new/0, put/3, remove/2, take/2,
          to_list/1, update/3, values/1]).
 
 -spec get(Key,Map) -> Value when
@@ -102,6 +102,13 @@ put(_,_,_) -> erlang:nif_error(undef).
 
 remove(_,_) -> erlang:nif_error(undef).
 
+-spec take(Key,Map1) -> {Value,Map2} | error when
+    Key :: term(),
+    Map1 :: map(),
+    Value :: term(),
+    Map2 :: map().
+
+take(_,_) -> erlang:nif_error(undef).
 
 -spec to_list(Map) -> [{Key,Value}] when
     Map :: map(),
@@ -127,8 +134,40 @@ update(_,_,_) -> erlang:nif_error(undef).
 
 values(_) -> erlang:nif_error(undef).
 
+%% End of BIFs
+
+-spec update_with(Key,Fun,Map1) -> Map2 when
+      Key :: term(),
+      Map1 :: map(),
+      Map2 :: map(),
+      Fun :: fun((Value1 :: term()) -> Value2 :: term()).
+
+update_with(Key,Fun,Map) when is_function(Fun,1), is_map(Map) ->
+    try maps:get(Key,Map) of
+        Val -> maps:update(Key,Fun(Val),Map)
+    catch
+        error:{badkey,_} ->
+            erlang:error({badkey,Key},[Key,Fun,Map])
+    end;
+update_with(Key,Fun,Map) ->
+    erlang:error(error_type(Map),[Key,Fun,Map]).
+
+
+-spec update_with(Key,Fun,Init,Map1) -> Map2 when
+      Key :: term(),
+      Map1 :: Map1,
+      Map2 :: Map2,
+      Fun :: fun((Value1 :: term()) -> Value2 :: term()),
+      Init :: term().
+
+update_with(Key,Fun,Init,Map) when is_function(Fun,1), is_map(Map) ->
+    case maps:find(Key,Map) of
+        {ok,Val} -> maps:update(Key,Fun(Val),Map);
+        error -> maps:put(Key,Init,Map)
+    end;
+update_with(Key,Fun,Init,Map) ->
+    erlang:error(error_type(Map),[Key,Fun,Init,Map]).
 
-%%% End of BIFs
 
 -spec get(Key, Map, Default) -> Value | Default when
         Key :: term(),
diff --git a/lib/stdlib/test/maps_SUITE.erl b/lib/stdlib/test/maps_SUITE.erl
index 8b3a8d7ae2..42e669a799 100644
--- a/lib/stdlib/test/maps_SUITE.erl
+++ b/lib/stdlib/test/maps_SUITE.erl
@@ -25,15 +25,10 @@
 
 -include_lib("common_test/include/ct.hrl").
 
-%% Test server specific exports
--export([all/0]).
--export([suite/0]).
--export([init_per_suite/1]).
--export([end_per_suite/1]).
--export([init_per_testcase/2]).
--export([end_per_testcase/2]).
-
--export([t_get_3/1, t_filter_2/1,
+-export([all/0, suite/0]).
+
+-export([t_update_with_3/1, t_update_with_4/1,
+         t_get_3/1, t_filter_2/1,
          t_fold_3/1,t_map_2/1,t_size_1/1,
          t_with_2/1,t_without_2/1]).
 
@@ -41,29 +36,56 @@
 %%-define(badarg(F,Args), {'EXIT', {badarg, [{maps,F,Args,_}|_]}}).
 %% silly broken hipe
 -define(badmap(V,F,_Args), {'EXIT', {{badmap,V}, [{maps,F,_,_}|_]}}).
+-define(badkey(K,F,_Args), {'EXIT', {{badkey,K}, [{maps,F,_,_}|_]}}).
 -define(badarg(F,_Args), {'EXIT', {badarg, [{maps,F,_,_}|_]}}).
 
 suite() ->
-    [{ct_hooks, [ts_install_cth]},
+    [{ct_hooks,[ts_install_cth]},
      {timetrap,{minutes,1}}].
 
 all() ->
-    [t_get_3,t_filter_2,
+    [t_update_with_3,t_update_with_4,
+     t_get_3,t_filter_2,
      t_fold_3,t_map_2,t_size_1,
      t_with_2,t_without_2].
 
-init_per_suite(Config) ->
-    Config.
+t_update_with_3(Config) when is_list(Config) ->
+    V1 = value1,
+    V2 = <<"value2">>,
+    V3 = "value3",
+    Map = #{ key1 => V1, key2 => V2, "key3" => V3 },
+    Fun = fun(V) -> [V,V,{V,V}] end,
+
+    #{ key1 := [V1,V1,{V1,V1}] } = maps:update_with(key1,Fun,Map),
+    #{ key2 := [V2,V2,{V2,V2}] } = maps:update_with(key2,Fun,Map),
+    #{ "key3" := [V3,V3,{V3,V3}] } = maps:update_with("key3",Fun,Map),
 
-end_per_suite(_Config) ->
+    %% error case
+    ?badmap(b,update_with,[[a,b],a,b]) = (catch maps:update_with([a,b],id(a),b)),
+    ?badarg(update_with,[[a,b],a,#{}]) = (catch maps:update_with([a,b],id(a),#{})),
+    ?badkey([a,b],update_with,[[a,b],Fun,#{}]) = (catch maps:update_with([a,b],Fun,#{})),
     ok.
 
-init_per_testcase(_Case, Config) ->
-    Config.
+t_update_with_4(Config) when is_list(Config) ->
+    V1 = value1,
+    V2 = <<"value2">>,
+    V3 = "value3",
+    Map = #{ key1 => V1, key2 => V2, "key3" => V3 },
+    Fun = fun(V) -> [V,V,{V,V}] end,
+    Init = 3,
+
+    #{ key1 := [V1,V1,{V1,V1}] } = maps:update_with(key1,Fun,Init,Map),
+    #{ key2 := [V2,V2,{V2,V2}] } = maps:update_with(key2,Fun,Init,Map),
+    #{ "key3" := [V3,V3,{V3,V3}] } = maps:update_with("key3",Fun,Init,Map),
 
-end_per_testcase(_Case, _Config) ->
+    #{ key3 := Init } = maps:update_with(key3,Fun,Init,Map),
+
+    %% error case
+    ?badmap(b,update_with,[[a,b],a,b]) = (catch maps:update_with([a,b],id(a),b)),
+    ?badarg(update_with,[[a,b],a,#{}]) = (catch maps:update_with([a,b],id(a),#{})),
     ok.
 
+
 t_get_3(Config) when is_list(Config) ->
     Map = #{ key1 => value1, key2 => value2 },
     DefaultValue = "Default value",