update algorithm

index.bs

@@ -2054,15 +2054,11 @@ The [=remote end steps=] with |session| and |command parameters| are:
 
    1. Let |new subscriptions| to be a [=/list=].
 
-   1. Let |match| be false.
+   1. Let |matched events| to be a [=/set=].
 
-   1. For each |subscription| of |session|'s [=subscriptions=]:
-
-      1. If |match| is true:
-
-         1. [=list/append=] |subscription| to |new subscriptions|.
+   1. Let |matched contexts| to be a [=/set=].
 
-         1. [=Continue=].
+   1. For each |subscription| of |session|'s [=subscriptions=]:
 
       1. If [=set/intersection=] of |subscription|'s [=subscription/event names=] and |event names| is an empty [=/set=]:
 
@@ -2072,7 +2068,7 @@ The [=remote end steps=] with |session| and |command parameters| are:
 
       1. If |top-level traversable context ids| is an empty [=/set=]:
 
-         1. If |subscription|'s [=subscription/top-level traversable ids=] [=set/size=] is not zero:
+         1. If |subscription| is not [=subscription/global=]:
 
             1. [=list/append=] |subscription| to |new subscriptions|.
 
@@ -2084,17 +2080,17 @@ The [=remote end steps=] with |session| and |command parameters| are:
 
             1. If |subscription event names| [=set/contains=] |event name|:
 
-               1. [=list/Remove=] |event name| from |event names|.
+               1. [=list/Append=] |event name| to |matched events|.
 
                1. [=list/Remove=] |event name| from |subscription event names|.
 
-         1. If |event names| [=set/size=] is zero, set |match| to true.
-
          1. If |subscription event names| is not empty:
 
-            1. Set |subscription|'s [=subscription/event names=] to |subscription event names|.
+            1. Let |cloned subscription| be a [=subscription=] with
+               [=subscription/subscription id=] set to |subscription|'s [=subscription/subscription id=],
+               [=subscription/event names=] set to a new [=/set=] containing |subscription event names|.
 
-            1. [=list/append=] |subscription| to |new subscriptions|.
+            1. [=list/append=] |cloned subscription| to |new subscriptions|.
 
       1. Otherwise:
 
@@ -2106,21 +2102,12 @@ The [=remote end steps=] with |session| and |command parameters| are:
 
           Note: unsubscribe by contexts is deprecated and will be removed in the future versions.
 
-          1. If [=set/intersection=] of |event names| and |subscription|'s [=subscription/event names=]|'s [=set/size=]
-             does not equal |event names|'s [=set/size=]:
-
-             1. [=list/append=] |subscription| to |new subscriptions|.
-
-             1. [=Continue=].
-
           1. Let |event map| be an empty [=/map=].
 
           1. For each |event name| in |subscription|'s [=subscription/event names=]:
 
               1. Set |event map|[|event name|] to [=set/clone=] of |subscription|'s [=subscription/top-level traversable ids=].
 
-          1. Let |context ids to remove| be an empty [=/set=].
-
           1. For each |event name| in |event names|:
 
               1. If |event map|[|event name|] does not exist,
@@ -2130,18 +2117,16 @@ The [=remote end steps=] with |session| and |command parameters| are:
 
                  1. If |event map|[|event name|] [=set/contains=] |top-level traversable id|:
 
-                    1. [=list/Append=] |top-level traversable id| to |context ids to remove|.
+                    1. [=list/Append=] |top-level traversable id| to |matched contexts|.
+
+                    1. [=list/Append=] |event name| to |matched events|.
 
                     1. [=list/Remove=] |top-level traversable id| from |event map|[|event name|].
 
               1. If |event map|[|event name|] is an empty [=/set=],
 
                 1. [=map/Remove=] |event map|[|event name|].
 
-          1. For each |top-level traversable id| of |context ids to remove|:
-
-             1. [=list/Remove=] |top-level traversable id| from |top-level traversable context ids|.
-
           1. For each |event name| → |remaining top-level traversable ids| in |event map|:
 
             1. Let |partial subscription| be a [=subscription=] with
@@ -2151,9 +2136,10 @@ The [=remote end steps=] with |session| and |command parameters| are:
 
             1. [=list/append=] |partial subscription| to |new subscriptions|.
 
-          1. If |top-level traversable context ids| is empty, set |match| to true.
+   1. If |matched events| does not equal |event names|, return [=error=] with [=error code=] [=invalid argument=].
 
-   1. If |match| is false, return [=error=] with [=error code=] [=invalid argument=].
+   1. If |top-level traversable context ids| is not empty and |matched contexts| does not equal
+      |top-level traversable context ids|, return [=error=] with [=error code=] [=invalid argument=].
 
    1. Set |session|'s [=subscriptions=] to |new subscriptions|.