Merge #28432 nvim_win_xx_ns are EXPERIMENTAL

3 files changed, 97 insertions, 41 deletions

diff --git a/runtime/doc/api.txt b/runtime/doc/api.txt
index 86f4c3875c..13884e865d 100644
--- a/runtime/doc/api.txt
+++ b/runtime/doc/api.txt
@@ -2776,8 +2776,8 @@ nvim_buf_set_extmark({buffer}, {ns_id}, {line}, {col}, {opts})
                   • url: A URL to associate with this extmark. In the TUI, the
                     OSC 8 control sequence is used to generate a clickable
                     hyperlink to this URL.
-                  • scoped: boolean that indicates that the extmark should
-                    only be displayed in the namespace scope. (experimental)
+                  • scoped: boolean (EXPERIMENTAL) enables "scoping" for the
+                    extmark. See |nvim__win_add_ns()|
 
     Return: ~
         Id of the created/updated extmark
@@ -2859,34 +2859,41 @@ nvim_set_decoration_provider({ns_id}, {opts})
                     ["end", tick]
 <
 
-nvim_win_add_ns({window}, {ns_id})                         *nvim_win_add_ns()*
-    Adds the namespace scope to the window.
+nvim__win_add_ns({window}, {ns_id})                       *nvim__win_add_ns()*
+    EXPERIMENTAL: this API will change in the future.
+
+    Scopes a namespace to the a window, so extmarks in the namespace will be
+    active only in the given window.
 
     Parameters: ~
       • {window}  Window handle, or 0 for current window
-      • {ns_id}   the namespace to add
+      • {ns_id}   Namespace
 
     Return: ~
         true if the namespace was added, else false
 
-nvim_win_get_ns({window})                                  *nvim_win_get_ns()*
-    Gets all the namespaces scopes associated with a window.
+nvim__win_del_ns({window}, {ns_id})                       *nvim__win_del_ns()*
+    EXPERIMENTAL: this API will change in the future.
+
+    Unscopes a namespace (un-binds it from the given scope).
 
     Parameters: ~
       • {window}  Window handle, or 0 for current window
+      • {ns_id}   the namespace to remove
 
     Return: ~
-        a list of namespaces ids
+        true if the namespace was removed, else false
 
-nvim_win_remove_ns({window}, {ns_id})                   *nvim_win_remove_ns()*
-    Removes the namespace scope from the window.
+nvim__win_get_ns({window})                                *nvim__win_get_ns()*
+    EXPERIMENTAL: this API will change in the future.
+
+    Gets the namespace scopes for a given window.
 
     Parameters: ~
       • {window}  Window handle, or 0 for current window
-      • {ns_id}   the namespace to remove
 
     Return: ~
-        true if the namespace was removed, else false
+        a list of namespaces ids
 
 
 ==============================================================================
diff --git a/runtime/doc/develop.txt b/runtime/doc/develop.txt
index 7fc154441f..11c25362b6 100644
--- a/runtime/doc/develop.txt
+++ b/runtime/doc/develop.txt
@@ -383,7 +383,7 @@ Use existing common {verb} names (actions) if possible:
     - enable:       Enables/disables functionality. Signature should be
                     `enable(enable?:boolean, filter?:table)`.
     - eval:         Evaluates an expression
-    - exec:         Executes code
+    - exec:         Executes code, may return a result
     - fmt:          Formats
     - get:          Gets things (often by a query)
     - inspect:      Presents a high-level, often interactive, view
@@ -405,8 +405,8 @@ Do NOT use these deprecated verbs:
     - show:         Redundant with "print", "echo"
     - toggle:       Prefer `enable(not is_enabled())`.
 
-Use consistent names for {noun} (nouns) in API functions: buffer is called
-"buf" everywhere, not "buffer" in some places and "buf" in others.
+Use consistent names for {topic} in API functions: buffer is called "buf"
+everywhere, not "buffer" in some places and "buf" in others.
     - buf:          Buffer
     - chan:         |channel|
     - cmd:          Command
@@ -419,10 +419,10 @@ Use consistent names for {noun} (nouns) in API functions: buffer is called
     - win:          Window
 
 Do NOT use these deprecated nouns:
-    - buffer
+    - buffer        Use "buf" instead
     - callback      Use on_foo instead
-    - command
-    - window
+    - command       Use "cmd" instead
+    - window        Use "win" instead
 
 							*dev-name-events*
 Use the "on_" prefix to name event-handling callbacks and also the interface for
@@ -440,12 +440,15 @@ Example: >
 <
 							*dev-name-api*
 Use this format to name new RPC |API| functions: >
-    nvim_{noun}_{verb}_{arbitrary-qualifiers}
+    nvim_{topic}_{verb}_{arbitrary-qualifiers}
 
-If the function acts on an object then {noun} is the name of that object
-(e.g. "buf" or "win"). If the function operates in a "global" context then
-{noun} is usually omitted (but consider "namespacing" your global operations
-with a {noun} that groups functions under a common concept).
+Do not add new nvim_buf/nvim_win/nvim_tabpage APIs, unless you are certain the
+concept will NEVER be applied to more than one "scope". That is, {topic}
+should be the TOPIC ("ns", "extmark", "option", …) that acts on the scope(s)
+(buf/win/tabpage/global), it should NOT be the scope. Instead the scope should
+be a parameter (typically manifest as mutually-exclusive buf/win/… flags like
+|nvim_get_option_value()|, or less commonly as a `scope: string` field like
+|nvim_get_option_info2()|).
 
 - Example: `nvim_get_keymap('v')` operates in a global context (first
   parameter is not a Buffer). The "get" verb indicates that it gets anything
@@ -455,6 +458,58 @@ with a {noun} that groups functions under a common concept).
   and uses the "del" {verb}.
 
 
+INTERFACE PATTERNS                                      *dev-patterns*
+
+Prefer adding a single `nvim_{topic}_{verb}_…` interface for a given topic.
+
+Example: >
+
+    nvim_ns_add(
+      ns_id: int,
+      filter: {
+        handle: integer (buf/win/tabpage id)
+        scope: "global" | "win" | "buf" | "tabpage"
+      }
+    ): { ok: boolean }
+
+    nvim_ns_get(
+      ns_id: int,
+      filter: {
+        handle: integer (buf/win/tabpage id)
+        scope: "global" | "win" | "buf" | "tabpage"
+      }
+    ): { ids: int[] }
+
+    nvim_ns_del(
+      ns_id: int,
+      filter: {
+        handle: integer (buf/win/tabpage id)
+        scope: "global" | "win" | "buf" | "tabpage"
+      }
+    ): { ok: boolean }
+
+
+Anti-Example:
+
+Creating separate `nvim_xx`, `nvim_buf_xx`, `nvim_win_xx`, and
+`nvim_tabpage_xx`, functions all for the same `xx` topic, requires 4x the
+amount of documentation, tests, boilerplate, and interfaces, which users must
+comprehend, maintainers must maintain, etc. Thus the following is NOT
+recommended (compare these 12(!) functions to the above 3 functions): >
+
+    nvim_add_ns(…)
+    nvim_buf_add_ns(…)
+    nvim_win_add_ns(…)
+    nvim_tabpage_add_ns(…)
+    nvim_del_ns(…)
+    nvim_buf_del_ns(…)
+    nvim_win_del_ns(…)
+    nvim_tabpage_del_ns(…)
+    nvim_get_ns(…)
+    nvim_buf_get_ns(…)
+    nvim_win_get_ns(…)
+    nvim_tabpage_get_ns(…)
+
 API-CLIENT						*dev-api-client*
 
 							*api-client*
diff --git a/runtime/doc/news.txt b/runtime/doc/news.txt
index 111e69b0fe..42b6f4b14c 100644
--- a/runtime/doc/news.txt
+++ b/runtime/doc/news.txt
@@ -206,7 +206,18 @@ The following new APIs and features were added.
 • |'smoothscroll'| option to scroll by screen line rather than by text line
   when |'wrap'| is set.
 
-• |nvim_buf_set_extmark()| supports inline virtual text.
+• API enhancements
+  • |nvim_buf_set_extmark()| supports inline virtual text.
+  • |nvim_win_text_height()| computes the number of screen lines occupied
+    by a range of text in a given window.
+  • New RPC client type `msgpack-rpc` is added for |nvim_set_client_info()| to
+    support fully MessagePack-RPC compliant clients.
+  • Floating windows can now be hidden by setting `hide` in |nvim_open_win()| or
+    |nvim_win_set_config()|.
+  • |nvim_input_mouse()| supports mouse buttons "x1" and "x2".
+  • Added |nvim_tabpage_set_win()| to set the current window of a tabpage.
+  • |nvim__win_add_ns()| can bind a |namespace| to a window-local scope(s).
+    • Extmarks opt-in to this scoping via the `scoped` flag of |nvim_buf_set_extmark()|.
 
 • 'foldtext' now supports virtual text format. |fold-foldtext|
 
@@ -218,9 +229,6 @@ The following new APIs and features were added.
 • |vim.lpeg| and |vim.re| expose the bundled Lpeg expression grammar parser
   and its regex interface.
 
-• |nvim_win_text_height()| computes the number of screen lines occupied
-  by a range of text in a given window.
-
 • Mapping APIs now support abbreviations when mode short-name has suffix "a".
 
 • Better cmdline completion for string option value. |complete-set-option|
@@ -321,15 +329,9 @@ The following new APIs and features were added.
 • Functions that take a severity as an optional parameter (e.g.
   |vim.diagnostic.get()|) now also accept a list of severities |vim.diagnostic.severity|
 
-• New RPC client type `msgpack-rpc` is added for |nvim_set_client_info()| to
-  support fully MessagePack-RPC compliant clients.
-
 • Floating windows can now show footer with new `footer` and `footer_pos`
   config fields. Uses |hl-FloatFooter| by default.
 
-• Floating windows can now be hidden by setting `hide` in |nvim_open_win()| or
-  |nvim_win_set_config()|.
-
 • |:terminal| command now accepts some |:command-modifiers| (specifically
   |:horizontal| and those that affect splitting a window).
 
@@ -360,8 +362,6 @@ The following new APIs and features were added.
 • 'completeopt' option supports "popup" flag to show extra information in a
   floating window.
 
-• |nvim_input_mouse()| supports mouse buttons "x1" and "x2".
-
 • |v_Q-default| and |v_@-default| repeat a register for each line of a linewise
   visual selection.
 
@@ -386,14 +386,8 @@ The following new APIs and features were added.
   using the OSC 8 control sequence, enabling clickable text in supporting
   terminals.
 
-• Added |nvim_tabpage_set_win()| to set the current window of a tabpage.
-
 • Clicking on a tabpage in the tabline with the middle mouse button closes it.
 
-• |namespace| can now have window scopes. |nvim_win_add_ns()|
-
-• |extmarks| option `scoped`: only show the extmarks in its namespace's scope.
-
 • Added built-in |commenting| support.
 
 • |vim.fs.root()| finds project root directories from a list of "root