feat(stdlib): vim.json.encode(...,{escape_slash:boolean}) #30561

Problem:
vim.json.encode escapes every slash in string values (for example in
file paths), and is not optional. Use-case is for preventing HTML
injections (eg. injecting `</script>` closing tag); in the context of
Nvim this is rarely useful.

Solution:
- Add a `escape_slash` flag to `vim.json.encode`.
- Defaults to `false`. (This is a "breaking" change, but more like
  a bug fix.)

2 files changed, 7 insertions, 2 deletions

diff --git a/runtime/doc/lua.txt b/runtime/doc/lua.txt
index 48fa595a53..80808abd51 100644
--- a/runtime/doc/lua.txt
+++ b/runtime/doc/lua.txt
@@ -811,11 +811,14 @@ vim.json.decode({str}, {opts})                             *vim.json.decode()*
     Return: ~
         (`any`)
 
-vim.json.encode({obj})                                     *vim.json.encode()*
+vim.json.encode({obj}, {opts})                             *vim.json.encode()*
     Encodes (or "packs") Lua object {obj} as JSON in a Lua string.
 
     Parameters: ~
-      • {obj}  (`any`)
+      • {obj}   (`any`)
+      • {opts}  (`table<string,any>?`) Options table with keys:
+                • escape_slash: (boolean) (default false) When true, escapes
+                  `/` character in JSON strings
 
     Return: ~
         (`string`)
diff --git a/runtime/doc/news.txt b/runtime/doc/news.txt
index 8b4b396a26..3a3e1a8d64 100644
--- a/runtime/doc/news.txt
+++ b/runtime/doc/news.txt
@@ -60,6 +60,7 @@ DEFAULTS
   current buffer, respectively.
 • 'number', 'relativenumber', 'signcolumn', and 'foldcolumn' are disabled in
   |terminal| buffers. See |terminal-config| for an example of changing these defaults.
+• |vim.json.encode()| no longer escapes the forward slash symbol by default
 
 DIAGNOSTICS
 
@@ -169,6 +170,7 @@ The following new features were added.
 API
 
 • |nvim__ns_set()| can set properties for a namespace
+• |vim.json.encode()| has an option to enable forward slash escaping
 
 DEFAULTS