feat: locally disable formatting with specific comment

Author: blindFS

README.md

@@ -10,7 +10,7 @@
 
 ## Status
 
-* Supposed to work well with all language features of nushell v0.106
+* Supposed to work well with all language features of nushell v0.107
   * Except for some known issues of `tree-sitter-nu`
 
 > [!NOTE]
@@ -124,6 +124,24 @@ cat foo.nu | topiary format --language nu
 
 </details>
 
+### Locally disable formatting for certain expression
+
+If you don't like the formatted output of certain parts of your code,
+you can choose to disable it locally with a preceding `Topiary: disable` comment:
+
+```nushell
+...
+# Topiary: disable
+let foo = [foo, bar
+  baz, ]
+...
+```
+
+This will keep the let assignment as it is while formatting the rest of the code.
+
+> [!NOTE]
+> We do recommend reporting code style issues before resorting to this workaround.
+
 ## Editor Integration
 
 <details>

languages/nu.scm

@@ -18,6 +18,9 @@
   (path)
 ] @leaf
 
+;; TODO: new feature of the next topiary release
+;; (unescaped_interpolated_content) @keep_whitespaces
+
 ;; keep empty lines
 (_) @allow_blank_line_before
 
@@ -188,16 +191,39 @@
   (#scope_id! "consecutive_scope")
 )
 
+(val_closure
+  (_) @append_begin_scope
+  .
+  (_) @prepend_end_scope @prepend_input_softline
+  (#scope_id! "consecutive_scope")
+)
+
 (block
   "{" @append_space
   "}" @prepend_space
 )
 
+;; HACK: temporarily disable formatting after special comment
+;; abuse capture `@do_nothing` for the predicate
+(nu_script
+  (comment) @do_nothing
+  .
+  (_) @leaf
+  (#match? @do_nothing "Topiary: disable")
+)
+
+(block
+  (comment) @do_nothing
+  .
+  (_) @leaf
+  (#match? @do_nothing "Topiary: disable")
+)
+
 (val_closure
-  (_) @append_begin_scope
+  (comment) @do_nothing
   .
-  (_) @prepend_end_scope @prepend_input_softline
-  (#scope_id! "consecutive_scope")
+  (_) @leaf
+  (#match? @do_nothing "Topiary: disable")
 )
 
 (val_closure

test/expected_disable.nu

@@ -0,0 +1,17 @@
+# Topiary: disable
+let    foo =   {}
+
+{||
+  # other comments
+  let foo = 1
+  # Topiary: disable
+  let bar  =  2
+}
+
+module foo {
+
+  #Topiary: disable
+  def   should_not_be_formatted []  { }
+
+  def should_be_formatted [] { }
+}

test/input_disable.nu

@@ -0,0 +1,17 @@
+# Topiary: disable
+let    foo =   {}
+
+{  ||
+# other comments
+  let foo =   1
+  # Topiary: disable
+  let bar  =  2
+}
+
+module foo {
+
+  #Topiary: disable
+  def   should_not_be_formatted []  { }
+
+  def   should_be_formatted []  { }
+}