Optional source map generation (#6894)

crates/ruff_formatter/src/printer/mod.rs

@@ -396,6 +396,10 @@ impl<'a> Printer<'a> {
     }
 
     fn push_marker(&mut self) {
+        if self.options.source_map_generation.is_disabled() {
+            return;
+        }
+
         let marker = SourceMarker {
             source: self.state.source_position,
             dest: self.state.buffer.text_len(),

crates/ruff_formatter/src/printer/printer_options/mod.rs

@@ -14,39 +14,10 @@ pub struct PrinterOptions {
 
     /// Whether the printer should use tabs or spaces to indent code and if spaces, by how many.
     pub indent_style: IndentStyle,
-}
 
-#[derive(Debug, Copy, Clone, Eq, PartialEq)]
-pub struct PrintWidth(u32);
-
-impl PrintWidth {
-    pub fn new(width: u32) -> Self {
-        Self(width)
-    }
-}
-
-impl Default for PrintWidth {
-    fn default() -> Self {
-        LineWidth::default().into()
-    }
-}
-
-impl From<LineWidth> for PrintWidth {
-    fn from(width: LineWidth) -> Self {
-        Self(u32::from(u16::from(width)))
-    }
-}
-
-impl From<PrintWidth> for usize {
-    fn from(width: PrintWidth) -> Self {
-        width.0 as usize
-    }
-}
-
-impl From<PrintWidth> for u32 {
-    fn from(width: PrintWidth) -> Self {
-        width.0
-    }
+    /// Whether the printer should build a source map that allows mapping positions in the source document
+    /// to positions in the formatted document.
+    pub source_map_generation: SourceMapGeneration,
 }
 
 impl<'a, O> From<&'a O> for PrinterOptions
@@ -94,6 +65,64 @@ impl PrinterOptions {
     }
 }
 
+#[derive(Debug, Copy, Clone, Eq, PartialEq)]
+pub struct PrintWidth(u32);
+
+impl PrintWidth {
+    pub fn new(width: u32) -> Self {
+        Self(width)
+    }
+}
+
+impl Default for PrintWidth {
+    fn default() -> Self {
+        LineWidth::default().into()
+    }
+}
+
+impl From<LineWidth> for PrintWidth {
+    fn from(width: LineWidth) -> Self {
+        Self(u32::from(u16::from(width)))
+    }
+}
+
+impl From<PrintWidth> for usize {
+    fn from(width: PrintWidth) -> Self {
+        width.0 as usize
+    }
+}
+
+impl From<PrintWidth> for u32 {
+    fn from(width: PrintWidth) -> Self {
+        width.0
+    }
+}
+
+/// Configures whether the formatter and printer generate a source map that allows mapping
+/// positions in the source document to positions in the formatted code.
+#[derive(Copy, Clone, Debug, Eq, PartialEq, Default)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+pub enum SourceMapGeneration {
+    /// The formatter generates no source map.
+    #[default]
+    Disabled,
+
+    /// The formatter generates a source map that allows mapping positions in the source document
+    /// to positions in the formatted document. The ability to map positions is useful for range formatting
+    /// or when trying to identify where to move the cursor so that it matches its position in the source document.
+    Enabled,
+}
+
+impl SourceMapGeneration {
+    pub const fn is_enabled(self) -> bool {
+        matches!(self, SourceMapGeneration::Enabled)
+    }
+
+    pub const fn is_disabled(self) -> bool {
+        matches!(self, SourceMapGeneration::Disabled)
+    }
+}
+
 #[allow(dead_code)]
 #[derive(Clone, Debug, Eq, PartialEq, Default)]
 pub enum LineEnding {