From e75d8ac59c53f3e22eee5c84f4ae3e0dd9df8a96 Mon Sep 17 00:00:00 2001
From: Samuel Cormier-Iijima <samuel@cormier-iijima.com>
Date: Wed, 22 Nov 2023 15:23:51 -0500
Subject: [PATCH] [formatter] Add "preserve" quote-style to mimic Black's
 skip-string-normalization

Fixes #7525
---
 .../src/expression/string/docstring.rs                 |  4 +++-
 .../ruff_python_formatter/src/expression/string/mod.rs | 10 ++++++----
 crates/ruff_python_formatter/src/options.rs            |  4 ++++
 ruff.schema.json                                       |  3 ++-
 4 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/crates/ruff_python_formatter/src/expression/string/docstring.rs b/crates/ruff_python_formatter/src/expression/string/docstring.rs
index 41f350bd4deb2..977e5f443b2cb 100644
--- a/crates/ruff_python_formatter/src/expression/string/docstring.rs
+++ b/crates/ruff_python_formatter/src/expression/string/docstring.rs
@@ -490,7 +490,9 @@ impl<'ast, 'buf, 'fmt, 'src> DocstringLinePrinter<'ast, 'buf, 'fmt, 'src> {
         // `docstring_code_examples.py` for when this check is relevant.
         let wrapped = match self.quote_style {
             QuoteStyle::Single => std::format!("'''{}'''", printed.as_code()),
-            QuoteStyle::Double => std::format!(r#""""{}""""#, printed.as_code()),
+            QuoteStyle::Double | QuoteStyle::Preserve => {
+                std::format!(r#""""{}""""#, printed.as_code())
+            }
         };
         let result = ruff_python_parser::parse(
             &wrapped,
diff --git a/crates/ruff_python_formatter/src/expression/string/mod.rs b/crates/ruff_python_formatter/src/expression/string/mod.rs
index c7e896daf2c90..639239792a509 100644
--- a/crates/ruff_python_formatter/src/expression/string/mod.rs
+++ b/crates/ruff_python_formatter/src/expression/string/mod.rs
@@ -385,7 +385,9 @@ impl StringPart {
         let quotes = match quoting {
             Quoting::Preserve => self.quotes,
             Quoting::CanChange => {
-                if self.prefix.is_raw_string() {
+                if preferred_style == QuoteStyle::Preserve {
+                    self.quotes
+                } else if self.prefix.is_raw_string() {
                     choose_quotes_raw(raw_content, self.quotes, preferred_style)
                 } else {
                     choose_quotes(raw_content, self.quotes, preferred_style)
@@ -664,7 +666,7 @@ fn choose_quotes(input: &str, quotes: StringQuotes, preferred_style: QuoteStyle)
                     QuoteStyle::Single
                 }
             }
-            QuoteStyle::Double => {
+            QuoteStyle::Double | QuoteStyle::Preserve => {
                 if double_quotes > single_quotes {
                     QuoteStyle::Single
                 } else {
@@ -716,8 +718,8 @@ impl Format<PyFormatContext<'_>> for StringQuotes {
         let quotes = match (self.style, self.triple) {
             (QuoteStyle::Single, false) => "'",
             (QuoteStyle::Single, true) => "'''",
-            (QuoteStyle::Double, false) => "\"",
-            (QuoteStyle::Double, true) => "\"\"\"",
+            (QuoteStyle::Double | QuoteStyle::Preserve, false) => "\"",
+            (QuoteStyle::Double | QuoteStyle::Preserve, true) => "\"\"\"",
         };
 
         token(quotes).fmt(f)
diff --git a/crates/ruff_python_formatter/src/options.rs b/crates/ruff_python_formatter/src/options.rs
index a07fabbb9a795..576c66c3aabf7 100644
--- a/crates/ruff_python_formatter/src/options.rs
+++ b/crates/ruff_python_formatter/src/options.rs
@@ -207,6 +207,7 @@ pub enum QuoteStyle {
     Single,
     #[default]
     Double,
+    Preserve,
 }
 
 impl QuoteStyle {
@@ -214,6 +215,7 @@ impl QuoteStyle {
         match self {
             QuoteStyle::Single => '\'',
             QuoteStyle::Double => '"',
+            QuoteStyle::Preserve => '"', // not used
         }
     }
 
@@ -222,6 +224,7 @@ impl QuoteStyle {
         match self {
             QuoteStyle::Single => QuoteStyle::Double,
             QuoteStyle::Double => QuoteStyle::Single,
+            QuoteStyle::Preserve => QuoteStyle::Preserve,
         }
     }
 }
@@ -245,6 +248,7 @@ impl FromStr for QuoteStyle {
         match s {
             "\"" | "double" | "Double" => Ok(Self::Double),
             "'" | "single" | "Single" => Ok(Self::Single),
+            "preserve" | "Preserve" => Ok(Self::Preserve),
             // TODO: replace this error with a diagnostic
             _ => Err("Value not supported for QuoteStyle"),
         }
diff --git a/ruff.schema.json b/ruff.schema.json
index 3bd21232a2551..92381de1a6522 100644
--- a/ruff.schema.json
+++ b/ruff.schema.json
@@ -2441,7 +2441,8 @@
       "type": "string",
       "enum": [
         "single",
-        "double"
+        "double",
+        "preserve"
       ]
     },
     "RelativeImportsOrder": {