From f52691a90a774775dc3bfeec0b1e19e02eef76dc Mon Sep 17 00:00:00 2001
From: Martin Fischer <martin@push-f.com>
Date: Mon, 2 Jan 2023 18:12:04 +0100
Subject: [PATCH] Print warning when running debug builds without --no-cache
 (#1549)

---
 src/commands.rs    | 12 ++++++------
 src/main_native.rs | 21 +++++++++++++++++++--
 2 files changed, 25 insertions(+), 8 deletions(-)

diff --git a/src/commands.rs b/src/commands.rs
index 91877c383a..545839485c 100644
--- a/src/commands.rs
+++ b/src/commands.rs
@@ -46,8 +46,8 @@ pub fn run(
 
     if paths.is_empty() {
         one_time_warning!(
-            "{} {}",
-            "warning:".yellow().bold(),
+            "{}: {}",
+            "warning".yellow().bold(),
             "No Python files found under the given path(s)"
         );
         return Ok(Diagnostics::default());
@@ -196,8 +196,8 @@ pub fn add_noqa(
 
     if paths.is_empty() {
         one_time_warning!(
-            "{} {}",
-            "warning:".yellow().bold(),
+            "{}: {}",
+            "warning".yellow().bold(),
             "No Python files found under the given path(s)"
         );
         return Ok(0);
@@ -270,8 +270,8 @@ pub fn show_files(
 
     if paths.is_empty() {
         one_time_warning!(
-            "{} {}",
-            "warning:".yellow().bold(),
+            "{}: {}",
+            "warning".yellow().bold(),
             "No Python files found under the given path(s)"
         );
         return Ok(());
diff --git a/src/main_native.rs b/src/main_native.rs
index 76126a619e..c7826dbab7 100644
--- a/src/main_native.rs
+++ b/src/main_native.rs
@@ -29,6 +29,7 @@ use ::ruff::settings::{pyproject, Settings};
 use ::ruff::updates;
 use anyhow::Result;
 use clap::{CommandFactory, Parser};
+use colored::Colorize;
 use notify::{recommended_watcher, RecursiveMode, Watcher};
 use path_absolutize::path_dedot;
 
@@ -172,13 +173,29 @@ pub(crate) fn inner_main() -> Result<ExitCode> {
     };
     let cache = !cli.no_cache;
 
+    #[cfg(debug_assertions)]
+    if cache {
+        // `--no-cache` doesn't respect code changes, and so is often confusing during
+        // development.
+        eprintln!(
+            "{}: debug build without --no-cache.",
+            "warning".yellow().bold()
+        );
+    }
+
     let printer = Printer::new(&format, &log_level, &autofix, &violations);
     if cli.watch {
         if !matches!(autofix, fixer::Mode::None) {
-            eprintln!("Warning: --fix is not enabled in watch mode.");
+            eprintln!(
+                "{}: --fix is not enabled in watch mode.",
+                "warning".yellow().bold()
+            );
         }
         if format != SerializationFormat::Text {
-            eprintln!("Warning: --format 'text' is used in watch mode.");
+            eprintln!(
+                "{}: --format 'text' is used in watch mode.",
+                "warning".yellow().bold()
+            );
         }
 
         // Perform an initial run instantly.