Use `--with-requirements` in `uvx` error hint (#8112)

## Summary

Closes https://github.com/astral-sh/uv/issues/6845.

crates/uv-requirements/src/sources.rs

@@ -80,7 +80,8 @@ impl RequirementsSource {
         Self::RequirementsTxt(path)
     }
 
-    /// Parse a [`RequirementsSource`] from a user-provided string, assumed to be a package.
+    /// Parse a [`RequirementsSource`] from a user-provided string, assumed to be a positional
+    /// package (e.g., `uv pip install flask`).
     ///
     /// If the user provided a value that appears to be a `requirements.txt` file or a local
     /// directory, prompt them to correct it (if the terminal is interactive).
@@ -121,6 +122,48 @@ impl RequirementsSource {
         Self::Package(name)
     }
 
+    /// Parse a [`RequirementsSource`] from a user-provided string, assumed to be a `--with`
+    /// package (e.g., `uvx --with flask ruff`).
+    ///
+    /// If the user provided a value that appears to be a `requirements.txt` file or a local
+    /// directory, prompt them to correct it (if the terminal is interactive).
+    pub fn from_with_package(name: String) -> Self {
+        // If the user provided a `requirements.txt` file without `--with-requirements` (as in
+        // `uvx --with requirements.txt ruff`), prompt them to correct it.
+        #[allow(clippy::case_sensitive_file_extension_comparisons)]
+        if (name.ends_with(".txt") || name.ends_with(".in")) && Path::new(&name).is_file() {
+            let term = Term::stderr();
+            if term.is_term() {
+                let prompt = format!(
+                    "`{name}` looks like a local requirements file but was passed as a package name. Did you mean `--with-requirements {name}`?"
+                );
+                let confirmation = uv_console::confirm(&prompt, &term, true).unwrap();
+                if confirmation {
+                    return Self::from_requirements_file(name.into());
+                }
+            }
+        }
+
+        // Similarly, if the user provided a `pyproject.toml` file without `--with-requirements` (as in
+        // `uvx --with pyproject.toml ruff`), prompt them to correct it.
+        if (name == "pyproject.toml" || name == "setup.py" || name == "setup.cfg")
+            && Path::new(&name).is_file()
+        {
+            let term = Term::stderr();
+            if term.is_term() {
+                let prompt = format!(
+                    "`{name}` looks like a local metadata file but was passed as a package name. Did you mean `--with-requirements {name}`?"
+                );
+                let confirmation = uv_console::confirm(&prompt, &term, true).unwrap();
+                if confirmation {
+                    return Self::from_requirements_file(name.into());
+                }
+            }
+        }
+
+        Self::Package(name)
+    }
+
     /// Parse a [`RequirementsSource`] from a user-provided string, assumed to be a path to a source
     /// tree.
     pub fn from_source_tree(path: PathBuf) -> Self {

crates/uv/src/lib.rs

@@ -917,7 +917,7 @@ async fn run(mut cli: Cli) -> Result<ExitStatus> {
             let requirements = args
                 .with
                 .into_iter()
-                .map(RequirementsSource::from_package)
+                .map(RequirementsSource::from_with_package)
                 .chain(
                     args.with_editable
                         .into_iter()
@@ -966,7 +966,7 @@ async fn run(mut cli: Cli) -> Result<ExitStatus> {
             let requirements = args
                 .with
                 .into_iter()
-                .map(RequirementsSource::from_package)
+                .map(RequirementsSource::from_with_package)
                 .chain(
                     args.with_requirements
                         .into_iter()
@@ -1302,7 +1302,7 @@ async fn run_project(
             let requirements = args
                 .with
                 .into_iter()
-                .map(RequirementsSource::from_package)
+                .map(RequirementsSource::from_with_package)
                 .chain(
                     args.with_editable
                         .into_iter()