Fix suggestion to use uv help python on invalid install requests (#9820)

Closes #9819

Author: zanieb

crates/uv-cli/src/lib.rs

@@ -2306,7 +2306,7 @@ pub struct VenvArgs {
     /// During virtual environment creation, uv will not look for Python
     /// interpreters in virtual environments.
     ///
-    /// See `uv python help` for details on Python discovery and supported
+    /// See `uv help python` for details on Python discovery and supported
     /// request formats.
     #[arg(
         long,

crates/uv/src/commands/python/install.rs

@@ -48,7 +48,7 @@ impl InstallRequest {
         let download_request = PythonDownloadRequest::from_request(&request)
             .ok_or_else(|| {
                 anyhow::anyhow!(
-                    "`{}` is not a valid Python download request; see `uv python help` for supported formats and `uv python list --only-downloads` for available versions",
+                    "`{}` is not a valid Python download request; see `uv help python` for supported formats and `uv python list --only-downloads` for available versions",
                     request.to_canonical_string()
                 )
             })?

crates/uv/tests/it/python_install.rs

@@ -491,7 +491,7 @@ fn python_install_invalid_request() {
     ----- stdout -----
 
     ----- stderr -----
-    error: `foobar` is not a valid Python download request; see `uv python help` for supported formats and `uv python list --only-downloads` for available versions
+    error: `foobar` is not a valid Python download request; see `uv help python` for supported formats and `uv python list --only-downloads` for available versions
     "###);
 
     // Request a version we don't have a download for
@@ -824,7 +824,7 @@ fn python_install_unknown() {
     ----- stdout -----
 
     ----- stderr -----
-    error: `foobar` is not a valid Python download request; see `uv python help` for supported formats and `uv python list --only-downloads` for available versions
+    error: `foobar` is not a valid Python download request; see `uv help python` for supported formats and `uv python list --only-downloads` for available versions
     "###);
 
     context.temp_dir.child("foo").create_dir_all().unwrap();
@@ -836,7 +836,7 @@ fn python_install_unknown() {
     ----- stdout -----
 
     ----- stderr -----
-    error: `./foo` is not a valid Python download request; see `uv python help` for supported formats and `uv python list --only-downloads` for available versions
+    error: `./foo` is not a valid Python download request; see `uv help python` for supported formats and `uv python list --only-downloads` for available versions
     "###);
 }
 

docs/reference/cli.md

@@ -7726,7 +7726,7 @@ uv venv [OPTIONS] [PATH]
 
 <p>During virtual environment creation, uv will not look for Python interpreters in virtual environments.</p>
 
-<p>See <code>uv python help</code> for details on Python discovery and supported request formats.</p>
+<p>See <a href="#uv-python">uv python</a> for details on Python discovery and supported request formats.</p>
 
 <p>May also be set with the <code>UV_PYTHON</code> environment variable.</p>
 </dd><dt><code>--python-preference</code> <i>python-preference</i></dt><dd><p>Whether to prefer uv-managed or system Python installations.</p>