reorder clippy rules to their original order before passing them

We need to keep the order of the given clippy lint rules before passing them.
Since clap doesn't offer any useful interface for this purpose out of the box,
we have to handle it manually.

Signed-off-by: onur-ozkan <[email protected]>

Author: onur-ozkan

src/bootstrap/src/core/build_steps/check.rs

@@ -61,21 +61,44 @@ fn args(builder: &Builder<'_>) -> Vec<String> {
             }
         }
 
+        let all_args = std::env::args().collect::<Vec<_>>();
+
         args.extend(strings(&["--", "--cap-lints", "warn"]));
         args.extend(ignored_lints.iter().map(|lint| format!("-Aclippy::{}", lint)));
-        let mut clippy_lint_levels: Vec<String> = Vec::new();
-        allow.iter().for_each(|v| clippy_lint_levels.push(format!("-A{}", v)));
-        deny.iter().for_each(|v| clippy_lint_levels.push(format!("-D{}", v)));
-        warn.iter().for_each(|v| clippy_lint_levels.push(format!("-W{}", v)));
-        forbid.iter().for_each(|v| clippy_lint_levels.push(format!("-F{}", v)));
-        args.extend(clippy_lint_levels);
+        args.extend(get_clippy_rules_in_order(&all_args, allow, deny, warn, forbid));
         args.extend(builder.config.free_args.clone());
         args
     } else {
         builder.config.free_args.clone()
     }
 }
 
+/// We need to keep the order of the given clippy lint rules before passing them.
+/// Since clap doesn't offer any useful interface for this purpose out of the box,
+/// we have to handle it manually.
+pub(crate) fn get_clippy_rules_in_order(
+    all_args: &[String],
+    allow_rules: &[String],
+    deny_rules: &[String],
+    warn_rules: &[String],
+    forbid_rules: &[String],
+) -> Vec<String> {
+    let mut result = vec![];
+
+    for (prefix, item) in
+        [("-A", allow_rules), ("-D", deny_rules), ("-W", warn_rules), ("-F", forbid_rules)]
+    {
+        item.iter().for_each(|v| {
+            let rule = format!("{prefix}{v}");
+            let position = all_args.iter().position(|t| t == &rule).unwrap();
+            result.push((position, rule));
+        });
+    }
+
+    result.sort_by_key(|&(position, _)| position);
+    result.into_iter().map(|v| v.1).collect()
+}
+
 fn cargo_subcommand(kind: Kind) -> &'static str {
     match kind {
         Kind::Check => "check",