extract the formaing string and the values

Author: ABouttefeux

clippy_lints/src/bool_assert_comparison.rs

@@ -112,12 +112,12 @@ impl<'tcx> LateLintPass<'tcx> for BoolAssertComparison {
                         let arg_span = match fmt_args {
                             [] => None,
                             [a] => Some(format!(
-                                ".., {}",
+                                "{}",
                                 Sugg::hir_with_applicability(cx, a, "..", &mut applicability)
                             )),
                             _ => {
                                 let mut args = format!(
-                                    ".., {}",
+                                    "{}",
                                     Sugg::hir_with_applicability(cx, fmt_args[0], "..", &mut applicability)
                                 );
                                 for el in &fmt_args[1..] {

clippy_utils/src/higher.rs

@@ -446,13 +446,10 @@ pub fn extract_assert_macro_args<'tcx>(e: &'tcx Expr<'tcx>) -> Option<Vec<&'tcx
                     if args_assert_failed.len() >= 4;
                     if let ExprKind::Call(_, args) =  args_assert_failed[3].kind;
                     if !args.is_empty();
-                    if let ExprKind::Match(expr_match, _, _ ) = args[0].kind;
-                    if let ExprKind::Match(tup_match, _, _) = expr_match.kind;
-                    if let ExprKind::Tup(tup_args_list) = tup_match.kind;
+                    if let Some (mut format_arg_expn) = FormatArgsExpn::parse(&args[0]);
                     then {
-                        for arg in tup_args_list {
-                            vec_arg.push(arg);
-                        }
+                        vec_arg.push(format_arg_expn.format_string);
+                        vec_arg.append(&mut format_arg_expn.value_args);
                     }
                 }
                 return Some(vec_arg);
@@ -524,6 +521,8 @@ impl FormatExpn<'tcx> {
 
 /// A parsed `format_args!` expansion
 pub struct FormatArgsExpn<'tcx> {
+    /// The fist argument, the fromat string, as an expr
+    pub format_string: &'tcx Expr<'tcx>,
     /// Span of the first argument, the format string
     pub format_string_span: Span,
     /// Values passed after the format string
@@ -585,6 +584,7 @@ impl FormatArgsExpn<'tcx> {
                 .collect();
             then {
                 Some(FormatArgsExpn {
+                    format_string:strs_ref,
                     format_string_span: strs_ref.span,
                     value_args,
                     format_string_parts,