Auto merge of #3674 - sinkuu:fmt_rustup, r=oli-obk

Catch up with `format_args` change

Catches up with a change in rust-lang/rust#57537. (Since the optimization is optional, this clippy PR can be merged before the rustc PR.)

Happened to fix a bug in `expect_fun_call`, that is the lint ignores more than
one arguments to `format`.

```
warning: use of `expect` followed by a function call
 --> src/main.rs:2:17
  |
2 |     Some("foo").expect(format!("{} {}", 1, 2).as_ref());
  |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `unwrap_or_else(|| panic!("{} {}", 1))`
  |
```

clippy_lints/src/format.rs

@@ -53,12 +53,17 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
                 ExprKind::Call(ref fun, ref args) => {
                     if_chain! {
                         if let ExprKind::Path(ref qpath) = fun.node;
-                        if args.len() == 3;
                         if let Some(fun_def_id) = opt_def_id(resolve_node(cx, qpath, fun.hir_id));
-                        if match_def_path(cx.tcx, fun_def_id, &paths::FMT_ARGUMENTS_NEWV1FORMATTED);
+                        let new_v1 = match_def_path(cx.tcx, fun_def_id, &paths::FMT_ARGUMENTS_NEWV1);
+                        let new_v1_fmt = match_def_path(
+                            cx.tcx,
+                            fun_def_id,
+                            &paths::FMT_ARGUMENTS_NEWV1FORMATTED
+                        );
+                        if new_v1 || new_v1_fmt;
                         if check_single_piece(&args[0]);
                         if let Some(format_arg) = get_single_string_arg(cx, &args[1]);
-                        if check_unformatted(&args[2]);
+                        if new_v1 || check_unformatted(&args[2]);
                         if let ExprKind::AddrOf(_, ref format_arg) = format_arg.node;
                         then {
                             let (message, sugg) = if_chain! {

clippy_lints/src/methods/mod.rs

@@ -1148,7 +1148,7 @@ fn lint_or_fun_call(cx: &LateContext<'_, '_>, expr: &hir::Expr, method_span: Spa
 
 /// Checks for the `EXPECT_FUN_CALL` lint.
 fn lint_expect_fun_call(cx: &LateContext<'_, '_>, expr: &hir::Expr, method_span: Span, name: &str, args: &[hir::Expr]) {
-    fn extract_format_args(arg: &hir::Expr) -> Option<&hir::HirVec<hir::Expr>> {
+    fn extract_format_args(arg: &hir::Expr) -> Option<(&hir::Expr, &hir::Expr)> {
         let arg = match &arg.node {
             hir::ExprKind::AddrOf(_, expr) => expr,
             hir::ExprKind::MethodCall(method_name, _, args)
@@ -1161,8 +1161,8 @@ fn lint_expect_fun_call(cx: &LateContext<'_, '_>, expr: &hir::Expr, method_span:
 
         if let hir::ExprKind::Call(ref inner_fun, ref inner_args) = arg.node {
             if is_expn_of(inner_fun.span, "format").is_some() && inner_args.len() == 1 {
-                if let hir::ExprKind::Call(_, ref format_args) = inner_args[0].node {
-                    return Some(format_args);
+                if let hir::ExprKind::Call(_, format_args) = &inner_args[0].node {
+                    return Some((&format_args[0], &format_args[1]));
                 }
             }
         }
@@ -1174,17 +1174,19 @@ fn lint_expect_fun_call(cx: &LateContext<'_, '_>, expr: &hir::Expr, method_span:
         cx: &LateContext<'_, '_>,
         a: &hir::Expr,
         applicability: &mut Applicability,
-    ) -> String {
+    ) -> Vec<String> {
         if let hir::ExprKind::AddrOf(_, ref format_arg) = a.node {
             if let hir::ExprKind::Match(ref format_arg_expr, _, _) = format_arg.node {
                 if let hir::ExprKind::Tup(ref format_arg_expr_tup) = format_arg_expr.node {
-                    return snippet_with_applicability(cx, format_arg_expr_tup[0].span, "..", applicability)
-                        .into_owned();
+                    return format_arg_expr_tup
+                        .iter()
+                        .map(|a| snippet_with_applicability(cx, a.span, "..", applicability).into_owned())
+                        .collect();
                 }
             }
         };
 
-        snippet(cx, a.span, "..").into_owned()
+        unreachable!()
     }
 
     fn check_general_case(
@@ -1233,14 +1235,11 @@ fn lint_expect_fun_call(cx: &LateContext<'_, '_>, expr: &hir::Expr, method_span:
         };
         let span_replace_word = method_span.with_hi(span.hi());
 
-        if let Some(format_args) = extract_format_args(arg) {
+        if let Some((fmt_spec, fmt_args)) = extract_format_args(arg) {
             let mut applicability = Applicability::MachineApplicable;
-            let args_len = format_args.len();
-            let args: Vec<String> = format_args
-                .into_iter()
-                .take(args_len - 1)
-                .map(|a| generate_format_arg_snippet(cx, a, &mut applicability))
-                .collect();
+            let mut args = vec![snippet(cx, fmt_spec.span, "..").into_owned()];
+
+            args.extend(generate_format_arg_snippet(cx, fmt_args, &mut applicability));
 
             let sugg = args.join(", ");
 

clippy_lints/src/utils/paths.rs

@@ -26,6 +26,7 @@ pub const DOUBLE_ENDED_ITERATOR: [&str; 4] = ["core", "iter", "traits", "DoubleE
 pub const DROP: [&str; 3] = ["core", "mem", "drop"];
 pub const DURATION: [&str; 3] = ["core", "time", "Duration"];
 pub const EARLY_CONTEXT: [&str; 4] = ["rustc", "lint", "context", "EarlyContext"];
+pub const FMT_ARGUMENTS_NEWV1: [&str; 4] = ["core", "fmt", "Arguments", "new_v1"];
 pub const FMT_ARGUMENTS_NEWV1FORMATTED: [&str; 4] = ["core", "fmt", "Arguments", "new_v1_formatted"];
 pub const FROM_FROM: [&str; 4] = ["core", "convert", "From", "from"];
 pub const FROM_TRAIT: [&str; 3] = ["core", "convert", "From"];

tests/ui/expect_fun_call.rs

@@ -57,6 +57,8 @@ fn expect_fun_call() {
 
     Some("foo").expect({ &format!("error") });
     Some("foo").expect(format!("error").as_ref());
+
+    Some("foo").expect(format!("{} {}", 1, 2).as_ref());
 }
 
 fn main() {}

tests/ui/expect_fun_call.stderr

@@ -36,5 +36,11 @@ error: use of `expect` followed by a function call
 LL |     Some("foo").expect(format!("error").as_ref());
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `unwrap_or_else(|| panic!("error"))`
 
-error: aborting due to 6 previous errors
+error: use of `expect` followed by a function call
+  --> $DIR/expect_fun_call.rs:61:17
+   |
+LL |     Some("foo").expect(format!("{} {}", 1, 2).as_ref());
+   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `unwrap_or_else(|| panic!("{} {}", 1, 2))`
+
+error: aborting due to 7 previous errors