Implement equatable if let lint

[rust.git] / clippy_utils / src / higher.rs

diff --git a/clippy_utils/src/higher.rs b/clippy_utils/src/higher.rs
index 05a4a0143195080328d5d06788bb9d1bd75ffdc8..ba4d50bf74469307cbfedc51e1c979c532c74d4e 100644 (file)
--- a/clippy_utils/src/higher.rs
+++ b/clippy_utils/src/higher.rs
@@ -105,8 +105,7 @@ pub fn hir(cx: &LateContext<'_>, expr: &Expr<'hir>) -> Option<Self> {
             if_else,
         ) = expr.kind
         {
-            let hir = cx.tcx.hir();
-            let mut iter = hir.parent_iter(expr.hir_id);
+            let mut iter = cx.tcx.hir().parent_iter(expr.hir_id);
             if let Some((_, Node::Block(Block { stmts: [], .. }))) = iter.next() {
                 if let Some((
                     _,
@@ -524,28 +523,12 @@ pub fn parse(expr: &'tcx Expr<'tcx>) -> Option<Self> {
             if let ExpnKind::Macro(_, name) = expr.span.ctxt().outer_expn_data().kind;
             let name = name.as_str();
             if name.ends_with("format_args") || name.ends_with("format_args_nl");
-
-            if let ExprKind::Match(inner_match, [arm], _) = expr.kind;
-
-            // `match match`, if you will
-            if let ExprKind::Match(args, [inner_arm], _) = inner_match.kind;
-            if let ExprKind::Tup(value_args) = args.kind;
-            if let Some(value_args) = value_args
-                .iter()
-                .map(|e| match e.kind {
-                    ExprKind::AddrOf(_, _, e) => Some(e),
-                    _ => None,
-                })
-                .collect();
-            if let ExprKind::Array(args) = inner_arm.body.kind;
-
-            if let ExprKind::Block(Block { stmts: [], expr: Some(expr), .. }, _) = arm.body.kind;
-            if let ExprKind::Call(_, call_args) = expr.kind;
-            if let Some((strs_ref, fmt_expr)) = match call_args {
+            if let ExprKind::Call(_, args) = expr.kind;
+            if let Some((strs_ref, args, fmt_expr)) = match args {
                 // Arguments::new_v1
-                [strs_ref, _] => Some((strs_ref, None)),
+                [strs_ref, args] => Some((strs_ref, args, None)),
                 // Arguments::new_v1_formatted
-                [strs_ref, _, fmt_expr] => Some((strs_ref, Some(fmt_expr))),
+                [strs_ref, args, fmt_expr, _unsafe_arg] => Some((strs_ref, args, Some(fmt_expr))),
                 _ => None,
             };
             if let ExprKind::AddrOf(BorrowKind::Ref, _, strs_arr) = strs_ref.kind;
@@ -561,6 +544,17 @@ pub fn parse(expr: &'tcx Expr<'tcx>) -> Option<Self> {
                     None
                 })
                 .collect();
+            if let ExprKind::AddrOf(BorrowKind::Ref, _, args) = args.kind;
+            if let ExprKind::Match(args, [arm], _) = args.kind;
+            if let ExprKind::Tup(value_args) = args.kind;
+            if let Some(value_args) = value_args
+                .iter()
+                .map(|e| match e.kind {
+                    ExprKind::AddrOf(_, _, e) => Some(e),
+                    _ => None,
+                })
+                .collect();
+            if let ExprKind::Array(args) = arm.body.kind;
             then {
                 Some(FormatArgsExpn {
                     format_string_span: strs_ref.span,
@@ -608,3 +602,33 @@ pub fn is_from_for_desugar(local: &hir::Local<'_>) -> bool {
 
     false
 }
+
+/// A parsed `panic!` expansion
+pub struct PanicExpn<'tcx> {
+    /// Span of `panic!(..)`
+    pub call_site: Span,
+    /// Inner `format_args!` expansion
+    pub format_args: FormatArgsExpn<'tcx>,
+}
+
+impl PanicExpn<'tcx> {
+    /// Parses an expanded `panic!` invocation
+    pub fn parse(expr: &'tcx Expr<'tcx>) -> Option<Self> {
+        if_chain! {
+            if let ExprKind::Block(block, _) = expr.kind;
+            if let Some(init) = block.expr;
+            if let ExprKind::Call(_, [format_args]) = init.kind;
+            let expn_data = expr.span.ctxt().outer_expn_data();
+            if let ExprKind::AddrOf(_, _, format_args) = format_args.kind;
+            if let Some(format_args) = FormatArgsExpn::parse(format_args);
+            then {
+                Some(PanicExpn {
+                    call_site: expn_data.call_site,
+                    format_args,
+                })
+            } else {
+                None
+            }
+        }
+    }
+}