Handle ExprKind::ConstBlock on clippy

Author: spastorino

clippy_lints/src/loops.rs

@@ -742,6 +742,7 @@ fn never_loop_expr(expr: &Expr<'_>, main_loop_id: HirId) -> NeverLoopResult {
         | ExprKind::Closure(_, _, _, _, _)
         | ExprKind::LlvmInlineAsm(_)
         | ExprKind::Path(_)
+        | ExprKind::ConstBlock(_)
         | ExprKind::Lit(_)
         | ExprKind::Err => NeverLoopResult::Otherwise,
     }

clippy_lints/src/utils/author.rs

@@ -506,6 +506,11 @@ impl<'tcx> Visitor<'tcx> for PrintVisitor {
                 println!("    if {}.len() == {};", fields_pat, fields.len());
                 println!("    // unimplemented: field checks");
             },
+            ExprKind::ConstBlock(_) => {
+                let value_pat = self.next("value");
+                println!("Const({})", value_pat);
+                self.current = value_pat;
+            },
             // FIXME: compute length (needs type info)
             ExprKind::Repeat(ref value, _) => {
                 let value_pat = self.next("value");

clippy_lints/src/utils/eager_or_lazy.rs

@@ -23,7 +23,7 @@ use rustc_middle::hir::map::Map;
 /// This function is named so to stress that it isn't exhaustive and returns FNs.
 fn identify_some_pure_patterns(expr: &Expr<'_>) -> bool {
     match expr.kind {
-        ExprKind::Lit(..) | ExprKind::Path(..) | ExprKind::Field(..) => true,
+        ExprKind::Lit(..) | ExprKind::ConstBlock(..) | ExprKind::Path(..) | ExprKind::Field(..) => true,
         ExprKind::AddrOf(_, _, addr_of_expr) => identify_some_pure_patterns(addr_of_expr),
         ExprKind::Tup(tup_exprs) => tup_exprs.iter().all(|expr| identify_some_pure_patterns(expr)),
         ExprKind::Struct(_, fields, expr) => {

clippy_lints/src/utils/hir_utils.rs

@@ -559,6 +559,9 @@ impl<'a, 'tcx> SpanlessHash<'a, 'tcx> {
                 self.hash_name(path.ident.name);
                 self.hash_exprs(args);
             },
+            ExprKind::ConstBlock(ref l_id) => {
+                self.hash_body(l_id.body);
+            },
             ExprKind::Repeat(ref e, ref l_id) => {
                 self.hash_expr(e);
                 self.hash_body(l_id.body);

clippy_lints/src/utils/inspector.rs

@@ -338,6 +338,11 @@ fn print_expr(cx: &LateContext<'_>, expr: &hir::Expr<'_>, indent: usize) {
                 print_expr(cx, base, indent + 1);
             }
         },
+        hir::ExprKind::ConstBlock(ref anon_const) => {
+            println!("{}ConstBlock", ind);
+            println!("{}anon_const:", ind);
+            print_expr(cx, &cx.tcx.hir().body(anon_const.body).value, indent + 1);
+        },
         hir::ExprKind::Repeat(ref val, ref anon_const) => {
             println!("{}Repeat", ind);
             println!("{}value:", ind);

clippy_lints/src/utils/sugg.rs

@@ -110,6 +110,7 @@ impl<'a> Sugg<'a> {
             | hir::ExprKind::Index(..)
             | hir::ExprKind::InlineAsm(..)
             | hir::ExprKind::LlvmInlineAsm(..)
+            | hir::ExprKind::ConstBlock(..)
             | hir::ExprKind::Lit(..)
             | hir::ExprKind::Loop(..)
             | hir::ExprKind::MethodCall(..)
@@ -157,6 +158,7 @@ impl<'a> Sugg<'a> {
             | ast::ExprKind::Index(..)
             | ast::ExprKind::InlineAsm(..)
             | ast::ExprKind::LlvmInlineAsm(..)
+            | ast::ExprKind::ConstBlock(..)
             | ast::ExprKind::Lit(..)
             | ast::ExprKind::Loop(..)
             | ast::ExprKind::MacCall(..)