Auto merge of #4551 - mikerite:fix-ice-reporting, r=llogiq

[rust.git] / clippy_lints / src / unwrap.rs

diff --git a/clippy_lints/src/unwrap.rs b/clippy_lints/src/unwrap.rs
index 9949a086f93aa1cc2a70641afbfdf86752c05cff..061d4aa7460c457f97edea353d314a7d6e26a4fc 100644 (file)
--- a/clippy_lints/src/unwrap.rs
+++ b/clippy_lints/src/unwrap.rs
@@ -2,10 +2,7 @@
 use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
 use rustc::{declare_lint_pass, declare_tool_lint};
 
-use crate::utils::sym;
-use crate::utils::{
-    higher::if_block, in_macro_or_desugar, match_type, paths, span_lint_and_then, usage::is_potentially_mutated,
-};
+use crate::utils::{higher::if_block, match_type, paths, span_lint_and_then, usage::is_potentially_mutated};
 use rustc::hir::intravisit::*;
 use rustc::hir::*;
 use syntax::source_map::Span;
@@ -15,10 +12,12 @@
     ///
     /// **Why is this bad?** Using `if let` or `match` is more idiomatic.
     ///
-    /// **Known problems:** Limitations of the borrow checker might make unwrap() necessary sometimes?
+    /// **Known problems:** None
     ///
     /// **Example:**
     /// ```rust
+    /// # let option = Some(0);
+    /// # fn do_something_with(_x: usize) {}
     /// if option.is_some() {
     ///     do_something_with(option.unwrap())
     /// }
@@ -27,12 +26,14 @@
     /// Could be written:
     ///
     /// ```rust
+    /// # let option = Some(0);
+    /// # fn do_something_with(_x: usize) {}
     /// if let Some(value) = option {
     ///     do_something_with(value)
     /// }
     /// ```
     pub UNNECESSARY_UNWRAP,
-    nursery,
+    complexity,
     "checks for calls of unwrap[_err]() that cannot fail"
 }
 
@@ -46,6 +47,8 @@
     ///
     /// **Example:**
     /// ```rust
+    /// # let option = Some(0);
+    /// # fn do_something_with(_x: usize) {}
     /// if option.is_none() {
     ///     do_something_with(option.unwrap())
     /// }
@@ -53,12 +56,12 @@
     ///
     /// This code will always panic. The if condition should probably be inverted.
     pub PANICKING_UNWRAP,
-    nursery,
+    correctness,
     "checks for calls of unwrap[_err]() that will always fail"
 }
 
 /// Visitor that keeps track of which variables are unwrappable.
-struct UnwrappableVariablesVisitor<'a, 'tcx: 'a> {
+struct UnwrappableVariablesVisitor<'a, 'tcx> {
     unwrappables: Vec<UnwrapInfo<'tcx>>,
     cx: &'a LateContext<'a, 'tcx>,
 }
@@ -75,7 +78,7 @@ struct UnwrapInfo<'tcx> {
 
 /// Collects the information about unwrappable variables from an if condition
 /// The `invert` argument tells us whether the condition is negated.
-fn collect_unwrap_info<'a, 'tcx: 'a>(
+fn collect_unwrap_info<'a, 'tcx>(
     cx: &'a LateContext<'a, 'tcx>,
     expr: &'tcx Expr,
     invert: bool,
@@ -96,7 +99,7 @@ fn collect_unwrap_info<'a, 'tcx: 'a>(
             if let ExprKind::MethodCall(method_name, _, args) = &expr.node;
             if let ExprKind::Path(QPath::Resolved(None, path)) = &args[0].node;
             let ty = cx.tables.expr_ty(&args[0]);
-            if match_type(cx, ty, &*paths::OPTION) || match_type(cx, ty, &*paths::RESULT);
+            if match_type(cx, ty, &paths::OPTION) || match_type(cx, ty, &paths::RESULT);
             let name = method_name.ident.as_str();
             if ["is_some", "is_none", "is_ok", "is_err"].contains(&&*name);
             then {
@@ -114,7 +117,7 @@ fn collect_unwrap_info<'a, 'tcx: 'a>(
     Vec::new()
 }
 
-impl<'a, 'tcx: 'a> UnwrappableVariablesVisitor<'a, 'tcx> {
+impl<'a, 'tcx> UnwrappableVariablesVisitor<'a, 'tcx> {
     fn visit_branch(&mut self, cond: &'tcx Expr, branch: &'tcx Expr, else_branch: bool) {
         let prev_len = self.unwrappables.len();
         for unwrap_info in collect_unwrap_info(self.cx, cond, else_branch) {
@@ -131,7 +134,7 @@ fn visit_branch(&mut self, cond: &'tcx Expr, branch: &'tcx Expr, else_branch: bo
     }
 }
 
-impl<'a, 'tcx: 'a> Visitor<'tcx> for UnwrappableVariablesVisitor<'a, 'tcx> {
+impl<'a, 'tcx> Visitor<'tcx> for UnwrappableVariablesVisitor<'a, 'tcx> {
     fn visit_expr(&mut self, expr: &'tcx Expr) {
         if let Some((cond, then, els)) = if_block(&expr) {
             walk_expr(self, cond);
@@ -144,8 +147,8 @@ fn visit_expr(&mut self, expr: &'tcx Expr) {
             if_chain! {
                 if let ExprKind::MethodCall(ref method_name, _, ref args) = expr.node;
                 if let ExprKind::Path(QPath::Resolved(None, ref path)) = args[0].node;
-                if [*sym::unwrap, *sym::unwrap_err].contains(&method_name.ident.name);
-                let call_to_unwrap = method_name.ident.name == *sym::unwrap;
+                if [sym!(unwrap), sym!(unwrap_err)].contains(&method_name.ident.name);
+                let call_to_unwrap = method_name.ident.name == sym!(unwrap);
                 if let Some(unwrappable) = self.unwrappables.iter()
                     .find(|u| u.ident.res == path.res);
                 then {
@@ -192,7 +195,7 @@ fn check_fn(
         span: Span,
         fn_id: HirId,
     ) {
-        if in_macro_or_desugar(span) {
+        if span.from_expansion() {
             return;
         }