Merge remote-tracking branch 'origin/beta_backport' into HEAD

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

diff --git a/clippy_lints/src/unwrap.rs b/clippy_lints/src/unwrap.rs
index 369b33363b5a8139fc0763067664526d61f9e405..9949a086f93aa1cc2a70641afbfdf86752c05cff 100644 (file)
--- a/clippy_lints/src/unwrap.rs
+++ b/clippy_lints/src/unwrap.rs
@@ -1,62 +1,62 @@
 use if_chain::if_chain;
 use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
-use rustc::{declare_tool_lint, lint_array};
+use rustc::{declare_lint_pass, declare_tool_lint};
 
-use crate::utils::{in_macro, match_type, paths, span_lint_and_then, usage::is_potentially_mutated};
+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 rustc::hir::intravisit::*;
 use rustc::hir::*;
-use syntax::ast::NodeId;
 use syntax::source_map::Span;
 
-/// **What it does:** Checks for calls of `unwrap[_err]()` that cannot fail.
-///
-/// **Why is this bad?** Using `if let` or `match` is more idiomatic.
-///
-/// **Known problems:** Limitations of the borrow checker might make unwrap() necessary sometimes?
-///
-/// **Example:**
-/// ```rust
-/// if option.is_some() {
-///     do_something_with(option.unwrap())
-/// }
-/// ```
-///
-/// Could be written:
-///
-/// ```rust
-/// if let Some(value) = option {
-///     do_something_with(value)
-/// }
-/// ```
 declare_clippy_lint! {
+    /// **What it does:** Checks for calls of `unwrap[_err]()` that cannot fail.
+    ///
+    /// **Why is this bad?** Using `if let` or `match` is more idiomatic.
+    ///
+    /// **Known problems:** Limitations of the borrow checker might make unwrap() necessary sometimes?
+    ///
+    /// **Example:**
+    /// ```rust
+    /// if option.is_some() {
+    ///     do_something_with(option.unwrap())
+    /// }
+    /// ```
+    ///
+    /// Could be written:
+    ///
+    /// ```rust
+    /// if let Some(value) = option {
+    ///     do_something_with(value)
+    /// }
+    /// ```
     pub UNNECESSARY_UNWRAP,
     nursery,
     "checks for calls of unwrap[_err]() that cannot fail"
 }
 
-/// **What it does:** Checks for calls of `unwrap[_err]()` that will always fail.
-///
-/// **Why is this bad?** If panicking is desired, an explicit `panic!()` should be used.
-///
-/// **Known problems:** This lint only checks `if` conditions not assignments.
-/// So something like `let x: Option<()> = None; x.unwrap();` will not be recognized.
-///
-/// **Example:**
-/// ```rust
-/// if option.is_none() {
-///     do_something_with(option.unwrap())
-/// }
-/// ```
-///
-/// This code will always panic. The if condition should probably be inverted.
 declare_clippy_lint! {
+    /// **What it does:** Checks for calls of `unwrap[_err]()` that will always fail.
+    ///
+    /// **Why is this bad?** If panicking is desired, an explicit `panic!()` should be used.
+    ///
+    /// **Known problems:** This lint only checks `if` conditions not assignments.
+    /// So something like `let x: Option<()> = None; x.unwrap();` will not be recognized.
+    ///
+    /// **Example:**
+    /// ```rust
+    /// if option.is_none() {
+    ///     do_something_with(option.unwrap())
+    /// }
+    /// ```
+    ///
+    /// This code will always panic. The if condition should probably be inverted.
     pub PANICKING_UNWRAP,
     nursery,
     "checks for calls of unwrap[_err]() that will always fail"
 }
 
-pub struct Pass;
-
 /// Visitor that keeps track of which variables are unwrappable.
 struct UnwrappableVariablesVisitor<'a, 'tcx: 'a> {
     unwrappables: Vec<UnwrapInfo<'tcx>>,
@@ -96,7 +96,7 @@ 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 {
@@ -133,7 +133,7 @@ fn visit_branch(&mut self, cond: &'tcx Expr, branch: &'tcx Expr, else_branch: bo
 
 impl<'a, 'tcx: 'a> Visitor<'tcx> for UnwrappableVariablesVisitor<'a, 'tcx> {
     fn visit_expr(&mut self, expr: &'tcx Expr) {
-        if let ExprKind::If(cond, then, els) = &expr.node {
+        if let Some((cond, then, els)) = if_block(&expr) {
             walk_expr(self, cond);
             self.visit_branch(cond, then, false);
             if let Some(els) = els {
@@ -144,10 +144,10 @@ 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 ["unwrap", "unwrap_err"].contains(&&*method_name.ident.as_str());
-                let call_to_unwrap = method_name.ident.name == "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.def == path.def);
+                    .find(|u| u.ident.res == path.res);
                 then {
                     if call_to_unwrap == unwrappable.safe_to_unwrap {
                         span_lint_and_then(
@@ -180,13 +180,9 @@ fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
     }
 }
 
-impl<'a> LintPass for Pass {
-    fn get_lints(&self) -> LintArray {
-        lint_array!(PANICKING_UNWRAP, UNNECESSARY_UNWRAP)
-    }
-}
+declare_lint_pass!(Unwrap => [PANICKING_UNWRAP, UNNECESSARY_UNWRAP]);
 
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
+impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Unwrap {
     fn check_fn(
         &mut self,
         cx: &LateContext<'a, 'tcx>,
@@ -194,9 +190,9 @@ fn check_fn(
         decl: &'tcx FnDecl,
         body: &'tcx Body,
         span: Span,
-        fn_id: NodeId,
+        fn_id: HirId,
     ) {
-        if in_macro(span) {
+        if in_macro_or_desugar(span) {
             return;
         }