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

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

diff --git a/clippy_lints/src/ok_if_let.rs b/clippy_lints/src/ok_if_let.rs
index 65b13688ff626f5ba45fed653f004a1c772e8ebe..01d41f679dbb35db173bf37d4f306ee3812053ec 100644 (file)
--- a/clippy_lints/src/ok_if_let.rs
+++ b/clippy_lints/src/ok_if_let.rs
@@ -1,62 +1,59 @@
-use rustc::lint::*;
+use crate::utils::{match_type, method_chain_args, paths, snippet, span_help_and_lint};
+use if_chain::if_chain;
 use rustc::hir::*;
-use utils::{paths, method_chain_args, span_help_and_lint, match_type, snippet};
+use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
+use rustc::{declare_lint_pass, declare_tool_lint};
 
-/// **What it does:*** Checks for unnecessary `ok()` in if let.
-///
-/// **Why is this bad?** Calling `ok()` in if let is unnecessary, instead match on `Ok(pat)`
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-/// ```rust
-/// for result in iter {
-///     if let Some(bench) = try!(result).parse().ok() {
-///         vec.push(bench)
-///     }
-/// }
-/// ```
-/// Could be written:
-///
-/// ```rust
-/// for result in iter {
-///     if let Ok(bench) = try!(result).parse() {
-///         vec.push(bench)
-///     }
-/// }
-/// ```
-declare_lint! {
+declare_clippy_lint! {
+    /// **What it does:*** Checks for unnecessary `ok()` in if let.
+    ///
+    /// **Why is this bad?** Calling `ok()` in if let is unnecessary, instead match
+    /// on `Ok(pat)`
+    ///
+    /// **Known problems:** None.
+    ///
+    /// **Example:**
+    /// ```ignore
+    /// for result in iter {
+    ///     if let Some(bench) = try!(result).parse().ok() {
+    ///         vec.push(bench)
+    ///     }
+    /// }
+    /// ```
+    /// Could be written:
+    ///
+    /// ```ignore
+    /// for result in iter {
+    ///     if let Ok(bench) = try!(result).parse() {
+    ///         vec.push(bench)
+    ///     }
+    /// }
+    /// ```
     pub IF_LET_SOME_RESULT,
-    Warn,
+    style,
     "usage of `ok()` in `if let Some(pat)` statements is unnecessary, match on `Ok(pat)` instead"
 }
 
-#[derive(Copy, Clone)]
-pub struct Pass;
+declare_lint_pass!(OkIfLet => [IF_LET_SOME_RESULT]);
 
-impl LintPass for Pass {
-    fn get_lints(&self) -> LintArray {
-        lint_array!(IF_LET_SOME_RESULT)
-    }
-}
-
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
+impl<'a, 'tcx> LateLintPass<'a, 'tcx> for OkIfLet {
     fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
-        if_let_chain! {[ //begin checking variables
-            let ExprMatch(ref op, ref body, ref source) = expr.node, //test if expr is a match
-            let MatchSource::IfLetDesugar { .. } = *source, //test if it is an If Let
-            let ExprMethodCall(_, _, ref result_types) = op.node, //check is expr.ok() has type Result<T,E>.ok()
-            let PatKind::TupleStruct(QPath::Resolved(_, ref x), ref y, _)  = body[0].pats[0].node, //get operation
-            method_chain_args(op, &["ok"]).is_some() //test to see if using ok() methoduse std::marker::Sized;
+        if_chain! { //begin checking variables
+            if let ExprKind::Match(ref op, ref body, ref source) = expr.node; //test if expr is a match
+            if let MatchSource::IfLetDesugar { .. } = *source; //test if it is an If Let
+            if let ExprKind::MethodCall(_, _, ref result_types) = op.node; //check is expr.ok() has type Result<T,E>.ok()
+            if let PatKind::TupleStruct(QPath::Resolved(_, ref x), ref y, _)  = body[0].pats[0].node; //get operation
+            if method_chain_args(op, &["ok"]).is_some(); //test to see if using ok() methoduse std::marker::Sized;
 
-        ], {
-            let is_result_type = match_type(cx, cx.tcx.tables().expr_ty(&result_types[0]), &paths::RESULT);
-            let some_expr_string = snippet(cx, y[0].span, "");
-            if print::path_to_string(x) == "Some" && is_result_type {
-                span_help_and_lint(cx, IF_LET_SOME_RESULT, expr.span,
-                "Matching on `Some` with `ok()` is redundant",
-                &format!("Consider matching on `Ok({})` and removing the call to `ok` instead", some_expr_string));
+            then {
+                let is_result_type = match_type(cx, cx.tables.expr_ty(&result_types[0]), &paths::RESULT);
+                let some_expr_string = snippet(cx, y[0].span, "");
+                if print::to_string(print::NO_ANN, |s| s.print_path(x, false)) == "Some" && is_result_type {
+                    span_help_and_lint(cx, IF_LET_SOME_RESULT, expr.span,
+                    "Matching on `Some` with `ok()` is redundant",
+                    &format!("Consider matching on `Ok({})` and removing the call to `ok` instead", some_expr_string));
+                }
             }
-        }}
+        }
     }
 }