Introduce snippet_with_applicability and hir_with_applicability functions

[rust.git] / clippy_lints / src / utils / sugg.rs

diff --git a/clippy_lints/src/utils/sugg.rs b/clippy_lints/src/utils/sugg.rs
index f849cef093a65b27fdd5e11ee43463bd84b87b1d..5bb35474403abbcec61156781ec0087d8565a37d 100644 (file)
--- a/clippy_lints/src/utils/sugg.rs
+++ b/clippy_lints/src/utils/sugg.rs
@@ -1,3 +1,13 @@
+// Copyright 2014-2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+
 //! Contains utility functions to generate suggestions.
 #![deny(clippy::missing_docs_in_private_items)]
 
@@ -6,6 +16,7 @@
 use crate::rustc::lint::{EarlyContext, LateContext, LintContext};
 use crate::rustc_errors;
 use std::borrow::Cow;
+use std::convert::TryInto;
 use std::fmt::Display;
 use std;
 use crate::syntax::source_map::{CharPos, Span};
@@ -15,6 +26,7 @@
 use crate::syntax::ast;
 use crate::utils::{higher, snippet, snippet_opt};
 use crate::syntax_pos::{BytePos, Pos};
+use crate::rustc_errors::Applicability;
 
 /// A helper type to build suggestion correctly handling parenthesis.
 pub enum Sugg<'a> {
@@ -84,6 +96,15 @@ pub fn hir(cx: &LateContext<'_, '_>, expr: &hir::Expr, default: &'a str) -> Self
         Self::hir_opt(cx, expr).unwrap_or_else(|| Sugg::NonParen(Cow::Borrowed(default)))
     }
 
+    pub fn hir_with_applicability(cx: &LateContext<'_, '_>, expr: &hir::Expr, default: &'a str, applicability: &mut Applicability) -> Self {
+        Self::hir_opt(cx, expr).unwrap_or_else(|| {
+            if *applicability == Applicability::MachineApplicable {
+                *applicability = Applicability::HasPlaceholders;
+            }
+            Sugg::NonParen(Cow::Borrowed(default))
+        })
+    }
+
     /// Prepare a suggestion from an expression.
     pub fn ast(cx: &EarlyContext<'_>, expr: &ast::Expr, default: &'a str) -> Self {
         use crate::syntax::ast::RangeLimits;
@@ -461,7 +482,7 @@ pub trait DiagnosticBuilderExt<'a, T: LintContext<'a>> {
     /// ```rust,ignore
     /// db.suggest_item_with_attr(cx, item, "#[derive(Default)]");
     /// ```
-    fn suggest_item_with_attr<D: Display + ?Sized>(&mut self, cx: &T, item: Span, msg: &str, attr: &D);
+    fn suggest_item_with_attr<D: Display + ?Sized>(&mut self, cx: &T, item: Span, msg: &str, attr: &D, applicability: Applicability);
 
     /// Suggest to add an item before another.
     ///
@@ -475,7 +496,7 @@ pub trait DiagnosticBuilderExt<'a, T: LintContext<'a>> {
     ///     bar();
     /// }");
     /// ```
-    fn suggest_prepend_item(&mut self, cx: &T, item: Span, msg: &str, new_item: &str);
+    fn suggest_prepend_item(&mut self, cx: &T, item: Span, msg: &str, new_item: &str, applicability: Applicability);
 
     /// Suggest to completely remove an item.
     ///
@@ -488,19 +509,24 @@ pub trait DiagnosticBuilderExt<'a, T: LintContext<'a>> {
     /// ```rust,ignore
     /// db.suggest_remove_item(cx, item, "remove this")
     /// ```
-    fn suggest_remove_item(&mut self, cx: &T, item: Span, msg: &str);
+    fn suggest_remove_item(&mut self, cx: &T, item: Span, msg: &str, applicability: Applicability);
 }
 
 impl<'a, 'b, 'c, T: LintContext<'c>> DiagnosticBuilderExt<'c, T> for rustc_errors::DiagnosticBuilder<'b> {
-    fn suggest_item_with_attr<D: Display + ?Sized>(&mut self, cx: &T, item: Span, msg: &str, attr: &D) {
+    fn suggest_item_with_attr<D: Display + ?Sized>(&mut self, cx: &T, item: Span, msg: &str, attr: &D, applicability: Applicability) {
         if let Some(indent) = indentation(cx, item) {
             let span = item.with_hi(item.lo());
 
-            self.span_suggestion(span, msg, format!("{}\n{}", attr, indent));
+            self.span_suggestion_with_applicability(
+                        span,
+                        msg,
+                        format!("{}\n{}", attr, indent),
+                        applicability,
+                        );
         }
     }
 
-    fn suggest_prepend_item(&mut self, cx: &T, item: Span, msg: &str, new_item: &str) {
+    fn suggest_prepend_item(&mut self, cx: &T, item: Span, msg: &str, new_item: &str, applicability: Applicability) {
         if let Some(indent) = indentation(cx, item) {
             let span = item.with_hi(item.lo());
 
@@ -517,23 +543,33 @@ fn suggest_prepend_item(&mut self, cx: &T, item: Span, msg: &str, new_item: &str
                 })
                 .collect::<String>();
 
-            self.span_suggestion(span, msg, format!("{}\n{}", new_item, indent));
+            self.span_suggestion_with_applicability(
+                        span,
+                        msg,
+                        format!("{}\n{}", new_item, indent),
+                        applicability,
+                        );
         }
     }
 
-    fn suggest_remove_item(&mut self, cx: &T, item: Span, msg: &str) {
+    fn suggest_remove_item(&mut self, cx: &T, item: Span, msg: &str, applicability: Applicability) {
         let mut remove_span = item;
         let hi = cx.sess().source_map().next_point(remove_span).hi();
         let fmpos = cx.sess().source_map().lookup_byte_offset(hi);
 
-        if let Some(ref src) = fmpos.fm.src {
+        if let Some(ref src) = fmpos.sf.src {
             let non_whitespace_offset = src[fmpos.pos.to_usize()..].find(|c| c != ' ' && c != '\t' && c != '\n');
 
             if let Some(non_whitespace_offset) = non_whitespace_offset {
-                remove_span = remove_span.with_hi(remove_span.hi() + BytePos(non_whitespace_offset as u32))
+                remove_span = remove_span.with_hi(remove_span.hi() + BytePos(non_whitespace_offset.try_into().expect("offset too large")))
             }
         }
 
-        self.span_suggestion(remove_span, msg, String::new());
+        self.span_suggestion_with_applicability(
+            remove_span,
+            msg,
+            String::new(),
+            applicability,
+        );
     }
 }