From 5373ffdeb85d55b39671b31fc15a8183d86ff662 Mon Sep 17 00:00:00 2001 From: Oliver Schneider Date: Tue, 1 Mar 2016 10:34:45 +0100 Subject: [PATCH] suggest inserting underscores for simple cases --- src/non_expressive_names.rs | 30 +++++++++++++++++----- tests/compile-fail/non_expressive_names.rs | 4 +-- 2 files changed, 26 insertions(+), 8 deletions(-) diff --git a/src/non_expressive_names.rs b/src/non_expressive_names.rs index 944dcaeb006..fc8bb69c5bc 100644 --- a/src/non_expressive_names.rs +++ b/src/non_expressive_names.rs @@ -3,7 +3,7 @@ use syntax::codemap::Span; use syntax::parse::token::InternedString; use syntax::ast::*; use syntax::visit::{self, FnKind}; -use utils::{span_note_and_lint, in_macro}; +use utils::{span_lint_and_then, in_macro}; use strsim::levenshtein; /// **What it does:** This lint warns about names that are very similar and thus confusing @@ -95,17 +95,35 @@ impl<'a, 'b, 'c> SimilarNamesNameVisitor<'a, 'b, 'c> { existing_name.ends_with(&*interned_name) { continue; } + let mut split_at = None; if dist == 1 { // are we doing stuff like a_bar, b_bar, c_bar? - if interned_name.chars().next() != existing_name.chars().next() && interned_name.chars().nth(1) == Some('_') { - continue; + if interned_name.chars().next() != existing_name.chars().next() { + if interned_name.chars().nth(1) == Some('_') { + continue; + } + split_at = interned_name.chars().next().map(|c| c.len_utf8()); } // are we doing stuff like foo_x, foo_y, foo_z? - if interned_name.chars().rev().next() != existing_name.chars().rev().next() && interned_name.chars().rev().nth(1) == Some('_') { - continue; + if interned_name.chars().rev().next() != existing_name.chars().rev().next() { + if interned_name.chars().rev().nth(1) == Some('_') { + continue; + } + split_at = interned_name.char_indices().rev().next().map(|(i, _)| i); } } - span_note_and_lint(self.0.cx, SIMILAR_NAMES, span, "binding's name is too similar to existing binding", sp, "existing binding defined here"); + span_lint_and_then(self.0.cx, + SIMILAR_NAMES, + span, + "binding's name is too similar to existing binding", + |diag| { + diag.span_note(sp, "existing binding defined here"); + if let Some(split) = split_at { + diag.span_help(span, &format!("separate the discriminating character by an underscore like: `{}_{}`", + &interned_name[..split], + &interned_name[split..])); + } + }); return; } self.0.names.push((interned_name, span)); diff --git a/tests/compile-fail/non_expressive_names.rs b/tests/compile-fail/non_expressive_names.rs index a9a06f4234f..35dba1a82ca 100644 --- a/tests/compile-fail/non_expressive_names.rs +++ b/tests/compile-fail/non_expressive_names.rs @@ -29,9 +29,9 @@ fn main() { let blubx: i32; //~ NOTE: existing binding defined here let bluby: i32; //~ ERROR: name is too similar + //~| HELP: separate the discriminating character by an underscore like: `blub_y` let cake: i32; //~ NOTE: existing binding defined here - let caked: i32; //~ NOTE: existing binding defined here - let cakes: i32; //~ ERROR: name is too similar + let cakes: i32; let coke: i32; //~ ERROR: name is too similar }