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Move lint_map_unwrap_or to its own file

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Wilco Kusee 2019-01-19 12:53:21 +01:00
parent 54ab22f6db
commit 4cf720abbe
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GPG key ID: D5B2BB5CDC3334BC
2 changed files with 51 additions and 44 deletions
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46
clippy_lints/src/methods/mod.rs
View file

@ -22,6 +22,7 @@ use syntax::ast;
use syntax::source_map::{BytePos, Span};
use syntax::symbol::LocalInternedString;
mod option_map_unwrap_or;
mod unnecessary_filter_map;
#[derive(Clone)]
@ -836,7 +837,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
["unwrap", "get_mut"] => lint_get_unwrap(cx, expr, arg_lists[1], true),
["unwrap", ..] => lint_unwrap(cx, expr, arg_lists[0]),
["expect", "ok"] => lint_ok_expect(cx, expr, arg_lists[1]),
["unwrap_or", "map"] => lint_map_unwrap_or(cx, expr, arg_lists[1], arg_lists[0]),
["unwrap_or", "map"] => option_map_unwrap_or::lint(cx, expr, arg_lists[1], arg_lists[0]),
["unwrap_or_else", "map"] => lint_map_unwrap_or_else(cx, expr, arg_lists[1], arg_lists[0]),
["map_or", ..] => lint_map_or_none(cx, expr, arg_lists[0]),
["next", "filter"] => lint_filter_next(cx, expr, arg_lists[1]),
@ -1769,49 +1770,6 @@ fn lint_ok_expect(cx: &LateContext<'_, '_>, expr: &hir::Expr, ok_args: &[hir::Ex
}
}
/// lint use of `map().unwrap_or()` for `Option`s
fn lint_map_unwrap_or(cx: &LateContext<'_, '_>, expr: &hir::Expr, map_args: &[hir::Expr], unwrap_args: &[hir::Expr]) {
// lint if the caller of `map()` is an `Option`
let unwrap_ty = cx.tables.expr_ty(&unwrap_args[1]);
if match_type(cx, cx.tables.expr_ty(&map_args[0]), &paths::OPTION) && is_copy(cx, unwrap_ty) {
// get snippets for args to map() and unwrap_or()
let map_snippet = snippet(cx, map_args[1].span, "..");
let unwrap_snippet = snippet(cx, unwrap_args[1].span, "..");
// lint message
// comparing the snippet from source to raw text ("None") below is safe
// because we already have checked the type.
let arg = if unwrap_snippet == "None" { "None" } else { "a" };
let suggest = if unwrap_snippet == "None" {
"and_then(f)"
} else {
"map_or(a, f)"
};
let msg = &format!(
"called `map(f).unwrap_or({})` on an Option value. \
This can be done more directly by calling `{}` instead",
arg, suggest
);
// lint, with note if neither arg is > 1 line and both map() and
// unwrap_or() have the same span
let multiline = map_snippet.lines().count() > 1 || unwrap_snippet.lines().count() > 1;
let same_span = map_args[1].span.ctxt() == unwrap_args[1].span.ctxt();
if same_span && !multiline {
let suggest = if unwrap_snippet == "None" {
format!("and_then({})", map_snippet)
} else {
format!("map_or({}, {})", unwrap_snippet, map_snippet)
};
let note = format!(
"replace `map({}).unwrap_or({})` with `{}`",
map_snippet, unwrap_snippet, suggest
);
span_note_and_lint(cx, OPTION_MAP_UNWRAP_OR, expr.span, msg, expr.span, &note);
} else if same_span && multiline {
span_lint(cx, OPTION_MAP_UNWRAP_OR, expr.span, msg);
};
}
}
/// lint use of `map().flatten()` for `Iterators`
fn lint_map_flatten<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, expr: &'tcx hir::Expr, map_args: &'tcx [hir::Expr]) {
// lint if caller of `.map().flatten()` is an Iterator

49
clippy_lints/src/methods/option_map_unwrap_or.rs Normal file
View file

@ -0,0 +1,49 @@
use crate::utils::paths;
use crate::utils::{is_copy, match_type, snippet, span_lint, span_note_and_lint};
use rustc::hir;
use rustc::lint::LateContext;
use super::OPTION_MAP_UNWRAP_OR;
/// lint use of `map().unwrap_or()` for `Option`s
pub(super) fn lint(cx: &LateContext<'_, '_>, expr: &hir::Expr, map_args: &[hir::Expr], unwrap_args: &[hir::Expr]) {
// lint if the caller of `map()` is an `Option`
let unwrap_ty = cx.tables.expr_ty(&unwrap_args[1]);
if match_type(cx, cx.tables.expr_ty(&map_args[0]), &paths::OPTION) && is_copy(cx, unwrap_ty) {
// get snippets for args to map() and unwrap_or()
let map_snippet = snippet(cx, map_args[1].span, "..");
let unwrap_snippet = snippet(cx, unwrap_args[1].span, "..");
// lint message
// comparing the snippet from source to raw text ("None") below is safe
// because we already have checked the type.
let arg = if unwrap_snippet == "None" { "None" } else { "a" };
let suggest = if unwrap_snippet == "None" {
"and_then(f)"
} else {
"map_or(a, f)"
};
let msg = &format!(
"called `map(f).unwrap_or({})` on an Option value. \
This can be done more directly by calling `{}` instead",
arg, suggest
);
// lint, with note if neither arg is > 1 line and both map() and
// unwrap_or() have the same span
let multiline = map_snippet.lines().count() > 1 || unwrap_snippet.lines().count() > 1;
let same_span = map_args[1].span.ctxt() == unwrap_args[1].span.ctxt();
if same_span && !multiline {
let suggest = if unwrap_snippet == "None" {
format!("and_then({})", map_snippet)
} else {
format!("map_or({}, {})", unwrap_snippet, map_snippet)
};
let note = format!(
"replace `map({}).unwrap_or({})` with `{}`",
map_snippet, unwrap_snippet, suggest
);
span_note_and_lint(cx, OPTION_MAP_UNWRAP_OR, expr.span, msg, expr.span, &note);
} else if same_span && multiline {
span_lint(cx, OPTION_MAP_UNWRAP_OR, expr.span, msg);
};
}
}