Auto merge of #5760 - phansch:deprecate-regex-macro, r=Manishearth

Deprecate regex_macro lint

Closes #2586

changelog: Deprecate regex_macro lint

4 files changed, 17 insertions, 60 deletions

diff --git a/clippy_lints/src/deprecated_lints.rs b/clippy_lints/src/deprecated_lints.rs
index 6e8ca647dd7..818d8188a78 100644
--- a/clippy_lints/src/deprecated_lints.rs
+++ b/clippy_lints/src/deprecated_lints.rs
@@ -153,5 +153,13 @@ declare_deprecated_lint! {
     ///
     /// **Deprecation reason:** Associated-constants are now preferred.
     pub REPLACE_CONSTS,
-    "associated-constants `MIN`/`MAX` of integers are prefer to `{min,max}_value()` and module constants"
+    "associated-constants `MIN`/`MAX` of integers are prefered to `{min,max}_value()` and module constants"
+}
+
+declare_deprecated_lint! {
+    /// **What it does:** Nothing. This lint has been deprecated.
+    ///
+    /// **Deprecation reason:** The regex! macro does not exist anymore.
+    pub REGEX_MACRO,
+    "the regex! macro has been removed from the regex crate in 2018"
 }
diff --git a/clippy_lints/src/lib.rs b/clippy_lints/src/lib.rs
index 50116a95612..d31a597b66a 100644
--- a/clippy_lints/src/lib.rs
+++ b/clippy_lints/src/lib.rs
@@ -460,7 +460,11 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     );
     store.register_removed(
         "clippy::replace_consts",
-        "associated-constants `MIN`/`MAX` of integers are prefer to `{min,max}_value()` and module constants",
+        "associated-constants `MIN`/`MAX` of integers are prefered to `{min,max}_value()` and module constants",
+    );
+    store.register_removed(
+        "clippy::regex_macro",
+        "the regex! macro has been removed from the regex crate in 2018",
     );
     // end deprecated lints, do not remove this comment, it’s used in `update_lints`
 
@@ -755,7 +759,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
         &reference::DEREF_ADDROF,
         &reference::REF_IN_DEREF,
         &regex::INVALID_REGEX,
-        &regex::REGEX_MACRO,
         &regex::TRIVIAL_REGEX,
         &returns::NEEDLESS_RETURN,
         &returns::UNUSED_UNIT,
@@ -1380,7 +1383,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
         LintId::of(&reference::DEREF_ADDROF),
         LintId::of(&reference::REF_IN_DEREF),
         LintId::of(&regex::INVALID_REGEX),
-        LintId::of(&regex::REGEX_MACRO),
         LintId::of(&regex::TRIVIAL_REGEX),
         LintId::of(&returns::NEEDLESS_RETURN),
         LintId::of(&returns::UNUSED_UNIT),
@@ -1517,7 +1519,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
         LintId::of(&redundant_field_names::REDUNDANT_FIELD_NAMES),
         LintId::of(&redundant_pattern_matching::REDUNDANT_PATTERN_MATCHING),
         LintId::of(&redundant_static_lifetimes::REDUNDANT_STATIC_LIFETIMES),
-        LintId::of(&regex::REGEX_MACRO),
         LintId::of(&regex::TRIVIAL_REGEX),
         LintId::of(&returns::NEEDLESS_RETURN),
         LintId::of(&returns::UNUSED_UNIT),
diff --git a/clippy_lints/src/regex.rs b/clippy_lints/src/regex.rs
index 9c54c3cbac0..7405edbcd19 100644
--- a/clippy_lints/src/regex.rs
+++ b/clippy_lints/src/regex.rs
@@ -1,9 +1,9 @@
 use crate::consts::{constant, Constant};
-use crate::utils::{is_expn_of, match_def_path, match_type, paths, span_lint, span_lint_and_help};
+use crate::utils::{match_def_path, paths, span_lint, span_lint_and_help};
 use if_chain::if_chain;
 use rustc_ast::ast::{LitKind, StrStyle};
 use rustc_data_structures::fx::FxHashSet;
-use rustc_hir::{Block, BorrowKind, Crate, Expr, ExprKind, HirId};
+use rustc_hir::{BorrowKind, Expr, ExprKind, HirId};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::{declare_tool_lint, impl_lint_pass};
 use rustc_span::source_map::{BytePos, Span};
@@ -46,66 +46,15 @@ declare_clippy_lint! {
     "trivial regular expressions"
 }
 
-declare_clippy_lint! {
-    /// **What it does:** Checks for usage of `regex!(_)` which (as of now) is
-    /// usually slower than `Regex::new(_)` unless called in a loop (which is a bad
-    /// idea anyway).
-    ///
-    /// **Why is this bad?** Performance, at least for now. The macro version is
-    /// likely to catch up long-term, but for now the dynamic version is faster.
-    ///
-    /// **Known problems:** None.
-    ///
-    /// **Example:**
-    /// ```ignore
-    /// regex!("foo|bar")
-    /// ```
-    pub REGEX_MACRO,
-    style,
-    "use of `regex!(_)` instead of `Regex::new(_)`"
-}
-
 #[derive(Clone, Default)]
 pub struct Regex {
     spans: FxHashSet<Span>,
     last: Option<HirId>,
 }
 
-impl_lint_pass!(Regex => [INVALID_REGEX, REGEX_MACRO, TRIVIAL_REGEX]);
+impl_lint_pass!(Regex => [INVALID_REGEX, TRIVIAL_REGEX]);
 
 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Regex {
-    fn check_crate(&mut self, _: &LateContext<'a, 'tcx>, _: &'tcx Crate<'_>) {
-        self.spans.clear();
-    }
-
-    fn check_block(&mut self, cx: &LateContext<'a, 'tcx>, block: &'tcx Block<'_>) {
-        if_chain! {
-            if self.last.is_none();
-            if let Some(ref expr) = block.expr;
-            if match_type(cx, cx.tables().expr_ty(expr), &paths::REGEX);
-            if let Some(span) = is_expn_of(expr.span, "regex");
-            then {
-                if !self.spans.contains(&span) {
-                    span_lint(
-                        cx,
-                        REGEX_MACRO,
-                        span,
-                        "`regex!(_)` found. \
-                        Please use `Regex::new(_)`, which is faster for now."
-                    );
-                    self.spans.insert(span);
-                }
-                self.last = Some(block.hir_id);
-            }
-        }
-    }
-
-    fn check_block_post(&mut self, _: &LateContext<'a, 'tcx>, block: &'tcx Block<'_>) {
-        if self.last.map_or(false, |id| block.hir_id == id) {
-            self.last = None;
-        }
-    }
-
     fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr<'_>) {
         if_chain! {
             if let ExprKind::Call(ref fun, ref args) = expr.kind;
diff --git a/clippy_lints/src/utils/paths.rs b/clippy_lints/src/utils/paths.rs
index 3b7e9739211..4c3462802e9 100644
--- a/clippy_lints/src/utils/paths.rs
+++ b/clippy_lints/src/utils/paths.rs
@@ -98,7 +98,6 @@ pub const RANGE_TO_STD: [&str; 3] = ["std", "ops", "RangeTo"];
 pub const RC: [&str; 3] = ["alloc", "rc", "Rc"];
 pub const RC_PTR_EQ: [&str; 4] = ["alloc", "rc", "Rc", "ptr_eq"];
 pub const RECEIVER: [&str; 4] = ["std", "sync", "mpsc", "Receiver"];
-pub const REGEX: [&str; 3] = ["regex", "re_unicode", "Regex"];
 pub const REGEX_BUILDER_NEW: [&str; 5] = ["regex", "re_builder", "unicode", "RegexBuilder", "new"];
 pub const REGEX_BYTES_BUILDER_NEW: [&str; 5] = ["regex", "re_builder", "bytes", "RegexBuilder", "new"];
 pub const REGEX_BYTES_NEW: [&str; 4] = ["regex", "re_bytes", "Regex", "new"];