refactor: move into methods module

Author: FoseFx

clippy_lints/src/lib.register_all.rs

@@ -181,6 +181,7 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(methods::OPTION_FILTER_MAP),
     LintId::of(methods::OPTION_MAP_OR_NONE),
     LintId::of(methods::OR_FUN_CALL),
+    LintId::of(methods::OR_THEN_UNWRAP),
     LintId::of(methods::RESULT_MAP_OR_INTO_OPTION),
     LintId::of(methods::SEARCH_IS_SOME),
     LintId::of(methods::SHOULD_IMPLEMENT_TRAIT),
@@ -238,7 +239,6 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(only_used_in_recursion::ONLY_USED_IN_RECURSION),
     LintId::of(open_options::NONSENSICAL_OPEN_OPTIONS),
     LintId::of(option_env_unwrap::OPTION_ENV_UNWRAP),
-    LintId::of(or_then_unwrap::OR_THEN_UNWRAP),
     LintId::of(overflow_check_conditional::OVERFLOW_CHECK_CONDITIONAL),
     LintId::of(partialeq_ne_impl::PARTIALEQ_NE_IMPL),
     LintId::of(precedence::PRECEDENCE),

clippy_lints/src/lib.register_complexity.rs

@@ -47,6 +47,7 @@ store.register_group(true, "clippy::complexity", Some("clippy_complexity"), vec!
     LintId::of(methods::NEEDLESS_SPLITN),
     LintId::of(methods::OPTION_AS_REF_DEREF),
     LintId::of(methods::OPTION_FILTER_MAP),
+    LintId::of(methods::OR_THEN_UNWRAP),
     LintId::of(methods::SEARCH_IS_SOME),
     LintId::of(methods::SKIP_WHILE_NEXT),
     LintId::of(methods::UNNECESSARY_FILTER_MAP),
@@ -66,7 +67,6 @@ store.register_group(true, "clippy::complexity", Some("clippy_complexity"), vec!
     LintId::of(no_effect::NO_EFFECT),
     LintId::of(no_effect::UNNECESSARY_OPERATION),
     LintId::of(only_used_in_recursion::ONLY_USED_IN_RECURSION),
-    LintId::of(or_then_unwrap::OR_THEN_UNWRAP),
     LintId::of(overflow_check_conditional::OVERFLOW_CHECK_CONDITIONAL),
     LintId::of(partialeq_ne_impl::PARTIALEQ_NE_IMPL),
     LintId::of(precedence::PRECEDENCE),

clippy_lints/src/lib.register_lints.rs

@@ -319,6 +319,7 @@ store.register_lints(&[
     methods::OPTION_FILTER_MAP,
     methods::OPTION_MAP_OR_NONE,
     methods::OR_FUN_CALL,
+    methods::OR_THEN_UNWRAP,
     methods::RESULT_MAP_OR_INTO_OPTION,
     methods::SEARCH_IS_SOME,
     methods::SHOULD_IMPLEMENT_TRAIT,
@@ -404,7 +405,6 @@ store.register_lints(&[
     open_options::NONSENSICAL_OPEN_OPTIONS,
     option_env_unwrap::OPTION_ENV_UNWRAP,
     option_if_let_else::OPTION_IF_LET_ELSE,
-    or_then_unwrap::OR_THEN_UNWRAP,
     overflow_check_conditional::OVERFLOW_CHECK_CONDITIONAL,
     panic_in_result_fn::PANIC_IN_RESULT_FN,
     panic_unimplemented::PANIC,

clippy_lints/src/lib.rs

@@ -322,7 +322,6 @@ mod only_used_in_recursion;
 mod open_options;
 mod option_env_unwrap;
 mod option_if_let_else;
-mod or_then_unwrap;
 mod overflow_check_conditional;
 mod panic_in_result_fn;
 mod panic_unimplemented;
@@ -867,7 +866,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
             ignore_publish: cargo_ignore_publish,
         })
     });
-    store.register_late_pass(|| Box::new(or_then_unwrap::OrThenUnwrap));
     // add lints here, do not remove this comment, it's used in `new_lint`
 }
 

clippy_lints/src/methods/mod.rs

@@ -45,6 +45,7 @@ mod option_as_ref_deref;
 mod option_map_or_none;
 mod option_map_unwrap_or;
 mod or_fun_call;
+mod or_then_unwrap;
 mod search_is_some;
 mod single_char_add_str;
 mod single_char_insert_string;
@@ -778,6 +779,42 @@ declare_clippy_lint! {
     "using any `*or` method with a function call, which suggests `*or_else`"
 }
 
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for `.or(…).unwrap()` calls to Options and Results.
+    ///
+    /// ### Why is this bad?
+    /// You should use `.unwrap_or(…)` instead for clarity.
+    ///
+    /// ### Example
+    /// ```rust
+    /// # let fallback = "fallback";
+    /// // Result
+    /// # type Error = &'static str;
+    /// # let result: Result<&str, Error> = Err("error");
+    /// let value = result.or::<Error>(Ok(fallback)).unwrap();
+    ///
+    /// // Option
+    /// # let option: Option<&str> = None;
+    /// let value = option.or(Some(fallback)).unwrap();
+    /// ```
+    /// Use instead:
+    /// ```rust
+    /// # let fallback = "fallback";
+    /// // Result
+    /// # let result: Result<&str, &str> = Err("error");
+    /// let value = result.unwrap_or(fallback);
+    ///
+    /// // Option
+    /// # let option: Option<&str> = None;
+    /// let value = option.unwrap_or(fallback);
+    /// ```
+    #[clippy::version = "1.61.0"]
+    pub OR_THEN_UNWRAP,
+    complexity,
+    "checks for `.or(…).unwrap()` calls to Options and Results."
+}
+
 declare_clippy_lint! {
     /// ### What it does
     /// Checks for calls to `.expect(&format!(...))`, `.expect(foo(..))`,
@@ -2039,6 +2076,7 @@ impl_lint_pass!(Methods => [
     OPTION_MAP_OR_NONE,
     BIND_INSTEAD_OF_MAP,
     OR_FUN_CALL,
+    OR_THEN_UNWRAP,
     EXPECT_FUN_CALL,
     CHARS_NEXT_CMP,
     CHARS_LAST_CMP,
@@ -2474,6 +2512,9 @@ fn check_methods<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>, msrv: Optio
                     Some(("get_mut", [recv, get_arg], _)) => {
                         get_unwrap::check(cx, expr, recv, get_arg, true);
                     },
+                    Some(("or", [recv, or_arg], or_span)) => {
+                        or_then_unwrap::check(cx, expr, recv, or_arg, or_span);
+                    },
                     _ => {},
                 }
                 unwrap_used::check(cx, expr, recv);

clippy_lints/src/methods/or_then_unwrap.rs

@@ -0,0 +1,68 @@
+use clippy_utils::diagnostics::span_lint_and_help;
+use clippy_utils::ty::is_type_diagnostic_item;
+use if_chain::if_chain;
+use rustc_hir::{Expr, ExprKind, QPath};
+use rustc_lint::LateContext;
+use rustc_span::{sym, Span};
+
+use super::OR_THEN_UNWRAP;
+
+pub(super) fn check<'tcx>(
+    cx: &LateContext<'tcx>,
+    unwrap_expr: &Expr<'_>,
+    recv: &'tcx Expr<'tcx>,
+    or_arg: &'tcx Expr<'_>,
+    or_span: Span,
+) {
+    let ty = cx.typeck_results().expr_ty(recv); // get type of x (we later check if it's Option or Result)
+    let title;
+
+    if is_type_diagnostic_item(cx, ty, sym::Option) {
+        title = ".or(Some(…)).unwrap() found";
+        if !is(or_arg, "Some") {
+            return;
+        }
+    } else if is_type_diagnostic_item(cx, ty, sym::Result) {
+        title = ".or(Ok(…)).unwrap() found";
+        if !is(or_arg, "Ok") {
+            return;
+        }
+    } else {
+        // Someone has implemented a struct with .or(...).unwrap() chaining,
+        // but it's not an Option or a Result, so bail
+        return;
+    }
+
+    let unwrap_span = if let ExprKind::MethodCall(_, _, span) = unwrap_expr.kind {
+        span
+    } else {
+        // unreachable. but fallback to ident's span ("()" are missing)
+        unwrap_expr.span
+    };
+
+    span_lint_and_help(
+        cx,
+        OR_THEN_UNWRAP,
+        or_span.to(unwrap_span),
+        title,
+        None,
+        "use `unwrap_or()` instead",
+    );
+}
+
+/// is expr a Call to name?
+/// name might be "Some", "Ok", "Err", etc.
+fn is<'a>(expr: &Expr<'a>, name: &str) -> bool {
+    if_chain! {
+        if let ExprKind::Call(some_expr, _some_args) = expr.kind;
+        if let ExprKind::Path(QPath::Resolved(_, path)) = &some_expr.kind;
+        if let Some(path_segment) = path.segments.first();
+        if path_segment.ident.name.as_str() == name;
+        then {
+            true
+        }
+        else {
+            false
+        }
+    }
+}