Auto merge of #7542 - LeSeulArtichaut:cleanups, r=flip1995

Cleanup usage of `span_to_snippet` and `LintContext::sess`

- avoid using `SourceMap::span_to_snippet` directly and use `clippy_utils::source::snippet_opt` instead
- don't use `LintContext::sess()` on `EarlyContext`s which have a `sess` field directly available, saving the import of `LintContext`

changelog: none

11 files changed, 36 insertions, 34 deletions

diff --git a/clippy_lints/src/as_conversions.rs b/clippy_lints/src/as_conversions.rs
index 7c39a3e2ce3..0be460d67a7 100644
--- a/clippy_lints/src/as_conversions.rs
+++ b/clippy_lints/src/as_conversions.rs
@@ -1,6 +1,6 @@
 use clippy_utils::diagnostics::span_lint_and_help;
 use rustc_ast::ast::{Expr, ExprKind};
-use rustc_lint::{EarlyContext, EarlyLintPass, LintContext};
+use rustc_lint::{EarlyContext, EarlyLintPass};
 use rustc_middle::lint::in_external_macro;
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 
@@ -47,7 +47,7 @@ declare_lint_pass!(AsConversions => [AS_CONVERSIONS]);
 
 impl EarlyLintPass for AsConversions {
     fn check_expr(&mut self, cx: &EarlyContext<'_>, expr: &Expr) {
-        if in_external_macro(cx.sess(), expr.span) {
+        if in_external_macro(cx.sess, expr.span) {
             return;
         }
 
diff --git a/clippy_lints/src/else_if_without_else.rs b/clippy_lints/src/else_if_without_else.rs
index 0541ac5eccc..b64246515f3 100644
--- a/clippy_lints/src/else_if_without_else.rs
+++ b/clippy_lints/src/else_if_without_else.rs
@@ -2,7 +2,7 @@
 
 use clippy_utils::diagnostics::span_lint_and_help;
 use rustc_ast::ast::{Expr, ExprKind};
-use rustc_lint::{EarlyContext, EarlyLintPass, LintContext};
+use rustc_lint::{EarlyContext, EarlyLintPass};
 use rustc_middle::lint::in_external_macro;
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 
@@ -49,7 +49,7 @@ declare_lint_pass!(ElseIfWithoutElse => [ELSE_IF_WITHOUT_ELSE]);
 
 impl EarlyLintPass for ElseIfWithoutElse {
     fn check_expr(&mut self, cx: &EarlyContext<'_>, mut item: &Expr) {
-        if in_external_macro(cx.sess(), item.span) {
+        if in_external_macro(cx.sess, item.span) {
             return;
         }
 
diff --git a/clippy_lints/src/if_not_else.rs b/clippy_lints/src/if_not_else.rs
index 28db7233d70..3ce91d421ba 100644
--- a/clippy_lints/src/if_not_else.rs
+++ b/clippy_lints/src/if_not_else.rs
@@ -3,7 +3,7 @@
 
 use clippy_utils::diagnostics::span_lint_and_help;
 use rustc_ast::ast::{BinOpKind, Expr, ExprKind, UnOp};
-use rustc_lint::{EarlyContext, EarlyLintPass, LintContext};
+use rustc_lint::{EarlyContext, EarlyLintPass};
 use rustc_middle::lint::in_external_macro;
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 
@@ -48,7 +48,7 @@ declare_lint_pass!(IfNotElse => [IF_NOT_ELSE]);
 
 impl EarlyLintPass for IfNotElse {
     fn check_expr(&mut self, cx: &EarlyContext<'_>, item: &Expr) {
-        if in_external_macro(cx.sess(), item.span) {
+        if in_external_macro(cx.sess, item.span) {
             return;
         }
         if let ExprKind::If(ref cond, _, Some(ref els)) = item.kind {
diff --git a/clippy_lints/src/items_after_statements.rs b/clippy_lints/src/items_after_statements.rs
index 429c6ed7d2d..3736d237642 100644
--- a/clippy_lints/src/items_after_statements.rs
+++ b/clippy_lints/src/items_after_statements.rs
@@ -2,7 +2,7 @@
 
 use clippy_utils::diagnostics::span_lint;
 use rustc_ast::ast::{Block, ItemKind, StmtKind};
-use rustc_lint::{EarlyContext, EarlyLintPass, LintContext};
+use rustc_lint::{EarlyContext, EarlyLintPass};
 use rustc_middle::lint::in_external_macro;
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 
@@ -54,7 +54,7 @@ declare_lint_pass!(ItemsAfterStatements => [ITEMS_AFTER_STATEMENTS]);
 
 impl EarlyLintPass for ItemsAfterStatements {
     fn check_block(&mut self, cx: &EarlyContext<'_>, item: &Block) {
-        if in_external_macro(cx.sess(), item.span) {
+        if in_external_macro(cx.sess, item.span) {
             return;
         }
 
@@ -68,7 +68,7 @@ impl EarlyLintPass for ItemsAfterStatements {
         // lint on all further items
         for stmt in stmts {
             if let StmtKind::Item(ref it) = *stmt {
-                if in_external_macro(cx.sess(), it.span) {
+                if in_external_macro(cx.sess, it.span) {
                     return;
                 }
                 if let ItemKind::MacroDef(..) = it.kind {
diff --git a/clippy_lints/src/literal_representation.rs b/clippy_lints/src/literal_representation.rs
index 699ddce0cff..0e5121ca3d7 100644
--- a/clippy_lints/src/literal_representation.rs
+++ b/clippy_lints/src/literal_representation.rs
@@ -10,7 +10,7 @@ use clippy_utils::{
 use if_chain::if_chain;
 use rustc_ast::ast::{Expr, ExprKind, Lit, LitKind};
 use rustc_errors::Applicability;
-use rustc_lint::{EarlyContext, EarlyLintPass, LintContext};
+use rustc_lint::{EarlyContext, EarlyLintPass};
 use rustc_middle::lint::in_external_macro;
 use rustc_session::{declare_tool_lint, impl_lint_pass};
 use std::iter;
@@ -222,7 +222,7 @@ impl_lint_pass!(LiteralDigitGrouping => [
 
 impl EarlyLintPass for LiteralDigitGrouping {
     fn check_expr(&mut self, cx: &EarlyContext<'_>, expr: &Expr) {
-        if in_external_macro(cx.sess(), expr.span) {
+        if in_external_macro(cx.sess, expr.span) {
             return;
         }
 
@@ -415,7 +415,7 @@ impl_lint_pass!(DecimalLiteralRepresentation => [DECIMAL_LITERAL_REPRESENTATION]
 
 impl EarlyLintPass for DecimalLiteralRepresentation {
     fn check_expr(&mut self, cx: &EarlyContext<'_>, expr: &Expr) {
-        if in_external_macro(cx.sess(), expr.span) {
+        if in_external_macro(cx.sess, expr.span) {
             return;
         }
 
diff --git a/clippy_lints/src/methods/from_iter_instead_of_collect.rs b/clippy_lints/src/methods/from_iter_instead_of_collect.rs
index b4188d9ed30..99c03844f49 100644
--- a/clippy_lints/src/methods/from_iter_instead_of_collect.rs
+++ b/clippy_lints/src/methods/from_iter_instead_of_collect.rs
@@ -1,10 +1,11 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet_opt;
 use clippy_utils::ty::implements_trait;
 use clippy_utils::{is_expr_path_def_path, paths, sugg};
 use if_chain::if_chain;
 use rustc_errors::Applicability;
 use rustc_hir as hir;
-use rustc_lint::{LateContext, LintContext};
+use rustc_lint::LateContext;
 use rustc_middle::ty::Ty;
 use rustc_span::sym;
 
@@ -43,7 +44,7 @@ fn extract_turbofish(cx: &LateContext<'_>, expr: &hir::Expr<'_>, ty: Ty<'tcx>) -
 
     let call_site = expr.span.source_callsite();
     if_chain! {
-        if let Ok(snippet) = cx.sess().source_map().span_to_snippet(call_site);
+        if let Some(snippet) = snippet_opt(cx, call_site);
         let snippet_split = snippet.split("::").collect::<Vec<_>>();
         if let Some((_, elements)) = snippet_split.split_last();
 
diff --git a/clippy_lints/src/misc_early/mod.rs b/clippy_lints/src/misc_early/mod.rs
index 06fe967dafc..b32feab4ee3 100644
--- a/clippy_lints/src/misc_early/mod.rs
+++ b/clippy_lints/src/misc_early/mod.rs
@@ -12,7 +12,7 @@ use clippy_utils::source::snippet_opt;
 use rustc_ast::ast::{Expr, Generics, Lit, LitFloatType, LitIntType, LitKind, NodeId, Pat, PatKind};
 use rustc_ast::visit::FnKind;
 use rustc_data_structures::fx::FxHashMap;
-use rustc_lint::{EarlyContext, EarlyLintPass, LintContext};
+use rustc_lint::{EarlyContext, EarlyLintPass};
 use rustc_middle::lint::in_external_macro;
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 use rustc_span::source_map::Span;
@@ -307,7 +307,7 @@ impl EarlyLintPass for MiscEarlyLints {
     }
 
     fn check_expr(&mut self, cx: &EarlyContext<'_>, expr: &Expr) {
-        if in_external_macro(cx.sess(), expr.span) {
+        if in_external_macro(cx.sess, expr.span) {
             return;
         }
         double_neg::check(cx, expr);
diff --git a/clippy_lints/src/misc_early/unneeded_field_pattern.rs b/clippy_lints/src/misc_early/unneeded_field_pattern.rs
index 2201cf56d52..fff533167ed 100644
--- a/clippy_lints/src/misc_early/unneeded_field_pattern.rs
+++ b/clippy_lints/src/misc_early/unneeded_field_pattern.rs
@@ -1,6 +1,7 @@
 use clippy_utils::diagnostics::{span_lint, span_lint_and_help};
+use clippy_utils::source::snippet_opt;
 use rustc_ast::ast::{Pat, PatKind};
-use rustc_lint::{EarlyContext, LintContext};
+use rustc_lint::EarlyContext;
 
 use super::UNNEEDED_FIELD_PATTERN;
 
@@ -48,7 +49,7 @@ pub(super) fn check(cx: &EarlyContext<'_>, pat: &Pat) {
                             match field.pat.kind {
                                 PatKind::Wild => {},
                                 _ => {
-                                    if let Ok(n) = cx.sess().source_map().span_to_snippet(field.span) {
+                                    if let Some(n) = snippet_opt(cx, field.span) {
                                         normal.push(n);
                                     }
                                 },
diff --git a/clippy_lints/src/redundant_closure_call.rs b/clippy_lints/src/redundant_closure_call.rs
index a79b2fe76e2..7314bce83e0 100644
--- a/clippy_lints/src/redundant_closure_call.rs
+++ b/clippy_lints/src/redundant_closure_call.rs
@@ -8,7 +8,7 @@ use rustc_errors::Applicability;
 use rustc_hir as hir;
 use rustc_hir::intravisit as hir_visit;
 use rustc_hir::intravisit::Visitor as HirVisitor;
-use rustc_lint::{EarlyContext, EarlyLintPass, LateContext, LateLintPass, LintContext};
+use rustc_lint::{EarlyContext, EarlyLintPass, LateContext, LateLintPass};
 use rustc_middle::hir::map::Map;
 use rustc_middle::lint::in_external_macro;
 use rustc_session::{declare_lint_pass, declare_tool_lint};
@@ -63,7 +63,7 @@ impl<'ast> ast_visit::Visitor<'ast> for ReturnVisitor {
 
 impl EarlyLintPass for RedundantClosureCall {
     fn check_expr(&mut self, cx: &EarlyContext<'_>, expr: &ast::Expr) {
-        if in_external_macro(cx.sess(), expr.span) {
+        if in_external_macro(cx.sess, expr.span) {
             return;
         }
         if_chain! {
diff --git a/clippy_lints/src/reference.rs b/clippy_lints/src/reference.rs
index e0930d69ab9..77b6e60d893 100644
--- a/clippy_lints/src/reference.rs
+++ b/clippy_lints/src/reference.rs
@@ -54,7 +54,8 @@ impl EarlyLintPass for DerefAddrOf {
             then {
                 let mut applicability = Applicability::MachineApplicable;
                 let sugg = if e.span.from_expansion() {
-                    if let Ok(macro_source) = cx.sess.source_map().span_to_snippet(e.span) {
+                    #[allow(clippy::option_if_let_else)]
+                    if let Some(macro_source) = snippet_opt(cx, e.span) {
                         // Remove leading whitespace from the given span
                         // e.g: ` $visitor` turns into `$visitor`
                         let trim_leading_whitespaces = |span| {
diff --git a/clippy_lints/src/unused_unit.rs b/clippy_lints/src/unused_unit.rs
index 9ed5e585f84..1164ac4938f 100644
--- a/clippy_lints/src/unused_unit.rs
+++ b/clippy_lints/src/unused_unit.rs
@@ -1,10 +1,10 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::source::position_before_rarrow;
+use clippy_utils::source::{position_before_rarrow, snippet_opt};
 use if_chain::if_chain;
 use rustc_ast::ast;
 use rustc_ast::visit::FnKind;
 use rustc_errors::Applicability;
-use rustc_lint::{EarlyContext, EarlyLintPass, LintContext};
+use rustc_lint::{EarlyContext, EarlyLintPass};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 use rustc_span::source_map::Span;
 use rustc_span::BytePos;
@@ -125,17 +125,16 @@ fn is_unit_expr(expr: &ast::Expr) -> bool {
 }
 
 fn lint_unneeded_unit_return(cx: &EarlyContext<'_>, ty: &ast::Ty, span: Span) {
-    let (ret_span, appl) = if let Ok(fn_source) = cx.sess().source_map().span_to_snippet(span.with_hi(ty.span.hi())) {
-        position_before_rarrow(&fn_source).map_or((ty.span, Applicability::MaybeIncorrect), |rpos| {
-            (
-                #[allow(clippy::cast_possible_truncation)]
-                ty.span.with_lo(BytePos(span.lo().0 + rpos as u32)),
-                Applicability::MachineApplicable,
-            )
-        })
-    } else {
-        (ty.span, Applicability::MaybeIncorrect)
-    };
+    let (ret_span, appl) =
+        snippet_opt(cx, span.with_hi(ty.span.hi())).map_or((ty.span, Applicability::MaybeIncorrect), |fn_source| {
+            position_before_rarrow(&fn_source).map_or((ty.span, Applicability::MaybeIncorrect), |rpos| {
+                (
+                    #[allow(clippy::cast_possible_truncation)]
+                    ty.span.with_lo(BytePos(span.lo().0 + rpos as u32)),
+                    Applicability::MachineApplicable,
+                )
+            })
+        });
     span_lint_and_sugg(
         cx,
         UNUSED_UNIT,