Replace span_to_snippet calls with snippet_opt from clippy_utils

Author: LeSeulArtichaut

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();
 

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);
                                     }
                                 },

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| {

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,