Remove chain_split_single_child option

Author: nrc

Configurations.md

@@ -440,27 +440,6 @@ let lorem = ipsum.dolor().sit().amet().consectetur().adipiscing().elit();
 #### Lines longer than `chain_width`:
 See [`chain_indent`](#chain_indent).
 
-## `chain_split_single_child`
-
-Split a chain with a single child if its length exceeds [`chain_width`](#chain_width).
-
-- **Default value**: `false`
-- **Possible values**: `false`, `true`
-
-#### `false` (default):
-
-```rust
-let files = fs::read_dir("tests/coverage/source").expect("Couldn't read source dir");
-```
-
-#### `true`:
-
-```rust
-let files = fs::read_dir("tests/coverage/source")
-    .expect("Couldn't read source dir");
-```
-
-See also [`chain_width`](#chain_width).
 
 ## `combine_control_expr`
 

src/chains.rs

@@ -158,7 +158,7 @@ pub fn rewrite_chain(expr: &ast::Expr, context: &RewriteContext, shape: Shape) -
     } else {
         rewrites.iter().fold(0, |a, b| a + b.len()) + parent_rewrite.len()
     } + suffix_try_num;
-    let one_line_budget = if rewrites.is_empty() && !context.config.chain_split_single_child() {
+    let one_line_budget = if rewrites.is_empty() {
         shape.width
     } else {
         min(shape.width, context.config.chain_width())

src/config.rs

@@ -570,8 +570,6 @@ create_config! {
     report_fixme: ReportTactic, ReportTactic::Never, false,
         "Report all, none or unnumbered occurrences of FIXME in source file comments";
     chain_width: usize, 60, false, "Maximum length of a chain to fit on a single line";
-    chain_split_single_child: bool, false, false, "Split a chain with a single child if its length \
-                                            exceeds `chain_width`";
     imports_indent: IndentStyle, IndentStyle::Visual, false, "Indent of imports";
     imports_layout: ListTactic, ListTactic::Mixed, false, "Item layout inside a import block";
     reorder_extern_crates: bool, true, false, "Reorder extern crate statements alphabetically";