diff --git a/src/attr.rs b/src/attr.rs
index a263e253dd9..30fed287e55 100644
--- a/src/attr.rs
+++ b/src/attr.rs
@@ -99,7 +99,7 @@ fn format_derive(
                 ",",
                 |span| span.lo(),
                 |span| span.hi(),
-                |span| Some(context.snippet(*span).to_owned()),
+                |span| Ok(context.snippet(*span).to_owned()),
                 // We update derive attribute spans to start after the opening '('
                 // This helps us focus parsing to just what's inside #[derive(...)]
                 context.snippet_provider.span_after(attr.span, "("),
diff --git a/src/closures.rs b/src/closures.rs
index 6adfb20db8b..8a8f136bbcc 100644
--- a/src/closures.rs
+++ b/src/closures.rs
@@ -312,7 +312,7 @@ fn rewrite_closure_fn_decl(
         ",",
         |param| span_lo_for_param(param),
         |param| span_hi_for_param(context, param),
-        |param| param.rewrite(context, param_shape),
+        |param| param.rewrite_result(context, param_shape),
         context.snippet_provider.span_after(span, "|"),
         body.span.lo(),
         false,
diff --git a/src/expr.rs b/src/expr.rs
index 7eaaadb1850..2481323446e 100644
--- a/src/expr.rs
+++ b/src/expr.rs
@@ -1671,15 +1671,25 @@ fn rewrite_struct_lit<'a>(
         let rewrite = |item: &StructLitField<'_>| match *item {
             StructLitField::Regular(field) => {
                 // The 1 taken from the v_budget is for the comma.
-                let v_shape = v_shape.sub_width(1)?;
-                rewrite_field(context, field, v_shape, 0).ok()
+                rewrite_field(
+                    context,
+                    field,
+                    v_shape.sub_width(1).max_width_error(v_shape.width, span)?,
+                    0,
+                )
+                .unknown_error()
             }
             StructLitField::Base(expr) => {
                 // 2 = ..
-                let v_shape = v_shape.sub_width(2)?;
-                expr.rewrite(context, v_shape).map(|s| format!("..{}", s))
+                expr.rewrite_result(
+                    context,
+                    v_shape
+                        .offset_left(2)
+                        .max_width_error(v_shape.width, span)?,
+                )
+                .map(|s| format!("..{}", s))
             }
-            StructLitField::Rest(_) => Some("..".to_owned()),
+            StructLitField::Rest(_) => Ok("..".to_owned()),
         };
 
         let items = itemize_list(
@@ -1843,7 +1853,7 @@ fn rewrite_tuple_in_visual_indent_style<'a, T: 'a + IntoOverflowableItem<'a>>(
         ",",
         |item| item.span().lo(),
         |item| item.span().hi(),
-        |item| item.rewrite(context, nested_shape),
+        |item| item.rewrite_result(context, nested_shape),
         list_lo,
         span.hi() - BytePos(1),
         false,
diff --git a/src/imports.rs b/src/imports.rs
index 12c178e136f..eaa71312434 100644
--- a/src/imports.rs
+++ b/src/imports.rs
@@ -470,7 +470,7 @@ impl UseTree {
                     ",",
                     |tree| tree.span.lo(),
                     |tree| tree.span.hi(),
-                    |_| Some("".to_owned()), // We only need comments for now.
+                    |_| Ok("".to_owned()), // We only need comments for now.
                     context.snippet_provider.span_after(a.span, "{"),
                     a.span.hi(),
                     false,
diff --git a/src/items.rs b/src/items.rs
index 0848ec624ca..86eebc5ac85 100644
--- a/src/items.rs
+++ b/src/items.rs
@@ -629,7 +629,10 @@ impl<'a> FmtVisitor<'a> {
                     }
                 },
                 |f| f.span.hi(),
-                |f| self.format_variant(f, one_line_width, pad_discrim_ident_to),
+                |f| {
+                    self.format_variant(f, one_line_width, pad_discrim_ident_to)
+                        .unknown_error()
+                },
                 body_lo,
                 body_hi,
                 false,
@@ -2777,8 +2780,8 @@ fn rewrite_params(
         |param| param.ty.span.hi(),
         |param| {
             param
-                .rewrite(context, Shape::legacy(multi_line_budget, param_indent))
-                .or_else(|| Some(context.snippet(param.span()).to_owned()))
+                .rewrite_result(context, Shape::legacy(multi_line_budget, param_indent))
+                .or_else(|_| Ok(context.snippet(param.span()).to_owned()))
         },
         span.lo(),
         span.hi(),
@@ -3048,7 +3051,7 @@ fn rewrite_bounds_on_where_clause(
         ",",
         |pred| pred.span().lo(),
         |pred| pred.span().hi(),
-        |pred| pred.rewrite(context, shape),
+        |pred| pred.rewrite_result(context, shape),
         span_start,
         span_end,
         false,
@@ -3129,7 +3132,7 @@ fn rewrite_where_clause(
         ",",
         |pred| pred.span().lo(),
         |pred| pred.span().hi(),
-        |pred| pred.rewrite(context, Shape::legacy(budget, offset)),
+        |pred| pred.rewrite_result(context, Shape::legacy(budget, offset)),
         span_start,
         span_end,
         false,
diff --git a/src/lists.rs b/src/lists.rs
index 41afef279e9..884d5cde61f 100644
--- a/src/lists.rs
+++ b/src/lists.rs
@@ -8,7 +8,7 @@ use rustc_span::BytePos;
 use crate::comment::{find_comment_end, rewrite_comment, FindUncommented};
 use crate::config::lists::*;
 use crate::config::{Config, IndentStyle};
-use crate::rewrite::RewriteContext;
+use crate::rewrite::{RewriteContext, RewriteResult};
 use crate::shape::{Indent, Shape};
 use crate::utils::{
     count_newlines, first_line_width, last_line_width, mk_sp, starts_with_newline,
@@ -281,6 +281,7 @@ where
     let indent_str = &formatting.shape.indent.to_string(formatting.config);
     while let Some((i, item)) = iter.next() {
         let item = item.as_ref();
+        // TODO here Is it possible to 실제로 list item이 없으면..
         let inner_item = item.item.as_ref()?;
         let first = i == 0;
         let last = iter.peek().is_none();
@@ -741,7 +742,7 @@ where
     I: Iterator<Item = T>,
     F1: Fn(&T) -> BytePos,
     F2: Fn(&T) -> BytePos,
-    F3: Fn(&T) -> Option<String>,
+    F3: Fn(&T) -> RewriteResult,
 {
     type Item = ListItem;
 
@@ -778,7 +779,7 @@ where
                 item: if self.inner.peek().is_none() && self.leave_last {
                     None
                 } else {
-                    (self.get_item_string)(&item)
+                    (self.get_item_string)(&item).ok()
                 },
                 post_comment,
                 new_lines,
@@ -805,7 +806,7 @@ where
     I: Iterator<Item = T>,
     F1: Fn(&T) -> BytePos,
     F2: Fn(&T) -> BytePos,
-    F3: Fn(&T) -> Option<String>,
+    F3: Fn(&T) -> RewriteResult,
 {
     ListItems {
         snippet_provider,
diff --git a/src/macros.rs b/src/macros.rs
index a0582b061c0..8b28d19e5c1 100644
--- a/src/macros.rs
+++ b/src/macros.rs
@@ -31,7 +31,7 @@ use crate::lists::{itemize_list, write_list, ListFormatting};
 use crate::overflow;
 use crate::parse::macros::lazy_static::parse_lazy_static;
 use crate::parse::macros::{parse_expr, parse_macro_args, ParsedMacroArgs};
-use crate::rewrite::{Rewrite, RewriteContext};
+use crate::rewrite::{Rewrite, RewriteContext, RewriteError};
 use crate::shape::{Indent, Shape};
 use crate::source_map::SpanUtils;
 use crate::spanned::Spanned;
@@ -452,13 +452,13 @@ pub(crate) fn rewrite_macro_def(
         |branch| branch.span.lo(),
         |branch| branch.span.hi(),
         |branch| match branch.rewrite(context, arm_shape, multi_branch_style) {
-            Some(v) => Some(v),
+            Some(v) => Ok(v),
             // if the rewrite returned None because a macro could not be rewritten, then return the
             // original body
             None if context.macro_rewrite_failure.get() => {
-                Some(context.snippet(branch.body).trim().to_string())
+                Ok(context.snippet(branch.body).trim().to_string())
             }
-            None => None,
+            None => Err(RewriteError::Unknown),
         },
         context.snippet_provider.span_after(span, "{"),
         span.hi(),
diff --git a/src/matches.rs b/src/matches.rs
index 0dbbb6f1cac..2f8e2183996 100644
--- a/src/matches.rs
+++ b/src/matches.rs
@@ -225,7 +225,7 @@ fn rewrite_match_arms(
         "|",
         |arm| arm.span().lo(),
         |arm| arm.span().hi(),
-        |arm| arm.rewrite(context, arm_shape),
+        |arm| arm.rewrite_result(context, arm_shape),
         open_brace_pos,
         span.hi(),
         false,
diff --git a/src/overflow.rs b/src/overflow.rs
index 43d05e56807..b47882467d5 100644
--- a/src/overflow.rs
+++ b/src/overflow.rs
@@ -623,7 +623,7 @@ impl<'a> Context<'a> {
             ",",
             |item| item.span().lo(),
             |item| item.span().hi(),
-            |item| item.rewrite(self.context, self.nested_shape),
+            |item| item.rewrite_result(self.context, self.nested_shape),
             span.lo(),
             span.hi(),
             true,
diff --git a/src/patterns.rs b/src/patterns.rs
index da5a0c49aa2..476cf354458 100644
--- a/src/patterns.rs
+++ b/src/patterns.rs
@@ -343,7 +343,7 @@ fn rewrite_struct_pat(
             }
         },
         |f| f.span.hi(),
-        |f| f.rewrite(context, v_shape),
+        |f| f.rewrite_result(context, v_shape),
         context.snippet_provider.span_after(span, "{"),
         span.hi(),
         false,
@@ -551,7 +551,7 @@ fn count_wildcard_suffix_len(
         ",",
         |item| item.span().lo(),
         |item| item.span().hi(),
-        |item| item.rewrite(context, shape),
+        |item| item.rewrite_result(context, shape),
         context.snippet_provider.span_after(span, "("),
         span.hi() - BytePos(1),
         false,
diff --git a/src/reorder.rs b/src/reorder.rs
index fdbed939af5..9618098ffb7 100644
--- a/src/reorder.rs
+++ b/src/reorder.rs
@@ -15,7 +15,7 @@ use crate::config::{Config, GroupImportsTactic};
 use crate::imports::{normalize_use_trees_with_granularity, UseSegmentKind, UseTree};
 use crate::items::{is_mod_decl, rewrite_extern_crate, rewrite_mod};
 use crate::lists::{itemize_list, write_list, ListFormatting, ListItem};
-use crate::rewrite::RewriteContext;
+use crate::rewrite::{RewriteContext, RewriteErrorExt};
 use crate::shape::Shape;
 use crate::source_map::LineRangeUtils;
 use crate::spanned::Spanned;
@@ -99,7 +99,7 @@ fn rewrite_reorderable_or_regroupable_items(
                 ";",
                 |item| item.span().lo(),
                 |item| item.span().hi(),
-                |_item| Some("".to_owned()),
+                |_item| Ok("".to_owned()),
                 span.lo(),
                 span.hi(),
                 false,
@@ -151,7 +151,7 @@ fn rewrite_reorderable_or_regroupable_items(
                 ";",
                 |item| item.span().lo(),
                 |item| item.span().hi(),
-                |item| rewrite_reorderable_item(context, item, shape),
+                |item| rewrite_reorderable_item(context, item, shape).unknown_error(),
                 span.lo(),
                 span.hi(),
                 false,
diff --git a/src/types.rs b/src/types.rs
index c15ee2f3c5b..26c33ea4e43 100644
--- a/src/types.rs
+++ b/src/types.rs
@@ -388,7 +388,7 @@ where
             ",",
             |arg| arg.span().lo(),
             |arg| arg.span().hi(),
-            |arg| arg.rewrite(context, list_shape),
+            |arg| arg.rewrite_result(context, list_shape),
             list_lo,
             span.hi(),
             false,
diff --git a/src/vertical.rs b/src/vertical.rs
index 691759803e5..f455c2781e9 100644
--- a/src/vertical.rs
+++ b/src/vertical.rs
@@ -231,7 +231,6 @@ fn rewrite_aligned_items_inner<T: AlignedItem>(
         |field| {
             field
                 .rewrite_aligned_item(context, item_shape, field_prefix_max_width)
-                .ok()
         },
         span.lo(),
         span.hi(),