feat(fmt): add single_line_imports option to keep single imports on one line

crates/config/src/fmt.rs

@@ -42,6 +42,8 @@ pub struct FormatterConfig {
     /// Style that determines if a broken list, should keep its elements together on their own
     /// line, before breaking individually.
     pub prefer_compact: PreferCompact,
+    /// Keep single imports on a single line even if they exceed line length.
+    pub single_line_imports: bool,
 }
 
 /// Style of integer types.
@@ -251,6 +253,7 @@ impl Default for FormatterConfig {
             pow_no_space: false,
             prefer_compact: PreferCompact::default(),
             docs_style: DocCommentStyle::default(),
+            single_line_imports: false,
         }
     }
 }

crates/fmt/README.md

@@ -128,6 +128,7 @@ The formatter supports multiple configuration options defined in `foundry.toml`.
 | `contract_new_lines` | `false` | Add a new line at the start and end of contract declarations. |
 | `sort_imports` | `false` | Sort import statements alphabetically in groups. A group is a set of imports separated by a newline. |
 | `pow_no_space` | `false` | Suppress spaces around the power operator (`**`). |
+| `single_line_imports` | `false` | Keep single imports on a single line, even if they exceed the line length limit. |
 
 > Check [`FormatterConfig`](../config/src/fmt.rs) for a more detailed explanation.
 

crates/fmt/src/state/sol.rs

@@ -215,24 +215,51 @@ impl<'ast> State<'_, 'ast> {
             }
 
             ast::ImportItems::Aliases(aliases) => {
-                self.s.cbox(self.ind);
-                self.word("{");
-                self.braces_break();
-
-                if self.config.sort_imports {
-                    let mut sorted: Vec<_> = aliases.iter().collect();
-                    sorted.sort_by_key(|(ident, _alias)| ident.name.as_str());
-                    self.print_commasep_aliases(sorted.into_iter());
+                // Check if we should keep single imports on one line
+                let use_single_line = self.config.single_line_imports && aliases.len() == 1;
+
+                if use_single_line {
+                    // Single import on one line - no box at all to avoid line wrapping
+                    self.word("{");
+                    if self.config.bracket_spacing {
+                        self.word(" ");
+                    }
+
+                    // Print single alias directly without commasep to avoid spaces
+                    if let Some((ident, alias)) = aliases.first() {
+                        self.print_ident(ident);
+                        if let Some(alias) = alias {
+                            self.word(" as ");
+                            self.print_ident(alias);
+                        }
+                    }
+
+                    if self.config.bracket_spacing {
+                        self.word(" ");
+                    }
+                    self.word("} from ");
+                    self.print_ast_str_lit(path);
                 } else {
-                    self.print_commasep_aliases(aliases.iter());
-                };
+                    // Multi-line format for multiple imports or when single_line_imports is false
+                    self.s.cbox(self.ind);
+                    self.word("{");
+                    self.braces_break();
+
+                    if self.config.sort_imports {
+                        let mut sorted: Vec<_> = aliases.iter().collect();
+                        sorted.sort_by_key(|(ident, _alias)| ident.name.as_str());
+                        self.print_commasep_aliases(sorted.into_iter());
+                    } else {
+                        self.print_commasep_aliases(aliases.iter());
+                    };
 
-                self.braces_break();
-                self.s.offset(-self.ind);
-                self.word("}");
-                self.end();
-                self.word(" from ");
-                self.print_ast_str_lit(path);
+                    self.braces_break();
+                    self.s.offset(-self.ind);
+                    self.word("}");
+                    self.end();
+                    self.word(" from ");
+                    self.print_ast_str_lit(path);
+                }
             }
         }
         self.word(";");