Fix issue rust-lang#4746 - formatting of import long lines

src/imports.rs

@@ -23,7 +23,7 @@ use crate::rewrite::{Rewrite, RewriteContext};
 use crate::shape::Shape;
 use crate::source_map::SpanUtils;
 use crate::spanned::Spanned;
-use crate::utils::{is_same_visibility, mk_sp, rewrite_ident};
+use crate::utils::{first_line_width, is_same_visibility, mk_sp, rewrite_ident};
 use crate::visitor::FmtVisitor;
 
 /// Returns a name imported by a `use` declaration.
@@ -1077,15 +1077,27 @@ impl Rewrite for UseTree {
     fn rewrite(&self, context: &RewriteContext<'_>, mut shape: Shape) -> Option<String> {
         let mut result = String::with_capacity(256);
         let mut iter = self.path.iter().peekable();
+        let start_shape = shape;
+
         while let Some(segment) = iter.next() {
             let segment_str = segment.rewrite(context, shape)?;
+            let mut added_len = first_line_width(&segment_str);
+            if iter.peek().is_some() {
+                added_len += 2; // 3 == "::"
+            }
+            if added_len > shape.width {
+                result.push_str(&start_shape.to_string_with_newline(context.config));
+                shape = start_shape;
+            }
+
             result.push_str(&segment_str);
             if iter.peek().is_some() {
                 result.push_str("::");
                 // 2 = "::"
                 shape = shape.offset_left(2 + segment_str.len())?;
             }
         }
+
         Some(result)
     }
 }

tests/source/issue-4746/crate.rs

@@ -0,0 +1,70 @@
+// rustfmt-imports_granularity: Crate
+
+// Long imports with reordering - from original issue
+use foo::bar;
+use foo::{foo, baz};
+use abaadfsasdfdsfdfas::aasdffjsioejr::abc::sdsdf::sdfsdfsdf::sdfsdfdsf::{
+    asdfasdefasdasdfsdfdfasdf::asdfasdasedfafasdfasdf,
+};
+
+use foo::bar;
+use foo::{foo, baz};
+use abaadfsasdfdsfdfas::aasdffjsioejr::abc::sdsdf::sdfsdfsdf::sdfsdfds::{
+    asdfasdefasdasdfsdfdfasdf::asdfasdasedfafasdfasdf,
+};
+
+// Long imports with different sizes - based on original issue
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::asdf;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::a;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z12345678::z1234567;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567890123456::z1234567;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z12345678901234567::z1234567;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::asdf;
+use a;
+
+// Very long (two lines) imports
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::{foo, baz};
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::foo;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::baz;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::{
+foo::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567,
+baz::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567};
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::{
+foo::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567,
+baz::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567};
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::{
+z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::foo,
+z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::baz};
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::foo::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::baz::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::foo;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::baz;
+use a;

tests/source/issue-4746/preserve.rs

@@ -0,0 +1,70 @@
+// rustfmt-imports_granularity: Preserve
+
+// Long imports with reordering - from original issue
+use foo::bar;
+use foo::{foo, baz};
+use abaadfsasdfdsfdfas::aasdffjsioejr::abc::sdsdf::sdfsdfsdf::sdfsdfdsf::{
+    asdfasdefasdasdfsdfdfasdf::asdfasdasedfafasdfasdf,
+};
+
+use foo::bar;
+use foo::{foo, baz};
+use abaadfsasdfdsfdfas::aasdffjsioejr::abc::sdsdf::sdfsdfsdf::sdfsdfds::{
+    asdfasdefasdasdfsdfdfasdf::asdfasdasedfafasdfasdf,
+};
+
+// Long imports with different sizes - based on original issue
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::asdf;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::a;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z12345678::z1234567;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567890123456::z1234567;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z12345678901234567::z1234567;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::asdf;
+use a;
+
+// Very long (two lines) imports
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::{foo, baz};
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::foo;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::baz;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::{
+foo::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567,
+baz::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567};
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::{
+foo::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567,
+baz::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567};
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::{
+z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::foo,
+z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::baz};
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::foo::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::baz::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567;
+use a;
+
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::foo;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::baz;
+use a;

tests/source/issue_3033.rs

@@ -0,0 +1,2 @@
+use dom::bindings::codegen::Bindings::BluetoothRemoteGATTServerBinding::BluetoothRemoteGATTServerBinding::
+    BluetoothRemoteGATTServerMethods;

tests/target/issue-4746/crate.rs

@@ -0,0 +1,101 @@
+// rustfmt-imports_granularity: Crate
+
+// Long imports with reordering - from original issue
+use abaadfsasdfdsfdfas::aasdffjsioejr::abc::sdsdf::sdfsdfsdf::sdfsdfdsf::
+    asdfasdefasdasdfsdfdfasdf::asdfasdasedfafasdfasdf;
+use foo::{bar, baz, foo};
+
+use abaadfsasdfdsfdfas::aasdffjsioejr::abc::sdsdf::sdfsdfsdf::sdfsdfds::asdfasdefasdasdfsdfdfasdf::
+    asdfasdasedfafasdfasdf;
+use foo::{bar, baz, foo};
+
+// Long imports with different sizes - based on original issue
+use a;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::asdf;
+
+use a;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::a;
+
+use a;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567;
+
+use a;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z12345678::z1234567;
+
+use a;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567890123456::
+    z1234567;
+
+use a;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z12345678901234567::z1234567;
+
+use a;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::asdf;
+
+// Very long (two lines) imports
+use a;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567;
+
+use a;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::{baz, foo};
+
+use a;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::{baz, foo};
+
+use a;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::{
+    baz::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567,
+    foo::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567,
+};
+
+use a;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::{
+    baz::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567,
+    foo::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567,
+};
+
+use a;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::z1234567::{baz, foo};
+
+use a;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::{
+    baz::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567,
+    foo::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567,
+};
+
+use a;
+use z123::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::z1234567::
+    z1234567::z1234567::{baz, foo};