Merge pull request rust-lang#2165 from topecongiro/issue-2164

Handle large types on struct fields

src/expr.rs

@@ -2596,7 +2596,7 @@ pub fn rewrite_assign_rhs<S: Into<String>, R: Rewrite>(
     Some(lhs + &rhs)
 }
 
-fn choose_rhs<R: Rewrite>(
+pub fn choose_rhs<R: Rewrite>(
     context: &RewriteContext,
     expr: &R,
     shape: Shape,

src/items.rs

@@ -23,7 +23,7 @@ use codemap::{LineRangeUtils, SpanUtils};
 use comment::{combine_strs_with_missing_comments, contains_comment, recover_comment_removed,
               recover_missing_comment_in_span, rewrite_missing_comment, FindUncommented};
 use config::{BraceStyle, Config, Density, IndentStyle, ReturnIndent};
-use expr::{format_expr, is_empty_block, is_simple_block_stmt, rewrite_assign_rhs,
+use expr::{choose_rhs, format_expr, is_empty_block, is_simple_block_stmt, rewrite_assign_rhs,
            rewrite_call_inner, ExprType};
 use lists::{definitive_tactic, itemize_list, write_list, DefinitiveListTactic, ListFormatting,
             ListItem, ListTactic, Separator, SeparatorPlace, SeparatorTactic};
@@ -1200,7 +1200,7 @@ pub fn format_struct_struct(
     let items_str = rewrite_with_alignment(
         fields,
         context,
-        Shape::indented(offset, context.config),
+        Shape::indented(offset, context.config).sub_width(1)?,
         mk_sp(body_lo, span.hi()),
         one_line_budget,
     )?;
@@ -1480,34 +1480,23 @@ pub fn rewrite_struct_field(
         spacing.push(' ');
     }
     let ty_shape = shape.offset_left(overhead + spacing.len())?;
-    if let Some(ref ty) = field.ty.rewrite(context, ty_shape) {
+    let mut orig_ty = field.ty.rewrite(context, ty_shape);
+    if let Some(ref ty) = orig_ty {
         if !ty.contains('\n') {
             return Some(attr_prefix + &spacing + ty);
         }
     }
 
-    // We must use multiline.
-    let new_shape = shape.with_max_width(context.config);
-    let ty_rewritten = field.ty.rewrite(context, new_shape)?;
-
+    // We must use multiline. We are going to put attributes and a field on different lines.
+    // 1 = " "
+    let rhs_shape = shape.offset_left(last_line_width(&prefix) + 1)?;
+    orig_ty = field.ty.rewrite(context, rhs_shape);
     let field_str = if prefix.is_empty() {
-        ty_rewritten
-    } else if prefix.len() + first_line_width(&ty_rewritten) + 1 <= shape.width {
-        prefix + " " + &ty_rewritten
+        orig_ty?
     } else {
-        let type_offset = shape.indent.block_indent(context.config);
-        let nested_shape = Shape::indented(type_offset, context.config);
-        let nested_ty = field.ty.rewrite(context, nested_shape)?;
-        prefix + "\n" + &type_offset.to_string(context.config) + &nested_ty
+        prefix + &choose_rhs(context, &*field.ty, rhs_shape, orig_ty)?
     };
-    combine_strs_with_missing_comments(
-        context,
-        &attrs_str,
-        &field_str,
-        missing_span,
-        shape,
-        attrs_extendable,
-    )
+    combine_strs_with_missing_comments(context, &attrs_str, &field_str, missing_span, shape, false)
 }
 
 pub struct StaticParts<'a> {

src/types.rs

@@ -25,7 +25,8 @@ use lists::{definitive_tactic, itemize_list, write_list, ListFormatting, ListTac
             SeparatorPlace, SeparatorTactic};
 use rewrite::{Rewrite, RewriteContext};
 use shape::Shape;
-use utils::{colon_spaces, extra_offset, format_abi, format_mutability, last_line_width, mk_sp};
+use utils::{colon_spaces, extra_offset, first_line_width, format_abi, format_mutability,
+            last_line_width, mk_sp};
 
 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
 pub enum PathContext {
@@ -365,7 +366,8 @@ where
     let list_str = write_list(&item_vec, &fmt)?;
 
     let ty_shape = match context.config.indent_style() {
-        IndentStyle::Block => shape.block().block_indent(context.config.tab_spaces()),
+        // 4 = " -> "
+        IndentStyle::Block => shape.offset_left(4)?,
         IndentStyle::Visual => shape.block_left(4)?,
     };
     let output = match *output {
@@ -376,24 +378,23 @@ where
         FunctionRetTy::Default(..) => String::new(),
     };
 
-    let shape = shape.sub_width(output.len())?;
-    let extendable = !list_str.contains('\n') || list_str.is_empty();
+    let extendable = (!list_str.contains('\n') || list_str.is_empty()) && !output.contains("\n");
     let args = wrap_args_with_parens(
         context,
         &list_str,
         extendable,
-        shape,
+        shape.sub_width(first_line_width(&output))?,
         Shape::indented(offset, context.config),
     );
-    if last_line_width(&args) + output.len() > shape.width {
+    if last_line_width(&args) + first_line_width(&output) <= shape.width {
+        Some(format!("{}{}", args, output))
+    } else {
         Some(format!(
             "{}\n{}{}",
             args,
             offset.to_string(context.config),
             output.trim_left()
         ))
-    } else {
-        Some(format!("{}{}", args, output))
     }
 }
 

tests/source/issue-2164.rs

@@ -0,0 +1,4 @@
+// A stress test against code generated by bindgen.
+#[repr(C)]
+#[derive(Debug, Copy, Clone)]
+pub struct emacs_env_25 { pub size : isize , pub private_members : * mut emacs_env_private , pub make_global_ref : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , any_reference : emacs_value ) -> emacs_value > , pub free_global_ref : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , global_reference : emacs_value ) > , pub non_local_exit_check : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env ) -> emacs_funcall_exit > , pub non_local_exit_clear : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env ) > , pub non_local_exit_get : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , non_local_exit_symbol_out : * mut emacs_value , non_local_exit_data_out : * mut emacs_value ) -> emacs_funcall_exit > , pub non_local_exit_signal : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , non_local_exit_symbol : emacs_value , non_local_exit_data : emacs_value ) > , pub non_local_exit_throw : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , tag : emacs_value , value : emacs_value ) > , pub make_function : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , min_arity : isize , max_arity : isize , function : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , nargs : isize , args : * mut emacs_value , arg1 : * mut ::libc :: c_void ) -> emacs_value > , documentation : * const ::libc :: c_char , data : * mut ::libc :: c_void ) -> emacs_value > , pub funcall : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , function : emacs_value , nargs : isize , args : * mut emacs_value ) -> emacs_value > , pub intern : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , symbol_name : * const ::libc :: c_char ) -> emacs_value > , pub type_of : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , value : emacs_value ) -> emacs_value > , pub is_not_nil : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , value : emacs_value ) -> bool > , pub eq : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , a : emacs_value , b : emacs_value ) -> bool > , pub extract_integer : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , value : emacs_value ) -> intmax_t > , pub make_integer : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , value : intmax_t ) -> emacs_value > , pub extract_float : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , value : emacs_value ) -> f64 > , pub make_float : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , value : f64 ) -> emacs_value > , pub copy_string_contents : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , value : emacs_value , buffer : * mut ::libc :: c_char , size_inout : * mut isize ) -> bool > , pub make_string : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , contents : * const ::libc :: c_char , length : isize ) -> emacs_value > , pub make_user_ptr : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , fin : :: std :: option :: Option < unsafe extern "C" fn ( arg1 : * mut ::libc :: c_void ) > , ptr : * mut ::libc :: c_void ) -> emacs_value > , pub get_user_ptr : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , uptr : emacs_value ) -> * mut ::libc :: c_void > , pub set_user_ptr : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , uptr : emacs_value , ptr : * mut ::libc :: c_void ) > , pub get_user_finalizer : :: std :: option :: Option < unsafe extern "C" fn ( arg1 : * mut ::libc :: c_void , env : * mut emacs_env , uptr : emacs_value ) -> :: std :: option :: Option < unsafe extern "C" fn ( arg1 : * mut ::libc :: c_void , env : * mut emacs_env , uptr : emacs_value ) > > , pub set_user_finalizer : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , uptr : emacs_value , fin : :: std :: option :: Option < unsafe extern "C" fn ( arg1 : * mut ::libc :: c_void ) > ) > , pub vec_get : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , vec : emacs_value , i : isize ) -> emacs_value > , pub vec_set : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , vec : emacs_value , i : isize , val : emacs_value ) > , pub vec_size : :: std :: option :: Option < unsafe extern "C" fn ( env : * mut emacs_env , vec : emacs_value ) -> isize > , }

tests/target/big-impl-rfc.rs

@@ -78,8 +78,7 @@ impl<M, S, F, X> SubSelectDirect<M, S, F, X>
 where
     M: select::Selector,
     S: event::Stream,
-    F: for<'t> FnMut(transform::Api<'t, Stream<ContentStream<S>>>)
-        -> transform::Api<'t, X>,
+    F: for<'t> FnMut(transform::Api<'t, Stream<ContentStream<S>>>) -> transform::Api<'t, X>,
     X: event::Stream,
 {
 }

tests/target/issue-2164.rs

@@ -0,0 +1,132 @@
+// A stress test against code generated by bindgen.
+#[repr(C)]
+#[derive(Debug, Copy, Clone)]
+pub struct emacs_env_25 {
+    pub size: isize,
+    pub private_members: *mut emacs_env_private,
+    pub make_global_ref: ::std::option::Option<
+        unsafe extern "C" fn(env: *mut emacs_env, any_reference: emacs_value) -> emacs_value,
+    >,
+    pub free_global_ref: ::std::option::Option<
+        unsafe extern "C" fn(env: *mut emacs_env, global_reference: emacs_value),
+    >,
+    pub non_local_exit_check:
+        ::std::option::Option<unsafe extern "C" fn(env: *mut emacs_env) -> emacs_funcall_exit>,
+    pub non_local_exit_clear: ::std::option::Option<unsafe extern "C" fn(env: *mut emacs_env)>,
+    pub non_local_exit_get: ::std::option::Option<
+        unsafe extern "C" fn(
+            env: *mut emacs_env,
+            non_local_exit_symbol_out: *mut emacs_value,
+            non_local_exit_data_out: *mut emacs_value,
+        ) -> emacs_funcall_exit,
+    >,
+    pub non_local_exit_signal: ::std::option::Option<
+        unsafe extern "C" fn(
+            env: *mut emacs_env,
+            non_local_exit_symbol: emacs_value,
+            non_local_exit_data: emacs_value,
+        ),
+    >,
+    pub non_local_exit_throw: ::std::option::Option<
+        unsafe extern "C" fn(env: *mut emacs_env, tag: emacs_value, value: emacs_value),
+    >,
+    pub make_function: ::std::option::Option<
+        unsafe extern "C" fn(
+            env: *mut emacs_env,
+            min_arity: isize,
+            max_arity: isize,
+            function: ::std::option::Option<
+                unsafe extern "C" fn(
+                    env: *mut emacs_env,
+                    nargs: isize,
+                    args: *mut emacs_value,
+                    arg1: *mut ::libc::c_void,
+                ) -> emacs_value,
+            >,
+            documentation: *const ::libc::c_char,
+            data: *mut ::libc::c_void,
+        ) -> emacs_value,
+    >,
+    pub funcall: ::std::option::Option<
+        unsafe extern "C" fn(
+            env: *mut emacs_env,
+            function: emacs_value,
+            nargs: isize,
+            args: *mut emacs_value,
+        ) -> emacs_value,
+    >,
+    pub intern: ::std::option::Option<
+        unsafe extern "C" fn(env: *mut emacs_env, symbol_name: *const ::libc::c_char)
+            -> emacs_value,
+    >,
+    pub type_of: ::std::option::Option<
+        unsafe extern "C" fn(env: *mut emacs_env, value: emacs_value) -> emacs_value,
+    >,
+    pub is_not_nil: ::std::option::Option<
+        unsafe extern "C" fn(env: *mut emacs_env, value: emacs_value) -> bool,
+    >,
+    pub eq: ::std::option::Option<
+        unsafe extern "C" fn(env: *mut emacs_env, a: emacs_value, b: emacs_value) -> bool,
+    >,
+    pub extract_integer: ::std::option::Option<
+        unsafe extern "C" fn(env: *mut emacs_env, value: emacs_value) -> intmax_t,
+    >,
+    pub make_integer: ::std::option::Option<
+        unsafe extern "C" fn(env: *mut emacs_env, value: intmax_t) -> emacs_value,
+    >,
+    pub extract_float:
+        ::std::option::Option<unsafe extern "C" fn(env: *mut emacs_env, value: emacs_value) -> f64>,
+    pub make_float:
+        ::std::option::Option<unsafe extern "C" fn(env: *mut emacs_env, value: f64) -> emacs_value>,
+    pub copy_string_contents: ::std::option::Option<
+        unsafe extern "C" fn(
+            env: *mut emacs_env,
+            value: emacs_value,
+            buffer: *mut ::libc::c_char,
+            size_inout: *mut isize,
+        ) -> bool,
+    >,
+    pub make_string: ::std::option::Option<
+        unsafe extern "C" fn(env: *mut emacs_env, contents: *const ::libc::c_char, length: isize)
+            -> emacs_value,
+    >,
+    pub make_user_ptr: ::std::option::Option<
+        unsafe extern "C" fn(
+            env: *mut emacs_env,
+            fin: ::std::option::Option<
+                unsafe extern "C" fn(arg1: *mut ::libc::c_void),
+            >,
+            ptr: *mut ::libc::c_void,
+        ) -> emacs_value,
+    >,
+    pub get_user_ptr: ::std::option::Option<
+        unsafe extern "C" fn(env: *mut emacs_env, uptr: emacs_value) -> *mut ::libc::c_void,
+    >,
+    pub set_user_ptr: ::std::option::Option<
+        unsafe extern "C" fn(env: *mut emacs_env, uptr: emacs_value, ptr: *mut ::libc::c_void),
+    >,
+    pub get_user_finalizer: ::std::option::Option<
+        unsafe extern "C" fn(
+            arg1: *mut ::libc::c_void, env: *mut emacs_env, uptr: emacs_value
+        ) -> ::std::option::Option<
+            unsafe extern "C" fn(arg1: *mut ::libc::c_void, env: *mut emacs_env, uptr: emacs_value),
+        >,
+    >,
+    pub set_user_finalizer: ::std::option::Option<
+        unsafe extern "C" fn(
+            env: *mut emacs_env,
+            uptr: emacs_value,
+            fin: ::std::option::Option<
+                unsafe extern "C" fn(arg1: *mut ::libc::c_void),
+            >,
+        ),
+    >,
+    pub vec_get: ::std::option::Option<
+        unsafe extern "C" fn(env: *mut emacs_env, vec: emacs_value, i: isize) -> emacs_value,
+    >,
+    pub vec_set: ::std::option::Option<
+        unsafe extern "C" fn(env: *mut emacs_env, vec: emacs_value, i: isize, val: emacs_value),
+    >,
+    pub vec_size:
+        ::std::option::Option<unsafe extern "C" fn(env: *mut emacs_env, vec: emacs_value) -> isize>,
+}