Fix #4654 - version gated consistent format of struct post-comments in new line - with and without trailing comma

Author: davidBar-On

src/attr.rs

@@ -122,6 +122,7 @@ fn format_derive(
                 context.snippet_provider.span_after(attr.span, "("),
                 attr.span.hi(),
                 false,
+                context.config.version(),
             );
 
             Some(items)

src/closures.rs

@@ -283,6 +283,7 @@ fn rewrite_closure_fn_decl(
         context.snippet_provider.span_after(span, "|"),
         body.span.lo(),
         false,
+        context.config.version(),
     );
     let item_vec = param_items.collect::<Vec<_>>();
     // 1 = space between parameters and return type.

src/expr.rs

@@ -1623,6 +1623,7 @@ fn rewrite_struct_lit<'a>(
             body_lo,
             span.hi(),
             false,
+            context.config.version(),
         );
         let item_vec = items.collect::<Vec<_>>();
 
@@ -1773,6 +1774,7 @@ fn rewrite_tuple_in_visual_indent_style<'a, T: 'a + IntoOverflowableItem<'a>>(
         list_lo,
         span.hi() - BytePos(1),
         false,
+        context.config.version(),
     );
     let item_vec: Vec<_> = items.collect();
     let tactic = definitive_tactic(

src/imports.rs

@@ -472,6 +472,7 @@ impl UseTree {
                     context.snippet_provider.span_after(a.span, "{"),
                     a.span.hi(),
                     false,
+                    context.config.version(),
                 );
 
                 // in case of a global path and the nested list starts at the root,

src/items.rs

@@ -381,8 +381,8 @@ impl<'a> FmtVisitor<'a> {
             return None;
         }
 
-        let res = Stmt::from_ast_node(block.stmts.first()?, true)
-            .rewrite(&self.get_context(), self.shape())?;
+        let res =
+            Stmt::from_ast_node(block.stmts.first()?, true).rewrite(&context, self.shape())?;
 
         let width = self.block_indent.width() + fn_str.len() + res.len() + 5;
         if !res.contains('\n') && width <= self.config.max_width() {
@@ -441,7 +441,12 @@ impl<'a> FmtVisitor<'a> {
 
         self.last_pos = body_start;
 
-        match self.format_variant_list(enum_def, body_start, span.hi()) {
+        match self.format_variant_list(
+            enum_def,
+            body_start,
+            span.hi(),
+            self.get_context().config.version(),
+        ) {
             Some(ref s) if enum_def.variants.is_empty() => self.push_str(s),
             rw => {
                 self.push_rewrite(mk_sp(body_start, span.hi()), rw);
@@ -456,6 +461,7 @@ impl<'a> FmtVisitor<'a> {
         enum_def: &ast::EnumDef,
         body_lo: BytePos,
         body_hi: BytePos,
+        version: Version,
     ) -> Option<String> {
         if enum_def.variants.is_empty() {
             let mut buffer = String::with_capacity(128);
@@ -510,6 +516,7 @@ impl<'a> FmtVisitor<'a> {
                 body_lo,
                 body_hi,
                 false,
+                version,
             )
             .collect()
         };
@@ -2599,6 +2606,7 @@ fn rewrite_params(
         span.lo(),
         span.hi(),
         false,
+        context.config.version(),
     )
     .collect();
 
@@ -2868,6 +2876,7 @@ fn rewrite_bounds_on_where_clause(
         span_start,
         span_end,
         false,
+        context.config.version(),
     );
     let comma_tactic = if where_clause_option.suppress_comma || force_single_line {
         SeparatorTactic::Never
@@ -2947,6 +2956,7 @@ fn rewrite_where_clause(
         span_start,
         span_end,
         false,
+        context.config.version(),
     );
     let item_vec = items.collect::<Vec<_>>();
     // FIXME: we don't need to collect here

src/lists.rs

@@ -7,7 +7,7 @@ use rustc_span::BytePos;
 
 use crate::comment::{find_comment_end, rewrite_comment, FindUncommented};
 use crate::config::lists::*;
-use crate::config::{Config, IndentStyle};
+use crate::config::{Config, IndentStyle, Version};
 use crate::rewrite::RewriteContext;
 use crate::shape::{Indent, Shape};
 use crate::utils::{
@@ -570,6 +570,7 @@ where
     terminator: &'a str,
     separator: &'a str,
     leave_last: bool,
+    version: Version,
 }
 
 pub(crate) fn extract_pre_comment(pre_snippet: &str) -> (Option<String>, ListItemCommentStyle) {
@@ -612,11 +613,25 @@ pub(crate) fn extract_post_comment(
     comment_end: usize,
     separator: &str,
     is_last: bool,
+    version: Version,
 ) -> Option<String> {
     let white_space: &[_] = &[' ', '\t'];
 
     // Cleanup post-comment: strip separators and whitespace.
-    let post_snippet = post_snippet[..comment_end].trim();
+    let post_snippet = if version == Version::One {
+        post_snippet[..comment_end].trim()
+    } else {
+        // If trimmed string starts with comment - preserve leading new-line.
+        let post_snippet_start_trimmed = post_snippet[..comment_end].trim_start();
+        if post_snippet_start_trimmed.starts_with("//")
+            || post_snippet_start_trimmed.starts_with("/*")
+        {
+            post_snippet[..comment_end].trim_matches(white_space)
+        } else {
+            post_snippet_start_trimmed
+        }
+        .trim_end()
+    };
 
     let last_inline_comment_ends_with_separator = if is_last {
         if let Some(line) = post_snippet.lines().last() {
@@ -767,8 +782,13 @@ where
             let comment_end =
                 get_comment_end(post_snippet, self.separator, self.terminator, is_last);
             let new_lines = has_extra_newline(post_snippet, comment_end);
-            let post_comment =
-                extract_post_comment(post_snippet, comment_end, self.separator, is_last);
+            let post_comment = extract_post_comment(
+                post_snippet,
+                comment_end,
+                self.separator,
+                is_last,
+                self.version,
+            );
 
             self.prev_span_end = (self.get_hi)(&item) + BytePos(comment_end as u32);
 
@@ -800,6 +820,7 @@ pub(crate) fn itemize_list<'a, T, I, F1, F2, F3>(
     prev_span_end: BytePos,
     next_span_start: BytePos,
     leave_last: bool,
+    version: Version,
 ) -> ListItems<'a, I, F1, F2, F3>
 where
     I: Iterator<Item = T>,
@@ -818,6 +839,7 @@ where
         terminator,
         separator,
         leave_last,
+        version,
     }
 }
 

src/macros.rs

@@ -438,6 +438,7 @@ pub(crate) fn rewrite_macro_def(
         context.snippet_provider.span_after(span, "{"),
         span.hi(),
         false,
+        context.config.version(),
     )
     .collect::<Vec<_>>();
 

src/matches.rs

@@ -204,6 +204,7 @@ fn rewrite_match_arms(
         open_brace_pos,
         span.hi(),
         false,
+        context.config.version(),
     );
     let arms_vec: Vec<_> = items.collect();
     // We will add/remove commas inside `arm.rewrite()`, and hence no separator here.

src/overflow.rs

@@ -587,7 +587,7 @@ impl<'a> Context<'a> {
         tactic
     }
 
-    fn rewrite_items(&self) -> Option<(bool, String)> {
+    fn rewrite_items(&self, version: Version) -> Option<(bool, String)> {
         let span = self.items_span();
         let items = itemize_list(
             self.context.snippet_provider,
@@ -600,6 +600,7 @@ impl<'a> Context<'a> {
             span.lo(),
             span.hi(),
             true,
+            version,
         );
         let mut list_items: Vec<_> = items.collect();
 
@@ -682,7 +683,7 @@ impl<'a> Context<'a> {
     }
 
     fn rewrite(&self, shape: Shape) -> Option<String> {
-        let (extendable, items_str) = self.rewrite_items()?;
+        let (extendable, items_str) = self.rewrite_items(self.context.config.version())?;
 
         // If we are using visual indent style and failed to format, retry with block indent.
         if !self.context.use_block_indent()

src/patterns.rs

@@ -308,6 +308,7 @@ fn rewrite_struct_pat(
         context.snippet_provider.span_after(span, "{"),
         span.hi(),
         false,
+        context.config.version(),
     );
     let item_vec = items.collect::<Vec<_>>();
 
@@ -516,6 +517,7 @@ fn count_wildcard_suffix_len(
         context.snippet_provider.span_after(span, "("),
         span.hi() - BytePos(1),
         false,
+        context.config.version(),
     )
     .collect();
 

src/reorder.rs

@@ -103,6 +103,7 @@ fn rewrite_reorderable_or_regroupable_items(
                 span.lo(),
                 span.hi(),
                 false,
+                context.config.version(),
             );
             for (item, list_item) in normalized_items.iter_mut().zip(list_items) {
                 item.list_item = Some(list_item.clone());
@@ -155,6 +156,7 @@ fn rewrite_reorderable_or_regroupable_items(
                 span.lo(),
                 span.hi(),
                 false,
+                context.config.version(),
             );
 
             let mut item_pair_vec: Vec<_> = list_items.zip(reorderable_items.iter()).collect();

src/types.rs

@@ -351,6 +351,7 @@ where
             list_lo,
             span.hi(),
             false,
+            context.config.version(),
         );
 
         let item_vec: Vec<_> = items.collect();

src/vertical.rs

@@ -233,6 +233,7 @@ fn rewrite_aligned_items_inner<T: AlignedItem>(
         span.lo(),
         span.hi(),
         false,
+        context.config.version(),
     )
     .collect::<Vec<_>>();