From 97e92b35cc13c7afac277451db8997a2bf69678c Mon Sep 17 00:00:00 2001
From: Nick Cameron <ncameron@mozilla.com>
Date: Wed, 2 Sep 2015 14:11:19 +1200
Subject: [PATCH] Preserve some whitespace between struct fields etc.
---
src/items.rs | 4 +--
src/lists.rs | 66 +++++++++++++++++++++++++++++------------
tests/source/structs.rs | 28 +++++++++++++++++
tests/target/structs.rs | 18 +++++++++++
4 files changed, 94 insertions(+), 22 deletions(-)
diff --git a/src/items.rs b/src/items.rs
index 4d84a142045..36728ce84fa 100644
--- a/src/items.rs
+++ b/src/items.rs
@@ -632,13 +632,11 @@ impl<'a> FmtVisitor<'a> {
let break_line = !is_tuple || generics_str.contains('\n') ||
single_line_cost as usize + used_budget > self.config.max_width;
- if break_line {
+ let tactic = if break_line {
let indentation = make_indent(offset + self.config.tab_spaces);
result.push('\n');
result.push_str(&indentation);
- }
- let tactic = if break_line {
ListTactic::Vertical
} else {
ListTactic::Horizontal
diff --git a/src/lists.rs b/src/lists.rs
index 3b9bb3f4af2..6938e4eb4d4 100644
--- a/src/lists.rs
+++ b/src/lists.rs
@@ -70,9 +70,11 @@ impl<'a> ListFormatting<'a> {
pub struct ListItem {
pub pre_comment: Option<String>,
- // Item should include attributes and doc comments
+ // Item should include attributes and doc comments.
pub item: String,
pub post_comment: Option<String>,
+ // Whether there is extra whitespace before this item.
+ pub new_lines: bool,
}
impl ListItem {
@@ -86,7 +88,7 @@ impl ListItem {
}
pub fn from_str<S: Into<String>>(s: S) -> ListItem {
- ListItem { pre_comment: None, item: s.into(), post_comment: None }
+ ListItem { pre_comment: None, item: s.into(), post_comment: None, new_lines: false }
}
}
@@ -206,10 +208,8 @@ pub fn write_list<'b>(items: &[ListItem], formatting: &ListFormatting<'b>) -> St
// Post-comments
if tactic != ListTactic::Vertical && item.post_comment.is_some() {
- let formatted_comment = rewrite_comment(item.post_comment.as_ref().unwrap(),
- true,
- formatting.v_width,
- 0);
+ let comment = item.post_comment.as_ref().unwrap();
+ let formatted_comment = rewrite_comment(comment, true, formatting.v_width, 0);
result.push(' ');
result.push_str(&formatted_comment);
@@ -234,6 +234,10 @@ pub fn write_list<'b>(items: &[ListItem], formatting: &ListFormatting<'b>) -> St
result.push(' ');
result.push_str(&formatted_comment);
}
+
+ if !last && tactic == ListTactic::Vertical && item.new_lines {
+ result.push('\n');
+ }
}
result
@@ -264,13 +268,14 @@ impl<'a, T, I, F1, F2, F3> Iterator for ListItems<'a, I, F1, F2, F3>
let white_space: &[_] = &[' ', '\t'];
self.inner.next().map(|item| {
+ let mut new_lines = false;
// Pre-comment
let pre_snippet = self.codemap.span_to_snippet(codemap::mk_sp(self.prev_span_end,
(self.get_lo)(&item)))
.unwrap();
- let pre_snippet = pre_snippet.trim();
- let pre_comment = if !pre_snippet.is_empty() {
- Some(pre_snippet.to_owned())
+ let trimmed_pre_snippet = pre_snippet.trim();
+ let pre_comment = if !trimmed_pre_snippet.is_empty() {
+ Some(trimmed_pre_snippet.to_owned())
} else {
None
};
@@ -307,7 +312,7 @@ impl<'a, T, I, F1, F2, F3> Iterator for ListItems<'a, I, F1, F2, F3>
separator_index + 1)
}
// Potential *single* line comment.
- (_, Some(j)) => { j + 1 }
+ (_, Some(j)) => j + 1,
_ => post_snippet.len()
}
},
@@ -317,18 +322,40 @@ impl<'a, T, I, F1, F2, F3> Iterator for ListItems<'a, I, F1, F2, F3>
}
};
- // Cleanup post-comment: strip separators and whitespace.
- self.prev_span_end = (self.get_hi)(&item) + BytePos(comment_end as u32);
- let mut post_snippet = post_snippet[..comment_end].trim();
+ if !post_snippet.is_empty() && comment_end > 0 {
+ // Account for extra whitespace between items. This is fiddly
+ // because of the way we divide pre- and post- comments.
- if post_snippet.starts_with(',') {
- post_snippet = post_snippet[1..].trim_matches(white_space);
- } else if post_snippet.ends_with(",") {
- post_snippet = post_snippet[..(post_snippet.len() - 1)].trim_matches(white_space);
+ // Everything from the separator to the next item.
+ let test_snippet = &post_snippet[comment_end-1..];
+ let first_newline = test_snippet.find('\n').unwrap_or(test_snippet.len());
+ // From the end of the first line of comments.
+ let test_snippet = &test_snippet[first_newline..];
+ let first = test_snippet.find(|c: char| !c.is_whitespace())
+ .unwrap_or(test_snippet.len());
+ // From the end of the first line of comments to the next non-whitespace char.
+ let test_snippet = &test_snippet[..first];
+
+ if test_snippet.chars().filter(|c| c == &'\n').count() > 1 {
+ // There were multiple line breaks which got trimmed to nothing.
+ new_lines = true;
+ }
}
- let post_comment = if !post_snippet.is_empty() {
- Some(post_snippet.to_owned())
+ // Cleanup post-comment: strip separators and whitespace.
+ self.prev_span_end = (self.get_hi)(&item) + BytePos(comment_end as u32);
+ let post_snippet = post_snippet[..comment_end].trim();
+
+ let post_snippet_trimmed = if post_snippet.starts_with(',') {
+ post_snippet[1..].trim_matches(white_space)
+ } else if post_snippet.ends_with(",") {
+ post_snippet[..(post_snippet.len() - 1)].trim_matches(white_space)
+ } else {
+ post_snippet
+ };
+
+ let post_comment = if !post_snippet_trimmed.is_empty() {
+ Some(post_snippet_trimmed.to_owned())
} else {
None
};
@@ -337,6 +364,7 @@ impl<'a, T, I, F1, F2, F3> Iterator for ListItems<'a, I, F1, F2, F3>
pre_comment: pre_comment,
item: (self.get_item_string)(&item),
post_comment: post_comment,
+ new_lines: new_lines,
}
})
}
diff --git a/tests/source/structs.rs b/tests/source/structs.rs
index 68c7ff0df3c..76602a7a561 100644
--- a/tests/source/structs.rs
+++ b/tests/source/structs.rs
@@ -49,15 +49,43 @@ pub struct Foo<'a, Y: Baz>
}
struct Baz {
+
a: A, // Comment A
b: B, // Comment B
c: C, // Comment C
+
+}
+
+struct Baz {
+ a: A, // Comment A
+
+ b: B, // Comment B
+
+
+
+
+ c: C, // Comment C
+}
+
+struct Baz {
+
+ a: A,
+
+ b: B,
+ c: C,
+
+
+
+
+ d: D
+
}
struct Baz
{
// Comment A
a: A,
+
// Comment B
b: B,
// Comment C
diff --git a/tests/target/structs.rs b/tests/target/structs.rs
index 1f48c66b6a4..31e32a51b42 100644
--- a/tests/target/structs.rs
+++ b/tests/target/structs.rs
@@ -54,9 +54,27 @@ struct Baz {
c: C, // Comment C
}
+struct Baz {
+ a: A, // Comment A
+
+ b: B, // Comment B
+
+ c: C, // Comment C
+}
+
+struct Baz {
+ a: A,
+
+ b: B,
+ c: C,
+
+ d: D,
+}
+
struct Baz {
// Comment A
a: A,
+
// Comment B
b: B,
// Comment C