Skip to content

Commit

Permalink
Handle more possible comment position for if else
Browse files Browse the repository at this point in the history 
Extended the test with the new possiblecomment positions
  • Loading branch information
@DarkDrek
DarkDrek committed Jan 12, 2016
1 parent b0eb0f5 commit 4da91e7
Show file tree
Hide file tree
Showing 4 changed files with 144 additions and 30 deletions.
91 changes: 64 additions & 27 deletions src/expr.rs
View file
Expand Up @@ -13,14 +13,15 @@ use std::borrow::Borrow;
use std::mem::swap;
use std::ops::Deref;
use std::iter::ExactSizeIterator;
use std::fmt::Write;

use {Indent, Spanned};
use rewrite::{Rewrite, RewriteContext};
use lists::{write_list, itemize_list, ListFormatting, SeparatorTactic, ListTactic,
DefinitiveListTactic, definitive_tactic, ListItem, format_fn_args};
use string::{StringFormat, rewrite_string};
use utils::{span_after, extra_offset, last_line_width, wrap_str, binary_search, first_line_width,
semicolon_for_stmt};
use utils::{span_after, span_before, extra_offset, last_line_width, wrap_str, binary_search,
first_line_width, semicolon_for_stmt};
use visitor::FmtVisitor;
use config::{Config, StructLitStyle, MultilineStyle};
use comment::{FindUncommented, rewrite_comment, contains_comment, recover_comment_removed};
Expand Down Expand Up @@ -101,6 +102,7 @@ impl Rewrite for ast::Expr {
cond,
if_block,
else_block.as_ref().map(|e| &**e),
self.span,
None,
width,
offset,
Expand All @@ -111,6 +113,7 @@ impl Rewrite for ast::Expr {
cond,
if_block,
else_block.as_ref().map(|e| &**e),
self.span,
Some(pat),
width,
offset,
Expand Down Expand Up @@ -605,12 +608,33 @@ fn rewrite_label(label: Option<ast::Ident>) -> String {
}
}

fn extract_comment(span: Span,
context: &RewriteContext,
offset: Indent,
width: usize)
-> Option<String> {
let comment_str = context.snippet(span);
if contains_comment(&comment_str) {
let comment = try_opt!(rewrite_comment(comment_str.trim(),
false,
width,
offset,
context.config));
Some(format!("\n{indent}{}\n{indent}",
comment,
indent = offset.to_string(context.config)))
} else {
None
}
}

// Rewrites if-else blocks. If let Some(_) = pat, the expression is
// treated as an if-let-else expression.
fn rewrite_if_else(context: &RewriteContext,
cond: &ast::Expr,
if_block: &ast::Block,
else_block_opt: Option<&ast::Expr>,
span: Span,
pat: Option<&ast::Pat>,
width: usize,
offset: Indent,
Expand All @@ -635,7 +659,22 @@ fn rewrite_if_else(context: &RewriteContext,
}

let if_block_string = try_opt!(if_block.rewrite(context, width, offset));
let mut result = format!("if {} {}", pat_expr_string, if_block_string);

let between_if_cond = mk_sp(span_after(span, "if", context.codemap),
pat.map_or(cond.span.lo,
|_| span_before(span, "let", context.codemap)));
let between_if_cond_comment = extract_comment(between_if_cond, &context, offset, width);

let after_cond_comment = extract_comment(mk_sp(cond.span.hi, if_block.span.lo),
context,
offset,
width);

let mut result = format!("if{}{}{}{}",
between_if_cond_comment.as_ref().map_or(" ", |str| &**str),
pat_expr_string,
after_cond_comment.as_ref().map_or(" ", |str| &**str),
if_block_string);

if let Some(else_block) = else_block_opt {
let rewrite = match else_block.node {
Expand All @@ -646,6 +685,7 @@ fn rewrite_if_else(context: &RewriteContext,
cond,
if_block,
else_block.as_ref().map(|e| &**e),
mk_sp(span_after(span, "else", context.codemap), span.hi),
Some(pat),
width,
offset,
Expand All @@ -656,6 +696,7 @@ fn rewrite_if_else(context: &RewriteContext,
cond,
if_block,
else_block.as_ref().map(|e| &**e),
mk_sp(span_after(span, "else", context.codemap), span.hi),
None,
width,
offset,
Expand All @@ -664,30 +705,26 @@ fn rewrite_if_else(context: &RewriteContext,
_ => else_block.rewrite(context, width, offset),
};

let snippet = context.codemap
.span_to_snippet(mk_sp(if_block.span.hi, else_block.span.lo))
.unwrap();
// Preserve comments that are between the if and else block
if contains_comment(&snippet) {
let close_pos = try_opt!(snippet.find_uncommented("else"));
let trimmed = &snippet[..close_pos].trim();
let comment_str = format!("{}{}",
offset.to_string(context.config),
try_opt!(rewrite_comment(trimmed,
false,
width,
offset,
context.config)),
);
let else_str = format!("{}else ", offset.to_string(context.config));

result.push('\n');
result.push_str(&comment_str);
result.push('\n');
result.push_str(&else_str);
} else {
result.push_str(" else ");
}
let between_if_else_block = mk_sp(if_block.span.hi,
span_before(mk_sp(if_block.span.hi, else_block.span.lo),
"else",
context.codemap));
let between_if_else_block_comment = extract_comment(between_if_else_block,
&context,
offset,
width);

let after_else = mk_sp(span_after(mk_sp(if_block.span.hi, else_block.span.lo),
"else",
context.codemap),
else_block.span.lo);
let after_else_comment = extract_comment(after_else, &context, offset, width);

try_opt!(write!(&mut result,
"{}else{}",
between_if_else_block_comment.as_ref().map_or(" ", |str| &**str),
after_else_comment.as_ref().map_or(" ", |str| &**str))
.ok());
result.push_str(&&try_opt!(rewrite));
}

Expand Down
8 changes: 8 additions & 0 deletions src/utils.rs
View file
Expand Up @@ -38,6 +38,14 @@ pub fn span_after(original: Span, needle: &str, codemap: &CodeMap) -> BytePos {
original.lo + BytePos(offset as u32)
}

#[inline]
pub fn span_before(original: Span, needle: &str, codemap: &CodeMap) -> BytePos {
let snippet = codemap.span_to_snippet(original).unwrap();
let offset = snippet.find_uncommented(needle).unwrap();

original.lo + BytePos(offset as u32)
}

#[inline]
pub fn span_after_last(original: Span, needle: &str, codemap: &CodeMap) -> BytePos {
let snippet = codemap.span_to_snippet(original).unwrap();
Expand Down
37 changes: 37 additions & 0 deletions tests/source/issue-447.rs
View file
@@ -0,0 +1,37 @@
fn main() {
if /* shouldn't be dropped
shouldn't be dropped */

cond /* shouldn't be dropped
shouldn't be dropped */

{
} /* shouldn't be dropped
shouldn't be dropped */

else /* shouldn't be dropped
shouldn't be dropped */

if /* shouldn't be dropped
shouldn't be dropped */

cond /* shouldn't be dropped
shouldn't be dropped */

{
} /* shouldn't be dropped
shouldn't be dropped */

else /* shouldn't be dropped
shouldn't be dropped */

{
}

if /* shouldn't be dropped
shouldn't be dropped */
let Some(x) = y/* shouldn't be dropped
shouldn't be dropped */
{
}
}
38 changes: 35 additions & 3 deletions tests/target/issue-447.rs
View file
@@ -1,7 +1,39 @@
fn main() {
if cond {
if
// shouldn't be dropped
// shouldn't be dropped
cond
// shouldn't be dropped
// shouldn't be dropped
{
}
// This shouldn't be dropped
else {
// shouldn't be dropped
// shouldn't be dropped
else
// shouldn't be dropped
// shouldn't be dropped
if
// shouldn't be dropped
// shouldn't be dropped
cond
// shouldn't be dropped
// shouldn't be dropped
{
}
// shouldn't be dropped
// shouldn't be dropped
else
// shouldn't be dropped
// shouldn't be dropped
{
}

if
// shouldn't be dropped
// shouldn't be dropped
let Some(x) = y
// shouldn't be dropped
// shouldn't be dropped
{
}
}

0 comments on commit 4da91e7

Please sign in to comment.