From: Seiichi Uchida <seuchida@gmail.com>
Date: Wed, 7 Mar 2018 10:29:42 +0000 (+0900)
Subject: Use Option<SeparatorTactic> over bool to control trailing comma
X-Git-Url: https://git.lizzy.rs/?a=commitdiff_plain;h=6ba7c34433ef62f25e566fe2f8729a674d57aa00;p=rust.git

Use Option<SeparatorTactic> over bool to control trailing comma
---

diff --git a/src/expr.rs b/src/expr.rs
index 647b81830d4..a38e9b0b8f8 100644
--- a/src/expr.rs
+++ b/src/expr.rs
@@ -1936,9 +1936,13 @@ pub fn rewrite_call(
         span,
         context.config.width_heuristics().fn_call_width,
         if context.inside_macro {
-            span_ends_with_comma(context, span)
+            if span_ends_with_comma(context, span) {
+                Some(SeparatorTactic::Always)
+            } else {
+                Some(SeparatorTactic::Never)
+            }
         } else {
-            false
+            None
         },
     )
 }
@@ -2422,10 +2426,18 @@ pub fn rewrite_tuple<'a, T>(
     debug!("rewrite_tuple {:?}", shape);
     if context.use_block_indent() {
         // We use the same rule as function calls for rewriting tuples.
-        let force_trailing_comma = if context.inside_macro {
-            span_ends_with_comma(context, span)
+        let force_tactic = if context.inside_macro {
+            if span_ends_with_comma(context, span) {
+                Some(SeparatorTactic::Always)
+            } else {
+                Some(SeparatorTactic::Never)
+            }
         } else {
-            items.len() == 1
+            if items.len() == 1 {
+                Some(SeparatorTactic::Always)
+            } else {
+                None
+            }
         };
         overflow::rewrite_with_parens(
             context,
@@ -2434,7 +2446,7 @@ pub fn rewrite_tuple<'a, T>(
             shape,
             span,
             context.config.width_heuristics().fn_call_width,
-            force_trailing_comma,
+            force_tactic,
         )
     } else {
         rewrite_tuple_in_visual_indent_style(context, items, span, shape)
diff --git a/src/items.rs b/src/items.rs
index 23f96358d8e..d3286864ce7 100644
--- a/src/items.rs
+++ b/src/items.rs
@@ -1290,7 +1290,7 @@ fn format_tuple_struct(
             shape,
             span,
             context.config.width_heuristics().fn_call_width,
-            false,
+            None,
         )?;
     }
 
diff --git a/src/macros.rs b/src/macros.rs
index db79fb9d576..bb870e589ee 100644
--- a/src/macros.rs
+++ b/src/macros.rs
@@ -233,7 +233,11 @@ pub fn rewrite_macro(
                 shape,
                 mac.span,
                 context.config.width_heuristics().fn_call_width,
-                trailing_comma,
+                if trailing_comma {
+                    Some(SeparatorTactic::Always)
+                } else {
+                    Some(SeparatorTactic::Never)
+                },
             ).map(|rw| match position {
                 MacroPosition::Item => format!("{};", rw),
                 _ => rw,
diff --git a/src/overflow.rs b/src/overflow.rs
index b5634def086..294c257d31f 100644
--- a/src/overflow.rs
+++ b/src/overflow.rs
@@ -33,7 +33,7 @@ pub fn rewrite_with_parens<T>(
     shape: Shape,
     span: Span,
     item_max_width: usize,
-    force_trailing_comma: bool,
+    force_separator_tactic: Option<SeparatorTactic>,
 ) -> Option<String>
 where
     T: Rewrite + ToExpr + Spanned,
@@ -47,7 +47,7 @@ pub fn rewrite_with_parens<T>(
         "(",
         ")",
         item_max_width,
-        force_trailing_comma,
+        force_separator_tactic,
     ).rewrite(shape)
 }
 
@@ -70,7 +70,7 @@ pub fn rewrite_with_angle_brackets<T>(
         "<",
         ">",
         context.config.max_width(),
-        false,
+        None,
     ).rewrite(shape)
 }
 
@@ -85,7 +85,7 @@ struct Context<'a, T: 'a> {
     span: Span,
     item_max_width: usize,
     one_line_width: usize,
-    force_trailing_comma: bool,
+    force_separator_tactic: Option<SeparatorTactic>,
 }
 
 impl<'a, T: 'a + Rewrite + ToExpr + Spanned> Context<'a, T> {
@@ -98,7 +98,7 @@ pub fn new(
         prefix: &'static str,
         suffix: &'static str,
         item_max_width: usize,
-        force_trailing_comma: bool,
+        force_separator_tactic: Option<SeparatorTactic>,
     ) -> Context<'a, T> {
         // 2 = `( `, 1 = `(`
         let paren_overhead = if context.config.spaces_within_parens_and_brackets() {
@@ -134,7 +134,7 @@ pub fn new(
             suffix,
             item_max_width,
             one_line_width,
-            force_trailing_comma,
+            force_separator_tactic,
         }
     }
 
@@ -336,9 +336,9 @@ fn rewrite_items(&self) -> Option<(bool, String)> {
         let fmt = ListFormatting {
             tactic,
             separator: ",",
-            trailing_separator: if self.force_trailing_comma {
-                SeparatorTactic::Always
-            } else if self.context.inside_macro || !self.context.use_block_indent() {
+            trailing_separator: if let Some(tactic) = self.force_separator_tactic {
+                tactic
+            } else if !self.context.use_block_indent() {
                 SeparatorTactic::Never
             } else {
                 self.context.config.trailing_comma()
diff --git a/src/patterns.rs b/src/patterns.rs
index c6cacc8bff5..54b7e0f9a4c 100644
--- a/src/patterns.rs
+++ b/src/patterns.rs
@@ -343,7 +343,11 @@ fn rewrite_tuple_pat(
         shape,
         span,
         context.config.max_width(),
-        add_comma,
+        if add_comma {
+            Some(SeparatorTactic::Always)
+        } else {
+            None
+        },
     )
 }