X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=src%2Fshape.rs;h=12a911a19315a583d9a62e733758567725cf7ad9;hb=fc3ea494ac73aee782a903849c09bb011fe18e37;hp=fffbe2b9913ea5a392c81813e1e2eff0b21557ed;hpb=9754bcb535fa84c000fe78cb91b30c3f661fc849;p=rust.git

diff --git a/src/shape.rs b/src/shape.rs
index fffbe2b9913..12a911a1931 100644
--- a/src/shape.rs
+++ b/src/shape.rs
@@ -9,6 +9,7 @@
 // except according to those terms.
 
 use std::borrow::Cow;
+use std::cmp::min;
 use std::ops::{Add, Sub};
 
 use Config;
@@ -22,15 +23,16 @@ pub struct Indent {
     pub alignment: usize,
 }
 
-// INDENT_BUFFER.len() = 80
+// INDENT_BUFFER.len() = 81
 const INDENT_BUFFER_LEN: usize = 80;
 const INDENT_BUFFER: &str =
-    "                                                                                ";
+    "\n                                                                                ";
+
 impl Indent {
     pub fn new(block_indent: usize, alignment: usize) -> Indent {
         Indent {
-            block_indent: block_indent,
-            alignment: alignment,
+            block_indent,
+            alignment,
         }
     }
 
@@ -74,16 +76,27 @@ pub fn width(&self) -> usize {
     }
 
     pub fn to_string(&self, config: &Config) -> Cow<'static, str> {
+        self.to_string_inner(config, 1)
+    }
+
+    pub fn to_string_with_newline(&self, config: &Config) -> Cow<'static, str> {
+        self.to_string_inner(config, 0)
+    }
+
+    fn to_string_inner(&self, config: &Config, offset: usize) -> Cow<'static, str> {
         let (num_tabs, num_spaces) = if config.hard_tabs() {
             (self.block_indent / config.tab_spaces(), self.alignment)
         } else {
             (0, self.width())
         };
         let num_chars = num_tabs + num_spaces;
-        if num_tabs == 0 && num_chars <= INDENT_BUFFER_LEN {
-            Cow::from(&INDENT_BUFFER[0..num_chars])
+        if num_tabs == 0 && num_chars + offset <= INDENT_BUFFER_LEN {
+            Cow::from(&INDENT_BUFFER[offset..num_chars + 1])
         } else {
-            let mut indent = String::with_capacity(num_chars);
+            let mut indent = String::with_capacity(num_chars + if offset == 0 { 1 } else { 0 });
+            if offset == 0 {
+                indent.push('\n');
+            }
             for _ in 0..num_tabs {
                 indent.push('\t')
             }
@@ -161,38 +174,27 @@ impl Shape {
     //        |<--->|    width
     pub fn legacy(width: usize, indent: Indent) -> Shape {
         Shape {
-            width: width,
-            indent: indent,
+            width,
+            indent,
             offset: indent.alignment,
         }
     }
 
     pub fn indented(indent: Indent, config: &Config) -> Shape {
         Shape {
-            width: config.max_width().checked_sub(indent.width()).unwrap_or(0),
-            indent: indent,
+            width: config.max_width().saturating_sub(indent.width()),
+            indent,
             offset: indent.alignment,
         }
     }
 
     pub fn with_max_width(&self, config: &Config) -> Shape {
         Shape {
-            width: config
-                .max_width()
-                .checked_sub(self.indent.width())
-                .unwrap_or(0),
+            width: config.max_width().saturating_sub(self.indent.width()),
             ..*self
         }
     }
 
-    pub fn offset(width: usize, indent: Indent, offset: usize) -> Shape {
-        Shape {
-            width: width,
-            indent: indent,
-            offset: offset,
-        }
-    }
-
     pub fn visual_indent(&self, extra_width: usize) -> Shape {
         let alignment = self.offset + extra_width;
         Shape {
@@ -262,8 +264,21 @@ pub fn used_width(&self) -> usize {
     pub fn rhs_overhead(&self, config: &Config) -> usize {
         config
             .max_width()
-            .checked_sub(self.used_width() + self.width)
-            .unwrap_or(0)
+            .saturating_sub(self.used_width() + self.width)
+    }
+
+    pub fn comment(&self, config: &Config) -> Shape {
+        let width = min(
+            self.width,
+            config.comment_width().saturating_sub(self.indent.width()),
+        );
+        Shape { width, ..*self }
+    }
+
+    pub fn to_string_with_newline(&self, config: &Config) -> Cow<'static, str> {
+        let mut offset_indent = self.indent;
+        offset_indent.alignment = self.offset;
+        offset_indent.to_string_inner(config, 0)
     }
 }