refactor: Right align line numbers

Author: Muscraft

examples/multislice.svg

@@ -533,6 +533,7 @@ impl Renderer {
                 buffer,
                 width_offset,
                 code_offset,
+                max_line_num_len,
                 margin,
             );
 
@@ -605,6 +606,7 @@ impl Renderer {
                             last_buffer_line_num,
                             width_offset,
                             code_offset,
+                            max_line_num_len,
                             margin,
                         );
 
@@ -646,6 +648,7 @@ impl Renderer {
         buffer: &mut StyledBuffer,
         width_offset: usize,
         code_offset: usize,
+        max_line_num_len: usize,
         margin: Margin,
     ) -> Vec<(usize, ElementStyle)> {
         // Draw:
@@ -684,6 +687,7 @@ impl Renderer {
             line_offset,
             width_offset,
             code_offset,
+            max_line_num_len,
             margin,
         );
 
@@ -1185,6 +1189,7 @@ impl Renderer {
         line_offset: usize,
         width_offset: usize,
         code_offset: usize,
+        max_line_num_len: usize,
         margin: Margin,
     ) {
         // Tabs are assumed to have been replaced by spaces in calling code.
@@ -1228,7 +1233,7 @@ impl Renderer {
         buffer.puts(
             line_offset,
             0,
-            &self.maybe_anonymized(line_index),
+            &format!("{:>max_line_num_len$}", self.maybe_anonymized(line_index)),
             ElementStyle::LineNumber,
         );
 

src/renderer/mod.rs

@@ -102,11 +102,13 @@ impl Message<'_> {
 fn newline_count(body: &str) -> usize {
     #[cfg(feature = "simd")]
     {
-        memchr::memchr_iter(b'\n', body.as_bytes()).count()
+        memchr::memchr_iter(b'\n', body.as_bytes())
+            .count()
+            .saturating_sub(1)
     }
     #[cfg(not(feature = "simd"))]
     {
-        body.lines().count()
+        body.lines().count().saturating_sub(1)
     }
 }
 

src/snippet.rs

@@ -149,7 +149,7 @@ error:
      |
     ::: file2.rs
      |
-2    | This is slice 2
+   2 | This is slice 2
 "#]];
     let renderer = Renderer::plain();
     assert_data_eq!(renderer.render(input), expected);

tests/fixtures/color/issue_9.svg

@@ -685,15 +685,15 @@ fn foo() {
 error: foo
   --> test.rs:3:6
    |
-3  |      X0 Y0 Z0
+ 3 |      X0 Y0 Z0
    |  _______^
-4  | |    X1 Y1 Z1
+ 4 | |    X1 Y1 Z1
    | | ____^____-
    | ||____|
    |  |    `X` is a good letter
-5  |  | 1
-6  |  | 2
-7  |  | 3
+ 5 |  | 1
+ 6 |  | 2
+ 7 |  | 3
 ...   |
 15 |  |   X2 Y2 Z2
 16 |  |   X3 Y3 Z3
@@ -739,15 +739,15 @@ fn foo() {
 error: foo
   --> test.rs:3:6
    |
-3  |      X0 Y0 Z0
+ 3 |      X0 Y0 Z0
    |  _______^
-4  | |  1
-5  | |  2
-6  | |  3
-7  | |    X1 Y1 Z1
+ 4 | |  1
+ 5 | |  2
+ 6 | |  3
+ 7 | |    X1 Y1 Z1
    | | _________-
-8  | || 4
-9  | || 5
+ 8 | || 4
+ 9 | || 5
 10 | || 6
 11 | ||   X2 Y2 Z2
    | ||__________- `Z` is a good letter too