Fix bad line printing for parse errors

The code that extracted lines from partially-parsed files
was broken.

Closes #1848

2 files changed, 6 insertions, 12 deletions

diff --git a/src/comp/driver/diagnostic.rs b/src/comp/driver/diagnostic.rs
index a0f97842546..8f0570a4349 100644
--- a/src/comp/driver/diagnostic.rs
+++ b/src/comp/driver/diagnostic.rs
@@ -204,8 +204,7 @@ fn highlight_lines(cm: codemap::codemap, sp: span,
     // Print the offending lines
     for line: uint in display_lines {
         io::stderr().write_str(#fmt["%s:%u ", fm.name, line + 1u]);
-        let s = codemap::get_line(fm, line as int);
-        if !str::ends_with(s, "\n") { s += "\n"; }
+        let s = codemap::get_line(fm, line as int) + "\n";
         io::stderr().write_str(s);
     }
     if elided {
diff --git a/src/comp/syntax/codemap.rs b/src/comp/syntax/codemap.rs
index 03ade9a6931..7e153839448 100644
--- a/src/comp/syntax/codemap.rs
+++ b/src/comp/syntax/codemap.rs
@@ -157,16 +157,11 @@ fn span_to_lines(sp: span, cm: codemap::codemap) -> @file_lines {
 
 fn get_line(fm: filemap, line: int) -> str unsafe {
     let begin: uint = fm.lines[line].byte - fm.start_pos.byte;
-    let end: uint;
-    if line as uint < vec::len(fm.lines) - 1u {
-        end = fm.lines[line + 1].byte - fm.start_pos.byte;
-        ret str::unsafe::slice_bytes(*fm.src, begin, end);
-    } else {
-        // If we're not done parsing the file, we're at the limit of what's
-        // parsed. If we just slice the rest of the string, we'll print out
-        // the remainder of the file, which is undesirable.
-        ret str::splitn_char(*fm.src, '\n', 1u)[0];
-    }
+    let end = alt str::byte_index(*fm.src, '\n' as u8, begin) {
+      some(e) { e }
+      none { str::len(*fm.src) }
+    };
+    str::unsafe::slice_bytes(*fm.src, begin, end)
 }
 
 fn lookup_byte_offset(cm: codemap::codemap, chpos: uint)