From ed36470af1c71a254bbe535bf70220aa27370f89 Mon Sep 17 00:00:00 2001
From: Andrew Kelley <andrew@ziglang.org>
Date: Thu, 23 May 2024 11:10:41 -0700
Subject: [PATCH] std.Progress: truncate trailing newline

---
 lib/std/Progress.zig | 50 ++++++++++++++++++++------------------------
 1 file changed, 23 insertions(+), 27 deletions(-)

diff --git a/lib/std/Progress.zig b/lib/std/Progress.zig
index 0e625f4785d046495689bf55d60889230fb30d35..3703b1f8d1e3cc75dde8bd68f67732219bc443a2 100644
--- a/lib/std/Progress.zig
+++ b/lib/std/Progress.zig
@@ -367,19 +367,7 @@ fn clearTerminal() void {
     buf[i..][0..start_sync.len].* = start_sync.*;
     i += start_sync.len;
 
-    const prev_nl_n = global_progress.newline_count;
-    if (prev_nl_n > 0) {
-        global_progress.newline_count = 0;
-        buf[i] = '\r';
-        i += 1;
-        for (0..prev_nl_n) |_| {
-            buf[i..][0..up_one_line.len].* = up_one_line.*;
-            i += up_one_line.len;
-        }
-    }
-
-    buf[i..][0..clear.len].* = clear.*;
-    i += clear.len;
+    i = computeClear(buf, i);
 
     buf[i..][0..finish_sync.len].* = finish_sync.*;
     i += finish_sync.len;
@@ -387,6 +375,26 @@ fn clearTerminal() void {
     write(buf[0..i]);
 }
 
+fn computeClear(buf: []u8, start_i: usize) usize {
+    var i = start_i;
+
+    const prev_nl_n = global_progress.newline_count;
+    if (prev_nl_n > 0) {
+        global_progress.newline_count = 0;
+        buf[i] = '\r';
+        i += 1;
+        for (1..prev_nl_n) |_| {
+            buf[i..][0..up_one_line.len].* = up_one_line.*;
+            i += up_one_line.len;
+        }
+    }
+
+    buf[i..][0..clear.len].* = clear.*;
+    i += clear.len;
+
+    return i;
+}
+
 const Children = struct {
     child: Node.OptionalIndex,
     sibling: Node.OptionalIndex,
@@ -467,25 +475,13 @@ fn computeRedraw() []u8 {
     buf[i..][0..start_sync.len].* = start_sync.*;
     i += start_sync.len;
 
-    const prev_nl_n = global_progress.newline_count;
-    if (prev_nl_n > 0) {
-        global_progress.newline_count = 0;
-        buf[i] = '\r';
-        i += 1;
-        for (0..prev_nl_n) |_| {
-            buf[i..][0..up_one_line.len].* = up_one_line.*;
-            i += up_one_line.len;
-        }
-    }
-
-    buf[i..][0..clear.len].* = clear.*;
-    i += clear.len;
+    i = computeClear(buf, i);
 
     const root_node_index: Node.Index = @enumFromInt(0);
     i = computeNode(buf, i, serialized_node_storage, serialized_node_parents, children, root_node_index);
 
     // Truncate trailing newline.
-    //if (buf[i - 1] == '\n') i -= 1;
+    if (buf[i - 1] == '\n') i -= 1;
 
     buf[i..][0..finish_sync.len].* = finish_sync.*;
     i += finish_sync.len;
-- 
2.54.0