From 96546af4758bfb120f04a7e6e81abc5cdc09589d Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Wed, 11 Oct 2023 17:23:27 -0700
Subject: [PATCH] terminal: test REP

---
 src/terminal/Terminal.zig   | 51 ++++++++++++++++++++++++++++++++---
 website/app/vt/rep/page.mdx | 53 +++++++++++++++++++++++++++++++++++++
 2 files changed, 100 insertions(+), 4 deletions(-)
 create mode 100644 website/app/vt/rep/page.mdx

diff --git a/src/terminal/Terminal.zig b/src/terminal/Terminal.zig
index 75ca871a3..67dfcc310 100644
--- a/src/terminal/Terminal.zig
+++ b/src/terminal/Terminal.zig
@@ -856,11 +856,10 @@ fn clearWideSpacerHead(self: *Terminal) void {
 }
 
 /// Print the previous printed character a repeated amount of times.
-pub fn printRepeat(self: *Terminal, count: usize) !void {
-    // TODO: test
+pub fn printRepeat(self: *Terminal, count_req: usize) !void {
     if (self.previous_char) |c| {
-        var i: usize = 0;
-        while (i < count) : (i += 1) try self.print(c);
+        const count = @max(count_req, 1);
+        for (0..count) |_| try self.print(c);
     }
 }
 
@@ -6082,3 +6081,47 @@ test "Terminal: tabClear all" {
     try t.horizontalTab();
     try testing.expectEqual(@as(usize, 29), t.screen.cursor.x);
 }
+
+test "Terminal: printRepeat simple" {
+    const alloc = testing.allocator;
+    var t = try init(alloc, 5, 5);
+    defer t.deinit(alloc);
+
+    try t.printString("A");
+    try t.printRepeat(1);
+
+    {
+        var str = try t.plainString(testing.allocator);
+        defer testing.allocator.free(str);
+        try testing.expectEqualStrings("AA", str);
+    }
+}
+
+test "Terminal: printRepeat wrap" {
+    const alloc = testing.allocator;
+    var t = try init(alloc, 5, 5);
+    defer t.deinit(alloc);
+
+    try t.printString("    A");
+    try t.printRepeat(1);
+
+    {
+        var str = try t.plainString(testing.allocator);
+        defer testing.allocator.free(str);
+        try testing.expectEqualStrings("    A\nA", str);
+    }
+}
+
+test "Terminal: printRepeat no previous character" {
+    const alloc = testing.allocator;
+    var t = try init(alloc, 5, 5);
+    defer t.deinit(alloc);
+
+    try t.printRepeat(1);
+
+    {
+        var str = try t.plainString(testing.allocator);
+        defer testing.allocator.free(str);
+        try testing.expectEqualStrings("", str);
+    }
+}
diff --git a/website/app/vt/rep/page.mdx b/website/app/vt/rep/page.mdx
new file mode 100644
index 000000000..91eba03cd
--- /dev/null
+++ b/website/app/vt/rep/page.mdx
@@ -0,0 +1,53 @@
+import VTSequence from "@/components/VTSequence";
+
+# Repeat Previous Character (REP)
+
+<VTSequence sequence={["CSI", "Pn", "b"]} />
+
+Repeat the previously printed character `n` times.
+
+The parameter `n` must be an integer greater than or equal to 1. If `n` is less than
+or equal to 0, adjust `n` to be 1. If `n` is omitted, `n` defaults to 1.
+
+In xterm, only characters with single byte (less than decimal 256) are
+supported. In most other mainstream terminals, any character is supported.
+
+Each repeated character behaves identically to if it was manually typed in.
+Therefore, soft-wrapping, margins, etc. all behave the same as if the
+character was typed.
+
+The previously printed character is any character that is printed through
+any means. The previously printed character is not limited to characters
+a user manually types. If there is no previously typed character, this sequence
+does nothing.
+
+## Validation
+
+### REP V-1: Simple Usage
+
+```bash
+printf "\033[1;1H" # move to top-left
+printf "\033[0J" # clear screen
+printf "A"
+printf "\033[b"
+```
+
+```
+|AAc_______|
+```
+
+### REP V-2: Soft-Wrap
+
+```bash
+cols=$(tput cols)
+printf "\033[1;1H" # move to top-left
+printf "\033[0J" # clear screen
+printf "\033[${cols}G"
+printf "A"
+printf "\033[b"
+```
+
+```
+|_________A|
+|Ac________|
+```