From c20b532c7a4f54923438e0dcabd4fd3db082460d Mon Sep 17 00:00:00 2001
From: Carter Li <zhangsongcui@live.cn>
Date: Tue, 2 Jun 2026 16:03:04 +0800
Subject: [PATCH] Common (Format): adds `|` for center aligning

---
 src/common/impl/format.c | 11 ++++++++---
 tests/format.c           | 14 ++++++++++++++
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/src/common/impl/format.c b/src/common/impl/format.c
index ae3e89c60..b230db7bb 100644
--- a/src/common/impl/format.c
+++ b/src/common/impl/format.c
@@ -614,7 +614,7 @@ static bool parseFormatString(FFstrbuf* buffer, const FFstrbuf* formatstr, uint3
 
         char* pSep = placeholderValue.chars;
         char cSep = '\0';
-        while (*pSep && *pSep != ':' && *pSep != '<' && *pSep != '>' && *pSep != '~') {
+        while (*pSep && *pSep != ':' && *pSep != '<' && *pSep != '>' && *pSep != '|' && *pSep != '~') {
             ++pSep;
         }
         if (*pSep) {
@@ -717,12 +717,17 @@ static bool parseFormatString(FFstrbuf* buffer, const FFstrbuf* formatstr, uint3
             } else if (cSep == ':') {
                 ffStrbufAppend(buffer, &tempString);
             } else {
-                if (cSep == '<') {
+                if (cSep == '<') { // left align
                     ffStrbufAppend(buffer, &tempString);
                     ffStrbufAppendNC(buffer, (uint32_t) truncLength - tempString.length, ' ');
-                } else {
+                } else if (cSep == '>') { // right align
                     ffStrbufAppendNC(buffer, (uint32_t) truncLength - tempString.length, ' ');
                     ffStrbufAppend(buffer, &tempString);
+                } else if (cSep == '|') { // center align
+                    uint32_t padding = ((uint32_t) truncLength - tempString.length) / 2;
+                    ffStrbufAppendNC(buffer, padding, ' ');
+                    ffStrbufAppend(buffer, &tempString);
+                    ffStrbufAppendNC(buffer, (uint32_t) truncLength - tempString.length - padding, ' ');
                 }
             }
 
diff --git a/tests/format.c b/tests/format.c
index 390b8e91a..2366f5588 100644
--- a/tests/format.c
+++ b/tests/format.c
@@ -62,6 +62,18 @@ int main(void) {
         VERIFY("output({>})", "12345 67890", "output()");
     }
 
+    {
+        VERIFY("output({1|20})", "12345 67890", "output(    12345 67890     )");
+        VERIFY("output({1|-20})", "12345 67890", "output(    12345 67890     )");
+        VERIFY("output({1|11})", "12345 67890", "output(12345 67890)");
+        VERIFY("output({1|-11})", "12345 67890", "output(12345 67890)");
+        VERIFY("output({1|6})", "12345 67890", "output(12345 )");
+        VERIFY("output({|6})", "12345 67890", "output(12345 )");
+        VERIFY("output({|-6})", "12345 67890", "output(12345…)");
+        VERIFY("output({|0})", "12345 67890", "output()");
+        VERIFY("output({|})", "12345 67890", "output()");
+    }
+
     {
         VERIFY("output({1n>20})", "12345 67890", "output({1n>20})");
         VERIFY("output({120})", "12345 67890", "output({120})");
@@ -123,6 +135,8 @@ int main(void) {
         VERIFY("output({1<8})", "\e[1m12345\e[m", "output(\e[1m12345   \e[m)");
         VERIFY("output({1>8})", "\e[1m12345\e[m", "output(\e[1m   12345\e[m)");
         VERIFY("output({1<1})", "\e[30;47m12345\e[m", "output(\e[30;47m1\e[m)");
+        VERIFY("output({1|8})", "\e[1m12345\e[m", "output(\e[1m 12345  \e[m)");
+        VERIFY("output({1|1})", "\e[30;47m12345\e[m", "output(\e[30;47m1\e[m)");
     }
 
     {