From 96a9faf2fd03c93acdb9db813785d7e5b74da4cd Mon Sep 17 00:00:00 2001
From: Larpon <Larpon@users.noreply.github.com>
Date: Tue, 7 Jun 2022 17:43:06 +0200
Subject: [PATCH] strings: add split_capital (#14716)

---
 vlib/strings/strings.v      | 21 +++++++++++++++++++++
 vlib/strings/strings_test.v | 11 +++++++++++
 2 files changed, 32 insertions(+)

diff --git a/vlib/strings/strings.v b/vlib/strings/strings.v
index ce0c82ebc..df08a26db 100644
--- a/vlib/strings/strings.v
+++ b/vlib/strings/strings.v
@@ -126,3 +126,24 @@ pub fn find_between_pair_string(input string, start string, end string) string {
 	}
 	return ''
 }
+
+// split_capital returns an array containing the contents of `s` split by capital letters.
+// Example: assert strings.split_capital('XYZ') == ['X', 'Y', 'Z']
+// Example: assert strings.split_capital('XYStar') == ['X', 'Y', 'Star']
+pub fn split_capital(s string) []string {
+	mut res := []string{}
+	mut word_start := 0
+	for idx, c in s {
+		if c >= `A` && c <= `Z` {
+			if word_start != idx {
+				res << s#[word_start..idx]
+			}
+			word_start = idx
+			continue
+		}
+	}
+	if word_start != s.len {
+		res << s#[word_start..]
+	}
+	return res
+}
diff --git a/vlib/strings/strings_test.v b/vlib/strings/strings_test.v
index 0475b6aad..579d99b28 100644
--- a/vlib/strings/strings_test.v
+++ b/vlib/strings/strings_test.v
@@ -94,3 +94,14 @@ fn test_find_between_pair_family() {
 		assert '$e1' == '$e2'
 	}
 }
+
+fn test_split_capital() {
+	assert strings.split_capital('') == []
+	assert strings.split_capital('abc') == ['abc']
+	assert strings.split_capital('X') == ['X']
+	assert strings.split_capital('XX') == ['X', 'X']
+	assert strings.split_capital('XYZ') == ['X', 'Y', 'Z']
+	assert strings.split_capital('JohnWilliams') == ['John', 'Williams']
+	assert strings.split_capital('JDStar') == ['J', 'D', 'Star']
+	assert strings.split_capital('cpDumpRotarySpring') == ['cp', 'Dump', 'Rotary', 'Spring']
+}
-- 
2.30.2