From 1ec7201558db4203d57d499d97b97d3df0f07c19 Mon Sep 17 00:00:00 2001
From: Matthew Woehlke <matthew.woehlke@kitware.com>
Date: Mon, 1 Dec 2025 12:31:24 -0500
Subject: [PATCH] cmStringAlgorithms: Add cmStripWhitespace

Add a utility function to strip whitespace from a `string_view`. This is
identical to the existing `cmTrimWhitespace`, but does not allocate a
new `string`, instead returning the result as another `string_view`.
---
 Source/cmStringAlgorithms.cxx | 18 ++++++++++++++++++
 Source/cmStringAlgorithms.h   |  6 ++++++
 2 files changed, 24 insertions(+)

diff --git a/Source/cmStringAlgorithms.cxx b/Source/cmStringAlgorithms.cxx
index df3b7d9c6d..544d7160c1 100644
--- a/Source/cmStringAlgorithms.cxx
+++ b/Source/cmStringAlgorithms.cxx
@@ -38,6 +38,24 @@ std::string cmTrimWhitespace(cm::string_view str)
   return std::string(start, stop + 1);
 }
 
+cm::string_view cmStripWhitespace(cm::string_view str)
+{
+  std::string::size_type const l = str.size();
+
+  std::string::size_type s = 0;
+  while (s < l && cmIsSpace(str[s])) {
+    ++s;
+  }
+  if (s == l) {
+    return cm::string_view{};
+  }
+  std::string::size_type e = l - 1;
+  while (cmIsSpace(str[e])) {
+    --e;
+  }
+  return str.substr(s, e + 1 - s);
+}
+
 std::string cmRemoveQuotes(cm::string_view str)
 {
   // We process only strings that have two quotes at least.
diff --git a/Source/cmStringAlgorithms.h b/Source/cmStringAlgorithms.h
index b0d01c00ba..d847ece5bd 100644
--- a/Source/cmStringAlgorithms.h
+++ b/Source/cmStringAlgorithms.h
@@ -62,6 +62,12 @@ inline bool cmIsSpace(char ch)
 /** Returns a string that has whitespace removed from the start and the end. */
 std::string cmTrimWhitespace(cm::string_view str);
 
+/**
+ * Returns a string view that has whitespace removed from the start and the
+ * end.
+ */
+cm::string_view cmStripWhitespace(cm::string_view str);
+
 /** Returns a string that has quotes removed from the start and the end. */
 std::string cmRemoveQuotes(cm::string_view str);