3 files changed, 57 insertions, 1 deletions
diff --git a/src/CHANGES.txt b/src/CHANGES.txt
index 015622e..0a30bfa 100755
--- a/src/CHANGES.txt
+++ b/src/CHANGES.txt
@@ -15,6 +15,7 @@ RELEASE  VERSION/DATE TO BE FILLED IN LATER
   From Mats Wichmann
     - Replace instances of string find method with "in" checks where
       the index from find() was not used.
+    - CmdStringHolder fix from issue #3428
     - Turn previously deprecated debug options into failures:
       --debug=tree, --debug=dtree, --debug=stree, --debug=nomemoizer.
 
diff --git a/src/engine/SCons/Subst.py b/src/engine/SCons/Subst.py
index 6f62198..2de64c5 100644
--- a/src/engine/SCons/Subst.py
+++ b/src/engine/SCons/Subst.py
@@ -409,7 +409,7 @@ def scons_subst(strSubst, env, mode=SUBST_RAW, target=None, source=None, gvars={
     handles separating command lines into lists of arguments, so see
     that function if that's what you're looking for.
     """
-    if isinstance(strSubst, str) and strSubst.find('$') < 0:
+    if (isinstance(strSubst, str) and '$' not in strSubst) or isinstance(strSubst, CmdStringHolder):
         return strSubst
 
     class StringSubber(object):
diff --git a/test/Subst/bug3428.py b/test/Subst/bug3428.py
new file mode 100644
index 0000000..00587e6
--- /dev/null
+++ b/test/Subst/bug3428.py
@@ -0,0 +1,55 @@
+#!/usr/bin/env python
+#
+# __COPYRIGHT__
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be included
+# in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
+# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+#
+
+__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
+
+"""
+Verify that CmdStringHolder doesn't trip in Subst on doing
+a string-only operation that does not work on UserString class.
+Issue: https://github.com/SCons/scons/issues/3428
+"""
+
+import TestSCons
+
+test = TestSCons.TestSCons(match = TestSCons.match_re_dotall)
+
+
+test.write('SConstruct', """\
+env = Environment()
+env.Append(LIBPATH=["path1/sub1","path1/sub2"])
+lst = env.Flatten(env.subst_list("$LIBPATH"))
+for i in lst:
+    env.Dir(i)
+""")
+
+test.run(status=0)
+
+
+test.pass_test()
+
+# Local Variables:
+# tab-width:4
+# indent-tabs-mode:nil
+# End:
+# vim: set expandtab tabstop=4 shiftwidth=4: