From ed1deacce8c035b65f6d99e815ca46be90962880 Mon Sep 17 00:00:00 2001
From: Henning Stahlke <github@henningstahlke.de>
Date: Fri, 5 Jun 2020 18:16:48 +0200
Subject: [PATCH] props.nas: add isValidPropName and makeValidPropName; add
 props.nut

---
 Nasal/props.nas | 32 +++++++++++++++++++++++++++++++-
 Nasal/props.nut | 43 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 74 insertions(+), 1 deletion(-)
 create mode 100644 Nasal/props.nut

diff --git a/Nasal/props.nas b/Nasal/props.nas
index 652976de8..cfe1b1bda 100644
--- a/Nasal/props.nas
+++ b/Nasal/props.nas
@@ -112,7 +112,37 @@ var Node = {
                 me.getPath()~" "~me.getType());
             return 0;
         }
-    }
+    },
+    
+    # checks if a string can be used as a prop name
+    # returns 0 (invalid) or 1 (valid)
+    # as string operations are expensive, use this only when necessary, 
+    # especially do not use in update loops
+    isValidPropName: func(s) {
+        if (!size(s)) return 0;
+        var _ispropspecial =  func(c) { c == `_` or c == `.` or c == `-`; }
+        var _ispropname =  func(c) string.isalnum(c) or _ispropspecial(c);
+        if (!string.isalpha(s[0]) and s[0] != `_`) return 0;
+        for (var i=1; i < size(s); i += 1) {
+            if (!_ispropname(s[i])) return 0;
+        }
+        return 1;
+    },
+
+    # replaces any invalid char by "_"
+    # as string operations are expensive, use this only when necessary, 
+    # especially do not use in update loops
+    makeValidPropName: func(s) {
+        if (!size(s)) return nil;
+        var _ispropspecial =  func(c) { c == `_` or c == `.` or c == `-`; }
+        var _ispropname =  func(c) string.isalnum(c) or _ispropspecial(c);
+        var rv = "";
+        rv ~= (!string.isalpha(s[0])) ?  "_" : chr(s[0]);
+        for (var i=1; i < size(s); i += 1) {
+            rv ~= (_ispropname(s[i])) ? chr(s[i]) : "_";
+        }
+        return rv;
+    },    
 };
 
 ##
diff --git a/Nasal/props.nut b/Nasal/props.nut
new file mode 100644
index 000000000..e644a51e9
--- /dev/null
+++ b/Nasal/props.nut
@@ -0,0 +1,43 @@
+#-------------------------------------------------------------------------------
+# SPDX-License-Identifier: GPL-2.0-or-later
+#-------------------------------------------------------------------------------
+# props.Node.nut - Nasal Unit Test for props.Node.nas
+# created: 06/2020
+# Copyright (C) 2020 by Henning Stahlke
+#-------------------------------------------------------------------------------
+
+var setUp = func {
+    print("setUp "~caller(0)[2]~" ");
+};
+
+var tearDown = func {
+
+};
+
+var test_isValidPropName = func() {
+    # test valid names
+    unitTest.assert(props.Node.isValidPropName("abc123") == 1, "isValidPropName()");
+    unitTest.assert(props.Node.isValidPropName("_abc123") == 1, "isValidPropName()");
+    unitTest.assert(props.Node.isValidPropName("_1a") == 1, "isValidPropName()");
+    unitTest.assert(props.Node.isValidPropName("_1a.-") == 1, "isValidPropName()");
+    # test invalid names
+    unitTest.assert(props.Node.isValidPropName("1a") == 0, "isValidPropName()");
+    unitTest.assert(props.Node.isValidPropName("abä") == 0, "isValidPropName()");
+    unitTest.assert(props.Node.isValidPropName("foo:bar") == 0, "isValidPropName()");
+    unitTest.assert(props.Node.isValidPropName("foo<bar") == 0, "isValidPropName()");
+    unitTest.assert(props.Node.isValidPropName("") == 0, "isValidPropName()");
+}
+
+var test_makeValidPropName = func() {
+    # test valid names
+    unitTest.assert(props.Node.makeValidPropName("abc123") == "abc123", "makeValidPropName()");
+    unitTest.assert(props.Node.makeValidPropName("_abc123") == "_abc123", "makeValidPropName()");
+    unitTest.assert(props.Node.makeValidPropName("_1a") == "_1a", "makeValidPropName()");
+    unitTest.assert(props.Node.makeValidPropName("_1a.-") == "_1a.-", "makeValidPropName()");
+    # test invalid names
+    unitTest.assert(props.Node.makeValidPropName("1a") == "_a", "makeValidPropName()");
+    unitTest.assert(props.Node.makeValidPropName("foo:bar") == "foo_bar", "makeValidPropName()");
+    unitTest.assert(props.Node.makeValidPropName("foo<bar") == "foo_bar", "makeValidPropName()");
+    unitTest.assert(props.Node.makeValidPropName("") == nil, "makeValidPropName()");
+    unitTest.assert(props.Node.makeValidPropName("abä") == "ab_", "makeValidPropName()");
+}