From 45dabbfe2b50d9afb0b9b64aa1bc04652b03dc17 Mon Sep 17 00:00:00 2001
From: Mark Olesen <Mark.Olesen@esi-group.com>
Date: Fri, 7 Jul 2017 12:33:41 +0200
Subject: [PATCH] ENH: provide Enum failsafe lookup

- if the enum name is not found, then warn and return the default.
---
 src/OpenFOAM/primitives/enums/Enum.C | 31 ++++++++++++++++++++++++++--
 src/OpenFOAM/primitives/enums/Enum.H | 12 +++++++++++
 2 files changed, 41 insertions(+), 2 deletions(-)

diff --git a/src/OpenFOAM/primitives/enums/Enum.C b/src/OpenFOAM/primitives/enums/Enum.C
index 8b4f2100f0..76f1323b8a 100644
--- a/src/OpenFOAM/primitives/enums/Enum.C
+++ b/src/OpenFOAM/primitives/enums/Enum.C
@@ -215,10 +215,37 @@ EnumType Foam::Enum<EnumType>::lookupOrDefault
     {
         return lookup(key, dict);
     }
-    else
+
+    return deflt;
+}
+
+
+template<class EnumType>
+EnumType Foam::Enum<EnumType>::lookupOrFailsafe
+(
+    const word& key,
+    const dictionary& dict,
+    const EnumType deflt
+) const
+{
+    if (dict.found(key))
     {
-        return deflt;
+        const word enumName(dict.lookup(key));
+        const label idx = getIndex(enumName);
+
+        if (idx < 0)
+        {
+            IOWarningInFunction(dict)
+                << "bad " << key <<" specifier " << enumName
+                << " using " << getName(deflt) << endl;
+        }
+        else
+        {
+            return EnumType(values_[idx]);
+        }
     }
+
+    return deflt;
 }
 
 
diff --git a/src/OpenFOAM/primitives/enums/Enum.H b/src/OpenFOAM/primitives/enums/Enum.H
index dde620fb26..b57fc9891a 100644
--- a/src/OpenFOAM/primitives/enums/Enum.H
+++ b/src/OpenFOAM/primitives/enums/Enum.H
@@ -161,6 +161,18 @@ public:
         ) const;
 
 
+        //- Find the key in the dictionary and return the corresponding
+        //  enumeration element based on its name.
+        //  Return the default value if the key was not found in the dictionary
+        //  or if the enumerated name was incorrect (emit warning)
+        EnumType lookupOrFailsafe
+        (
+            const word& key,
+            const dictionary& dict,
+            const EnumType deflt
+        ) const;
+
+
       // IO
 
         //- Read a word from Istream and return the corresponding enumeration