From 6f2376a649d8663e17c56c5d6ff929b3dfa05670 Mon Sep 17 00:00:00 2001
From: mattijs <mattijs>
Date: Tue, 30 Oct 2018 13:26:23 +0000
Subject: [PATCH] ENH: ConstantField: allow 'constant' keyword. See #1046.

---
 .../ConstantField/ConstantField.C             | 50 ++++++++++++++++++-
 .../ConstantField/ConstantField.H             | 12 ++++-
 2 files changed, 59 insertions(+), 3 deletions(-)

diff --git a/src/meshTools/PatchFunction1/ConstantField/ConstantField.C b/src/meshTools/PatchFunction1/ConstantField/ConstantField.C
index a6afaa09f4..dc7ad608aa 100644
--- a/src/meshTools/PatchFunction1/ConstantField/ConstantField.C
+++ b/src/meshTools/PatchFunction1/ConstantField/ConstantField.C
@@ -42,6 +42,54 @@ Foam::PatchFunction1Types::ConstantField<Type>::ConstantField
 {}
 
 
+template<class Type>
+Foam::Field<Type> Foam::PatchFunction1Types::ConstantField<Type>::getValue
+(
+    const word& keyword,
+    const dictionary& dict,
+    const label len
+)
+{
+    Field<Type> fld;
+
+    if (len)
+    {
+        ITstream& is = dict.lookup(keyword);
+
+        // Read first token
+        token firstToken(is);
+
+        if (firstToken.isWord())
+        {
+            if
+            (
+                firstToken.wordToken() == "uniform"
+             || firstToken.wordToken() == "constant"
+            )
+            {
+                fld.setSize(len);
+                fld = pTraits<Type>(is);
+            }
+            else
+            {
+                FatalIOErrorInFunction(dict)
+                    << "expected keyword 'uniform' or 'constant', found "
+                    << firstToken.wordToken()
+                    << exit(FatalIOError);
+            }
+        }
+        else
+        {
+            fld.setSize(len);
+
+            is.putBack(firstToken);
+            fld = pTraits<Type>(is);
+        }
+    }
+    return fld;
+}
+
+
 template<class Type>
 Foam::PatchFunction1Types::ConstantField<Type>::ConstantField
 (
@@ -52,7 +100,7 @@ Foam::PatchFunction1Types::ConstantField<Type>::ConstantField
 )
 :
     PatchFunction1<Type>(pp, entryName, dict, faceValues),
-    value_(entryName, dict, pp.size())
+    value_(getValue(entryName, dict, pp.size()))
 {}
 
 
diff --git a/src/meshTools/PatchFunction1/ConstantField/ConstantField.H b/src/meshTools/PatchFunction1/ConstantField/ConstantField.H
index 703cfc49c1..c9eeea67f8 100644
--- a/src/meshTools/PatchFunction1/ConstantField/ConstantField.H
+++ b/src/meshTools/PatchFunction1/ConstantField/ConstantField.H
@@ -2,8 +2,8 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2011-2017 OpenFOAM Foundation
-     \\/     M anipulation  | Copyright (C) 2015 OpenCFD Ltd.
+    \\  /    A nd           | Copyright (C) 2018 OpenCFD Ltd.
+     \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -66,6 +66,14 @@ class ConstantField
 
     // Private Member Functions
 
+        //- Helper to read value from dictionary
+        static Field<Type> getValue
+        (
+            const word& keyword,
+            const dictionary& dict,
+            const label len
+        );
+
         //- No copy assignment
         void operator=(const ConstantField<Type>&) = delete;