ENH: ensure self-assignment and self-swapping are a no-op for string types

- simplifies their use when reordering lists etc.
  (word, fileName, keyType, wordRe)

- "unfriend" IO operators for string types. They require no internal access

- add compile/uncompile methods to keyType for symmetry with wordRe

- when outputting keyType/wordRe, be more explicit about them using
  writeQuoted()

src/OSspecific/POSIX/regExp.H

@@ -84,7 +84,7 @@ public:
         //  - range: '[', ']' \n
         //
         // \note The presence of '{', '}' regex bounds is not considered
-        inline static bool meta(const char c);
+        inline static bool meta(char c);
 
 
     // Constructors

src/OSspecific/POSIX/regExpI.H

@@ -28,7 +28,7 @@ License
 
 // * * * * * * * * * * * * * Static Member Functions * * * * * * * * * * * * //
 
-inline bool Foam::regExp::meta(const char c)
+inline bool Foam::regExp::meta(char c)
 {
     return
     (

src/OpenFOAM/db/IOstreams/IOstreams/Ostream.C

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2016 OpenCFD Ltd.
+    \\  /    A nd           | Copyright (C) 2016-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2016 OpenFOAM Foundation
@@ -35,9 +35,10 @@ License
 
 void Foam::Ostream::decrIndent()
 {
-    if (indentLevel_ == 0)
+    if (!indentLevel_)
     {
-        cerr<< "Ostream::decrIndent() : attempt to decrement 0 indent level"
+        std::cerr
+            << "Ostream::decrIndent() : attempt to decrement 0 indent level"
             << std::endl;
     }
     else
@@ -56,17 +57,17 @@ Foam::Ostream& Foam::Ostream::write(const keyType& kw)
 Foam::Ostream& Foam::Ostream::writeKeyword(const keyType& kw)
 {
     indent();
-    write(kw);
+    writeQuoted(kw, kw.isPattern());
 
     label nSpaces = entryIndentation_ - label(kw.size());
 
-    // pattern is surrounded by quotes
+    // Account for quotes surrounding pattern
     if (kw.isPattern())
     {
         nSpaces -= 2;
     }
 
-    // could also increment by indentSize_ ...
+    // Could also increment by indentSize_ ...
     if (nSpaces < 1)
     {
         nSpaces = 1;
@@ -81,9 +82,9 @@ Foam::Ostream& Foam::Ostream::writeKeyword(const keyType& kw)
 }
 
 
-Foam::Ostream& Foam::Ostream::beginBlock(const keyType& keyword)
+Foam::Ostream& Foam::Ostream::beginBlock(const keyType& kw)
 {
-    indent(); write(keyword); write('\n');
+    indent(); writeQuoted(kw, kw.isPattern()); write('\n');
     beginBlock();
 
     return *this;

src/OpenFOAM/db/IOstreams/IOstreams/Ostream.H

@@ -185,7 +185,7 @@ public:
 
             //- Write begin block group with the given name
             //  Increments indentation, adds newline.
-            virtual Ostream& beginBlock(const keyType& keyword);
+            virtual Ostream& beginBlock(const keyType& kw);
 
             //- Write begin block group without a name
             //  Increments indentation, adds newline.

src/OpenFOAM/primitives/hashes/SHA1/SHA1.H

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           |
+    \\  /    A nd           | Copyright (C) 2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2016 OpenFOAM Foundation
@@ -55,15 +55,6 @@ SourceFiles
 namespace Foam
 {
 
-// Forward declaration of classes
-class Ostream;
-
-// Forward declaration of friend functions and operators
-class SHA1;
-class SHA1Digest;
-Ostream& operator<<(Ostream&, const SHA1&);
-
-
 /*---------------------------------------------------------------------------*\
                             Class SHA1 Declaration
 \*---------------------------------------------------------------------------*/
@@ -91,6 +82,7 @@ class SHA1
         //- The input processing buffer
         uint32_t buffer_[32];
 
+
     // Private Member Functions
 
         //- Process data block-wise, LEN must be a multiple of 64!
@@ -172,14 +164,13 @@ public:
         //- Convert to a SHA1Digest,
         //  calculate current %digest from appended data
         inline operator SHA1Digest() const;
+};
 
 
-    // Friend Operators
-
-        //- Output the %digest
-        inline friend Ostream& operator<<(Ostream&, const SHA1&);
+// IOstream Operators
 
-};
+//- Output the %digest
+inline Ostream& operator<<(Ostream& os, const SHA1& sha);
 
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

src/OpenFOAM/primitives/hashes/SHA1/SHA1I.H

@@ -136,7 +136,7 @@ inline Foam::SHA1::operator Foam::SHA1Digest() const
 
 inline Foam::Ostream& Foam::operator<<(Ostream& os, const SHA1& sha)
 {
-    return os  << sha.digest();
+    return (os << sha.digest());
 }
 
 

src/OpenFOAM/primitives/strings/fileName/fileName.H

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2016-2018 OpenCFD Ltd.
+    \\  /    A nd           | Copyright (C) 2016-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2017 OpenFOAM Foundation
@@ -62,10 +62,6 @@ typedef List<word> wordList;
 class wordRe;
 class fileName;
 
-Istream& operator>>(Istream&, fileName&);
-Ostream& operator<<(Ostream&, const fileName&);
-
-
 /*---------------------------------------------------------------------------*\
                           Class fileName Declaration
 \*---------------------------------------------------------------------------*/
@@ -74,12 +70,6 @@ class fileName
 :
     public string
 {
-    // Private Member Functions
-
-        //- Strip invalid characters
-        inline void stripInvalid();
-
-
 public:
 
     //- Enumerations to handle directory entry types.
@@ -94,7 +84,10 @@ public:
 
     // Static data members
 
+        //- The typeName
         static const char* const typeName;
+
+        //- Debugging
         static int debug;
 
         //- An empty fileName
@@ -161,6 +154,8 @@ public:
         //- that ignores duplicate or trailing slashes.
         static bool equals(const std::string& s1, const std::string& s2);
 
+        //- Strip invalid characters
+        inline void stripInvalid();
 
         //- Cleanup filename
         //
@@ -353,15 +348,17 @@ public:
         ) const;
 
 
-    // Member operators
+    // Member Operators
 
     // Assignment
 
         //- Copy assignment, no character validation required
-        fileName& operator=(const fileName&) = default;
+        //  Self-assignment is a no-op.
+        inline fileName& operator=(const fileName& str);
 
         //- Move assignment, no character validation required
-        fileName& operator=(fileName&&) = default;
+        //  Self-assignment is a no-op.
+        inline fileName& operator=(fileName&& str);
 
         //- Copy assignment, no character validation required
         inline fileName& operator=(const word& str);
@@ -390,13 +387,16 @@ public:
         //- Append a path element with '/' separator.
         //  No '/' separator is added if this or the argument are empty.
         fileName& operator/=(const string& other);
+};
 
 
-    // IOstream operators
+// IOstream Operators
 
-        friend Istream& operator>>(Istream& is, fileName& fn);
-        friend Ostream& operator<<(Ostream& os, const fileName& fn);
-};
+//- Read operator
+Istream& operator>>(Istream& is, fileName& val);
+
+//- Write operator
+Ostream& operator<<(Ostream& os, const fileName& val);
 
 
 // Global Operators

src/OpenFOAM/primitives/strings/fileName/fileNameI.H

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2016-2018 OpenCFD Ltd.
+    \\  /    A nd           | Copyright (C) 2016-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011 OpenFOAM Foundation
@@ -25,32 +25,7 @@ License
 
 \*---------------------------------------------------------------------------*/
 
-#include <iostream>  // for std::cerr
-
-// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
-
-inline void Foam::fileName::stripInvalid()
-{
-    // Skip stripping unless debug is active (to avoid costly operations)
-    if (debug && string::stripInvalid<fileName>(*this))
-    {
-        std::cerr
-            << "fileName::stripInvalid() called for invalid fileName "
-            << this->c_str() << std::endl;
-
-        if (debug > 1)
-        {
-            std::cerr
-                << "    For debug level (= " << debug
-                << ") > 1 this is considered fatal" << std::endl;
-            std::abort();
-        }
-
-        removeRepeated('/');
-        removeTrailing('/');
-    }
-}
-
+#include <iostream>  // For std::cerr
 
 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
@@ -134,6 +109,29 @@ inline bool Foam::fileName::valid(char c)
 }
 
 
+inline void Foam::fileName::stripInvalid()
+{
+    // Only strip when debug is active (potentially costly operation)
+    if (debug && string::stripInvalid<fileName>(*this))
+    {
+        std::cerr
+            << "fileName::stripInvalid() called for invalid fileName "
+            << this->c_str() << std::endl;
+
+        if (debug > 1)
+        {
+            std::cerr
+                << "    For debug level (= " << debug
+                << ") > 1 this is considered fatal" << std::endl;
+            std::abort();
+        }
+
+        removeRepeated('/');
+        removeTrailing('/');
+    }
+}
+
+
 inline bool Foam::fileName::isAbsolute(const std::string& str)
 {
     return !str.empty() && str[0] == '/';
@@ -258,6 +256,28 @@ inline Foam::fileName& Foam::fileName::ext(const word& ending)
 
 // * * * * * * * * * * * * * * * Member Operators  * * * * * * * * * * * * * //
 
+inline Foam::fileName& Foam::fileName::operator=(const fileName& str)
+{
+    // Self-assignment is a no-op
+    if (this != &str)
+    {
+        assign(str);
+    }
+    return *this;
+}
+
+
+inline Foam::fileName& Foam::fileName::operator=(fileName&& str)
+{
+    // Self-assignment is a no-op
+    if (this != &str)
+    {
+        assign(std::move(str));
+    }
+    return *this;
+}
+
+
 inline Foam::fileName& Foam::fileName::operator=(const word& str)
 {
     assign(str);

src/OpenFOAM/primitives/strings/fileName/fileNameIO.C

@@ -72,9 +72,9 @@ Foam::Istream& Foam::operator>>(Istream& is, fileName& val)
 }
 
 
-Foam::Ostream& Foam::operator<<(Ostream& os, const fileName& fn)
+Foam::Ostream& Foam::operator<<(Ostream& os, const fileName& val)
 {
-    os.write(fn);
+    os.write(val);
     os.check(FUNCTION_NAME);
     return os;
 }

src/OpenFOAM/primitives/strings/keyType/keyType.C

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2018 OpenCFD Ltd.
+    \\  /    A nd           | Copyright (C) 2018-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2015 OpenFOAM Foundation
@@ -76,12 +76,13 @@ Foam::Istream& Foam::operator>>(Istream& is, keyType& val)
     if (t.isWord())
     {
         val = t.wordToken();
+        val.uncompile();  // Non-regex
     }
     else if (t.isString())
     {
         // Assign from string, treat as regular expression
         val = t.stringToken();
-        val.isPattern_ = true;
+        val.compile();   // As regex
 
         // Flag empty strings as an error
         if (val.empty())
@@ -108,9 +109,9 @@ Foam::Istream& Foam::operator>>(Istream& is, keyType& val)
 }
 
 
-Foam::Ostream& Foam::operator<<(Ostream& os, const keyType& kw)
+Foam::Ostream& Foam::operator<<(Ostream& os, const keyType& val)
 {
-    os.write(kw);
+    os.writeQuoted(val, val.isPattern());
     os.check(FUNCTION_NAME);
     return os;
 }

src/OpenFOAM/primitives/strings/keyType/keyType.H

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2017-2018 OpenCFD Ltd.
+    \\  /    A nd           | Copyright (C) 2017-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2016 OpenFOAM Foundation
@@ -48,13 +48,9 @@ SourceFiles
 namespace Foam
 {
 
-// Forward declarations
-class keyType;
+// Forward Declarations
 class Istream;
 class Ostream;
-Istream& operator>>(Istream& is, keyType& kw);
-Ostream& operator<<(Ostream& os, const keyType& kw);
-
 
 /*---------------------------------------------------------------------------*\
                            Class keyType Declaration
@@ -64,9 +60,9 @@ class keyType
 :
     public word
 {
-    // Private data
+    // Private Data
 
-        //- Is the keyType a pattern (regular expression)
+        //- Treat keyType as a pattern (regular expression)
         bool isPattern_;
 
 
@@ -78,13 +74,13 @@ class keyType
 
 public:
 
-    // Static data members
+    // Static Data Members
 
         //- An empty keyType
         static const keyType null;
 
 
-    // Public data types
+    // Public Data Types
 
         //- Enumeration for search/match modes as bitmask
         //  eg, (keyType::REGEX | keyType::RECURSIVE)
@@ -142,18 +138,40 @@ public:
         //  permit brace-brackets, which are valid for some regexs.
         inline static bool valid(char c);
 
+
+    // Access
+
         //- The keyType is treated as literal, not as pattern.
         inline bool isLiteral() const;
 
         //- The keyType is treated as a pattern, not as literal string.
         inline bool isPattern() const;
 
-        //- Swap contents
+
+    // Infrastructure
+
+        //- Mark as regular expression
+        inline bool compile();
+
+        //- Mark as literal, instead of a regular expression.
+        //  Optionally strip invalid word characters.
+        inline void uncompile(bool doStrip = false);
+
+
+    // Editing
+
+        //- Clear string and set as literal
+        inline void clear();
+
+        //- Swap contents. Self-swapping is a no-op.
         inline void swap(keyType& s);
 
+
+    // Matching/Searching
+
         //- Smart match as regular expression or as a string.
         //  Optionally force a literal match only
-        bool match(const std::string& text, bool literal = false) const;
+        bool match(const std::string& text, bool literal=false) const;
 
 
     // Member Operators
@@ -164,9 +182,11 @@ public:
 
 
         //- Copy assignment, retaining type (literal or regex)
+        //  Self-assignment is a no-op.
         inline void operator=(const keyType& s);
 
         //- Move assignment, retaining type (literal or regex)
+        //  Self-assignment is a no-op.
         inline void operator=(keyType&& s);
 
         //- Assign as word, treat as literal
@@ -177,13 +197,16 @@ public:
 
         //- Assign as word, treat as literal
         inline void operator=(const char* s);
+};
 
 
-    // IOstream Operators
+// IOstream Operators
 
-        friend Istream& operator>>(Istream& is, keyType& kw);
-        friend Ostream& operator<<(Ostream& os, const keyType& kw);
-};
+//- Read operator
+Istream& operator>>(Istream& is, keyType& val);
+
+//- Write operator
+Ostream& operator<<(Ostream& os, const keyType& val);
 
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

src/OpenFOAM/primitives/strings/keyType/keyTypeI.H

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2017 OpenCFD Ltd.
+    \\  /    A nd           | Copyright (C) 2017-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2016 OpenFOAM Foundation
@@ -130,8 +130,40 @@ inline bool Foam::keyType::isPattern() const
 }
 
 
+inline bool Foam::keyType::compile()
+{
+    isPattern_ = true;
+    return true;
+}
+
+
+inline void Foam::keyType::uncompile(bool doStrip)
+{
+    // Only strip when debug is active (potentially costly operation)
+    if (isPattern_ && doStrip && word::debug)
+    {
+        string::stripInvalid<word>(*this);
+    }
+
+    isPattern_ = false;
+}
+
+
+inline void Foam::keyType::clear()
+{
+    word::clear();
+    isPattern_ = false;
+}
+
+
 inline void Foam::keyType::swap(keyType& s)
 {
+    // Self-swapping is a no-op
+    if (this == &s)
+    {
+        return;
+    }
+
     word::swap(static_cast<word&>(s));
     std::swap(isPattern_, s.isPattern_);
 }
@@ -147,6 +179,12 @@ inline bool Foam::keyType::operator()(const std::string& text) const
 
 inline void Foam::keyType::operator=(const keyType& s)
 {
+    // Self-assignment is a no-op
+    if (this == &s)
+    {
+        return;
+    }
+
     assign(s); // Bypasses char checking
     isPattern_ = s.isPattern_;
 }
@@ -154,6 +192,12 @@ inline void Foam::keyType::operator=(const keyType& s)
 
 inline void Foam::keyType::operator=(keyType&& s)
 {
+    // Self-assignment is a no-op
+    if (this == &s)
+    {
+        return;
+    }
+
     clear();
     swap(s);
 }

src/OpenFOAM/primitives/strings/lists/CStringList.H

@@ -58,20 +58,16 @@ Description
 namespace Foam
 {
 
-// Forward declarations
-class Ostream;
-class CStringList;
+// Forward Declarations
 template<class String> class SubStrings;
 
-Ostream& operator<<(Ostream& os, const CStringList& list);
-
 /*---------------------------------------------------------------------------*\
                          Class CStringList Declaration
 \*---------------------------------------------------------------------------*/
 
 class CStringList
 {
-    // Private data
+    // Private Data
 
         //- Number of strings
         int argc_;
@@ -127,7 +123,7 @@ public:
         inline explicit CStringList(const SubStrings<StringType>& input);
 
 
-    //- Destructor
+    //- Destructor. Invokes clear() to free memory.
     inline ~CStringList();
 
 
@@ -196,13 +192,13 @@ public: