ENH: dictionary lookup with detection of zero tokens (#1033)

- the opposite problem from issue #762. Now we also test if the input
  token stream had any tokens at all.

- called by the dictionary get<> and readEntry() methods.

applications/test/dictionary2/Test-dictionary2.C

@@ -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) 2017-2018 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -25,8 +25,7 @@ Application
     Test-dictionary2
 
 Description
-
-    Test dictionary insertion
+    Test dictionary insertion and some reading functionality.
 
 \*---------------------------------------------------------------------------*/
 
@@ -208,6 +207,83 @@ int main(int argc, char *argv[])
     Info<< nl << "dictionary" << nl << nl;
     dict1.write(Info, false);
 
+
+    {
+        Info<< nl << "Test reading good/bad/empty scalar entries" << nl;
+        dictionary dict2
+        (
+            IStringStream
+            (
+                "good 3.14159;\n"
+                "empty;\n"
+                // "bad  text;\n"            // always fails
+                // "bad  3.14159 1234;\n"    // fails for readScalar
+            )()
+        );
+        dict2.write(Info);
+
+
+        // With readScalar
+        {
+            Info<< nl << "Test some bad input with readScalar()" << nl;
+
+            const bool throwingIOError = FatalIOError.throwExceptions();
+            const bool throwingError = FatalError.throwExceptions();
+
+            try
+            {
+                scalar val1 = readScalar(dict2.lookup("good"));
+                // scalar val2 = readScalar(dict2.lookup("bad"));
+                scalar val2 = -1;
+                scalar val3 = readScalar(dict2.lookup("empty"));
+
+                Info<< "got good=" << val1 << " bad=" << val2
+                    << " empty=" << val3 << nl;
+            }
+            catch (Foam::IOerror& err)
+            {
+                Info<< "Caught FatalIOError " << err << nl << endl;
+            }
+            catch (Foam::error& err)
+            {
+                Info<< "Caught FatalError " << err << nl << endl;
+            }
+            FatalError.throwExceptions(throwingError);
+            FatalIOError.throwExceptions(throwingIOError);
+        }
+
+
+        // With get<scalar>
+        {
+            Info<< nl << "Test some bad input with get<scalar>()" << nl;
+
+            const bool throwingIOError = FatalIOError.throwExceptions();
+            const bool throwingError = FatalError.throwExceptions();
+
+            try
+            {
+                scalar val1 = dict2.get<scalar>("good");
+                // scalar val2 = dict2.get<scalar>("bad");
+                scalar val2 = -1;
+                scalar val3 = dict2.get<scalar>("empty");
+
+                Info<< "got good=" << val1 << " bad=" << val2
+                    << " empty=" << val3 << nl;
+            }
+            catch (Foam::IOerror& err)
+            {
+                Info<< "Caught FatalIOError " << err << nl << endl;
+            }
+            catch (Foam::error& err)
+            {
+                Info<< "Caught FatalError " << err << nl << endl;
+            }
+            FatalError.throwExceptions(throwingError);
+            FatalIOError.throwExceptions(throwingIOError);
+        }
+    }
+
+
     Info<< "\nDone\n" << endl;
 
     return 0;

src/OpenFOAM/db/dictionary/dictionary.C

@@ -48,24 +48,59 @@ bool Foam::dictionary::writeOptionalEntries
 
 // * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
 
-void Foam::dictionary::excessTokens
+void Foam::dictionary::checkITstream
 (
     const word& keyword,
     const ITstream& is
 ) const
 {
-    const label nExcess = is.nRemainingTokens();
-
-    if (!nExcess)
+    if (is.nRemainingTokens())
     {
-        return;
-    }
+        const label remaining = is.nRemainingTokens();
+
+        // Similar to SafeFatalIOError
+        if (JobInfo::constructed)
+        {
+            OSstream& err =
+                FatalIOError
+                (
+                    "",                 // functionName
+                    "",                 // sourceFileName
+                    0,                  // sourceFileLineNumber
+                    this->name(),       // ioFileName
+                    is.lineNumber()     // ioStartLineNumber
+                );
+
+            err << "'" << keyword << "' has "
+                << remaining << " excess tokens in stream" << nl << nl
+                << "    ";
+            is.writeList(err, 0);
+
+            err << exit(FatalIOError);
+        }
+        else
+        {
+            std::cerr
+                << nl
+                << "--> FOAM FATAL IO ERROR:" << nl;
+
+            std::cerr
+                << "'" << keyword << "' has "
+                << remaining << " excess tokens in stream" << nl << nl;
 
-    // Similar to SafeFatalIOError
+            std::cerr
+                << "file: " << this->name()
+                << " at line " << is.lineNumber() << '.' << nl
+                << std::endl;
 
-    if (JobInfo::constructed)
+            ::exit(1);
+        }
+    }
+    else if (!is.size())
     {
-        OSstream& err =
+        // Similar to SafeFatalIOError
+        if (JobInfo::constructed)
+        {
             FatalIOError
             (
                 "",                 // functionName
@@ -73,31 +108,24 @@ void Foam::dictionary::excessTokens
                 0,                  // sourceFileLineNumber
                 this->name(),       // ioFileName
                 is.lineNumber()     // ioStartLineNumber
-            );
-
-        err << "'" << keyword << "' has "
-            << nExcess << " excess tokens in stream" << nl << nl
-            << "    ";
-        is.writeList(err, 0);
-
-        err << exit(FatalIOError);
-    }
-    else
-    {
-        std::cerr
-            << nl
-            << "--> FOAM FATAL IO ERROR:" << nl;
-
-        std::cerr
-            << "'" << keyword << "' has "
-            << nExcess << " excess tokens in stream" << nl << nl;
+            )
+                << "'" << keyword << "' had no tokens in stream" << nl << nl
+                << exit(FatalIOError);
+        }
+        else
+        {
+            std::cerr
+                << nl
+                << "--> FOAM FATAL IO ERROR:" << nl
+                << "'" << keyword << "' had no tokens in stream" << nl << nl;
 
-        std::cerr
-            << "file: " << this->name()
-            << " at line " << is.lineNumber() << '.' << nl
-            << std::endl;
+            std::cerr
+                << "file: " << this->name()
+                << " at line " << is.lineNumber() << '.' << nl
+                << std::endl;
 
-        ::exit(1);
+            ::exit(1);
+        }
     }
 }
 

src/OpenFOAM/db/dictionary/dictionary.H

@@ -383,8 +383,10 @@ private:
         ) const;
 
 
-        //- Emit FatalIOError if excess tokens exist
-        void excessTokens(const word& keyword, const ITstream& is) const;
+        //- Check after reading if the input token stream has unconsumed
+        //- tokens remaining or if there were no tokens in the first place.
+        //  Emits FatalIOError
+        void checkITstream(const word& keyword, const ITstream& is) const;
 
 
 public:

src/OpenFOAM/db/dictionary/dictionaryTemplates.C

@@ -97,7 +97,7 @@ bool Foam::dictionary::readCompat
         ITstream& is = finder.ptr()->stream();
         is >> val;
 
-        excessTokens(keyword, is);
+        checkITstream(keyword, is);
 
         return true;
     }
@@ -144,7 +144,7 @@ T Foam::dictionary::lookupOrDefault
         ITstream& is = finder.ptr()->stream();
         is >> val;
 
-        excessTokens(keyword, is);
+        checkITstream(keyword, is);
 
         return val;
     }
@@ -178,7 +178,7 @@ T Foam::dictionary::lookupOrAddDefault
         ITstream& is = finder.ptr()->stream();
         is >> val;
 
-        excessTokens(keyword, is);
+        checkITstream(keyword, is);
 
         return val;
     }
@@ -212,7 +212,7 @@ bool Foam::dictionary::readEntry
         ITstream& is = finder.ptr()->stream();
         is >> val;
 
-        excessTokens(keyword, is);
+        checkITstream(keyword, is);
 
         return true;
     }
@@ -262,7 +262,7 @@ T Foam::dictionary::lookupOrDefaultCompat
         ITstream& is = finder.ptr()->stream();
         is >> val;
 
-        excessTokens(keyword, is);
+        checkITstream(keyword, is);
 
         return val;
     }

src/OpenFOAM/global/argList/argList.C

@@ -202,32 +202,46 @@ static void printBuildInfo(const bool full=true)
 
 // * * * * * * * * * * * * * Static Member Functions * * * * * * * * * * * * //
 
-void Foam::argList::warnTrailing(const ITstream& is, const label index)
+void Foam::argList::checkITstream(const ITstream& is, const label index)
 {
-    const label nExcess = is.nRemainingTokens();
+    const label remaining = is.nRemainingTokens();
 
-    if (nExcess)
+    if (remaining)
     {
         std::cerr
             << nl
             << "--> FOAM WARNING:" << nl
             << "argument " << index << " has "
-            << nExcess << " excess tokens" << nl << nl;
+            << remaining << " excess tokens" << nl << nl;
+    }
+    else if (!is.size())
+    {
+        std::cerr
+            << nl
+            << "--> FOAM WARNING:" << nl
+            << "argument " << index << " had no tokens" << nl << nl;
     }
 }
 
 
-void Foam::argList::warnTrailing(const ITstream& is, const word& optName)
+void Foam::argList::checkITstream(const ITstream& is, const word& optName)
 {
-    const label nExcess = is.nRemainingTokens();
+    const label remaining = is.nRemainingTokens();
 
-    if (nExcess)
+    if (remaining)
     {
         std::cerr
             << nl
             << "--> FOAM WARNING:" << nl
             << "option -" << optName << " has "
-            << nExcess << " excess tokens" << nl << nl;
+            << remaining << " excess tokens" << nl << nl;
+    }
+    else if (!is.size())
+    {
+        std::cerr
+            << nl
+            << "--> FOAM WARNING:" << nl
+            << "option -" << optName << " had no tokens" << nl << nl;
     }
 }
 
@@ -1141,7 +1155,7 @@ void Foam::argList::parse
                 source = "-hostRoots";
                 ITstream is = this->lookup("hostRoots");
                 List<Tuple2<wordRe, fileName>> hostRoots(is);
-                warnTrailing(is, "hostRoots");
+                checkITstream(is, "hostRoots");
 
                 for (const auto& hostRoot : hostRoots)
                 {

src/OpenFOAM/global/argList/argList.H

@@ -161,11 +161,15 @@ class argList
             const string& str
         );
 
-        //- Warn if there are input tokens remaining on the stream
-        static void warnTrailing(const ITstream& is, const label index);
-
-        //- Warn if there are input tokens remaining on the stream
-        static void warnTrailing(const ITstream& is, const word& optName);
+        //- Check after reading if the input token stream has unconsumed
+        //- tokens remaining or if there were no tokens in the first place.
+        //  Emits Warning
+        static void checkITstream(const ITstream& is, const label index);
+
+        //- Check after reading if the input token stream has unconsumed
+        //- tokens remaining or if there were no tokens in the first place.
+        //  Emits Warning
+        static void checkITstream(const ITstream& is, const word& optName);
 
         //- Read a List of values from ITstream,
         //- treating a single entry like a list of size 1.

src/OpenFOAM/global/argList/argListI.H

@@ -230,7 +230,7 @@ inline T Foam::argList::get(const label index) const
     T val;
     is >> val;
 
-    warnTrailing(is, index);
+    checkITstream(is, index);
 
     return val;
 }
@@ -244,7 +244,7 @@ inline T Foam::argList::opt(const word& optName) const
     T val;
     is >> val;
 
-    warnTrailing(is, optName);
+    checkITstream(is, optName);
 
     return val;
 }
@@ -309,7 +309,7 @@ inline Foam::List<T> Foam::argList::getList(const label index) const
     List<T> list;
     readList(is, list);
 
-    warnTrailing(is, index);
+    checkITstream(is, index);
 
     return list;
 }
@@ -323,7 +323,7 @@ inline Foam::List<T> Foam::argList::getList(const word& optName) const
     List<T> list;
     readList(is, list);
 
-    warnTrailing(is, optName);
+    checkITstream(is, optName);
 
     return list;
 }
@@ -341,7 +341,7 @@ inline bool Foam::argList::readListIfPresent
         ITstream is(optName, options_[optName]);
         readList(is, list);
 
-        warnTrailing(is, optName);
+        checkITstream(is, optName);
 
         return true;
     }