commit 3542261261ae1213c6e038a0ad38f17a10b4e80d
Author: Tanmai Khanna <khanna.tanmai@gmail.com>
Date:   Wed Jul 22 19:18:28 2020 +0530

    Wordbound blank handling in post generation (#102)
    
    * Wordbound blanks merge when words merge.
    
    * Wordbound blanks apply to all output words when output of postgen rule are more than input words.
    
    * No regression for postgeneration without wordbound blanks.
    
    * Lots of tests added.

diff --git a/lttoolbox/fst_processor.cc b/lttoolbox/fst_processor.cc
index d462341..42decd4 100644
--- a/lttoolbox/fst_processor.cc
+++ b/lttoolbox/fst_processor.cc
@@ -274,6 +274,61 @@ FSTProcessor::readWblank(FILE *input)
   return result;
 }
 
+bool
+FSTProcessor::wblankPostGen(FILE *input, FILE *output)
+{
+  wstring result = L"";
+  result += L"[[";
+  wchar_t c = 0;
+
+  while(!feof(input))
+  {
+    c = static_cast<wchar_t>(fgetwc_unlocked(input));
+    result += c;
+
+    if(c == L'\\')
+    {
+      result += c;
+      result += static_cast<wchar_t>(fgetwc_unlocked(input));
+    }
+    else if(c == L']')
+    {
+      c = static_cast<wchar_t>(fgetwc_unlocked(input));
+      result += c;
+
+      if(c == L']')
+      {
+        int resultlen = result.size();
+        if(result[resultlen-5] == '[' && result[resultlen-4] == '[' && result[resultlen-3] == '/') //ending blank [[/]]
+        {
+          fputws(result.c_str(), output);
+          break;
+        }
+        else
+        {
+          c = static_cast<wchar_t>(fgetwc_unlocked(input));
+          if(c == L'~')
+          {
+            wblankqueue.push(result);
+            return true;
+          }
+          else
+          {
+            result += c;
+          }
+        }
+      }
+    }
+  }
+
+  if(c != L']')
+  {
+    streamError();
+  }
+  
+  return false;
+}
+
 int
 FSTProcessor::readAnalysis(FILE *input)
 {
@@ -425,7 +480,7 @@ FSTProcessor::readTMAnalysis(FILE *input)
 }
 
 int
-FSTProcessor::readPostgeneration(FILE *input)
+FSTProcessor::readPostgeneration(FILE *input, FILE *output)
 {
   if(!input_buffer.isEmpty())
   {
@@ -434,6 +489,7 @@ FSTProcessor::readPostgeneration(FILE *input)
 
   wchar_t val = static_cast<wchar_t>(fgetwc_unlocked(input));
   int altval = 0;
+  is_wblank = false;
   if(feof(input))
   {
     return 0;
@@ -451,17 +507,31 @@ FSTProcessor::readPostgeneration(FILE *input)
 
       if(val == L'[')
       {
-        blankqueue.push(readWblank(input));
+        if(collect_wblanks)
+        {
+          wblankqueue.push(readWblank(input));
+          is_wblank = true;
+          return static_cast<int>(L' ');
+        }
+        else if(wblankPostGen(input, output))
+        {
+          return static_cast<int>(L'~');
+        }
+        else
+        {
+          is_wblank = true;
+          return static_cast<int>(L' ');
+        }
       }
       else
       {
         ungetwc_unlocked(val, input);
         blankqueue.push(readFullBlock(input, L'[', L']'));
+        
+        input_buffer.add(static_cast<int>(L' '));
+        return static_cast<int>(L' ');
       }
 
-      input_buffer.add(static_cast<int>(L' '));
-      return static_cast<int>(L' ');
-
     case L'\\':
       val = static_cast<wchar_t>(fgetwc_unlocked(input));
       if(escaped_chars.find(val) == escaped_chars.end())
@@ -732,6 +802,59 @@ FSTProcessor::flushBlanks(FILE *output)
   }
 }
 
+void
+FSTProcessor::flushWblanks(FILE *output)
+{
+  while(wblankqueue.size() > 0)
+  {
+    fputws_unlocked(wblankqueue.front().c_str(), output);
+    wblankqueue.pop();
+  }
+}
+
+wstring
+FSTProcessor::combineWblanks()
+{
+  wstring final_wblank;
+  wstring last_wblank = L"";
+  
+  while(wblankqueue.size() > 0)
+  {
+    if(wblankqueue.front().compare(L"[[/]]") == 0)
+    {
+      if(final_wblank.empty())
+      {
+        final_wblank += L"[[";
+      }
+      else if(final_wblank.size() > 2)
+      {
+        final_wblank += L"; ";
+      }
+      
+      final_wblank += last_wblank.substr(2,last_wblank.size()-4); //add wblank without brackets [[..]]
+      last_wblank.clear();
+    }
+    else
+    {
+      last_wblank = wblankqueue.front();
+    }
+    wblankqueue.pop();
+  }
+
+  if(!last_wblank.empty())
+  {
+    wblankqueue.push(last_wblank);
+  }
+  
+  if(!final_wblank.empty())
+  {
+    final_wblank += L"]]";
+    need_end_wblank = true;
+  }
+  
+  return final_wblank;
+}
+
 void
 FSTProcessor::calcInitial()
 {
@@ -2093,36 +2216,65 @@ FSTProcessor::postgeneration(FILE *input, FILE *output)
   }
 
   bool skip_mode = true;
+  collect_wblanks = false;
+  need_end_wblank = false;
   State current_state = initial_state;
   wstring lf = L"";
   wstring sf = L"";
   int last = 0;
   set<wchar_t> empty_escaped_chars;
 
-  while(wchar_t val = readPostgeneration(input))
+  while(wchar_t val = readPostgeneration(input, output))
   {
     if(val == L'~')
     {
       skip_mode = false;
+      collect_wblanks = true;
     }
 
-    if(skip_mode)
+    if(is_wblank && skip_mode)
+    {
+      //do nothing
+    }
+    else if(skip_mode)
     {
       if(iswspace(val))
       {
+        if(need_end_wblank)
+        {
+          fputws_unlocked(L"[[/]]", output);
+          need_end_wblank = false;
+        }
+        
         printSpace(val, output);
       }
       else
       {
+        if(!need_end_wblank)
+        {
+          flushWblanks(output);
+        }
+        
         if(isEscaped(val))
         {
           fputwc_unlocked(L'\\', output);
         }
         fputwc_unlocked(val, output);
+        
+        if(need_end_wblank)
+        {
+          fputws_unlocked(L"[[/]]", output);
+          need_end_wblank = false;
+        }
       }
     }
     else
     {
+      if(is_wblank)
+      {
+        continue;
+      }
+      
       // test for final states
       if(current_state.isFinal(all_finals))
       {
@@ -2199,6 +2351,9 @@ FSTProcessor::postgeneration(FILE *input, FILE *output)
       }
       else
       {
+        wstring final_wblank = combineWblanks();
+        fputws_unlocked(final_wblank.c_str(), output);
+        
         if(lf == L"")
         {
           unsigned int mark = sf.size();
@@ -2239,11 +2394,12 @@ FSTProcessor::postgeneration(FILE *input, FILE *output)
             fputwc_unlocked(val, output);
           }
         }
-
+        
         current_state = initial_state;
         lf = L"";
         sf = L"";
         skip_mode = true;
+        collect_wblanks = false;
       }
     }
   }
@@ -2269,7 +2425,7 @@ FSTProcessor::intergeneration(FILE *input, FILE *output)
 
   while (true)
   {
-    wchar_t val = readPostgeneration(input);
+    wchar_t val = readPostgeneration(input, output);
 
     if (val == L'~')
     {
@@ -2414,7 +2570,7 @@ FSTProcessor::transliteration(FILE *input, FILE *output)
   wstring sf = L"";
   int last = 0;
 
-  while(wchar_t val = readPostgeneration(input))
+  while(wchar_t val = readPostgeneration(input, output))
   {
     if(iswpunct(val) || iswspace(val))
     {
diff --git a/lttoolbox/fst_processor.h b/lttoolbox/fst_processor.h
index 3276151..9d1e62e 100644
--- a/lttoolbox/fst_processor.h
+++ b/lttoolbox/fst_processor.h
@@ -103,6 +103,11 @@ private:
    */
   queue<wstring> blankqueue;
 
+  /**
+   * Queue of wordbound blanks, used in reading methods
+   */
+  queue<wstring> wblankqueue;
+  
   /**
    * Set of characters being considered alphabetics
    */
@@ -226,6 +231,21 @@ private:
    * Output no more than 'N' number of weighted analyses
    */
   int maxAnalyses;
+  
+  /**
+   * True if a wblank block ([[..]]xyz[[/]]) was just read
+   */
+  bool is_wblank;
+  
+  /**
+   * True if skip_mode is false and need to collect wblanks
+   */
+  bool collect_wblanks;
+  
+  /**
+   * True if a wblank has been processed for postgen and we need an ending wblank
+   */
+  bool need_end_wblank;
 
   /**
    * Output no more than 'N' best weight classes
@@ -257,6 +277,14 @@ private:
    * @param input the stream being read
    */
   wstring readWblank(FILE *input);
+  
+  /**
+   * Reads a wordbound blank (opening blank to closing blank) from the stream input -> [[...]]xyz[[/]]
+   * @param input the stream being read
+   * @param output the stream to write on
+   * @return true if the word enclosed by the wordbound blank has a ~ for postgeneration activation
+   */
+  bool wblankPostGen(FILE *input, FILE *output);
 
   /**
    * Returns true if the character code is identified as alphabetic
@@ -282,6 +310,7 @@ private:
   /**
    * Read text from stream (decomposition version)
    * @param input the stream to read
+   * @param output the stream to write on
    * @return the next symbol in the stream
    */
   int readDecomposition(FILE *input, FILE *output);
@@ -289,13 +318,15 @@ private:
   /**
    * Read text from stream (postgeneration version)
    * @param input the stream to read
+   * @param output the stream to write on
    * @return the next symbol in the stream
    */
-  int readPostgeneration(FILE *input);
+  int readPostgeneration(FILE *input, FILE *output);
 
   /**
    * Read text from stream (generation version)
    * @param input the stream to read
+   * @param output the stream being written to
    * @return the next symbol in the stream
    */
   int readGeneration(FILE *input, FILE *output);
@@ -303,6 +334,7 @@ private:
   /**
    * Read text from stream (biltrans version)
    * @param input the stream to read
+   * @param output the stream to write on
    * @return the queue of 0-symbols, and the next symbol in the stream
    */
   pair<wstring, int> readBilingual(FILE *input, FILE *output);
@@ -319,6 +351,18 @@ private:
    * @param output stream to write blanks
    */
   void flushBlanks(FILE *output);
+  
+  /**
+   * Flush all the wordbound blanks remaining in the current process
+   * @param output stream to write blanks
+   */
+  void flushWblanks(FILE *output);
+  
+  /**
+   * Combine wordbound blanks in the queue and return them
+   * @return final wblank string
+  */
+  wstring combineWblanks();
 
   /**
    * Calculate the initial state of parsing
diff --git a/tests/data/postgen.dix b/tests/data/postgen.dix
new file mode 100644
index 0000000..1bea34b
--- /dev/null
+++ b/tests/data/postgen.dix
@@ -0,0 +1,98 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<dictionary>
+  <alphabet/>
+  <sdefs>
+    <sdef n="test"/>
+  </sdefs>
+
+  <pardefs>
+    
+    <pardef n="el">
+
+      <e>
+        <p>
+          <l>el<b/></l>
+          <r>l<b/></r>
+        </p>
+      </e>
+      <e>
+        <p>
+          <l>el</l>
+          <r>l</r>
+        </p>
+      </e>
+    </pardef>
+
+   <pardef n="le">
+      <e>
+        <p>
+          <l>la<b/></l>
+          <r>se<b/>la<b/></r>
+        </p>
+      </e>
+      <e>
+        <p>
+          <l>las<b/></l>
+          <r>se<b/>las<b/></r>
+        </p>
+      </e>
+      <e>
+        <p>
+          <l>lo<b/></l>
+          <r>se<b/>lo<b/></r>
+        </p>
+      </e>
+      <e>
+        <p>
+          <l>los<b/></l>
+          <r>se<b/>los<b/></r>
+        </p>
+      </e>
+    </pardef>
+
+
+  </pardefs>
+
+  <section id="main" type="standard">
+
+     <e>
+        <p>
+          <l><a/>de<b/></l>
+          <r>de</r>
+        </p>
+        <par n="el"/>
+      </e>
+
+      <e>
+        <p>
+          <l><a/>o<b/>ho</l>
+          <r>u<b/>ho</r>
+        </p>
+      </e>
+
+      <e>
+        <p>
+          <l><a/>le<b/></l>
+          <r/>
+        </p>
+        <par n="le"/>
+      </e>
+
+      <e>
+        <p>
+          <l><a/>les<b/></l>
+          <r>le<b/>pe<b/>test<b/></r>
+        </p>
+      </e>
+
+      <e>
+        <p>
+          <l><a/>les<b/>pes<b/></l>
+          <r>les<b/>pes<b/>test<b/></r>
+        </p>
+      </e>
+
+  </section>
+
+</dictionary>
+
diff --git a/tests/lt_proc/__init__.py b/tests/lt_proc/__init__.py
index 5455c48..a4e0709 100644
--- a/tests/lt_proc/__init__.py
+++ b/tests/lt_proc/__init__.py
@@ -139,5 +139,59 @@ class WordboundBlankAnalysisTest(unittest.TestCase, ProcTest):
                         "[[t:b:456123; t:i:90hfbn]]^legge/legge<vblex><inf>$  [[t:s:xyz789]]^opp/opp<pr>$  ^opp/opp<pr>$ [[t:b:abc124]]^x/*x$ ^opp/opp<pr>$^./.<sent>$",
                        ]
 
+class PostgenerationBasicTest(unittest.TestCase, ProcTest):
+    procdix = "data/postgen.dix"
+    procflags = ["-p", "-z"]
+    inputs          = [ "xyz ejemplo ~o ho nombre.",
+                        "xyz ~le la pelota.",
+                        "El perro ~de el amigo.",
+                        "abc ~les testword"]
+    expectedOutputs = [ "xyz ejemplo u ho nombre.",
+                        "xyz se la pelota.", 
+                        "El perro del amigo.", 
+                        "abc le pe test testword"]
+
+class PostgenerationWordboundBlankTest(unittest.TestCase, ProcTest):
+    procdix = "data/postgen.dix"
+    procflags = ["-p", "-z"]
+    inputs          = [ "xyz ejemplo [[t:i:123456]]~o[[/]] [[t:b:abc123; t:i:123456]]ho[[/]] [[t:b:iopmnb]]nombre[[/]].",
+                        "xyz ejemplo [[t:b:poim230]]~o[[/]] ho [[t:i:mnbj203]]nombre[[/]].",
+                        "xyz ejemplo ~o [[t:b:abc123; t:i:123456]]ho[[/]] [[t:b:iopmnb]]nombre[[/]].",
+                        "xyz ejemplo ~o [[t:b:abc123; t:i:123456]]ho[[/]] ~le la [[t:b:iopmnb]]nombre[[/]].",
+                        "xyz ejemplo [[t:i:1235gb]]~o[[/]] [[t:b:abc123; t:i:123456]]ho[[/]] [[t:b:i4x56fb]]~le[[/]] la nombre.",
+                        "xyz [[t:i:123456]]~le[[/]] [[t:b:123gfv]]la[[/]] pelota.",
+                        "xyz ~le [[t:b:123gfv]]la[[/]] pelota.",
+                        "xyz ejemplo ~o [[t:b:abc123; t:i:123456]]ho[[/]] ~le [[t:b:io1245b]]la[[/]] [[t:b:iopmnb]]nombre[[/]].",
+                        "[[t:b:Z9eiLA]]El[[/]] [[t:s:8AjRFw]]perro[[/]] [[t:i:4_tPUA]]~de[[/]] [[t:b:Z9eiLA]]el[[/]] [[t:i:wSM6RQ]]amigo[[/]][]",
+                        "[[t:b:h5lVhA]]El[[/]] [[t:b:Z9eiLA; t:i:4_tPUA]]perro[[/]] [[t:b:Z9eiLA; t:i:4_tPUA]]~de[[/]] [[t:b:Z9eiLA]]el[[/]] [[t:i:npAFwg]]amigo[[/]][]",
+                        "[[t:b:Z9eiLA]]El[[/]] [[t:s:8AjRFw]]perro[[/]] [[t:i:4_tPUA]]~de[[/]] el [[t:i:wSM6RQ]]amigo[[/]][]",
+                        "[[t:b:Z9eiLA]]El[[/]] [[t:s:8AjRFw]]perro[[/]] ~de [[t:b:Z9eiLA]]el[[/]] [[t:i:wSM6RQ]]amigo[[/]][]",
+                        "[[t:b:Z9eiLA]]El[[/]] [[t:s:8AjRFw]]perro[[/]] ~de el [[t:i:wSM6RQ]]amigo[[/]][]",
+                        "[[t:b:Z9eiLA]]abc[[/]] [[t:i:123456]]~les[[/]] [[t:b:abc123; t:i:123456]]testword[[/]]",
+                        "[[t:b:Z9eiLA]]abc[[/]] ~les [[t:b:abc123; t:i:123456]]testword[[/]]",
+                        "[[t:b:Z9eiLA]]abc[[/]] [[t:i:123456]]~les[[/]] [[t:i:4_tPUA]]~de[[/]] [[t:b:Z9eiLA]]el[[/]] [[t:i:wSM6RQ]]testword[[/]]",
+                        "[[t:b:Z9eiLA]]abc[[/]] [[t:i:123456]]~les pes[[/]] [[t:i:4_tPUA]]~de[[/]] [[t:b:Z9eiLA]]el[[/]] [[t:i:wSM6RQ]]testword[[/]]",
+                        "[[t:b:Z9eiLA]]abc[[/]] [[t:i:123456]]~les[[/]] [[t:b:12bsa23]]pes[[/]] [[t:i:4_tPUA]]~de[[/]] [[t:b:Z9eiLA]]el[[/]] [[t:i:wSM6RQ]]testword[[/]]",
+                        "[[t:b:Z9eiLA]]abc[[/]] ~les [[t:b:12bsa23]]pes[[/]] [[t:i:4_tPUA]]~de[[/]] [[t:b:Z9eiLA]]el[[/]] [[t:i:wSM6RQ]]testword[[/]]"]
+
+    expectedOutputs = [ "xyz ejemplo [[t:i:123456; t:b:abc123; t:i:123456]]u ho[[/]] [[t:b:iopmnb]]nombre[[/]].",
+                        "xyz ejemplo [[t:b:poim230]]u ho[[/]] [[t:i:mnbj203]]nombre[[/]].",
+                        "xyz ejemplo [[t:b:abc123; t:i:123456]]u ho[[/]] [[t:b:iopmnb]]nombre[[/]].",
+                        "xyz ejemplo [[t:b:abc123; t:i:123456]]u ho[[/]] se la [[t:b:iopmnb]]nombre[[/]].",
+                        "xyz ejemplo [[t:i:1235gb; t:b:abc123; t:i:123456]]u ho[[/]] [[t:b:i4x56fb]]se la[[/]] nombre.",
+                        "xyz [[t:i:123456; t:b:123gfv]]se la[[/]] pelota.",
+                        "xyz [[t:b:123gfv]]se la[[/]] pelota.",
+                        "xyz ejemplo [[t:b:abc123; t:i:123456]]u ho[[/]] [[t:b:io1245b]]se la[[/]] [[t:b:iopmnb]]nombre[[/]].",
+                        "[[t:b:Z9eiLA]]El[[/]] [[t:s:8AjRFw]]perro[[/]] [[t:i:4_tPUA; t:b:Z9eiLA]]del[[/]] [[t:i:wSM6RQ]]amigo[[/]][]",
+                        "[[t:b:h5lVhA]]El[[/]] [[t:b:Z9eiLA; t:i:4_tPUA]]perro[[/]] [[t:b:Z9eiLA; t:i:4_tPUA; t:b:Z9eiLA]]del[[/]] [[t:i:npAFwg]]amigo[[/]][]",
+                        "[[t:b:Z9eiLA]]El[[/]] [[t:s:8AjRFw]]perro[[/]] [[t:i:4_tPUA]]del[[/]] [[t:i:wSM6RQ]]amigo[[/]][]",
+                        "[[t:b:Z9eiLA]]El[[/]] [[t:s:8AjRFw]]perro[[/]] [[t:b:Z9eiLA]]del[[/]] [[t:i:wSM6RQ]]amigo[[/]][]",
+                        "[[t:b:Z9eiLA]]El[[/]] [[t:s:8AjRFw]]perro[[/]] del [[t:i:wSM6RQ]]amigo[[/]][]",
+                        "[[t:b:Z9eiLA]]abc[[/]] [[t:i:123456]]le pe test[[/]] [[t:b:abc123; t:i:123456]]testword[[/]]",
+                        "[[t:b:Z9eiLA]]abc[[/]] le pe test [[t:b:abc123; t:i:123456]]testword[[/]]",
+                        "[[t:b:Z9eiLA]]abc[[/]] [[t:i:123456]]le pe test[[/]] [[t:i:4_tPUA; t:b:Z9eiLA]]del[[/]] [[t:i:wSM6RQ]]testword[[/]]",
+                        "[[t:b:Z9eiLA]]abc[[/]] [[t:i:123456]]les pes test[[/]] [[t:i:4_tPUA; t:b:Z9eiLA]]del[[/]] [[t:i:wSM6RQ]]testword[[/]]",
+                        "[[t:b:Z9eiLA]]abc[[/]] [[t:i:123456; t:b:12bsa23]]les pes test[[/]] [[t:i:4_tPUA; t:b:Z9eiLA]]del[[/]] [[t:i:wSM6RQ]]testword[[/]]",
+                        "[[t:b:Z9eiLA]]abc[[/]] [[t:b:12bsa23]]les pes test[[/]] [[t:i:4_tPUA; t:b:Z9eiLA]]del[[/]] [[t:i:wSM6RQ]]testword[[/]]"]
 # These fail on some systems:
 #from null_flush_invalid_stream_format import *