bug #75164: sr={brendan, sfraser}. Adding the generators |nsSubstituteC?String|, which will replace |ReplaceSubstring|. Also fixing a declaration in "nsAStringGenerator.h".

git-svn-id: svn://10.0.0.236/trunk@95820 18797224-902f-48f8-a5cc-f745e15eee43
2001-05-23 06:49:51 +00:00
parent d442d78367
commit 73c3c7385c
6 changed files with 492 additions and 2 deletions
--- a/mozilla/string/src/nsReadableUtils.cpp
+++ b/mozilla/string/src/nsReadableUtils.cpp
@@ -600,7 +600,179 @@ RFindInReadable( const nsACString& aPattern, nsReadingIterator<char>& aSearchSta
    return found_it;
  }

+PRBool
+nsSubstituteString::IsDependentOn( const nsAString& aString ) const
+  {
+    return mText.IsDependentOn(aString) || mPattern.IsDependentOn(aString) || mReplacement.IsDependentOn(aString);
+  }

+PRUint32
+nsSubstituteString::MaxLength() const
+  {
+    PRInt32 numberOfMatches = mNumberOfMatches;
+
+      // if we don't know exactly how long the result will be,
+      //  calculate the longest possible result
+    if ( numberOfMatches < 0 )
+      {
+        if ( mReplacement.Length() <= mPattern.Length() )
+          numberOfMatches = 0;  // substitutions shrink the result, so worst case is none
+        else
+          numberOfMatches = PRInt32(mText.Length() / mPattern.Length());
+                  // substitutions grow the result, so worst case is the maximum number of times |mPattern| can be found
+      }
+
+    PRInt32 costPerMatch = PRInt32(mReplacement.Length()) - PRInt32(mPattern.Length());
+    return mText.Length() + (numberOfMatches * costPerMatch);
+  }
+
+void
+nsSubstituteString::CountMatches() const
+  {
+    nsReadingIterator<PRUnichar> textEnd;
+    nsReadingIterator<PRUnichar> searchEnd = mText.EndReading(textEnd);
+
+    nsReadingIterator<PRUnichar> searchStart;
+    mText.BeginReading(searchStart);
+
+    PRInt32 numberOfMatches = 0;
+    while ( FindInReadable(mPattern, searchStart, searchEnd) )
+      {
+        ++numberOfMatches;
+        searchStart = searchEnd;
+        searchEnd = textEnd;
+      }
+
+    NS_CONST_CAST(nsSubstituteString*, this)->mNumberOfMatches = numberOfMatches;
+  }
+
+PRUint32
+nsSubstituteString::Length() const
+  {
+    if ( mNumberOfMatches < 0 )
+      CountMatches();
+    return MaxLength();
+  }
+
+PRUnichar*
+nsSubstituteString::operator()( PRUnichar* aDestBuffer ) const
+  {
+    nsReadingIterator<PRUnichar> replacementEnd;
+    mReplacement.EndReading(replacementEnd);
+
+    nsReadingIterator<PRUnichar> textEnd;
+    nsReadingIterator<PRUnichar> searchEnd = mText.EndReading(textEnd);
+
+    nsReadingIterator<PRUnichar> uncopiedStart;
+    nsReadingIterator<PRUnichar> searchStart = mText.BeginReading(uncopiedStart);
+
+    while ( FindInReadable(mPattern, searchStart, searchEnd) )
+      {
+        // |searchStart| and |searchEnd| now bracket the match
+ 
+          // copy everything up to this match
+        copy_string(uncopiedStart, searchStart, aDestBuffer);  // updates |aDestBuffer|
+
+          // copy the replacement
+        nsReadingIterator<PRUnichar> replacementStart;
+        copy_string(mReplacement.BeginReading(replacementStart), replacementEnd, aDestBuffer);
+
+          // start searching from where the current match ends
+        uncopiedStart = searchStart = searchEnd;
+        searchEnd = textEnd;
+      }
+
+      // copy everything after the final (if any) match
+    copy_string(uncopiedStart, textEnd, aDestBuffer);
+    return aDestBuffer;
+  }
+
+PRBool
+nsSubstituteCString::IsDependentOn( const nsACString& aString ) const
+  {
+    return mText.IsDependentOn(aString) || mPattern.IsDependentOn(aString) || mReplacement.IsDependentOn(aString);
+  }
+
+PRUint32
+nsSubstituteCString::MaxLength() const
+  {
+    PRInt32 numberOfMatches = mNumberOfMatches;
+
+      // if we don't know exactly how long the result will be,
+      //  calculate the longest possible result
+    if ( numberOfMatches < 0 )
+      {
+        if ( mReplacement.Length() <= mPattern.Length() )
+          numberOfMatches = 0;  // substitutions shrink the result, so worst case is none
+        else
+          numberOfMatches = PRInt32(mText.Length() / mPattern.Length());
+                  // substitutions grow the result, so worst case is the maximum number of times |mPattern| can be found
+      }
+
+    PRInt32 costPerMatch = PRInt32(mReplacement.Length()) - PRInt32(mPattern.Length());
+    return mText.Length() + (numberOfMatches * costPerMatch);
+  }
+
+void
+nsSubstituteCString::CountMatches() const
+  {
+    nsReadingIterator<char> textEnd;
+    nsReadingIterator<char> searchEnd = mText.EndReading(textEnd);
+
+    nsReadingIterator<char> searchStart;
+    mText.BeginReading(searchStart);
+
+    PRInt32 numberOfMatches = 0;
+    while ( FindInReadable(mPattern, searchStart, searchEnd) )
+      {
+        ++numberOfMatches;
+        searchStart = searchEnd;
+        searchEnd = textEnd;
+      }
+
+    NS_CONST_CAST(nsSubstituteCString*, this)->mNumberOfMatches = numberOfMatches;
+  }
+
+PRUint32
+nsSubstituteCString::Length() const
+  {
+    if ( mNumberOfMatches < 0 )
+      CountMatches();
+    return MaxLength();
+  }
+
+char*
+nsSubstituteCString::operator()( char* aDestBuffer ) const
+  {
+    nsReadingIterator<char> replacementEnd;
+    mReplacement.EndReading(replacementEnd);
+
+    nsReadingIterator<char> textEnd;
+    nsReadingIterator<char> searchEnd = mText.EndReading(textEnd);
+
+    nsReadingIterator<char> uncopiedStart;
+    nsReadingIterator<char> searchStart = mText.BeginReading(uncopiedStart);
+
+    while ( FindInReadable(mPattern, searchStart, searchEnd) )
+      {
+        // |searchStart| and |searchEnd| now bracket the match
+ 
+          // copy everything up to this match
+        copy_string(uncopiedStart, searchStart, aDestBuffer);  // updates |aDestBuffer|
+
+          // copy the replacement
+        nsReadingIterator<char> replacementStart;
+        copy_string(mReplacement.BeginReading(replacementStart), replacementEnd, aDestBuffer);
+
+          // start searching from where the current match ends
+        uncopiedStart = searchStart = searchEnd;
+        searchEnd = textEnd;
+      }
+
+      // copy everything after the final (if any) match
+    copy_string(uncopiedStart, textEnd, aDestBuffer);
+    return aDestBuffer;
+  }

 NS_COM 
 PRBool